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1gvnbc | Just how much has my view been skewed by typical Westerns (films)? Was there really so much active violence between civilians and Indians? | In your typical Western movie every white family that moves anywhere is almost guaranteed to be attacked by "wild" hordes of Indians riding horses, whooping, and trying to kill all the white people. I have this inadvertent imagine of the West as a place where everyone was constantly killing everyone. Towns endlessly fighting off Indians. etc However, I have a sneaking suspicion most of the fighting vs Indians was really done by the Army, and there wasn't nearly so much of the romanticized "conquering of the wild frontier" by average people, instead just people trying to make a life for themselves.
*Main question:* **How likely is it that my view of the facts is completely skewed if I'm basing my knowledge on the Western film genre?**
----------
ps
Sorry if my question is poorly formed, but I hope you understand the gist of my question, which occurred to me while watching a Western during which I realized I couldn't actually make an argument for or against the reality portrayed. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1gvnbc/just_how_much_has_my_view_been_skewed_by_typical/ | {
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"I believe I can provide a summarized case study:\n\nOne example is the Paiute War (1860-1), in which the Paiute tribe of Pyramid Lake, Utah Territory (now Nevada) fought against the US. Though tensions were rising, and attacks both by and on Indians were rising, no open fighting occurred until a massacre of American workers at a way-station, who had supposedly kidnapped and raped an Indian girl. \n\nAfter this, a militia force was rounded up, and led to Pyramid Lake. It was ambushed and destroyed, by the greenness of its troops as well as the tactical ability of the Paiute leadership. Soon after, US troops took the same route, and though never winning an outright victory, the Paiute resistance petered out. In the end, a truce was signed. \n\nHere is an example of both organized and disorganized violence in the \"Wild West\", and the trouble differentiating them. The militia, raised from Carson City and Virginia City -- do we count them as army or as civilian? The Paiute attack on Williams Station -- is this an act of war, terrorism, or simply a few rogue Indians with revenge in their hearts? The US troops -- did they fight an Indian army or armed civilians? As often, the lines are blurred.\n\nAfter the first battle at Pyramid Lake, as far away as Sacramento civilians were clamouring about the \"Red Menace\" -- not commie, but Injun -- and how there would be ten thousand Indians at their doorstep any second. But... it never appeared. The threat existed entirely through xenophobic paranoia, and the loss of invincibility. \n\nImmortalised by the Pony Express and its hagiographers, an image stuck in many's mind is that of the rider being chased by hordes of Indians, arrows flying. My two cents: It is likely a fantasy, dreamed up by nostalgic fronteirsmen and entertainers (such as Buffalo Bill). \n\nAlthough this only provides limited scope into the threat of Native Americans to US civilians, I hope it's been informative!",
"Out on the plains of the Llano Estacado in West Texas, or just in most parts of the state being attacked by a party of Comanches was not unheard of. Unless you had some sort of agreement with what ever local band was nearby safety was not guaranteed. And as different Comanche bands did not recognize the treaties of other bands (something the settlers didn't understand) this would cause unrest, confusion and bloodshed. There are many notable raids to back this up, the most infamous being the raid on Parker's Fort in 1836. Now the Comanches fought with the whatever force confronted it, most notably the Texas Rangers and the US 4th Cavalry (*IIRC*), but there were occasions in which an entire town of settlers had to fight off a Comanche raid, the most famous being the Second Battle of Adobe Walls in 1874. Now these encounters and events I have given only pertain to the Comanche's of Texas, so this is not encompassing of all tribes in the \"wild west\", but due to the size and notoriety of the Comanche nation in American history along with Hollywood never caring about differentiating tribes this has probably led to the skewed portrayal of violence between civilians and indians in westerns. Hope this answered something.",
"There's a couple of ways to answer this question: through studying the actual events of history (as /u/ChiefBlanco and /u/zclcf30 have already done here), and studying the genre of Western films in context both with the time of their creation in the mid 20th century and with knowledge of the actual events of 19th century they purport to portray.\n\nI highly recommend the work of Richard Slotkin on this second approach. His trio of big books -- sometimes called the gunfighter trilogy -- explore the mythologizing of violence in American popular culture and the production of historical memory. In particular, he advances a number of theses about this violence, including ideas about \"regeneration through violence\" and attempts to locate an otherwise elusive national mythology in stories of such violence. *Regeneration Through Violence: The Mythology of the American Frontier, 1600-1860* is where the trilogy starts, then through *The Fatal Environment* (my favorite) and then the final, and best well known, *Gunfighter Nation*.\n\nI think that final book is what you want -- If your observation is that \"I have this inadvertent imagine of the West as a place where everyone was constantly killing everyone,\" then this book offers an explanation as to why that storyline of violence has gained prominence. This mythology has served different purposes for many audiences, making it a useful legend to resurrect and re-tell over and over again.\n\nNB: this is not to say that westward movement was *not* violent; this analysis simply examines why we retell these stories so much, at the expense of other viewpoints.\n\n_URL_0_\n"
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2p6m3l | how is it that the piratebay was able to be taken down by a single raid on a physical location? | I've never had a truly sound understanding of how the piratebay operated but I had thoughts that part of how they'd stuck around so long despite multiple take downs was that they never really operated entirely in any one location anywhere. This I thought provided them the means to simply pop up once again whenever they were taken down and also meant that if they were raided anywhere they has the means to start up again from elsewhere already in place.
I also read [this](_URL_0_) which seemed to provide a laymen's understanding of how they went about doing exactly what I just described. How then is it anyone was able to raid them and 'seemingly' be effective in taking them down this way. Why didn't anyone just do this before for that matter? I mean it happened back when it was under its original ownership and it did nothing to stop them.
EDIT: After reading the responses and the other similar thread linked to in the comments I think the short answer is nobody knows which unsurprisingly is probably why none of the relevant tech media have offered up any articles answering this question themselves. I figured this may have been the case, but I did wonder if there was any very savvy and informed guesses that could offer an interesting theoretical answer, howeve it seems no amount of nouse can penetrate this fog because the relevant details of how are likely being kept close to the chests of the authorities and the website owners for now.
I think personally, my theory for now is one I entertained to begin with which is that the owners simply hadn't implemented the type of raid proof architecture they spoke of previously at all, at least not close to the extent they may have described. In this theory, there is no special trick or tactics employed by authorities or vulnerability to the the way tpb theoretically set things up, just human frailty and a case of grandiose claims being found to be false. I don't find this particularly unlikely, they've previously talked about running servers from drones and moving to Sealand, or North Korea. Whatever the case, I'll miss them, they were a great symbol even if what they became since ownership from the founders was transferred, was perhaps something less than what they could have been.
The load balancer theory holds some weight on further re-reading of my source article, as it sounds like that was running through just the one virtual machine. But it seems that though the load balancer was a possible single point of failure for the operation it doesn't sound as though it should have made it impossible to simply start up a new one again (especially as they wouldn't have been out of pocket for the actual machinery) given the various other VMs for the operation should have still operated (or at least many of them) and it sounds like most of the other functions of the site which were catered to by specific VM's actually had redundancy (the article implies the load balancer didn't). This suggests then that if the measures they claimed to have taken had been taken, then the reason tpb isn't back up yet is because those who could put it back up, aren't for one reason or another. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2p6m3l/eli5_how_is_it_that_the_piratebay_was_able_to_be/ | {
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"It looks like the answer is in the same article you posted: \"All traffic goes through the load balancer\"\n\nFrom what I've been reading, this was precisely what was hit by the raid.",
"Not sure if this is entirely helpful, but here is a link to The Pirate Bay documentary \"Away From the Keyboard\" _URL_0_",
"decentralized networking will be the next big thing.\n\nsurely if they were serious about keeping TPB online they would have had had multiple points of entry. I'm thinking the operators have had enough and cant be assed bringing it back, they would have had a level of redundancy ",
"I use Kickass and IPT torrents, but I still hope Pirate Bay is not down for good. "
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3vp1va | Is there any evidence that a large scale, traumatic event (like the bombs dropped on Hiroshima and Nagasaki) can have a long lasting effect on the overall psyche of a culture? | I've heard theories that one of the reasons the Japanese are so "strange" as a culture is because the atomic bombs had some profound effect on their culture psychologically that's managed to persist even generations later. Is there any merit to this theory? | askscience | https://www.reddit.com/r/askscience/comments/3vp1va/is_there_any_evidence_that_a_large_scale/ | {
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"Japan was a closed country during a long time and started opening its borders less then two centuries ago. Since japanese culture developed without almost no external influence for so long it explains why it looks strange from outside.",
"[Effects of the devastation.](_URL_0_). I don't know that anything as specifically been done to identify cultural PTSD but that devastation certainly effected millions of individuals.\n\nThe traumatic event is not limited to the atomic bombs however but the devastation caused by all of WWII. The atomic bombs wrecked only 2 cities. Firebombing and conventional bombing [64 others](_URL_1_).\nDestruction of infrastructure, losses of men and equipment (value the country could have used elsewhere) overseas caused even more problems. "
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22u66j | When did getting/having a drivers license really become a thing required to have? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/22u66j/when_did_gettinghaving_a_drivers_license_really/ | {
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"In order to maybe cut down on some of the lackluster answers, I'll put in a few clarifying questions on what the original question (I presume!) is asking:\n\n1. When did a driver's license first become a valid form of identification in the US? Did it replace an older form of state issued ID? \n2. When did stores in American first have to ask for a form of identification to sell everyday age-controlled items like cigarettes and alcohol? (This is the most common reason to need a form of driver's license/state ID on you at all times) \n3. When did common government and non-government services start requiring an ID to access, such as setting up a bank account, voting, or getting a library card? "
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eqtdgy | When do the Jews become Monotheistic, and when do they see themselves as separate from other Semitic tribes and cultures? | At what point in Jewish history do the Jews become more strictly monotheistic? My current understanding (that I want to see alternatives too) is that Judaism was polytheistic, until after the Babylonian captivity when the Torah was composed--and after an encounter with a more monotheistic culture (Zoroastrianism, even though it is a dualistic system). Is it this encounter with the Persians that made the Jews monotheistic?
& #x200B;
Also, when do the Jews see themselves as different than other Semitic tribes and cultures? When do they see themselves as special, elect, and chosen by their God and thus different from the cultural context which they emerge from? For example, most Semitic cultures practiced human and child sacrifice, and so did the Jews, but isn't it the case that they gradually abandoned that process and saw themselves as different? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/eqtdgy/when_do_the_jews_become_monotheistic_and_when_do/ | {
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"/u/midwesternphotograph talks about [the evolution of Judaism from polytheistic to monotheistic](_URL_0_)\n\n/u/lcnielsen also [has a writeup about it](_URL_1_)"
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1fqqeg | Since capsaicin is water insoluble, how does it interact with water in spicy broths and salsas? | askscience | http://www.reddit.com/r/askscience/comments/1fqqeg/since_capsaicin_is_water_insoluble_how_does_it/ | {
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"Insoluble is a relative term. Capsaicin will dissolve to some extent in water, especially if it is hot (13 mg per liter at room temp). \n\nThe molecule does have a polar end with some oxygen, nitrogen and hydroxyl groups, so water does have something to hang on to when it interacts. It's possible it may form some kind of micelle if it's present in sufficient concentrations."
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1c76wx | Why is it that, despite having such a close relationship for all these years, there seems to be few diseases that can spread from human to dog and vice versa. Yet, pig flu and bird flu exist and can be passed to humans. | askscience | http://www.reddit.com/r/askscience/comments/1c76wx/why_is_it_that_despite_having_such_a_close/ | {
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"Influenza exists as in pigs and birds because they act as a reservoir. There's a large amount of those animals migrating everywhere and are always in close contact with one another. This makes it easy for the virus to jump to different birds and thrive. Occasionally, a strain of influenza will jump to humans as a zooinotic infection. Rarely does this virus have the ability to mutate again and jump to another human.\n\nDogs, or domesticated house dogs, do not live together in large packs or herds like birds and pigs do. Therefore, they do not have the opportunities for infections to mutate and jump to humans. It's a matter of probability of mutation that enables an infection to become zooinotic.\n\nWhen you begin to keep large amounts of animals together as livestock, that's when diseases can become zooinotic. For example, the outbreak of SARS virus began in civets in Asia that were mass produced and sold."
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b4iefp | Does sugar/sugary sweets directly cause rotting/decay of our teeth? | Or does it just feed the biofilms in our mouth that cause rotting? | askscience | https://www.reddit.com/r/askscience/comments/b4iefp/does_sugarsugary_sweets_directly_cause/ | {
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"No, not directly. Decay is caused by bacteria eating away at the enamel of the teeth. These bacteria will feed off of any kind of sugar or starch, not just sweets. Stuff like potato chips that cling to the teeth can often cause worse damage than sugars, which dissolve quickly in saliva before they can be consumed by said bacteria. "
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er5joz | I know Native Americans didn't have horses until Europeans showed up, but did they use any other animals for war, other than as pack animals? Battle llamas? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/er5joz/i_know_native_americans_didnt_have_horses_until/ | {
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"I cant speak for the possible usage of Llamas and Alpacas in combat, though maybe one of my South American counter parts could weigh in on the liklihood of releasing the Camelids of War. But in North America the only animal that may have been used would have been the domesticated dog. Dogs were commonly found across North America, and probably would have served to help defend a community in someway. Dogs make for great sentries, they can warn you of newcomers and are usually pretty good at seeing, hearing, and smelling those trying to approach your dwelling. The nature of conflict in pre-Columbian North America centered around raiding which itself focuses on swift actions to catch an enemy unaware. Ambushes occured both within and outside the confines of your community, and with this in mind it is plausible that dogs as travel companions as well as living in town could have helped to combat the ability for an enemy to sneak up on you. However this is a pretty universal human usage of domesticated dogs, and would not have been as much of a focus for warfare as other domesticated animals. \n\nOne quick side note would be that dogs were sometimes used for transport beyond the stereotypical sled dogs of the north. But again I do not think this was used primarily for warfare and any benefit from it would have been a result of transport becoming easier in general as opposed to dogs being used primarily to transport items for war. \n\n\nTLDR: the only animal that was domesticated and that would have played any role during conflict was the dog, however dogs and humans have such a deeply linked relationship that any benefit in warfare would have most likely been only an added benefit and far from the sole reason these communities had domesticated dogs."
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1cp991 | Towards the centre of the galaxy, do the planets have "daylight" 24/7 due to the high concentration of stars in close proximity? | askscience | http://www.reddit.com/r/askscience/comments/1cp991/towards_the_centre_of_the_galaxy_do_the_planets/ | {
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"Despite the size of the sun, even within our star system, the size and luminosity of the sun is great reduced at a distance. For example, this depiction of how our sun probably looks from Pluto: _URL_0_\n\nThe main difference would just be a very star-filled night sky rather than complete daylight.",
"You can come up with the ballpark estimate on your own with some simple math. We know that light follows the [inverse-square law](_URL_0_). I.e. a light source that is twice as far away will give you 1/4th the energy, all else equal.\n\nLet's ask the question: if all the stars were 4.2 light years away from the planet in question, how many stars would there have to be to equal the amount of energy the earth receives from the sun? 4.2 light years is chosen because that's the distance from Earth to Alpha Centauri, the closest star (besides the sun). This is a very generous distance (generous, meaning most stars would be much further than this). We assume all stars put out the same amount of light as the sun. This is also a generous assumption, as the [sun is brighter than 85% of stars in the Milky Way](_URL_1_).\n\nUsing the following mathematica code (because it provides the small convenience of conversion from light minutes to light years...). You can just as easily do this by hand.\n\n sunDistance = Quantity[8.355, \"LightMinutes\"];\n alphaCentauriDistance = Quantity[4.2, \"LightYears\"];\n (alphaCentauriDistance/sunDistance)^2\n\nThe answer: 6.99\\*10^10 stars of brightness equal to the sun, at a distance of earth - Alpha Centauri.\n\nThere are about 300 billion stars in the Milky Way. That's 30\\*10^10 stars, to line up the decimal points. So we'd need a significant fraction of the Milky Way's stars (7/30) concentrated in a fairly small sphere (radius 4.2 light years) to achieve brightness equivalent to what the Earth receives from the sun. The diameter of the milky way is 100,000 light years, for comparison.\n\nFrom this ballpark estimation, we can conclude that no planet comes close to achieving the brightness that Earth receives from the Sun, ignoring the star(s) in the planet's solar system, especially considering the two generous assumptions we made earlier.\n\nSummary: no, because of the inverse-square law.",
"Fyi your question reminds me of the classic Asimov short story ...\n\n _URL_0_\n\nOut of curiosity is this what prompted your question?",
"Thank you for the explanation velcommen. j_mcc69 asks an interesting question to which I very much would like to know the answer to.\n\nWhenever we see a picture of a galaxy, the centre always seems to be so bright! I have always wondered what it would be like to live on a planet there.\n\nIt is a shame that there is no data regarding the concentration of stars, and their average distance to one another there.\n\n\"Daylight\" is also a subjective measurement, as the iris would expand to allow in more light to make the brain interpret the dimness as maybe something compared to a cloudy day.\n\nI suppose my question, then, should be \"In the middle of the night, at the centre of the galaxy, i. how bright is it compared to the middle of the day? ii. Roughly taking into account the ability of the iris to adjust incoming light being let into the eye, how would it compare to a cloudy day on earth i.e. would we be able to walk around unhindered or would it be better/worse than a clear night with a full moon showing?\" \n\nMore importantly, if the light from the stars is significant, what would this say about the impact on the diameter of a habitable zone for a planet around a star where life could come into being. Presumably, there will be more light on outer planets allowing processes such as photosynthesis to a better degree, but heating would still be a problem."
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6r7ljj | why are parents more worried about giving their kids more freedom compared to the 70's to 90's when the crime rate was higher? | _URL_0_ | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6r7ljj/eli5why_are_parents_more_worried_about_giving/ | {
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"Define freedom? Kids have far more freedom in some ways than previous generations. Cellphones, social media, etc.",
"The actual crime rate was higher, but the perception of crime is higher now. Lots of people talk about how the world got unsafer. That is not based on actual crime statistics (which have all been going down) but rather on the fact that because we live in such an interconnected world nowadays, we hear *everything*. And we hear it 24/7 due to the constant news cycle. That means people are hearing about things that happen that they would not have heard about 20 or 30 years ago, which makes it seem like these things are happening more often to them. "
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1f58zk | colony collapse disorder | I ran a search in ELI5 and didnt see anything thus far. How widespread and complex is this issue? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1f58zk/eli5_colony_collapse_disorder/ | {
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"It's pretty widespread, but it's not all that complex. Current research indicates that it's linked to the use of a class of insecticides called neonicotinoids. Europe has, as a result, already banned use of these pesticides, and if/when their bee population begins to recover, we'll have a definite answer."
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1odd17 | the concept of light years and how it is that we can measure distance with time | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1odd17/eli5_the_concept_of_light_years_and_how_it_is/ | {
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"The speed of light in a vacuum is a constant. The distance it travels in a year is thus also a constant. And that distance is large enough that it's a convenient measure of large distances. Though for what it's worth, there are other units that astronomers also prefer in certain contexts, such as the parsec. ",
"A light year is simply the distance light travels in one year. It's a measure of length, much like meters, feet, or inches. It's just a LOT.",
"\"Light-year\" means \"light-speed\" x \"year\", so the units (X meters/year * year = X meters) work out to a distance, not a time, even though the unit has the suffix \"-years\".",
"Measurements like meters and yards are arbitrary; their lengths were determined by nothing more than man's preference. A light-year, however, is a measure of distance with reference to a constant, objective frame--how far light can travel over the course of one year. Since light travels at about 300,000,000m/s, a light-year can be easily calculated.\n\n300,000,000m/s * 60s/min = 18,000,000,000m/min\n\n18,000,000,000m/min * 60min/hr = 1,080,000,000,000m/hr\n\n1,080,000,000,000m/hr * 24hr/day = 25,920,000,000,000m/day\n\n25,920,000,000,000m/day * 365day/yr = 9,460,800,000,000,000m/yr\n\nOr, in scientific notation:\n~9.46*10^15 m (it's redundant to put /yr)\n\n\nThat is a light-year. It's just a calculation of how far light can travel in one year. And it's always constant, too, because light travels at the fastest possible speed in the universe.",
"Follow up to OP's question,\n\nHow does one measure/estimate the distance of objects = > a light year from us?"
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41isjg | why is the sound quality so poor over airplane tannoys? | In a closed environment, surely there's no reason why the sound quality can't be perfect... in all my years on flying, I'd say more than 50% of the time I literally don't have a clue what the captain or cabin crew are saying due to lack of clarity and or / low volume. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/41isjg/eli5_why_is_the_sound_quality_so_poor_over/ | {
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"For those wondering, 'tannoy' is a British term for a loud speaker or public-address system. [From Wikipedia](_URL_0_), it comes from a company's name, Tannoy:\n\n > \"It became a household name as a result of supplying PA systems to the armed forces during World War II, and to Butlins and Pontins holiday camps after the war.\"",
"Two problems: The confines of a fuselage are a nearly impossible place to evenly distribute intelligible speech audio. The ceiling is so low that you can't evenly space speakers without either leaving holes in coverage or causing overlaps that ruin intelligibility.\n\nAlso, the microphones being used are designed designed for person-to-person communication (radio microphones and telephone headsets) and the signal the generate seldom works well for speaking to large groups."
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2ouv63 | why and how do lights flicker when faulty, and how does hollywood recreate faulty lights for shows | I was walking downstairs today and my apartment stairwell light was flickering (fluorescent), and I couldnt figure out why it was doing so, i.e how being faulty causes it to flicker, not completely not work. Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ouv63/eli5_why_and_how_do_lights_flicker_when_faulty/ | {
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"This is caused by a [preheater](_URL_0_) which doesn't function properly. When the lamp is ready to start up it sends a jolt, which starts the preheater. This jolt also lights up the gass in the light, after this the preheater kicks in and the light turns on properly. When the preheater is broken, you only see the flickr. And since it continues to try to turn itself on, it continues to flickr. \n\nSo if you want to recreate this effect, save your preheaters and put them in lamps which you want to flickr.\n\nTLDR: The preheater is broken, so the light can't turn on properly."
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xrnw4 | Atoms, molecules and ions. | In high school, we studied that matter can exist in two forms:
1. Substance - Matter of which all physical bodies are composed.
2. Physical Fields which can be gravitational, electromagnetic, nuclear etc.
The substance can be made from:
-Atoms
-Molecules
-Ions
Again, we studied this in high school so I am not completely sure whether I included everything. Feel free to correct me.
So, one thing which I couldn't understand was how can some substances be made from only one type of particles.
For example, distilled (pure) water H2O is made from molecules. Does that mean that it doesn't have even one atom in it, nor one ion?
Or sodium chloride NaCl, which is an ion based compound. Does it mean that it doesn't have a single molecule or atom in it?
I am not very familiar with particle physics or chemistry so please go easy on me for my poor knowledge and understanding. | askscience | http://www.reddit.com/r/askscience/comments/xrnw4/atoms_molecules_and_ions/ | {
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"What you have learned is a simplification of what's really going on.\n\nIn reality, everything is composed of 'fundamental particles' (also called elementary particles). These include things like protons and electrons. They are fundamental because they aren't made of anything else, you can't cut them into pieces, they are the smallest possible excitation of reality. They can have electric charge, mass and so on.\n\nOther stuff is made of fundamental particles. For instance, atoms are made of a nucleus of protons and neutrons with a large field of electrons around them. The protons and neutrons are themselves made of quarks (which are fundamental). In the nucleus, everything is held together with the 'strong force' which is one of the physical fields. On larger scales, stuff is held together by the electromagnetic force.\n\nMolecules are made of atoms. For instance, two oxygen atoms can bond to form an oxygen molecule. This involves partially sharing electrons between the atoms. The molecule forms and is stable because it's a lower energy state for the atoms to share electrons than for them to stay apart.\n\nIons are what you get if you take electrons away from an atom (or molecule), or add extra ones. Normally the atom has N positively charged protons in the nucleus, which cancel with N negatively charged electrons in its electron cloud. If you change the number of electrons, things aren't balanced any more and there's an overall charge on the ion that can cause new effects.\n\nNow, you may have noticed I've referred to particles as fields a few times. This is for multiple reasons. First, quantum objects do not have well defined positions and things, and are really described by a set of possibilities for what they could be doing - they only collapse to one particular possibility if you measure them! That means you have to describe what things are doing using probability fields.\n\nAs well as this, fields in the sense you talk about are themselves more fundamentally described in terms of exchanging particles! For instance, the electromagnetic field turns out to be described by the interacting particles exchanging photons (which are light, and are a fundamental particle).\n\n'Substance' isn't really an idea of scientific merit beyond high school level. For instance, when you touch something you aren't interacting with 'substance' as you seem to think of it, but rather are feeling the repulsion of electrons in that substance against the electrons in your hands. That's an electromagnetic interaction, a field!\n\nNow, that's a lot of information in a very short space. Feel free to ask if it's unclear or you have more questions."
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1p2cki | How scientifically valid is the Myers Briggs personality test? | I'm tempted to assume the Myers Briggs personality test is complete hogwash because though the results of the test are more specific, it doesn't seem to be immune to the Barnum Effect. I know it's based off some respected Jungian theories but it seems like the holy grail of corporate team building and smells like a punch bowl.
Are my suspicions correct or is there some scientific basis for this test? | askscience | http://www.reddit.com/r/askscience/comments/1p2cki/how_scientifically_valid_is_the_myers_briggs/ | {
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"It's not nearly as valid now as it once was. Much of the current personality research stems from the Five-Factor model (FFM), which is affiliated with the Big Five. The Big Five are openness, conscientiousness, extraversion, agreeableness, and neuroticism. If you want to learn more about the Five-Factor model or personality traits, I'd recommend checking out anything by David Funder or Lewis Goldberg. Here are two integral articles to the study of personality:\n\nFunder's 1991 [article](_URL_1_)\n\n[Goldberg's piece on phenotypic personality traits] (_URL_0_)",
"MBTI is not generally regarded as being particularly valid and you will be hard pressed to find any 'serious' research being carried out using it - although you may find some research into its effectiveness as, despite its many flaws and its pigeon holing of people into 16 neat categories, it has become a hugely popular tool with recruiters and HR departments.\n\n\n\nA decent paper (Boyle, 1995) analysing the effectiveness of MBTI can be found [here](_URL_0_). \n\n\nThe final line of its introduction sums things up nicely \"*In view of these serious \nlimitations, routine use of the MBTI is not recommended, and psychologists should be cautious as to its likely \nmisuse in various organisational and occupational settings.*\"",
"I am the lead psychometrician at a personality test publisher, so I will attempt to answer your question.\n\nTo begin, it is important to note that no test is \"scientifically valid\". Validity is not an element of a test, but specifically has to do with test score interpretation. (see the Standards for Educational and Psychological testing 1999, or Messick, 1989). That being said, the Myers Briggs is not a scientifically valid personality assessment. However, personality assessments can be validated for specific purposes.\n\nMoving onto the bigger issue with the Myers-Briggs: Decision consistency. The Myers-Briggs proclaims a reliability (calculated using coefficient alpha) of between .75-.85 on all of its scales (see Myers-Briggs testing manual). These are general, industry standard reliability coefficients(indicating that if you were to retest, you would get a similar score, but not exact). However, the Myers-Briggs makes additional claims about bucketing individuals into 1 of 16 possible personality types. That you can shift up or down a few points if you were to retake the test on any of the four distinct scales means that you may be higher on one scale than another simply through retaking the test due to measurement error. In fact, literature shows that your personality type will change for 50% of individuals simply through retesting. (Cautionary Comments Regarding the Myers-Brigg Type inventory, Consulting Psychology Journal: Practice and research, summer, 2005). This result indicates very low decision consistency. The low decision consistency is also a mathematical inevitability given 16 personality profiles using 4 scales and scale reliability around .8.\n\nGiven the low decision consistency, and given that claims the Myers-Briggs makes about about your personality(validity information) depends on the decisions made by the test to be consistent and not subject to change simply based on retesting, it is highly unlikely that there can be a solid validity argument supporting the Myers-Briggs as a personality indicator. Maybe there are studies showing that it can be used in a very specific context, but sweeping generalizations about the tests use are not going carry much weight.\n\nNow, as a working professional in the field, the Myers-Briggs does NOT have a good reputation as being a decent assessment. It has marketed well to school systems and has good name recognizability, but it is not a well developed exam. There are much better personality assessments available, such as SHL's OPQ32 or The Hogan personality inventory. Now, I don't want to say any of these are good. The best correlations between job performance and personality assessments is about .3 (indicating about 9% of the variance in a persons job performance can be accounted for by a personality assessment). That is the BEST personality assessments can do in terms of job performance... and a correlation of .3 is not worth very much (considering that tests like ACT or the SAT can correlate upwards of .7 with first year college GPA under ideal circumstances).\n\n",
"Question: You know how people categorize dog breeds by personality traits? \"Cockerspaniels are mistrustful of strangers but loyal\"; \"Retrievers are playful and friendly\", etc. Would you call that 'scientifically valid'? Probably not, but you probably believe that they are mostly accurate generalizations, and you'd consider them before adopting a puppy for your child. This is more or less how I regard MBTI - probably valid but impossible to declare it's truly scientific. Like much in the field of psychology, MBTI relies heavily on self-reporting and generalizations/statistical analysis and therefore is very hard to say. \n\nMore in depth:\n\nMBTI is about identifying trends surrounding people who share similar personality traits. It's basically the application of statistical analysis of typically fickle human subjects, which means it relies on generalizations.\n\nAnything to do with psychology is tricky when it comes to scientific verification, especially when it relies on self-reporting. When two people say they love something, are they experiencing the same biochemical activity and sensation? Do they love that thing for exactly the same reasons? Would they behave the same way toward that thing? Impossible to know.\n\nLet's look at the what makes up the MBTI (Myers-Briggs Type Indicator):\n\n1) It asserts that human personalities have traits that can be determined through examination and testing. Specifically, MBTI focuses on four pairs of them. Each pair of traits are opposites - introversion/extroversion, sensor/intuitive, thinking/feeling, judging/perceiving. MBTI posits that people have an preference for one of the traits in a pair (just a preference - not an absolute).\n\n2) MBTI theorizes that people of like preferences share other personality traits. By analyzing groups of people who all have the same types, they assembled 'personality profiles' which summarize common traits among each personality type.\n\n3) MBTI also seeks to analyze how different types interact with one another - in what ways do ENFP's interact with INTJ's, for example? Are there common communication breakdowns due to personality differences? Are there complimentary personality types, e.g., an impulsive creative person that is best paired with a meticulous organized one?\n\nThese three tenets rely on generalizations and statistical analysis.\n\nLet's look at one of the four types that MBTI focuses on:\n\n Introversion/extroversion. MBTI tends to describe this as 'where one gets one's energy from'. An introvert is refreshed with time alone or with a few friends but finds constant social interaction draining. An extrovert is invigorated by socially interacting with many people. \n\n Now, the definition they use sounds scientifically hazy - 'where you get your energy from'. What they mean by that is that when someone acts against their type - such as when an introvert has to force extroversion at a party - they get fatigued doing so. \n\n That doesn't sound like a very science-y definition, does it? However, I can self-report that it's true for me (and I have a feeling that any introvert would agree). I get drained from having to prolong social activity amount groups of people or strangers (and sometimes even friends). I have no idea how you'd prove that it was 'scientifically valid' though. All we can do is poll a lot of people, and decide on a consensus of what's 'true' based on the self-reporting. Which is what MBTI does.\n\nTo me, everything about MBTI is like that - stuff that's probably true, but can't be tested. \n\nI'm going to break the rules here and relate an anecdote (sorry - I promise I'm not using it to replace data - I'm doing it to make a related point). I really got into MBTI as a teenager, and became very familiar with the personality types, how the theory worked, etc. I correctly predicted the types of all my friends and family before having them take the DDLI (one of the more thorough tests). I was never wrong. This says to me that there's something valid about the typing and categorization process, at least. What I can't say is that it had predictive power - it more or less was just a way to summarize and categorize things about myself and people that I already knew. Typically, one of the traits of a scientific theory is that it must have predictive power. MBTI can *suggest* how an interaction between personality types *might* go down based on observations of generalized behavior.\n\nTo add to the issue of being impossible to declare a science - how would you scientifically test it? You could test groups of couples for their types and see if couples that have been together for 5+ years have 'compatible' types according to MBTI, but how do you eliminate all the non-personality reasons why couples stay together or split, like physical attraction, economic reasons, shared interests, etc?",
"While I generally agree with the leading answers in here, I'd like to add 2 things:\n\n1) It's not a test; it's called an 'indicator' because it's designed to give a relative idea of a person, not a specific answer.\n\n2) Having been on many hiring committees, I find it useful, but I don't support its pre-employment use. I like to give people the option to take it (on company time) during their orientation. It can help assess what kind of work environment is best for the employee, and which people they might work best with.",
"What about [Jung's Cognitive Functions?](_URL_0_)\n\nI read once that they could be both identified and demonstrated using EEG scans. Does this mean some form of scientific validity exists regarding these functions?\n\nedit: Thank you kindly for gold :)",
"There are a ton of book chapters, meta-analyses, and qualitative reviews that go into the realm of 'personality assessment.' Yet there is no real agreement within the scientific community, at least from my perspective, on which personality measure is most valid. What I'm about to say is explained through the lens of an Industrial/Organizational Psychologist, so keep that in mind. \n\nFrom what I recall, early research on personality was more concerned with identifying outliers (i.e., the crazies). That is, they were designed to find out if you had any sort of psychosis. Later on, some of these tests were adapted to focus on the normal person. Academia was overwhelmed with a number of different personality theories and measures. In other words, even though researchers were measuring personality, they weren't all measuring personality in the same way. This could (and did) cause problems. For instance two researchers could use different measures of extraversion. One of these measures is reliable, the other measure isn't. They were both studying the relationship between extraversion and job performance. In the first study they found a pretty decent effect size (.60), however, because the reliability was such crap on the second measure in the second study the relationship between extraversion and job performance was really crappy (.02). \n\nWhen authors when to meta-analytically combine these results (even after applying corrections), researchers found that personality doesn't really predict performance (_URL_1_). However, around 10 years later, another meta-analysis looking at the link between personality and job performance came out and they found some pretty awesome results (_URL_2_). Why? Cuz they limited themselves to 'reliable' measures. Mostly the FFM of personality. \n\nWhenever I collect measures of personality I tend to stick to FFM stuff by PAR (really McCrae and Costa). They have a bunch of stuff that is pretty reliable and has gone through several psychometric evaluations. \n\nTeam Building on the other hand is an entirely different beast... Research has shown that you can't simply look at the means of the team to predict performance - What is more valuable are other statistics (Variance, Min, Max, etc.) For instance this article... _URL_0_\n\nSorry for the complete lack of 'scientific speak,' but personality isn't my main topic area and I'm busy feeding my kid. Probably should have thought this through before my first post on reddit ever\n",
"My experience of the field of psychology is that it is very large and diverse, and how personality and character function is understood is fairly contentious and the validity of any tests are dependent on the purpose of the test.\nThe most robust empirically sound test I am aware of is the [Strange Situation](_URL_1_), which measures one's \"attachment\" to others. Knowing one's attachment style can be profound, assuming you understand and are open to what it actually means, which without training or a helpful therapist can be difficult.\nLess robust, but much more similar to Myers Briggs in description are the psychoanalytic character styles, best described by Nancy McWilliams in [Psychoanalytic Diagnosis](_URL_0_). This isn't psychometric testing and cannot be easily empirically validated - however it does find some validation in how it helps practitioners understand their clients and patients (and selves), so to better be able to help them with their concerns.\nAnd there are other tests still, to help decide if a person is more suitable for prison, or community treatment, or suited for a certain high stress activity, etc., etc., the validity for each test being dependent on its desired outcome.\nSo I guess what I am saying is how valid Myers Briggs is depends partly on what you're using it for and how consistent the results are, which at least according to [u/Mockingbird42's](_URL_2_) informative post, is not very.",
"I'm going to take a slightly different tack, and give you some info on how the Myers-Brigg was created. The test was created prior to the second world war by two women; Katherine Briggs, and her daughter Isabel Briggs Myers. They had no formal educational background in psychology when they created the test (Katherine started the work, and Isabel took it, and built upon it). Katherine had an interest in psychology which she built upon after reading a translation of one of Carl Jung's works, which hypothesised that a person's consciousness had two perceiving functions (sensation and intuition), and two judging functions (thinking and feeling). These are modified by two attitude types, extraversion and introversion. Katherine had developed her own theory on how consciousness and personality worked, and had come up with a similar hypothesis. Katherine and Isabel used Jung's work extensively, and came up with their own, four-dimensional, typology for human consciousness (they added a fourth dimension to the three identified in Jung's work). None of this was done using scientific principles, or indeed in association with any psychological schools. This was an unscientific interpretation of Jung's work, which in itself is flawed, not least because Jung and Freud's work should more properly be thought of as psychoanalysis, which is not a science, rather than psychology, which is. In order to give a veneer of respectability and quantitative objectivity to the Myers-Brigg Personality Type Indicator, Isabel learned statistical analysis from a personnel manager at a bank, in order to compile a test in a questionnaire form.\n\nSo, this was a test created at a time when psychology was a very poorly defined and nascent field, that at the time was largely overshadowed by the school of psychoanalysis. Jung's work, which was the most extensively used work in compiling the test, was not based on testable hypotheses and is hugely controversial; it is not commonly used today (although there are a die-hard group of Jungian psychologists who believe his work to be almost gospel). The Test itself became popular because it of the complementary rise of the HR school of thought within management at the time. Essentially, the early days of management studies were concerned simply with efficiency and transactive leadership (i.e., I punish or reward the worker to make them do what I want). However, a key thing that changed this was something known as the Hawthorne Studies; essentially, these were a series of studies to determine how to make workers more efficient. What they found, was the simple act of being studied made workers more efficient - basically, they conducted experiments where they altered the light levels on a factory floor, and they found that whether they raised the lighting levels or lowered them, the workers were more efficient, because they felt valued by being studied. The HR school believed that by taking an interest in workers, and trying to understand them, you could get better efficiency. Suddenly, along comes a test that offers an objective, \"scientific\", quantitative way to study your workers' personalities - and the rest, as they say, is history.\n\nAs others have pointed out, the science behind the Myers-Brigg is bunk, and to answer the OP's question, no, it is not a scientific personality test. By addressing the historicity of its creation, we can see how this came to be.\n\ntl;dr: The test was created between the two world wars by two women with no formal training in psychology or psychometric testing, relying heavily on a controversial psychoanalyst's work. The popularity of the test can be explained in part by the convergent growth of the HR school within management studies, which believed that by studying and understanding workers, you would have a more productive work force. The test is bunk, and you should not take it seriously.",
"Calling the Meyers Briggs or most any such test a personality test is somewhat misleading. Behavioral inventory is a more accurate phrase. Any such \"test\" based on self reporting can only hope to illustrate the subject's behavioral tendencies. Probably not really valid in a strict scientific sense, but nonetheless useful in helping an individual understand themself and their responses to given situations. ",
"There are two very distinct issues at play here. One is the validity of the MBTI theory itself, i.e. the 16 types and underlying Jungian cognitive-functional theory.\n\nAnother issue entirely is the validity/accuracy of *tests* which claim to be able to determine someone's type based on their answers to a list of questions.\n\nKeeping these issues separate is very useful when discussing or thinking about MBTI.",
"This is the most scientific research I have found on the topic. Dario Nardio uses brain imagining to prove that people of the same \"type\" use their brains significantly more similarly than other types. In terms of testing, this is potentially an accurate test rather than relying in self report through the conventional instrument. \n\n_URL_0_\n\nFrom a YouTube video of Dr. Nardi presenting his research at google: \n\nUCLA professor and author, Dario Nardi, has discovered that people of different personality types don't merely rely on different brain regions -- they use their brains in fundamentally different ways. Using colorful anecdotes and brain imagery, Dr. Nardi shares key insights from his lab. Among these insights: how people of different personalities can find and sustain a state of creative flow. This talk is suitable for a general audience including those who have passing familiarity with the Myers-Briggs types.\n\n_URL_1_\n",
"So I'm late to the game here, but just in case anyone scrolls to the bottom.\n\nA few things:\n\n1) It's an \"inventory,\" not a \"test.\" Any certified MBTI practitioner would know this. Which leads me to believe the vast majority of folks here are not. Which leads me to...\n\n2) You must be a certified practitioner in order to administer and interpret the inventory. This is done via the publisher and seeks to prevent the colloquial chatter about the assessment as seen in this thread.\n\n3) The scored results of the assessment are shown on what the publisher calls a \"preference clarity index.\" I saw some comments that complain that assessment lumps you into categories. This is a bit of a misnomer. The clarity index measures how clearly you align to the specific dichotomies, not whether you're E/I, T/F, etc.\n\n4) Many of you are isolating the science from the theory, which for MBTI can lead to a lot of... well, what's being discussed here. In a nutshell, the theory is that everyone has innate preferences that should not change over time - physical examples of being right vs. left handed, etc. However, everyone can flex into different preferences throughout life given environmental variables. \n\ntl;dr: don't try to interpret MBTI if you're not certified. It's an inventory not a test. Understand the theory before dissecting the science.\n\nEDIT: spelling",
"I have found that everyone is saying there are plenty of test better than Myers-Briggs but I keep on seeing people post tests that have to be paid for and administered.\n\nA lot of people who start looking at this are trying to better understand themselves and would love to do better ones but as soon as you want to give one that had to be paid for, well. That is about it.\n\n",
"Your question is leading. For a start MB isn't really a personality test, but a way of showing your preferences for taking in and dealing with information. The beauty of it is its simplicity and the ease in which people can understand it.\n\nThe vast majority of people will (if they answer honestly) be correctly typed and patterns of behaviour are easily recognizable between people of the same type. In my experience its extremely difficult for someone to 'break the mold' of their type and tend to readily conform.\n\nSo, if what you mean by valid is 'are the types an accurate reflection of reality?' then yes it is. If you are asking if a free online test is 100% accurate then the answer is no.\n\nHowever, its kind of self-evident. If someone enjoys dancing on stage in front of loads of people then you might be tempted to say they are extroverted and living in the moment. Alternatively, if someone likes working on complex abstract problems on their own or in small groups then you might say they are an introverted thinker. Its no wonder that most scientist fall into this second category and most performers fall into the first.",
"Adam M Grant did a good write about it here:\n[Say Goodbye to MBTI, the Fad that Won't Die](_URL_0_?)\n\nBut I really appreciate the specific citations done by the top comment here.",
"I wish I could answer this questions but as a psych major who took 5 years to graduate with a 2.3 gpa and is now selling industrial boiler safety valves I pretty much forgot everything I learned about psychology ",
"Most of the criticisms mentioned here have talked about the Myers Briggs test specifically so I thought I would bring up some more general ideas criticisms that may interest you\n\n- Is the concept of 'personality' scientifically valid? Does it have an objective scientific existence, independent of culture? What are its assumptions, what does the existence of personality predict, do these things hold true? \n\n- Are the measurement methods used in personality research valid? Are personality treats measurable quantitatively? Typical measurement methods in personality research include techniques such as the likert scale - individuals must choose a response (strongly disagree, disagree, neutral, agree, strongly agree, etc) which are then assigned a number, and all added up to produce the final score. This treats an ordinal scale as an interval scale, violating basic mathematical principles. A good starting point for this sort of argument might be Joel Michell's \"Is Psychometrics Pathological Science?\"",
"As many others have commented here, the most compelling evidence against the Myers-Briggs Type Indicator is its unreliability. \"The Myers-Briggs test is not much more reliable than measuring body fluids; one study found that fewer than half of respondents scored as the same type a mere five weeks later. and there is little evidence that knowledge of a person's type reliably predicts behavior on the job or in relationships.\" \n\nC. Wade, & C. Tavris., (2012). Invitation to psychology, 5th edition. Prentice Hall. Saddle River, NJ. [ISBN-13:978-0-205-03519-9]\n\n\nHere is a link to some of the more psychometrically valid & reliable personality inventories, although they may not be considered the best in the field they are free! \n\n_URL_0_"
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"http://projects.ori.org/lrg/PDFs_papers/Goldberg.Am.Psych.1993.pdf",
"http://jenni.uchicago.edu/Spencer_Conference/Papers%202010/Funder_1991_Global%20Traits-%20A%20Neo-Allportian%20Approach%20to%20Personality.pdf"
],
[
"http://epublications.bond.edu.au/cgi/viewcontent.cgi?article=1026&context=hss_pubs&sei-redir=1"
],
[],
[],
[],
[
"http://en.wikipedia.org/wiki/Jungian_cognitive_functions"
],
[
"http://gom.sagepub.com/content/24/1/28.short",
"http://people.tamu.edu/~mbarrick/Pubs/1991_Barrick_Mount.pdf",
"http://myweb.usf.edu/~jdorio/ORM/Judge,%20T.%20A.,%20Heller,%20D.,%20%26%20Mount,%20M.%20K.%20(2002).pdf"
],
[
"http://www.amazon.com/Psychoanalytic-Diagnosis-Second-Edition-Understanding/dp/1609184947",
"http://en.wikipedia.org/wiki/Attachment_measures",
"http://www.reddit.com/r/askscience/comments/1p2cki/how_scientifically_valid_is_the_myers_briggs/ccy64qe"
],
[],
[],
[],
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"http://www.darionardi.com/webcv.html",
"http://youtu.be/MGfhQTbcqmA"
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"https://www.linkedin.com/today/post/article/20130917155206-69244073-say-goodbye-to-mbti-the-fad-that-won-t-die"
],
[],
[],
[
"http://ipip.ori.org/newMultipleconstructs.htm"
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z8yuj | we name hurricanes, so why don't we name earthquakes? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/z8yuj/eli5_we_name_hurricanes_so_why_dont_we_name/ | {
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"I guess a hurricane will hang around for a while and will move all over the country, so there needs to be a name that people can refer to, to warn others.\n\nWith an earthquake, it comes and it goes within seconds. No need to name it because only one place will be effected, and for a relatively short time period.",
"Because sometimes there is more than one hurricane occurring at a given time, and naming them keeps them organized. Also, it can take weeks for a hurricane to become dangerous and naming them helps us keep track. Earthquakes happen quickly, we don't get to track them. By the time we'd named them, they would be over."
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aumnf3 | - why is not vaccinating children, not an arrest-able offence? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aumnf3/eli5_why_is_not_vaccinating_children_not_an/ | {
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"It’s recently new, and it needs to be a bigger threat than it is now before the police can be involved.",
"No government, anywhere, should have the authority to force medical procedures or medicines on anyone, especially those too young to consent. I'm not antivax, but no one has the right to make decisions for you in regards to raising your children. Let the dumb ones die by their own hand. "
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2a0rn4 | why will only drugs and mechanical stimulus revive a flat-lined heart, versus a defibrillator? | I've searched, and everything I've found explains that once a heart has stopped beating, defibrillators will NOT help, but not why it won't help. I'd think an electrical boost would help. So, why is it that only a shot of adrenaline (or some other drug, potassium or something?) has a chance of bringing back a heart that has flat-lined?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2a0rn4/eli5_why_will_only_drugs_and_mechanical_stimulus/ | {
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"Defibrillators stop fibrillation, or the uncoordinated contraction of heart muscles. It doesn't start the heart beating, rather it *stops* the beating so it can resume proper timing. That makes the pumping action start working rather than just twitching."
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ft9pn0 | How do hand sanitizers work? (in chemistry terms) | I'd like to know how that magical -OH group gets rid of viruses and bacteria so easily, and how does its action compare to just soap and water. | askscience | https://www.reddit.com/r/askscience/comments/ft9pn0/how_do_hand_sanitizers_work_in_chemistry_terms/ | {
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"It's not really like soap and water. But has some of the same end results.\n\nSaponification yields polar molecules capable of micellars formation which results in dirt and microbes being surrounded and washed away while polar molecules can also break apart phospholipid membranes and cause cellular damage.\n\nAlcohols generally have two covalent bonds that contribute to polarization, which means they can also be very disruptive to a phospholipid membrane but because it is an organic solvent, it easily dissolves many other organic substances, is soluble in water because of its polarity, and can aggressively crenate microbes and cause lysis.\n\n_URL_0_\n\n_URL_1_\n\nAlso look up protein denaturation."
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2cx19a | there's hundreds (and probably thousands) of different beautiful gemstone minerals here in the world - why does it seem like diamond is the only one sought after for aesthetical purposes in jewelry? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2cx19a/eli5_theres_hundreds_and_probably_thousands_of/ | {
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"They're not, they're preferred because they have a great marketing agent! (De Beers) \n\nMy wife's ring has a diamond flanked by 2 pink topaz :)",
"_URL_0_\n\nI dont like to just spam what someone else wrote but the whole article is great, and it really details it very well. Below is the \"worth\" part of the Article By: Rohin Dhar.\n\nBefore 1870, diamonds were very rare. They typically ended up in a Maharaja’s crown or a royal necklace. In 1870, enormous deposits of diamonds were discovered in Kimberley, South Africa. As diamonds flooded the market, the financiers of the mines realized they were making their own investments worthless. As they mined more and more diamonds, they became less scarce and their price dropped.\n\nThe diamond market may have bottomed out were it not for an enterprising individual by the name of Cecil Rhodes. He began buying up mines in order to control the output and keep the price of diamonds high. By 1888, Rhodes controlled the entire South African diamond supply, and in turn, essentially the entire world supply. One of the companies he acquired was eponymously named after its founders, the De Beers brothers.\n\nBuilding a diamond monopoly isn’t easy work. It requires a balance of ruthlessly punishing and cooperating with competitors, as well as a very long term view. For example, in 1902, prospectors discovered a massive mine in South Africa that contained as many diamonds as all of De Beers’ mines combined. The owners initially refused to join the De Beers cartel, joining three years later after new owner Ernest Oppenheimer recognized that a competitive market for diamonds would be disastrous for the industry:\n\nCommon sense tells us that the only way to increase the value of diamonds is to make them scarce, that is to reduce production.\n\nHere’s how De Beers has controlled the diamond supply chain for most of the last century. De Beers owns most of the diamond mines. For mines that they don’t own, they have historically bought out all the diamonds, intimidating or co-opting any that think of resisting their monopoly. They then transfer all the diamonds over to the Central Selling Organization (CSO), which they own. \n\nThe CSO sorts through the diamonds, puts them in boxes and presents them to the 250 partners that they sell to. The price of the diamonds and quantity of diamonds are non-negotiable - it’s take it or leave it. Refuse your boxes and you’re out of the diamond industry.\n\nFor most of the 20th century, this system has controlled 90% of the diamond trade and been solely responsible for the inflated price of diamonds. However, as Oppenheimer took over leadership at De Beers, he keenly assessed the primary operational risk that the company faced:\n\nOur only risk is the sudden discovery of new mines, which human nature will work recklessly to the detriment of us all.\n\nBecause diamonds are “valuable”, there will always be the risk of entrepreneurs finding new sources of diamonds. Although controlling the discoverers of new mines often actually meant working with communists. In 1957, the Soviet Union discovered a massive deposit of diamonds in Siberia. Though the diamonds were a bit on the smallish side, De Beers still had to swoop in and buy all of them from the Soviets, lest they risk the supply being unleashed on the world market. \n\nLater, in Australia, a large supply of colored diamonds was discovered. When the mine refused to join the syndicate, De Beers retaliated by unloading massive amounts of colored diamonds that were similar to the Australian ones to drive down their price. Similarly, in the 1970s, some Israeli members of the CSO started stockpiling the diamonds they were allocated rather than reselling them. This made it difficult for De Beers to control the market price and would eventually cause a deflation in diamond prices when the hoarders released their stockpile. Eventually, these offending members were banned from the CSO, essentially shutting them out from the diamond business.\n\nIn 2000, De Beers announced that they were relinquishing their monopoly on the diamond business. They even settled a US Antitrust lawsuit related to price fixing industrial diamonds to the tune of $10 million (How generous! What is that, the price of one investment banker’s engagement ring?). \n\nToday, De Beers hold on the industry supply chain is less strong. And yet, price continue to rise as new deposits haven’t been found recently and demand for diamonds is increasing in India and China. For now, it’s less necessary that the company monopolize the supply chain because its lie that a diamond is a proxy for a man’s worth in life has infected the rest of the world.\n\nConclusion:\n\nWe covet diamonds in America for a simple reason: the company that stands to profit from diamond sales decided that we should. De Beers’ marketing campaign single handedly made diamond rings the measure of one’s success in America. Despite its complete lack of inherent value, the company manufactured an image of diamonds as a status symbol. And to keep the price of diamonds high, despite the abundance of new diamond finds, De Beers executed the most effective monopoly of the 20th century. Okay, we get it De Beers, you guys are really good at business! \n\nThe purpose of this post was to point out that diamond engagement rings are a lie - they’re an invention of Madison Avenue and De Beers. This post has completely glossed over the sheer amount of human suffering that we’ve caused by believing this lie: conflict diamonds funding wars, supporting apartheid for decades with our money, and pillaging the earth to find shiny carbon. And while we’re on the subject, why is it that women need to be asked and presented with a ring in order to get married? Why can’t they ask and do the presenting?\n\nDiamonds are not actually scarce, make a terrible investment, and are purely valuable as a status symbol.\n\nDiamonds, to put it delicately, are bullshit."
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68g1dx | Did the Rangers fought in Europe after D-Day? | Recently I read "The longest day " of Cornelius Ryan and i saw that the rangers assaulted the Pointe du Hoc and Omaha Beach. After the assault did the Rangers participate in the European Theater?
Did some of you know some good books about the assault in omaha beach and the ranger story during ww2? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/68g1dx/did_the_rangers_fought_in_europe_after_dday/ | {
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"Yes. After D-Day, the 2nd Ranger Battalion took part in the Battle for Brest in September 1944, the Battle of the Hürtgen Forest in December 1944, and the Battle of the Bulge in December 1944 and January 1945. They then participated in the crossing of the Roer River and advanced into Germany in early 1945. The 5th Ranger Battalion took part in D-Day as well as the fighting at Brest, but was transferred to the U.S. Third Army in the Lorraine and Saar areas for a short time in fall 1944 before entering combat in a defensive role on the very southern flank of the German Ardennes offensive. In February and March 1945, the battalion aggressively entered Germany and then assumed military government duties.\n\n**Battle Casualties of 5th Ranger Battalion During Operations:**\n\nOperation|KIA|WIA|MIA\n:--|:--|:--|:--\nNormandy|23|89|2\nNorthern France [Brest]|25|130|2\nRhineland [Lorraine/Saarland]|18|106|5\nRhineland [Irsch-Zerf]|34|140|12\n\nThe 1st, 3rd, and 4th Ranger Battalions, part of the 6615th Ranger Force (Provisional), were destroyed during the calamitous [Battle of Cisterna](_URL_2_) in Italy in late January 1944. The remains of the three battalions were later deactivated at varying dates in 1944. The 6th Ranger Battalion served in the Philippines from October 1944 until the end of the war, taking part in the raid on the Cabanatuan prison camp in January 1945, which freed over 500 American prisoners thay had been held there since the Bataan Death March of 1942.\n\n**Sources:**\n\n[Ranger Battalion Histories](_URL_0_)\n\n[Ranger Battalion Histories II](_URL_1_)"
]
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"http://www.wwiirangers.com/index%20pages/history.htm",
"http://www.ranger.org/resources/Documents/Ranger%20History.pdf",
"http://www.flashman.com/Cisterna.htm"
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|
3l51bk | why do most businesses use ups or fedex instead of the us postal service. | As above, they both seem like pricier options for the same quality of service. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3l51bk/eli5_why_do_most_businesses_use_ups_or_fedex/ | {
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"In general, for packages you can get better prices from UPS or FedEx than you could from the USPS. For letters, sure, the USPS is best, but for packages? Depending on how fast you need it delivered, they aren't usually the best choice.\n\nSource: Worked shipping/receiving for years",
"On another note ups and fedex also ship stuff usps won't. Lots of hazardous things can not go through usps"
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3kqhuw | Why is the maximum to the graph of y=x^x equal to e? Is this how e was determined? | The graph starts looking something like y=sqrt(x) between x=0 and x=e, but after e is reached on the x-axis (e, ~1.44) it looks like y=1/x, why is this? Why is e the turning point? Why does it approach 1 but never reach 1?
EDIT: I meant x^1/x, not x! | askscience | https://www.reddit.com/r/askscience/comments/3kqhuw/why_is_the_maximum_to_the_graph_of_yxx_equal_to_e/ | {
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"The derivative of y=x^x is dy/dx=(1+ln(x) )x^x . You can show this by differentiating the logarithm of both sides of y=x^x .\n\nFor this to be zero, ln(x) has to be equal -1, which means x is e^-1 (e is 2.78..., not 1.44). The value of the function at x=1/e is (1/e)^(1/e) which is .69. This is also the minimum, and not the maximum. Maybe you're thinking of x^-x ?",
"I think you mean x^(1/x), which has derivative x^(1/x)(1-ln(x))/x^2 which is zero when x=e since 1-ln e=1-1=0.\n\nWe have (1-ln(x)) > 0 for x < e and (1-ln(x)) < 0 for x > e while x^(1/x)/x^(2) > 0 so the derivative is positive to the left and negative to the right. Hence, x=e is a local maximum for x^(1/x).",
"We're clearly talking about y=x^(1/x) here. The maximum has been answered. So why doesn't it go down below 1? Well, raising something to the power 1/x is taking the x-th root. For numbers larger than 1, the x-th root is larger than 1, so it can never drop below 1.\n\nAlternatively: x^1/x = e ^ (ln(x)/x). ln(x) grows slower than x, so the power term will go to 0, hence x^1/x will go to 1."
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6o5vvs | on many reality shows like bar rescue, they often find extreme health hazards like cross-contamination, mold, rotten meat, etc. how do these restaurants/bars/hotels not get shut down by the usda? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6o5vvs/eli5_on_many_reality_shows_like_bar_rescue_they/ | {
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"The USDA isn't the agency that shuts down bars/restaurants. It's the county health department.\n\nSome of these departments inspect infrequently, so there's a lot of time to get scuzzy since the last inspection. Some are even corrupt, and will accept a bribe to give a passing grade."
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1w8suo | If Cowpox was used to create the smallpox vaccination, then why isn't FIV used to create an HIV vaccine? | askscience | http://www.reddit.com/r/askscience/comments/1w8suo/if_cowpox_was_used_to_create_the_smallpox/ | {
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"Smallpox, or the variola major virus, is extremely similar to all the other relatively benign viruses in its genus. The genus \"orthopoxvirus\" also contains cowpox, vaccinia, monkeypox, camelpox, etc. all of which infect mammals. It is known that vaccination with cowpox provides protection from smallpox, but also the more modern vaccine with vaccinia provides protection from smallpox and monkeypox. This is because all of the viruses in the genus are genetically similar in many ways, which is largely due to the relatively slow rate of mutation. \n_URL_0_\n\nRetroviruses like HIV, on the other hand, mutate rapidly. Once the human immune system makes antibodies to HIV, the virus can rapidly evolve to counter this. Closely related viruses like SIV or FIV, then, are much more genetically diverse relative to poxvirus species. The mutation is so rapid within one individual, this means you not only can't vaccinate with SIV against HIV, but you also can't vaccinate with HIV against HIV! \n\nTo add to this, retroviruses only have a couple virus proteins on the virus surface, while poxviruses have over 20 virus surface proteins. Thus, poxviruses have many targets the immune system can react against, while retroviruses can easily mutate the few surface proteins they have to counter the immune system's adaptive response."
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ctcsp6 | Why was the number 299,792,458 chosen as the definiton of a metre instead of a more rounded off number like 300,000,000? | So a metre is defined as the distance light travels in 1/299,792,458 of a second, but is there a reason why this particular number is chosen instead of a more "convenient" number?
Edit: Typo | askscience | https://www.reddit.com/r/askscience/comments/ctcsp6/why_was_the_number_299792458_chosen_as_the/ | {
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"The principle was to keep the definition consistent with previous measurements, within their uncertainty. We already had a definition for the metre, just not as precise as the current definition, and we want the new definition to be as consistent as possible, but just easier to measure precisely. Rounding to 300,000 km/s would change the definition of the metre by about 0.07%. That would just make life different for everybody: we'd have to specify if we're talking about the \"old\" metre or the \"new\" metre, because that 0.07% change is big enough to matter. It'd change the circumference of the Earth by about 30 km, for instance - a big enough difference that it's measurable, even if it's small.\n\nRounding down to the nearest 1 m/s means that instead of a 0.07% change, the change is ~0.0000003% at most. So, that changes the circumference of the Earth by < 10 cm at most. That's small enough that it would typically be within the measurement error, and it's close enough that we can treat the metre as unchanged without causing any problems.",
"The meter ~~is~~ was defined as 1/10,000,000 the distance from the equator to the North Pole at the longitude of Lyon.\n\nThen people figured out that this wasn't a great way of developing a precise unit of length due to difficulty measuring, and the fact that the value might even change due to Earthquakes, and it could only be referenced at one spot (the line through Lyon) and they searched for a definition that was a universal constant. Eventually the speed of light was chosen (there were electrum rod references in between), and it happened to be 299,792,458. It's a pure fluke that it's so close to 300,000,000",
"The goal was to define the meter using constants, not redefine the meter itself. So, the people who defined it said \"how long does it take light to travel one meter in a vacuum?\" and did the math. Light will travel that distance anywhere in the Universe, so the definition is now not subject to change unless we are measuring the speed of light incorrectly. If we used some other metric, like a distance on Earth, that distance is subject to tectonic adjustments and is not quite as constant, plus it can't be derived on other planets (not that that matters right now).",
"If we stick to strict mathematics, then nearly nothing is as simple as a \"well rounded whole number\". Its convenient for us and it's what we usually do when it doesn't have to be an exact measurement, but usually those few digits off mean something failing or not.",
"The meter was originally defined in the late 18th century as 1 / 10 000 000th of the distance between the equator and the north pole. The definition as a fraction of a light year was later adopted in 1983 so it would depend on a constant.",
"It sure beats the previous definition, where 1 metre was equal to the length of \"this stick\".\n\nBy redefining our SI units in terms of universal constants, someone can recreate them without ever having to used the original physical representations.",
"This number wasn't \"chosen\" but was rather formulated by James Maxwell's laws of electromagnetism. The number essentially comes from the speed that an electromagnetic wave travels at and that's derived from some constants that have been used elsewhere so that's what nature's given us. It also paved the way for special relativity etc",
"This number was not chosen. A metre is a specified distance. It is done to keep the physics logical. Acting against a force of 1 Newton through a distance of 1 metre will require 1 joule of energy. \n\nThis is now a fixed distance. \n\nLight will traverse this distance in some amount of time, which you have stated.",
"They did choose the more convenient one. \n\n They cared less about keeping the number of seconds nice and even, and more about keeping the length of a meter to as close as what it is now as possible. There was no reason to define the length of a meter and change it dramatically if all you would be doing is changing the number if seconds that define the unit.",
"It's because it's a retro-active definition. We already have the meter and use it, and have used it since well before we knew what the speed of light is. Now we need an always-consistent definition for scientists to use, so we're gonna arbitrarily decide to measure how much time it takes for light to travel a meter. And then we'll use that as the new definition of the meter.",
"You're thinking of the modern method of measuring a metre by the distance light travels in a certain time. That was done for accuracy, but really it is a conversion of the previous method of measurement which is what a meter is derived from, which is a unit of measure based off a naturally occuring increment here on earth. The number you listed is just the updated version of that number.",
"Aside from the more nuanced explanations about the nature of the metre, once you get beyond the kind of measurements humans needs for their day to day lives *(where it actually matters if calculations are quick and sums easily sub-dividable)* it becomes far more trouble than it's worth to worry about having \"convenient\" numbers. \n\nExperts in their fields will simply *know* what certain measurements and calculations are/should be and will seldom *need* to calculate anything in the field or they may even be working with theories/systems/equations that simply factor in or don't need the more complex mathematics...\n\nEven so, dragging things around to make any number more convenient would have the adverse effect of making everything *else* more complicated. \n\nIn math/science, fudging the \"truth\" because it's convenient or to fit a preconceived notion or aesthetic is practically the worst thing you can do.",
"I've read a lot of the responses here and I think it can be summed up thus:\n\nIf we had managed to measure the speed of light first, then it would have been a more convenient number. The original definitions of just about all measurements were convenient at first, until we got accurate enough to realize how malleable those definitions are and tried to find a more constant, yet accurate definition and wound up where we are.",
"Because the speed of light in a vacuum is 299,792,458 meters per second. The meter had defined length before that, so rather than redefining the speed of light and the meter, it was decided to use the speed of light, a physical constant, to define the meter."
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67dcsm | how is it that an airplane can take off even if it's on a treadmill that matches it's speed? i understand that mythbusters proved that it will take off, but i don't understand how? | Can someone explain what happens to
1. Position of the plane relative to ground.
2. Speed of wheels.
3. Speed of conveyor belt.
The thing is, I can imagine the conveyor belt moving the plane backwards at 5 mph. Then the plane adds thrust, so it's moving 0 mph. Then the conveyor belt moves 10 mph. That's -5 mph. Then the plane adds thrust, so it's moving 0 mph. At what point does this logic break down?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/67dcsm/eli5_how_is_it_that_an_airplane_can_take_off_even/ | {
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"An airplane's wheels aren't (normally) powered. All the thrust comes from the props/jets \"pulling\" on the air. The wheels just spin freely; there is some backwards drag from the treadmill but not enough to completely counteract the thrust of the engine.\n\nNow if the plane were in a wind tunnel, that would be a different story. The plane would still technically \"take off\" because its wings would give it lift, but it couldn't move forward.",
"Um. I don't think thats how it works - can you link to the MythBusters episode that shows it working?\n\nAirplanes can take off when the _airflow_ across/under their wings reaches a certain speed. Period. The speed that their wheels are travelling on a treadmill has nothing. to. do. with. it. Unless there's an external factor providing airflow to the wings to generate lift. \n\nNever mind. [Found it.](_URL_0_). \n\n1. the airplane in question has a ridiculously low take off speed. Its a brush plane designed to take off at low weights and speeds.\n\n2. the truck is towing the conveyor belt backwards. \n\n3. the conveyor belt, which is moving backwards at the same speed the aircraft is moving forward.... all that means is that as soon as the airplane's wheels hit the conveyor belt, they're now moving _twice_ as fast as the airplane is moving forward. \n\nThe key bit is how fast is the propeller pulling the aircraft forward relative to the air. Which remains unchanged regardless of how fast its wheels are moving forwards or backwards on the conveyor belt. ",
"The wheels and the ground are not important for a airplane regarding flight. Airplane can have wheels, skids or pontoons. Their only function is to make it easy to move over the ground they are not use for any energy transfer. \n\nThe importerat thing it the speed the aircraft has relative to the air. A propeller/jet engine pushes against the air and the is the thing used to accelerate the aircraft the ground and wheels are not involved\n\nSo if the ground move backward the only effect that would have is that the wheel would have to spin faster. The wheel spinns free like the front wheel on a bike. As long as the wheels can stand the spins the speed of the ground want matter because not energy is transferred to the aircraft.\n\nAnother way to see that the round speed is irrelevant is that high winds can cause a airplane to start to fly. The stall speed of a smal Cessna is 40 knots and a storm wind speed is above 48 knots so in high wind a small aircraft might might start to fly while being stationary relative to the ground.\n\n\n\n",
"Another way to think about it which might help is that the wheels can be spinning in any direction, at any speed, and an airplane can still take off because the ground is largely irrelevant. The engines are pushing off the air, the ground is just there to prevent the plane from falling into the center of the earth."
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a6dhv7 | which lubrication to use when? | I'm confused. There's regular oil, silicone oil, WD-40, petroleum jelly and graphite powder. I have zero idea how to decide which one to use for what application. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a6dhv7/eli5_which_lubrication_to_use_when/ | {
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"When you hit a problem where you need lubricant Google what you need. I can tell you the WD40 is a penetrating releasing lubricant, meaning it's good at getting stuck things unstuck. Graphite power is a dry lubricant meaning it's going for things like locks where you really don't want to get it gunked up with dust and crap that will otherwise stick to a wet lubricant. The others, I'm less sure about.",
"Depends on the item and context. Also, no such thing as \"regular\" oil - Different lubricants have specific features and uses, and equipment has unique needs for lubrication - viscosity, additives, corrosion inhibitors, that sort of thing. \n\nCar oil - in your car engine to lubricate and cool bearings. look up the correct grade (usually an SAE number like 5w-30, where the w indicates the winter grade) to match with the engine manufacturers specs. Not for sex. \n\nSilicone oil - specifically for use with silicone items, usually sex toys. Don't use with anything not silicone. Don't use any other lubricant on silicone items either. Possibly for sex. \n\nWD-40 - heaps of uses! The wd stands for water displacer, so it's good to use as a light corrosion inhibitor, but will need frequent reapplication. Don't use it to lube bike chains as it can damage the bearings. Not for sex. \n\nPetroleum jelly - heaps of uses, it's also known as white Vaseline. I use it on seals in hydraulic and fuel systems. Not for sex.\n\nGraphite powder - a dry lube for small intricate machinery like locks, or in high heat areas where a conventional lubricant would dry out. Can also be found mixed in liquid, and is then called \"colloidal graphite lubricant\" as the liquid is just there to help apply it faster and more evenly. Not for sex. "
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5heh5j | working class opposition to unions. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5heh5j/eli5_working_class_opposition_to_unions/ | {
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"In many cases it simply comes down to fear. For example, my father's place of employment tried to unionize. Management started rumors that they wouldn't be able to afford it if a union came in and would have to shut the sawmill down.\n",
"* Unions take money out of your paycheck (to pay for their services, of course, but like insurance people who don't think they benefit from the service resent the payment)\n\n* Unions prevent people from getting jobs, because if unemployment is high union shops hire unemployed union workers first, thus making unions appear to be nepotism instead of hiring the most qualified. (well, of course unions are designed to help their members, but can leave a bad taste in people's mouths)\n\n* Unions make it difficult to fire or correct undesireable employees, which can feed into toxic workplaces (i.e. police officers that seem obviously corrupt or lawbreaking being defended by the police unions)\n\n* Unions make decisions on your employment on your behalf, rather than allowing the individual to make their own decisions for themselves, removing independence in negotiating raises, perks, etc., so it seems anti-freedom.\n\n"
]
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[],
[]
] |
||
3fxpzd | how can scientists conclude results similar to "doing x increases chance of cancer by 15%" | Im not a science geek but I know my fair share of it. How can a scientist identify a control group such that it will yield results as mentioned in question? If thats not the case then how realistic are those statistics? Especially when a condition such as cancer which devolops in long long time is the case
Edit: forgot the question mark so here it is "?". | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3fxpzd/eli5_how_can_scientists_conclude_results_similar/ | {
"a_id": [
"ctsy1hv"
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"score": [
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"text": [
"The answer is they use multiple regression analysis and very large and hopefully well chosen samples. This should weed out the correlations. For example women with breast implants get cancer more often, but women with breast implants also smoke and drink more and do other things that increase cancer risk. So by using multiple regression and a large, well chosen sample you sort out the real connections from the correlations.\n\nOf course getting a large sample is expensive and getting a well chosen sample is expensive and takes some skill. You also have to put the variables for possible correlations into the analysis so anything unsuspected will slip through. Its not a perfect situation."
]
} | [] | [] | [
[]
] |
|
mnn31 | AskScience, I am so tired of newspapers turning every piece of scientific news into sensationalist bullshit. Can you recommend me a news source that tells it as it is? | I know about specialized scientific journals, but I want something lighter, where they actually read the important scientific paper in question, understand it, and write an article about it for the general audience. | askscience | http://www.reddit.com/r/askscience/comments/mnn31/askscience_i_am_so_tired_of_newspapers_turning/ | {
"a_id": [
"c32d9y4",
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"text": [
"physorg and sciencedaily.\n\nlighter than a journal, several reading levels above a newspaper.",
"physorg and sciencedaily.\n\nlighter than a journal, several reading levels above a newspaper."
]
} | [] | [] | [
[],
[]
] |
|
bc958t | Ionic compounds dissociate in water due to the positively charged components and negatively charged components being "pulled apart" due to their attraction to the polar water molecules. But how are organic, non-polar compounds "dissolved?" | There are no partial charges on the solvent to attract and therefore "pull apart" the solute. Are these compounds simply enveloped by the solvent? This has always confused me whenever classes discuss "like dissolves like".
If anyone could clarify I'd appreciate it! I don't want to ask any profs this potentially stupid question | askscience | https://www.reddit.com/r/askscience/comments/bc958t/ionic_compounds_dissociate_in_water_due_to_the/ | {
"a_id": [
"ekpzscs"
],
"score": [
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],
"text": [
"There are indeed no partial charges in non-polar organic compounds, but there are transient \"redistributions\" of electron density that lead to favourable short-range interactions between solutes and solvents -- Van der Waals forces. \n\nSolubility is all about what balance of forces leads to a lower-energy system. Ionic compounds dissolve in water when the energetic balance between being in a solid (generally crystalline) form vs. being solvated by polar water molecules tilts toward the latter. With organic compounds it's the same situation, except the solvation comes from Van der Waals forces rather than polar interactions."
]
} | [] | [] | [
[]
] |
|
7fx5xc | why are some sounds annoying when they're made by others but satisfying when we make them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7fx5xc/eli5_why_are_some_sounds_annoying_when_theyre/ | {
"a_id": [
"dqeyqug"
],
"score": [
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"text": [
"Liking unusual sounds is usually just you being satisfied that you know how to make the sound. When others hear it, they don't know the cause, and it feels odd to them, even after they see where it's coming from. So when they try it, they are satisfied that they're able to make a similar noise, like it's some type of achievement. Another reason is simply because only you might understand it or relate it to something good. If I'm bored and try to tap to the Harry Potter theme song or Flight of the Bumble Bee, every \"stroke\" I make is monotone. I know what song I'm \"playing\", but it's actually very difficult for someone else to figure out what you're playing. Just imagine tapping FotBB, you'll look like a freaking spaz"
]
} | [] | [] | [
[]
] |
||
41ehhm | what's currently happening with michigan's water and why? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/41ehhm/eli5_whats_currently_happening_with_michigans/ | {
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"In Flint, MI (not the entire state) almost 2 years ago, the powers that be decided to stop using Lake Huron (via Detroit) as its water source and switch to using the Flint River, which to those who grew up in or around Flint is utterly laughable because it's a notoriously brown, murky, polluted mess, but I digress. The switch was done in order to cut budget costs, so to save a little money basically. \n \nSoon after the switch, residents noticed their water looking and smelling funny and dirty, apparently due to the high amount of iron in water from the Flint River which makes this water 19 times more corrosive than the clean, clear miraculous inland ocean of tasty wonder that is Lake Huron's water. The State Department of Water Equality didn't add anti-corrosive agents to the water, so the water was eroding the pipes carrying the water to everyone. The lead poisoning experienced is a result of that, lead in the piping infrastructure being corroded by the shitty water. Basically, Flint city water will not be safe again until they complete replace the infrastructure that's been irreparably damaged. \n \nNow, people are trying to get as much bottled water to Flint as possible, with grocery stores all over the state taking donations from cool people who buy extra packs of bottles to be sent to the city. But it's really only a drop in the bucket. People need/use an astonishing amount of water on a daily basis. Meanwhile, officials are telling people the water is safe, though to what degree I'm not 100%. (In other words, I'm not sure if the water has been OK-ed to drink or if they say it's just okay for bathing and washing dishes, etc.) I'm sure someone living in Flint now could elaborate more about their personal experiences. \n \n[source with more info](_URL_0_)",
"Various cities in Michigan have been struggling mightily with their budgets. Some cities were in so much financial trouble that the Governor began appointing Emergency Managers. This was legal.\n\n_URL_4_\n\nAn Emergency Manager (EM) is effectively a dictator. They can remove staff, change spending and otherwise redirect and reshape resources with no accountability to local government or citizens. Flint's City Council and their EM decided in March 2013 that Flint could save money by drawing its drinking water from Lake Huron instead of buying it from Detroit. Detroit didn't appreciate this and notified Flint that it would cut them off on April 17, 2015, before Flint was anywhere close completing their new pipeline. In late April 2014 Flint's EM decided to draw and treat water from the river. Untreated river water is more corrosive/reactive than treated water and it began to leech lead from the pipes and from the lead solder used to join the pipes. Apparently the treatment was too dilute or was otherwise performed ineffectively.\n_URL_0_\n\nLast October 15, Flint switched back to Detroit's water supply. That's 17 months of Flint's citizens experiencing unmonitored exposure to lead-contaminated water. All they were told by the city was to boil the water and they would be fine. According to the CDC, boiling lead-contaminated water can increase exposure.\n_URL_2_\n\n > Heating or boiling your water will not remove lead. Because some of the water evaporates during the boiling process, the lead concentration of the water can actually increase slightly as the water is boiled.\n\nHere is The Rachel Maddow Show's first coverage of the scandal, broadcast December 15. She does an excellent job of clearly explaining what is happening and what lead up to it.\n_URL_3_\n\nYou can see all of her coverage in these clips: _URL_1_"
]
} | [] | [] | [
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"http://www.cnn.com/2016/01/11/health/toxic-tap-water-flint-michigan/"
],
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"https://en.wikipedia.org/wiki/Flint_water_crisis",
"http://www.msnbc.com/search/maddow%20flint%20lead",
"http://www.cdc.gov/healthywater/drinking/private/wells/disease/lead.html",
"http://www.msnbc.com/rachel-maddow/watch/towns-water-toxic-despite-state-assurances-588539459955",
"https://en.wikipedia.org/wiki/Financial_emergency_in_Michigan"
]
] |
||
2kgbe2 | Are all antioxidants equal in effectiveness? | . | askscience | http://www.reddit.com/r/askscience/comments/2kgbe2/are_all_antioxidants_equal_in_effectiveness/ | {
"a_id": [
"clm3t7u"
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"text": [
"I don't think there is much evidence for benefit of antioxidant supplements. Not all antioxidants are the same - they have differing abilities to mop up reactive oxygen species. We know that reactive oxygen species can cause damage, and antioxidants such as vitamin C and E and flavanoids can oppose these ROS. Dietary deficiency of antioxidants is bad for you, and a diet rich in antioxidant vitamins is *associated* with reduction in some diseases. But I don't know that there is benefit in antioxidant supplements for someone who has no dietary deficiency. People are doing research about these supplements all the time but I don't think there has been any great result as yet. \n\nAddit: the initial small studies showed some benefit, but larger randomised trials haven't shown benefit (at least with respect heart disease). A typical trial is like this one, \n\n[H. D. Sesso, J. E. Buring, W. G. Christen et al., “Vitamins E and C in the prevention of cardiovascular disease in men: the physicians' health study II randomized controlled trial,” Journal of the American Medical Association, vol. 300, no. 18, pp. 2123–2133, 2008.](_URL_0_). \n\nThere are others, this one in the Lancet showed some benefit with vitamin E, [Randomised controlled trial of vitamin E in patients with coronary disease: Cambridge Heart Antioxidant Study - \\(CHAOS\\)](_URL_1_)."
]
} | [] | [] | [
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"http://www.ncbi.nlm.nih.gov/pubmed/18997197?dopt=AbstractPlus",
"http://www.thelancet.com/journals/lancet/article/PIIS0140-6736\\(96\\)90866-1/abstract"
]
] |
|
3317o5 | Is there a relationship between droughts and the increased in carbon dioxide levels? | i mean can it actually increase droughts in some parts of the world due to increase greenhouse gases? | askscience | http://www.reddit.com/r/askscience/comments/3317o5/is_there_a_relationship_between_droughts_and_the/ | {
"a_id": [
"cqh0cxx"
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"The short answer is \"Yes\". When people think of global warming, most people think of temperatures rising - which isn't surprising given the name! However, the temperature increase *itself* isn't actually the biggest problem. The real, major issues are the secondary effects that rising temperatures cause, such as changes in climate systems. All climate systems on the earth rely on energy and when you change the energy inputs (e.g. by changing the temperature), you can get very complex and significant changes.\n\n[The general view is that increasing temperatures will result in an increased risk of extreme weather, including drought](_URL_0_). The climate is an incredibly complex system - some parts of the earth will get wetter - but generally speaking, climate change exacerbates existing weather trends. This means that areas that are already vulnerable to droughts are probably going to be more vulnerable in the future. \n\nThere are many reasons why drought might become more likely. Here's an example. Many areas get their water from snow melt (e.g. the regions around the Himalaya). If you increase the temperature, that snow melts earlier and more suddenly. You get an earlier surge of water and naturally, it quickly runs out, leaving you deprived of water in the summer. You may also realise that, as paradoxical as it sounds, this also increases the chance of flooding as well as drought! On top of that, the ice sources that supply these people in the first place are getting smaller, decreasing the overall supply. According to the IPCC, a sixth of the world's population depends on melt water so this is quite a big problem. \n\nIncreased greenhouse gas concentrations lead to higher temperatures which generally leads to more extreme weather and hence a higher overall risk of drought. So there is a relationship between increased CO2 levels and droughts, but it's not *direct* cause and effect."
]
} | [] | [] | [
[
"https://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch3s3-4-3.html"
]
] |
|
442dj6 | why do asian immigrants more than any other race give their child "american" names? | (With the exception of universal biblical names for example) , African immigrants will give their child an African name. Mexican immigrants will give their child a Hispanic name. Indian immigrants will give their child an Indian name. I am generalizing but mostly I see this obvious pattern. But for Asian immigrants, they'll give there child "American" names like Doug, Vince, etc. Why is that? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/442dj6/eli5_why_do_asian_immigrants_more_than_any_other/ | {
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"text": [
"A lot of the times, they don't. That's just those kids taking on the closest English approximation to their name (or just one they like best) to avoid always having to tell people how to spell / pronounce it. Most of the time, their legal name is indeed something Asian.",
"I think it has to do with the pronunciation of most Asian names. It would be very hard for Westerners to not butcher their names. I also have heard that having an Anglo-saxxon name are more competitive and better view upon when trying to gain employment in the west.\n\nAsians in general (At least the ones that were born in an anglo country) seems to assimilate really well. ",
"Many Asian immigrants already have an English-language name because their native language name is hard to pronounce or spell. It's a normal practice in several countries. Accordingly, they have no trouble giving such names to their children, though they may additionally give them a name in their native language.",
"Are you sure about the african immigrant thing? Black american names have african roots but also english roots and heavy french roots and aren't strictly traditional african names. \n\nIn general the farther away from a romance language someone's name is the more it gets changed and mangled to sound more english. ",
"This seems to be most common among Chinese people in particular. It may be because Chinese language is tonal, and it is hard to English-speakers to pronounce them properly. On, the other hand, it is pretty easy for a native English speaker to pronounce most Spanish names."
]
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[],
[],
[],
[],
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|
3o99nj | What do historians think of John Geen's Crash Course History? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3o99nj/what_do_historians_think_of_john_geens_crash/ | {
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"text": [
"Always room for more discussion, but there is [a section of the FAQ](_URL_0_) devoted to this very question. \n\nThe only episode I have seen that I am qualified to comment on is the \"Neolithic Revolution\" episode. It is far from perfect, but it certainly isn't too far from the consensus in the field at the moment. It is pretty much on par with what you can expect from a well-written textbook on the subject, which is to be expected given the huge breadth of topics covered by the series. ",
"I second the \"check the FAQ\" posts, but my overall opinion: it's not bad for a populariser of history, and if you want a basic primer on historical topics you don't know anything about. \n\nI suspect I'm not the only historian to react like this but basically, I found the episodes on topics I'm not an expert at all in to be quite interesting, while those that I do know quite a lot about seemed like ELI5 videos. Though I guess that's inevitable. Also, occasionally something he says about your specialist topics can annoy you incredibly disproportionately (my most pedantic point of irritation is his incorrect pronunciation of \"Jacobins\", for example).\n\nTo be fair to John Green, I think he learns from and tries to respond to criticism. In his second World History series, he did indeed try to incorporate more historiographical debates and conceptual analysis, and I commend him for that."
]
} | [] | [] | [
[
"https://www.reddit.com/r/AskHistorians/wiki/historians_views#wiki_historians.27_views_of_john_green.27s_.27crash_course_world_history.27"
],
[]
] |
||
6dlq0x | Why was ancient Egypt's technology lost/forgotten? Didn't they keep records? Wouldn't their techniques have been passed down through the generations? | I've been watching and listening to various documentaries and it seems like all of the great technology that the ancient Egyptians used was simply lost somewhere along the way, leaving us guessing or hypothesizing at how they did everything they did. I just don't understand how that is possible without some kind of mass catastrophe that wiped everything out. | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/6dlq0x/why_was_ancient_egypts_technology_lostforgotten/ | {
"a_id": [
"di488o0"
],
"score": [
3
],
"text": [
"Could you be more specific about which technologies were (supposedly) lost? "
]
} | [] | [] | [
[]
] |
|
2ps5zh | how can animals live in contaminated areas created as a result of a nuclear disaster, but humans can not? | Do they get affected at all or anything? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ps5zh/eli5how_can_animals_live_in_contaminated_areas/ | {
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"Plants and animals are not affected by laws, unlike humans.\n\nThat does not mean however, that most animals and plants aren't affected by the (Chernobyl*) radiation. Many species of birds and plants have evolved radiation-resistant abilities, for example by increasing the amount anti-oxidants or having more active cell repair abilities. \n\nThen again, there are also humans living within the exclusion zone. A small group of predominantly senior women lives within the exclusion zone, because they've lived there their entire lives.\n\nIn practice though, you could live perfectly safe in Chernobyl as long as you don't visit any hotspots, don't disturb the soil and trees too much, and don't eat any mushrooms.\n\n* Fukushima is too recent to gauge any of the effects. ",
"They don't live long enough to suffer the consequence of it. Just like how they don't get tooth decay from not brushing teeth. Also, I read somewhere on reddit where they said smaller animals are more resistant to radiation. It makes sense that their body is more simple than humans and so has less organs to fail.",
"Radiological contamination of this sort means that there are radioactive particles (long-lived fission products, to be specific) in the ecosystem. These materials are not so terribly radioactive that they will kill you immediately or even make you acutely ill. They are, however, radioactive enough that if you get lots of them in your body, over a long period of time, they can increase your risk of cancers over the long-term — e.g. over a horizon of several decades. And \"increase your risk\" doesn't mean \"you get cancer 100%\" — it just means that probabilistically, your risk of certain cancers (and other illnesses) will increase by a certain amount.\n\nBirds and deer don't generally live several decades. So they won't die of radiation-induced cancers, because the time of their development is too long. They do pick up radioactive particles in their bodies, which is only a problem if something more long-lived (like people) kills and eats them ([wild boar hunted in Germany now have to be screened for radiation because of Chernobyl](_URL_0_)).\n\nPeople over a certain age aren't going to die of radiation-induced cancers, either — because they're going to die of just being old, before the cancers can hurt them.\n\nSmall groups of people probably won't get cancer, because the risk factors aren't increased by so much that the excess cancers would be noticeable. So let's say that the risk increased so that 1 out of 100 people would get cancer. If only 100 people are living in one of these zones, you're not going to be able to distinguish the 1 extra cancer over the course of those lifetimes — it might not even occur, but even if it does, it is going to look pretty similar to the sources of cancer that come from other sources.\n\nThe reason that large numbers of people cannot live in these areas is because at that point you would start to see larger numbers of excess cancers, birth defects, and other side-effects of prolonged, chronic radiation exposure starting to show up in the populations. So if 100,000 people were living in that area, and the radiation increased their cancer rate by 1%, that's 1,000 new cancers — a fairly significant number. "
]
} | [] | [] | [
[],
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"http://www.nbcnews.com/news/world/chernobyl-disaster-leaves-radioactive-wild-boars-roaming-germany-n193596"
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|
15s8hr | What are the actual addiction rates of various drugs? | I had heard that alcohol has a ~10% addiction rate, but hadn't been able to find any sources to back up that claim. Then I was curious about other drugs' addiction rates - in the US, if culture matters. I found [this study](_URL_0_) which lists heroin as the most addictive drug at 13.4%. Is this a reliable study? The numbers seem INCREDIBLY low for how much fear-mongering is done, even among casual drug users regarding harder substances like heroin or crack, as well as a 3% dependence rate for alcohol | askscience | http://www.reddit.com/r/askscience/comments/15s8hr/what_are_the_actual_addiction_rates_of_various/ | {
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"text": [
"Not exactly what you asked, but you may be interested in [this article](_URL_1_), and [this looks like the actual paper](_URL_0_). It's an attempt by David Nutt et al to classify drugs by personal and social harm.",
"What do you mean by \"addiction rate\"?\n\n* What fraction of users are addicts rather than casual users?\n* What fraction of attempted quitters fail to quit?\n* What fraction of users experience significant negative effects of their use, but do not quit using?"
]
} | [] | [
"http://www.oas.samhsa.gov/2k8/newUseDepend/newUseDepend.htm"
] | [
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"http://www.fcaglp.unlp.edu.ar/~mmiller/espanol/Variedades,%20politica/drogas_Journal.pdf",
"http://www.bbc.co.uk/news/uk-11660210"
],
[]
] |
|
ej55it | I don't mean to sound insensitive, but is homophobia mostly an Abrahamic religion thing? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/ej55it/i_dont_mean_to_sound_insensitive_but_is/ | {
"a_id": [
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"text": [
"This submission has been removed because it is [soapboxing](_URL_1_.) or [moralizing:](_URL_0_) it has the effect of promoting an opinion on contemporary politics or social issues at the expense of historical integrity. There are certainly historical topics that relate to contemporary issues and it is possible for legitimate interpretations that differ from each other to come out of looking at the past through differing political lenses. However, we will remove questions that put a deliberate slant on their subject or solicit answers that align with a specific pre-existing view."
]
} | [] | [] | [
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"https://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_political_agendas_or_moralising",
"http://www.reddit.com/r/AskHistorians/wiki/rules#wiki_no_.22soapboxing.22_or_loaded_questions"
]
] |
||
2qlppw | might be a /r/shittyaskscience question, but how the fuck does shaving cream work? | what I mean is how does it expand so much? one drop of it can cover like half your face. what causes it to be so expansive? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qlppw/eli5_might_be_a_rshittyaskscience_question_but/ | {
"a_id": [
"cn78k2v"
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"score": [
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"text": [
"It's important to understand that most gasses compress very well.\n\nShaving cream is a compressed mixture of the actual 'cream' and gasses, this keeps the gas bubbles very, very small. Once you squirt it out, the gas is free to spread out and takes up many times the amount of space. This causes the cream to expand as the little bubbles inside spread out.\n\nAnother effect is the cream remaining in the can gets a bit more space to spread out and the pressure decreases. This decompression cools it down and that is why the can feels cool to the touch just after you spray some out."
]
} | [] | [] | [
[]
] |
|
131bvd | Why is the dot from a laser pointer "fuzzy?" [x-post from AskReddit] | I was messing around with a laser pointer recently and when I tried to focus my vision on the laser dot, I noticed that the area around it was kind of... fuzzy, a la television static. Why is that? | askscience | http://www.reddit.com/r/askscience/comments/131bvd/why_is_the_dot_from_a_laser_pointer_fuzzy_xpost/ | {
"a_id": [
"c6zxwn8"
],
"score": [
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],
"text": [
"It's called [speckle](_URL_0_)."
]
} | [] | [] | [
[
"http://en.wikipedia.org/wiki/Speckle_pattern"
]
] |
|
1yqj1w | how can alexa (_url_0_) find out numbers of visitors of websites (and then their rankings)? | I imagine only the owner of a website can find out how many visits his website has. How does Alexa do it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1yqj1w/eli5_how_can_alexa_alexacom_find_out_numbers_of/ | {
"a_id": [
"cfmucjt"
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"score": [
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"text": [
"It's based on their toolbar. If you have the alexa toolbar installed, your traffic is recorded and sent to alexa, which uses the statistics to rank websites.\n\nThis does make sites which are frequented by people who have a lot of browser bars installed way overrepresented though, so you should take the alexa statistics with a large grain of salt."
]
} | [
"alexa.com"
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[]
] |
|
14owua | why california's k-12 public education is so bad. | I'm a high school student and a lot of my school's sports programs were cut this year. I was just wondering why this is. Why is the education budget in California suffering from cuts? Why are so many teachers being laid off? What are some possible solution for this problem? Will the passing of Prop 30 (Raising the taxes on California's high income residents) have much of an effect at all? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/14owua/eli5_why_californias_k12_public_education_is_so/ | {
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"gate2doom summed it up pretty well. I would add that judging how successful school programs help identify how they want to allocate money. Unfortunately, kids often don't understand the long-term benefits to their education, so they don't try hard. As a result, teachers make things easier to keep grades, productivity, and moral up. In reality the better alternative may be to help students realize the value of their education more, make everything gradually harder, increased education can benefit the budget down the line. Right now many students feel like jr. High and Highschool are like day cares, and in some respects they are right. Obviously this is mostly my opinion. ",
" > Why is the education budget in California suffering from cuts?\n\n1. [Prop 13](_URL_1_).\n\n2. The [consequences of payday loan financing](_URL_0_) as the education funding source of last resort.\n\n > Will the passing of Prop 30 (Raising the taxes on California's high income residents) have much of an effect at all?\n\nBand-Aid on a bullet wound.",
"There's more than one reason. Here's an answer I provided on prop 13's effect in the past - _URL_0_\n",
"Proposition 13, 1978. \n\nIt was the beginning of the movement that has dominated American politics for over 30 years now, with disastrous consequences.",
"The California budget has a minimum percentage that must go towards public education based on Prop 98. The percentage is about 45% of the General Fund, but varies year to year based on the economy, number of students, and some other factors. Anything above that percentage is allocated by the budget passed by the legislature and signed by the Governor. Politicians and unions find it much easier to ask for more funding for schools because people are more emotionally invested in \"the children\". So they will cut the school budget before other things like prisons or public employee pensions. CA spends nearly 5 times as much per [prisoner](_URL_0_) as it does per [pupil](_URL_2_). There are more students than prisoners, but the spending per prisoner has also gone up 40% in 10 years while spending per pupil has only gone up 20%.\n\nPeople like to claim that Prop 13 is to blame, but even though Prop 13 has limited the growth of Property taxes, [CA still has the 15th highest property taxes. CA also has the highest sales and income taxes, 2nd highest gas tax, and 8th highest corporate tax](_URL_1_).",
"I live in Oregon and everyone that comes from Cali should either be in a grade above or is in all AP classes. I've found no exceptions.\n\nAnd the people I know that move to California usually post to facebook about how much more difficult the school system is there.\n\nThat just my experience, no statistics or anything behind it.",
"The State of California prints text books for use in California schools. Many of the better books are not available, since the publishers won't agree to this.\n\nWhen I was in the 8th grade, in Science class, I learned about the (sub)[luminiferous aether](_URL_1_). When I got to High School I read in (a book or magazine in) the school library that [Michaelson and Morley](_URL_0_) had done an experiment in 1887 which indicated the absence of this substance. I was appalled that it had still been in my California State Science text book in the mid 1950's.\n\nThis is an indication of the quality of texts as a result of the publishing decision made by the state.",
"It's not the entire state. There are school districts that have a lot of funding, but a huge amount of that comes from local property taxes and alumni. \nSource: I went to a really good public school in california recently. ",
"BREAKING NEWS: You'll get an excellent education if you live in a wealthy area of California. ",
"Look up how much administration has grown in the last 30 years and how much more they get paid now compared to 30 years ago. Part of the problem, right there. Money just isn't going where it needs to all too often.",
"This is just my own personal experience.\n\nCA high school graduate (and college grad in t-minus 3 days) here. I went to public schooling my entire life. Graduated HS in 2004.\n\nIn my experience, I feel like I learned just fine. In retrospect, as a greenhorn HS graduate I was indeed prepared for the rigors of community college, which in turn prepared me for the rigors of upper-division classwork at my 4-year university, which in turn prepared me for med school (hopefully lol).",
"Only thing not mentioned is massive population boom both via illegal and legal means which in turn increases class sizes. "
]
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"http://www.npr.org/2012/12/07/166745290/school-district-owes-1-billion-on-100-million-loan",
"http://en.wikipedia.org/wiki/California_Proposition_13_\\(1978\\)"
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"http://www.lao.ca.gov/laoapp/laomenus/sections/crim_justice/6_cj_inmatecost.aspx?catid=3",
"http://www.caltax.org/research/calrank.html",
"http://www.sacbee.com/2012/06/21/4579408/california-falls-to-35th-in-nation.html"
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1qn9zl | tpp | Could I get an actual ELI5 answer? I've only seen complicated answers so far. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1qn9zl/eli5_tpp/ | {
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"It's a trade partnership, which means a bunch of nations agree to standardize their tarrifs and trading laws so that its easier for businesses in one nation to sell goods to all the nations in the partnership. \n\nIt's in the news currently because the US has been negotiating to join, and one of the terms the US is looking to add to the partnership is much tighter intellectual property laws (meaning other nations would need to pass laws that are more like those in the US). (They'd feel it's worth it, because they'd have more access to US markets--which buy huge amounts of goods annually). "
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19z1ol | How important is social interaction in our everyday mental health? | askscience | http://www.reddit.com/r/askscience/comments/19z1ol/how_important_is_social_interaction_in_our/ | {
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"The way to investigate this is to read up on the effects of social isolation \n\n_URL_0_",
"In social psychology we talk about a concept called the *need to belong*. This is the desire to form and maintain close relationships with some other individuals and we call it a need because when we lack belongingness then we suffer more than just an unhappiness. People who are lonely in addition to mental health problems are often shown to have low cardiovascular output and high [TPR](_URL_1_) and have more physical health problems including higher risk of early death. \n\nHawkley, L. C., Burleson, M. H., Berntson, G. G., & Cacioppo, J. T. (2003). Loneliness in everyday life: Cardiovascular activity, psychosocial context, and health behaviors. Journal Of Personality And Social Psychology, 85(1), 105-120. doi:10.1037/0022-3514.85.1.105\n\nSo it's not *just* mental health that we're concerned with when talking about social isolation and rejection.\n\nThe effect of not belonging is linked to low self-esteem. [Williams writes](_URL_0_)...\n\n > Instead they self-ostracize, perhaps avoiding further rejection by pre-empting the possibility of acceptance. Furthermore they report a substantial rate of depression, suicidal ideation, suicide attempts, eating disorders, and short-term promiscuity. They feel little ability to change\ntheir situation, and have resigned\nthemselves to feeling unworthy of\nattention at all. Clearly, the repeated\nthemes emerging from these letters\nand interviews must be treated with ca\nution: there is no way to determine\ncause and effect. It is just as plausible that ostracism leads to depression\nas depression leads to ostracism. It is likely that both co-occur, resulting\nin a vicious cycle.\n\n... as the long term effects of ostracism and rejection.\n\nIt's called a need to belong, and not a want. This quote from Warren Jones explains why - \"In two decades of studying loneliness, I have met many people who say they have no friends. I have never met anyone who honestly said to me they didn't want to have any friends.\""
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1meckp | why do men enjoy boobs? why does it turn them on? if you think about it, it's just another part of the body. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1meckp/eli5_why_do_men_enjoy_boobs_why_does_it_turn_them/ | {
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"Because.... You know....\n\nBoobies.",
"If you are asking why men get sexually aroused by breasts, then it is a cultural thing. During parts of history women wore less revealing clothing so different parts of the body were sexualized including ankles. As clothes became more revealing the sexual zones moved. It is about seeing something that is forbidden or taboo. In places were breasts are exposed more often then they are less arousing generally. That is a large generalization, but the idea is that if you made showing the ears taboo, and had all \"good\" girls constantly wear ear muffs then a naked ear would eventually arouse the men raised in this culture."
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4wa3sb | why and how do countries deliberately violate the airspace of others'? | To avoid political discussion I won't name any specifically, but certain countries are particularly notorious for this. I'm not sure what sort of longterm political gain is made from it.
By 'how' I mean: how do the orders get to the pilots? Is it a regularly scheduled thing? Are there specific flight plans drawn up beforehand? Or is it just opportunistic? Are pilots just told to go somewhere and see if they're seen off, or do they have specific goals in mind? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4wa3sb/eli5_why_and_how_do_countries_deliberately/ | {
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"They do it to show power. Sometimes they just want to let you know that they could do something if they wanted to. It's like that kid on the playground that runs up and cock his arm like he's going to hit you and says \"sike!\" He wants to know he's stronger and see you in fear. It's not accidental or opportunistic, these pilots are given orders to fly into these areas and probably hang out for a minute before leaving. It's also used as a message to back off if one country is pissing the other off.",
"I think a lot of the time they don't wonder in to the airspace as such, it is an order to simply fly in a certain direction and see what happens.\nThis is called 'probing'. Russia does this all the time, they simply fly a bomber in any given direction (then they can deny that it was given specific orders) and then wait to see what radars they pop up on, who intercepts them etc. Its just to get an idea of air defence and response time. After a while they can build up a map of how far they can get into an airspace before being detected or intercepted. even the interceptions themselves give them an idea of radar ranged and effectiveness e.g. if we fly close to an airspace but not into it and 2 jets fly up to meet us we know they can see and track us far before we enter the airspace.\n\nI think MAYBE, in rare cases the navigation might be off from what the pilot is seeing to what the country think is its airspace but most of the time it is the 'probing' action to test defences.\n\nthis is my understanding of it at least."
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ceh7hu | why is it better to be relaxed than tense if falling from heights? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ceh7hu/eli5_why_is_it_better_to_be_relaxed_than_tense_if/ | {
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"It's like the same thing as you can break spogotter but then u be cooking teh spogotter and then u cannot break it anymoar",
"When you tense, you are making it harder for your muscles to absorb energy.\n\nSo when you fall, the energy is typically put on your bones"
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119mh7 | the economy of audio-books. why are they so expensive? | I had assumed that the process of making an audio book is a significantly smaller cost than the production of the book in the first place, and since making it an audio book expands the marketable demographic this would result in a product around the same cost as the book.
So why then are audio books so god dam expensive? I'm currently listening to an audio book that cost me £16 where as the book itself, which I also own, costs £3.99. Could someone explain the economy behind audio books.
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/119mh7/the_economy_of_audiobooks_why_are_they_so/ | {
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"The answer to \"Why does this cost so much?\" is always \"Because enough people are willing to pay that much.\"\n\nThe cost of production only puts a lower limit on the price --beyond which it would be a loss to sell the product. A lower cost of production opens up the opportunity to sell to a larger audience at a lower price, but that is not necessarily the best price to maximize your profits. If you are already reaching the the majority of your audience, lowering the price won't result in enough sales to make up the difference."
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2j48pt | when i'm angry why/how does punching walls and wanting to be violent help to relieve anger? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2j48pt/eli5_when_im_angry_whyhow_does_punching_walls_and/ | {
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"It's actually a mature defense mechanism in psychology called \"sublimation.\"\n\nYou take an unacceptable impulse, and divert it to an acceptable activity.\n\nExample:\n\nA kid is so angry at his dad he wants to punch his dad. He diverts his energy into playing sports instead.\n\n_URL_0_"
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2o0jys | the origin of miss, ms., and mrs. and how misses becomes mrs. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2o0jys/eli5_the_origin_of_miss_ms_and_mrs_and_how_misses/ | {
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"Mrs. is short for \"mistress\", which originally covered all women, but then in the 17th century, they created \"miss\" for unmarried women which also derives from the word mistress.\n\nDuring the early 1900, \"Ms\" form appeared as a catch all title for women, the equivalent to the male \"Mr\", and the term really caught on during the 70s with the feminist movement as this title can stand alone without referencing women relative to the men in their life (or lack thereof). "
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ri9r0 | How does the speed of earth traveling through space affect the passage of time? | Another post was made earlier, asking how fast an individual moves through space based on the orbit of the earth around the sun, and the sun around the galaxy. [Here](_URL_0_)
I have a couple of questions about our speed through space and the passage of time:
Since speed and time are related, does the speed of the orbit of earth influence the passage of time?
If the two orbits that give us our speed through space act in different directions, can I assume that at some points on the orbital pathways our speed is relatively faster at times than average and relatively slower at other times? If so would this mean that time passes differently during different seasons? Could this be why winter seems so dang long and the summer too short?
If the earth were completely stationary relative to all else in the universe. Would time pass differently than it currently does,.. would we perceive any difference? How would time pass on a 'still' earth compared to our 'speeding through space' earth?
edit: grammer
| askscience | http://www.reddit.com/r/askscience/comments/ri9r0/how_does_the_speed_of_earth_traveling_through/ | {
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" > Since speed and time are related, does the speed of the orbit of earth influence the passage of time?\n\nNo. Everyone (frame of reference) experiences time at the same rate (one second per second if you like).\n\n > If the two orbits that give us our speed through space act in different directions, can I assume that at some points on the orbital pathways our speed is relatively faster at times than average and relatively slower at other times? If so would this mean that time passes differently during different seasons? Could this be why winter seems so dang long and the summer too short?\n\nRelative to the what? That is the key question. Anyways no we experience time the same regardless of gravitational force or velocity and definitely not due to seasons.\n \n > If the earth were completely stationary relative to all else in the universe. Would time pass differently than it currently does,.. would we perceive any difference? How would time pass on a 'still' earth compared to our 'speeding through space' earth?\n\nThere is not such thing as stationary relative to all else in the universe. Or at the very least every point in the universe views itself as the center stationary point. Regardless no change for the stationary frame.",
"The short answer is, we're not moving fast enough to experience any serious time dilation.\n\nThe longer answer, we're moving roughly 627 km/s relative to CMBR _URL_0_. That means we are moving at roughly 0.002x the speed of light relative to CMBR. As you can see on this [chart](_URL_1_), time dilation wouldn't even be noticable to a human until you're moving around probably 0.4x the speed of light relative to the point of reference."
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bqfxy6 | Why do we think certain things/animals are ‘cute’? Is this evolutionarily beneficial or is it socially-learned? | Why do I look at cats and dogs and little baby creatures and get overwhelmed with this weird emotion where all I can do is think about how adorable they are? To me it seems useless in a survival context.
Edit: thanks for the responses everyone; I don’t have time to respond but it’s been very insightful. | askscience | https://www.reddit.com/r/askscience/comments/bqfxy6/why_do_we_think_certain_thingsanimals_are_cute_is/ | {
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"It is called „survival of the cutest“ - _URL_0_\n\nThe most extreme form is the Panda. The beneficial part is for the earthling that we think is cute, because we are more likely to support it.",
"Cuteness is linked to nurturing instincts. Part of why we find baby animals (particularly mammals) cute is their similarity to human babies. Desire to nurture human babies has obvious evolutionary advantages. This is also a likely reason why women tend to be more into cute animals than men, because they play a bigger role in nurturing children (especially in the past). However, desire to nurture babies of other species can be an evolutionary advantage in and of itself - it can lead to domestication of the animals.\n\n[Source](_URL_0_)",
"It's an application of the same instinct that causes people to think human babies are cute. There's something called the \"baby schema\", first put forward by Konrad Lorentz, which says that people find cute faces with larger eyes, bigger forheads, and retreating chins. [image link](_URL_0_). It's been shown that these traits [activate particular regions of the brain](_URL_3_) and influences cuteness perception of [both humans and animals](_URL_1_). And it gets used [for cartoon characters too](_URL_2_).\n\nAs for _why_, well those sorts of questions are always hard to answer with complete certainty, but a very plausible answer is this.\n\nHuman babies need a _lot_ of care. And, unlike most other animals, a significant amount of that care is likely to come from other individuals in the group. I mean just for starters humans are near unique in that they almost obligately need a midwife around for birth (there are exceptions both ways but they are exceptions), and the need for help with your baby continues on from there. As a result, it's very important for humans to have an instinct that pushes them to care for infants. Hence a strong \"pro infant\" cuteness instinct. The thing to remember about these kinds of instincts is that they often aren't very precise. Consider foods for comparison. We don't have an instinct to like specific foods. Instead we have an instinct to like sugars and fats and that can lead us to eat things our ancestors would never have known about. The specifics are learned. Likewise, the \"baby schema\" isn't unique to human babies, so the instinct makes people prone to thinking a whole range of things are cute. But just as with food, the details are modified by personal taste and culture.",
"Seems like you think ”evolutionary beneficial” and ”socially-learned” are the only two options, but they're not. Many human traits are more like side effects of something else, and that's likely the case here. We think certain animals are cute as a side effect of thinking human babies are cute, and thinking human babies are cute is the actual link to evolution (it clearly increases their chance of survival.)",
"Research on facial attractiveness has pointed out that the presence of childlike facial features (in women) increases (their) attractiveness. These are: \n\n & #x200B;\n\n* Large head \n* Large curved forehead \n* Facial elements (eyes, nose, mouth) located relatively low \n* Large, round eyes \n* Small, short nose \n* Round cheeks \n* Small chin \n\n[_URL_1_](_URL_0_)",
"There’s a great [National Geographic article](_URL_0_) about domestication of foxes that goes into the evolutionary benefits of cuteness, especially in relation to how humans interact with them. Floppy ears, curly tails, spotted fir. All traits that became more pronounced with domestication so humans wouldn’t feel threatened by them.",
"I work in behavior... cuteness is evolutionary and learned. But more the first... animals that are most like us genetically are thought of as most cute. But our sense of awe when we see baby animals is a reflection of our own babies and rises in us naturally when presented with a baby animal that is close to us genetically. But even baby frogs and snakes etc. can elicit a similar but not as strong response. \nIt’s just all a reflection or transference response to our own baby’s and we need more baby’s to survive.",
"It's useless *to you*, but very useful to them, because it potentially prevents you from killing them. So it's not that humans evolved to find them cute, it's that they evolved in a way we (and likely some other animals) find cute.\n\nDogs are a poor example though, due to artificial selection. A dog that's cute was made to be that way by humans, sometimes turning them into a suffering genetic dead end in the process.",
"To raise a baby is very troublesome. If we animals didn't have this trait, we would just abandon them.\n\nAbout animals, since we also like them while adults (the animals, not us), I believe we enjoy the mirroring of our own emotions.",
"Its useless to you in a survival concept. But its quite useful to the puppies and kittens. Basically, all mammal offspring have evolved to have neotenous (child-like) features - big eyes, high-pitched voices etc. And all mammal \"adults\" have evolved to react to neotenous features with adoration, empathy and protectiveness. \n\n & #x200B;\n\nThis reactivity goes across species, apparently- since humans clearly like animal babies and animal babies are godamn cute. But this is a \"by-product \" of the reactivity to neotenous features that all mammals have. \n\n\nTL: dr - The reaction to neotenous features is a part of the parent drive to help us rear our young but it causes us to feel \"cutesy \" feelings for other animal babies as well.",
"We have bred 'cute' dogs and cats over the years through artificial selection. Therefore, we find such animals to be cute and good-looking. Initially, dogs such as chihuahuas weren't even present. They are a subject of years of selective breeding. Chihuahuas would have gone extinct since they couldn't physically fend for themselves against other more dominant dogs. I would believe that we don't find other animals such as cows and goats to be as attractive since we use them for agricultural and industrial processes rather than companionship.",
"I feel there is a social element. Consider rabbits in Australia where they are generally considered an ugly pest. Or rats in most places yet they can be excellent pets.\n\nRaccoons, squirrels etc. will be cute or not based on the situation. Vermin if they break into your house, adorable if you feed them in the park.",
"It's their survival context and also ours. Dogs sought us out for food but also are protectors and can alarm humans of approaching danger because their hearing and sense of smell is so acute. A predator would be more likely to ambush a group of humans w/o a dog. It carries over into modern day life with security dogs and break ins. Intruders are more likely to target a home that is w/o a dog.",
"follow up question: i’ve never felt this emotional release/attachment to animals. i’ll be walking with a group and they all start going “awhhh” when a dog passes by and i just? don’t feel what they’re feeling? i try and play along with it the best i can as to not be an outcast but it’s WEIRD. i don’t know if this is more common than i think but most people i’ve met have been fascinated by animals and i’ve never had the same feelings. any answers/insight?",
"\"Cuteness\" is probably related to the features of human infants which encourages adults to take care of them, eg, soft rounded facial features, chubbiness, large eyes, small size, etc.\n\nAs such, they have obvious evolutionary advantage, increasing infant survival.",
"Cuteness = baby-likeness = vulnerability = protective instinct.\n\nNo better feeling than providing for a helpless living thing. Especially when we can subconsciously relate it to our own children. Mutually beneficial.",
"Certain characteristics are associated with cuteness; full round cheeks, large innocent looking eyes, much bigger head in comparison to the body, clumsiness, posture, behavior that simulates human playfulness, soft looking skin or face, among many other factors. One of the many theories about this, is that we evolved to find things \"cute\" as a way to promote nurturing and develop a willingness to care for such \"cute\" things. A cute child is more likely to be adopted and cared for than an ugly/malformed one, and evolution probably rewarded such traits. Why adopted? Ancient times were very unforgiving, and it was very likely for a child to lose one parent, or both, it was much more beneficial to the species to care for any human child, even if they were not our own, finding children to be helpless and \"cute\" was a decent driving force to ensure that. In a similar way we accidentally find this attribute in animals, since they have traits that we find \"humanly familiar\" when we look at them. \"She has puppy-dog eyes\" \"Clumsy on his feet like a newborn baby-deer!\" Is nothing but an unfortunate tendency of human psychology to invoke anthropomorphism, rather than an evolutionary advantage to domestication.",
"No substantial biology background, but I have thought about this and have a theory that seems logical. It’s a 2 part evolutionary explanation\n\nPart 1: humans find young humans cute out of a population-based protectoral instinct. Groups of people who protect the young ones in their group tend to have their genes passed on in the long run more than those that don’t. If you let the vulnerable young in your group die, your genes ultimately die too, no matter how good you may be at surviving as an individual. This is most pronounced as the genes become closer to you (your children), but still makes sense beyond that. \n\nPart 2: humans find non-human animals cute due to what I call the “decoy theory”. Basically, traits that are universally considered cute are usually traits that are linked to non-aggressiveness, and are generally speaking, unharmful. Floppy ears, uncoordinated, soft fur/skin, non-aggressive demeanor, etc. The attraction results in keeping those animals in close proximity. Keeping them in close proximity offers no notable harm to you due to the traits being unharmful, AND at the same time offers a vulnerable decoy if a threatening predator enters the picture. This explanation also explains why below a certain size (bugs, etc) cuteness isn’t really prevalent, AND why women generally experience a more pronounced cutenesses sensation; they tend to benefit more from the decoy.",
"Neotony and kinderschema\n\n\n\"Adding cute human traits to animal characters in order to make them more likeable is not simply anthropomorphism, though. In real life, the human affinity for kinderschema is so pronounced that it frequently spills over to members of other species. Because they too display many of the traits as human children (some even have the added cute trait of being fuzzy!), animals can also appear achingly cute to us too.\"\n\n_URL_0_",
"Apparently we found animals who most resemble human babies the cutest...it's all based on the size of the eyes and forehead etc. I remember reading about it once. It's the reason why women especially love small dogs with big eyes.",
"Not at all useless. It helps survival. If we didn't think little things were cute, we probably wouldn't take as good of care of them. We derive joy/pleasure/happiness from their innocence and beauty and want to keep them alive. It's not only from the way that they \"look\" but the way that they are: sweet, nice, playful, happy, loving.",
"I'm not trying to directly answer the question, but i have an interesting, related insight. \n\nIn an environmental comms course I learned about \"charismatic megafauna\" which is a term used to group animals like polar bears, seals, pandas, etc. Basically the trend is these cute, charming types of animals are leveraged in campaigns by NGOs like PETA etc because of their widespread appeal. There are no posters urging us to *save the plankton*, despite that being of arguably greater importance. Bees have broken into the threshold lately, which I enjoy.",
"For our domesticated cats and dogs there has definitely been evolutionary drivers to have young which appeal to our instincts. Kittens look, behaviour and the way they sound (human baby cries) in particular. \n\nProbably a bit the other way as well. Humans who liked having cats and dogs around are less likely die of the plague or be eaten by bears. So more likely to pass on those liking pets traits to their young.",
"Cuteness has been identified as a unique set of characteristics that baby humans and other animals have and that things may be designed to have, as well. These characteristics Include oversized eyes, shortened limbs and chubby curves. \nAnother word for this is “Neotony”. \nThis is evolutionarily beneficial because we are not only hardwired to want to care for cute creatures (and this, not abandon our young), but also evolutionists have theorized that Neanderthals refrained from killing us because we looked like their children. Humans had cute features!",
"When an obnoxious, loud, inexpensive alarm clock wakes you out of a sound sleep, you'll throw it across the room to quiet it. Cuteness evolved to prevent us from doing the same with babies when they scream and cry."
]
} | [] | [] | [
[
"https://www.sciencedaily.com/releases/2010/01/100120093525.htm"
],
[
"https://pdfs.semanticscholar.org/a832/f3be4a565534808568a4bc808d618600c4e0.pdf"
],
[
"https://en.wikipedia.org/wiki/Cuteness#/media/File:Animal_human_growth_skull_neoteny_cuteness_maturation.png",
"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4019884/",
"https://web.archive.org/web/20100828081700/http://todd.jackman.villanova.edu/HumanEvol/HomageToMickey.pdf",
"https://www.pnas.org/content/pnas/106/22/9115.full.pdf"
],
[],
[
"https://www.uni-regensburg.de/Fakultaeten/phil_Fak_II/Psychologie/Psy_II/beautycheck/english/kindchenschema/kindchenschema.htm",
"https://www.uni-regensburg.de/Fakultaeten/phil\\_Fak\\_II/Psychologie/Psy\\_II/beautycheck/english/kindchenschema/kindchenschema.htm"
],
[
"https://www.nationalgeographic.com/magazine/2011/03/animal-domestication/"
],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
[],
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"https://www.stuffyoushouldknow.com/blogs/babies-cute-explained.htm"
],
[],
[],
[],
[],
[],
[]
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|
30si2z | when the u.s. started adding fluoride to our tap water, how were other animals affected? | Did fish have much nicer teeth? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/30si2z/eli5_when_the_us_started_adding_fluoride_to_our/ | {
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"Fish do not have teeth. Adding fluoride to potable water supplies without fluoride naturally only seems to affect our teeth. Tap water gets discharged to sanitary sewer systems which discharge treated water into much larger bodies of water. The fluoride is diluted. It flows to the sea. It does not evaporate into the air the way water does."
]
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[]
] |
|
g1dq06 | why is paddle shifting still considered automatic transmission? | Why is a semi-automatic, paddle shift still not the same as manual gear switching and is not as good as a manual for drifting, etc. Thanks! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/g1dq06/eli5_why_is_paddle_shifting_still_considered/ | {
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"A quick answer: Clutch\n\nA manual gear box has a clutch that can be disengaged at any point in time removing power from the power train. \nThe clutch can also be partially engaged via a pedal much the same as the gas pedal to give variable amount of power, known sometimes as “bite”. \n\nThe clutch is essentially to large plates typically the size of dinner plates. They exist between the engine and drive train. The clutch when disengages allows the engine to run whilst disengagement of the drive train so a gear change can be made. \n\nClutch plates are typically very durable and are designed to grip.\n\n[This is a great demo](_URL_0_)",
"You can't \"dump the clutch\" with a paddle gearbox. This is where you redline the engine with the clutch disengaged and then very rapidly lift the clutch pedal - the massive surge of power to the wheels when you do this allows you to break traction and spin the wheels.",
"Paddle shifters don't have a mechanical link between the controls (the paddles) and the transmission. With a manual transmission, you actually move gears around when you move the shifting lever."
]
} | [] | [] | [
[
"https://auto.howstuffworks.com/clutch.htm"
],
[],
[]
] |
|
7aq7b5 | Why do our teeth get so easily rotten? | why are we required to brush twice a day etc. to take care of our oral health? | askscience | https://www.reddit.com/r/askscience/comments/7aq7b5/why_do_our_teeth_get_so_easily_rotten/ | {
"a_id": [
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"text": [
"They don't rot easily, in fact cleaning teeth only exists since the 20th century. There's a nice story of the US-Allies introducing toothpaste to the people of Upper Austria after they fought back the german troops: They handed it to kids who thought it would be some kind of sweets and ate all of it."
]
} | [] | [] | [
[]
] |
|
4awall | can a tech or software company just move out of the us so they don't have to deal with government demanded backdoors? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4awall/eli5_can_a_tech_or_software_company_just_move_out/ | {
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"text": [
"Yes, yes they can. But that would be a very very very expensive thing to do. ",
"Yes. Assuming the country they move to doesn't demand backdoors either. Also, they would have to move *all* their operations overseas.",
"A small one might be able to do so. A larger one would have considerable difficulty because their employees probably wouldn't want to leave the country and they'd have considerable recruitment difficulties going forward."
]
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[],
[],
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||
qzjz5 | How does sound behave in a Black Hole? | askscience | http://www.reddit.com/r/askscience/comments/qzjz5/how_does_sound_behave_in_a_black_hole/ | {
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"We have theories about black holes, but I don't think they involve oscillations of the kind we would call \"sound\". Even if we did, we would have no way to verify the hypothesis.",
"Here is an interesting article about the lowest musical note ever recorded and it came from a black hole. A within a black hole, there is no way to tell if there is sounds, but outside of a black hole (beyond the event horizon) escaping particles can make sound.\n\n_URL_0_ "
]
} | [] | [] | [
[],
[
"http://www.cbc.ca/news/story/2003/09/09/black_hole030909.html"
]
] |
||
6oqnrr | why can phone companies claim they are better than others by using the company name, but other items have to say "competition"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6oqnrr/eli5_why_can_phone_companies_claim_they_are/ | {
"a_id": [
"dkjf4tv"
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"score": [
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"text": [
"They have to substantiate their claims. They need to cite a study that shows their claim is true in order to say it."
]
} | [] | [] | [
[]
] |
||
53lhbm | What is the oldest organization that is still active? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/53lhbm/what_is_the_oldest_organization_that_is_still/ | {
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"text": [
"I dont know the answer, but I do know the Eastern Orthodox Church predates the catholic church by a few hundred years"
]
} | [] | [] | [
[]
] |
||
3ldxl1 | if blackjack is a game of 'skill', how is it not allowed in states that don't have gambling? | I understand games of chance (lottery, roulette, etc) being illegal because it's truly gambling. But if blackjack (and poker) are games of skill, how are they not allowed in those states? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ldxl1/eli5if_blackjack_is_a_game_of_skill_how_is_it_not/ | {
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"text": [
"Blackjack/Poker can be a game of skill AND gambling. Gambling is just the wagering of money on an event with an uncertain outcome. Think of it as still being a game of chance (like roulette, craps, etc.) with a meta-game of skillfulness and card counting.",
"they are still games of chance- you can't control what card is drawn at all, and sometimes you get fucked over by random chance and there is nothing you can do about it. likewise, it doesn't take a world champion poker player to pull a royal flush. however, there is a strategy aspect on top of that; unlike, say, slots.",
"If blackjack is a game of skill (rather than just memorisation of tables to ensure losing at the slowest rate) then the casino consider you to be cheating and will kick you out. The skill would typically entail identifying randomisation flaws such as insufficient decks in the shoe, and then counting cards. Poker is very different, it's player v player with the casino merely taking a vig, a game of skill by design rather than by accident. It appears alongside blackjack only due to tradition. The luck v skill argument is a red herring in either case, in 100% of real world instances the games are legal iff the right people are getting their cut.",
"Its not a game of skill, or at least it isn't purely one.\n\nNo matter how skilled you are, you cant make an ace appear in your hand (barring cheating). The skill is in calculating odds, reading the other players and decision making, so essentially how you react to the cards and others."
]
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|
1ri13j | What role, if any, did the Irish play in the American Revolution? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1ri13j/what_role_if_any_did_the_irish_play_in_the/ | {
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"One roll played by many Irish was one of leaving. My only source on this is John Rawlston Saul's book \"A Fair Country\" talking about the mixed nature of Canadian identity. In this book he states that the United Empire Loyalists, the groups of Americans that fled the United States for Canada following the loss of the revolutionary war, was made up of several groups. The largest group was German religious minorities, fairly sceptical of religious freedom in the states' new melting pot, and the second largest group was Irish and Scottish Catholics, fleeing again religious persecution (remember one of the intolerables was that Canadian Catholics had the vote, there was a strong religious undertone to this).",
"Well;\n\n''Irish immigrants of this period participated in significant numbers in the American Revolution, leading one British major general to testify at the House of Commons that \"half the rebel Continental Army were from Ireland.\"[16] Irish Americans signed the foundational documents of the United States—the Declaration of Independence and the Constitution—and, beginning with Andrew Jackson, served as President.''\n\n_URL_1_\n\nThe cited source is:\n\nJump up ^ Philip H. Bagenal, The American Irish and their Influence on Irish Politics, London, 1882, pp 12–13.\n\nAlso;\n\n_URL_0_\n\n''A few following documented facts will reveal some accurate history of Irish participation in the American Revolution.\n\nBattle of Lexington (April 19, 1775), 174 Irish were present.\n\nBattle of Bunker Hill (June 17, 1775), 698 Irish were present.\n\nA prominent American, Joseph Galloway, also an English Tory, on Oct. 27, 1779, told the English House of Commons that one-half of Washington's Continental Army was Irish.\n\nOn April 2, 1784, Luke Gardiner, afterward Lord Mountjoy, told the English Parliament, \"America was lost by Irish emigrants ... I am assured from the best authority, the major part of the American Army was composed of Irish and that the Irish language was as commonly spoken in the American ranks as English, I am also informed it was their valor that determined the contest ...\"''\n\nHowever, I'm not too sure about the second claim, seeing as it's a newspaper."
]
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[],
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"http://www.dailyherald.com/article/20110622/discuss/706229716/",
"http://en.wikipedia.org/wiki/Irish_American#17th_to_mid-19th_century"
]
] |
||
abhjti | why do unicode emoji depend on the platform instead of the font which is used? | Why does their look depend on the platform used (as depicted [here](_URL_0_)) instead of the font? For example, if a certain font is used on character "A", its look does not depend on the platform on which you see it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/abhjti/eli5_why_do_unicode_emoji_depend_on_the_platform/ | {
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"As part of the Unicode set, emojis can be made part of a font. \n\nA complete font (with emojis and stuff) can be huge, so most systems probably store only one complete font and allow you to change only part of it.",
"To save time and space, operating systems will store a shared library of fonts. Emojis are just pictorial representations of the Unicode integer value. To store different versions of each emoji would eat up a lot more space in storage and memory. \n\nAn example of something different is Facebook. They have their own set of emojis and they store that in the app and online. They still don’t use multiple sets of emojis but they do have a set separate from the main set used by the operating system.",
"You are correct in assuming it depends on the font, and not really the platform.\n\nThere are two reasons why platforms have a typical style.\n\nFirst, there are tons of emoji and/or Unicode characters, and usually the platform provides one complete font (with all the characters) and lots of partial fonts (most about Latin characters, some about Asian ones).\n\nSecond, programs decide to use either the selected font or their special font, then fall back on the system font for missing characters.\n\nFirefox on Windows have two styles of emoji, some are handled by Firefox emoji font, the others are handled by Windows, and some are not handled at all because Windows default font is not even complete.\n\nWhatsApp on Android also have its own emoji font (to be more uniform across all devices). Therefore the emoji on there are not the Android emojis."
]
} | [] | [
"http://unicode.org/emoji/charts/full-emoji-list.html"
] | [
[],
[],
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|
8jlyrh | Were soldiers in the Conquistadors' armies well paid? | It seems like it was a very dangerous job. Were they promised great riches? Did they get what they were promised? Do we have any accounts of the lives of rank-and-file soldiers after their conquering days? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8jlyrh/were_soldiers_in_the_conquistadors_armies_well/ | {
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"text": [
"Conquistadors were not really soldiers in the modern sense. They were not paid a salary, so their recompense was typically in looted goods, preferably gold and silver. However, their motivation to go and become a conquistador was to win an encomienda, which is a quasi-feudal institution where a population of 'indians' were given as a labour force to individual Spaniards. Of course, getting an encomienda was closely related to wining honours from the Spanish Crown, including coats-of-arms and other forms of status recognition. Thus, the ultimate goal of each Conquistador was to achieve social status. When a Conquistador had achieved this, they would settle on an estate, or more frequently, in a 'newly founded' Spanish city in the New World and live as a noble citizen.\n\nAt least, this was the 'ideal.' Many conquistadors did not receive much wealth from their conquests, as many native societies were not as rich in gold and silver as many of the Spaniards had assumed. Furthermore, the the rights and labour grants they thought they were entitled did not always materialise, either because the labour was not available, or because the Crown did not want to give too much political and social power to what was essentially a band of raiders. So many conquistadors kept on going, heading to the next raid in the hope that it would prove more productive than the last."
]
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[]
] |
|
3k9do9 | please help me understand the difference between being sad and having depression. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3k9do9/eli5_please_help_me_understand_the_difference/ | {
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"Being sad is usually a passing feeling and theres a reason behind it. Like, i was on my way to work and spilt my coffee down myself, broke up with my boyfriend, accidentally killed my dog and its Monday. That would make someone sad but they would get over it. \n Depression is feeling shit nearly all the time. Its feeling unmotivated, useless and lazy. You don't even want to do the things you love anymore. Its not just feeling sad, its feeling nothing. Its also due to a chemical imbalance in the brain, not just because something shitty happened like it is when you're sad. (This is kind of just my opinion, please don't attack me :P) ",
"There's being sad, and being incapable of being happy. Depression is most usually not overwhelming sadness, as much as it is an empty feeling, just going through the motions of life, uncertain of what it is you are doing. You aren't always sad, but you're never happy. ",
"Sadness is a state where you get over it. For instance, I get sad when I can't hang out with my friends, but I know we can hang out next week. It is temporary.\n\nDepression is a state where you can't get over your sadness. For instance, if your children die in an accident, you know they won't be back - you can't \"replace\" them. That might cause someone to be unable to be happy again.",
"Allie Brosh of Hyperbole and a Half does the best job of explaining what it feels like to have depression in these two comics (if you only read one, read part 2):\n\n_URL_0_\n\n_URL_1_",
"The difference between my feeling depressed vs. sad/blue is that a depressive episode (I have experience, so I'm not guessing) interferes pretty significantly with my every day life. Along with the significant, all-encompassing melancholy, and possible suicidal ideation, comes lack of focus, exhaustion, intense apathy and a sort of paralysis...All that combined make getting through a regular day a real challenge. The duration of a depressive episode is also usually longer than feeling sad about something.\n\nWhen I feel sad/blue, the depth of the feeling is less than depression, and it might weigh on my mind but it does not interfere with my every day life."
]
} | [] | [] | [
[],
[],
[],
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"http://hyperboleandahalf.blogspot.com/2011/10/adventures-in-depression.html?m=1",
"http://hyperboleandahalf.blogspot.com/2013/05/depression-part-two.html?m=1"
],
[]
] |
||
e57v7o | Do louder songs have a bigger file size? | Lets imagine a computer uses 10 units to save an audio file. Would a version of a song less loud take the same amout of units because of the units that it takes to describe that the song is not louder?
I hope this makes sense | askscience | https://www.reddit.com/r/askscience/comments/e57v7o/do_louder_songs_have_a_bigger_file_size/ | {
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"text": [
"File size is only determined by the amount of stuff, not what that stuff is. To a computer, 5 minutes of extremely loud music is stored the same as 5 minutes of near silence. Once the space is dedicated to that file, it'll always take up the same amount of space",
"An integer takes the same space no matter whether you put 0, 3, or 2 billion in it.\n\nHaving said that, with lossy compression algorithms and their 'quality'/'variable bitrate' modes, music with a lot of frequency components (eg distortion) would take more space than very simple music with only a couple of frequencies per unit time.\n\nFurthermore, songs that have been compressed (audio filter) gain a bunch of distortion from the nonlinearities introduced, and thus will both sound louder and take more space when saved with a VBR format.\n\nIn short, the volume *by itself* doesn't alter the filesize, however some types of audio modulation (which tend to be experienced as louder by humans) *can* increase the file size when using specific codecs."
]
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[],
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] |
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46ixsh | How financially privileged was slave ownership in America? Could a "middle class" American own slaves, or was this only reserved for the very elite? Do we have knowledge of what percentage of Americans owned one or more slaves? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/46ixsh/how_financially_privileged_was_slave_ownership_in/ | {
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"The reason why we tend to think of slavery as being synonymous with large plantations, and why these portrayals are the norm in popular media, is because this was essentially the normal experience from the perspective of the enslaved. The vast majority of *slave owners* though did not have a substantial number of slaves and were not operating plantations. In 1860, we estimate that about half of all slave owners in the Old South would have owned only a single slave; a similar percentage would have owned fewer than half a dozen across the entire South. Missouri in particular stands out for the prevalence of small-scale slave ownership: about nine in every ten slave owners in that state had fewer than ten slaves to their name, and plantation farming was comparatively rare, the norm instead being a culture of slave ownership where master and slave worked alongside each other on small estates in a much more intimate environment than the plantation economy provided for. In general, the 1860 census of slaves and owners seems to suggest the vast majority of US slave owners owned fewer than 10.\n\nAll in all, the figures from the 1860 census indicated that there were 393,975 slave owners in the United States owning 3,950,528 slaves - in other words, the average slave owner only had about 10 slaves, which is half the number normally required to denote the distinction between regular farming and plantation farming. The actual figure, it should be noted, might be slightly higher or lower because the Census is only a snapshot of the day it was taken (and so sometimes slaves might be on the wrong estate, working for someone who didn't own them, etc., and this isn't always identified). That average is of course heavily skewed by those minority of owners who did have many slaves working on large plantations and who formed the centre of the Southern elite. All in all, that actually means only about 5% of the Southern population owned slaves. It is crucial to understand though that there is a distinction to be made between someone who *owns* a slave and someone who *has access to slave labour*.\n\nGenerally speaking, slaves would be owned by a single person - usually the white male head of the household. The owner's spouse and children (who stood to inherit ownership, and who cannot generally, of course, legally own a slave before the age of maturity) are not included in that figure, even though they would have obviously benefited from slave ownership. Nor are other family members, friends and associated who benefited from slave ownership. Likewise, practices like hiring out surplus slave labour or having slaves perform services for the wider community (like refuse collection in urban environments, or working in commercial services for white people) mean that many, many more people had access to and benefited from slave labour even if they were not slave owners themselves. The general consensus is usually that around one-third of all white southerners had a *direct* interest in the continuation of the slave system, though there is debate as to how widespread the wider benefit of that ownership is precisely, and of course there are variations between region to region and county to county. In South Carolina for example, probably about one-in-ten people actually *owned* slaves, and five times that number belonged to a family that did, in 1860.\n\nThe affordability of a slave would vary enormously depending on circumstance - the state, the particular market, the perceived condition or value of the slave, the terms of sale the owner or trader was willing to accept (some sellers would happily accept certain agricultural goods in lieu of cash) and so on. But generally speaking, you would be looking at an investment of *about* $800 for a slave in the late antebellum period, assuming you wanted a 'decent' worker. Consider this this extract from an abolitionist's account of a slave auction in Montgomery, Alabama held on March 24th, 1854, listing the various prices for a slave typical of this period:\n\n > Woman and small child, $1050; man aged 19, $950; man and wife aged 18 and 17, $2000; boy aged 14, $640; girl aged 10, $525: man aged 24, $860; boy aged 11, white, $585; boy aged 11, white, $625; woman aged 25, $900; man and little boy, aged 50, $1020; woman age 46, $395; man, with the gravel , aged 19, $700; man, perfect aged 40, $1600; woman 40, girl 8, $600; man aged 27, $1410; boy aged 12, $725; girl aged 4, $300; girl good looking, aged 14, $855; girl, a little blacker, aged 15, $845. [from The Liberator, \"From the Car Leader\", April 21, 1854]\n\nYou will notice that the \"perfect aged\" man (i.e., a healthy, male worker) aged 40 goes for $1,600; a young couple for $2,000. But you could also have acquired a young boy for much less, or opted for a woman and child for half the price of the young couple. The average price across the whole group of 23 slaves is $721, though this is of course an *auction*, and so another auction with a different set of slaves or a different set of buyers could produce an average price above or below that. From the perspective of someone looking to set out as a slave owner for the first time, the most logical investment would arguably be the young man and wife; their extremely high price reflects in part their reproductive value as well as their labour potential, in the sense that they would have a very good chance of having one or more children who would in turn become your slaves as well, both adding to your labour force *and* to your wealth (because you now have two more slaves you can in turn sell yourself).\n\nFor reference, $800 in 1860 would be roughly $23,500 today in terms of what that money could *buy you* if you went shopping with it. But in 1860, the wider economy was not nearly as affluent or prosperous as the modern-day economy is; put simply, there was less money to go around. As a share of the total value of the economy measured by GDP (how much money the national economy is worth based on everything it produces in one year), $800 is about the same share of national wealth in 1860 as $3.2million USD is today. So in other words, $800 in 1860 has the *purchasing power* of $23,500 today, but it is about as *wealthy* as having $3.2million USD today. Whichever way you look at it, it puts into perspective just quite how much wealth was tied up in slaves and how much of an investment even a single slave could be: if you think of stocks and shares and property in more recent times, how many people have the wealth of equal to just *one* slave tied up in assets today?\n\nWhen you think of it in those terms, it is not surprising that only a minority of white southerners actually were directly involved in slave ownership; a 'decent' slave costs a lot of money - though as we've seen, you could certainly opt for cheaper investments, or be smarter in how you invest your money to make a long-term profit. And of course, sometimes slaves could be purchased on credit, though this phenomenon has perhaps been overstated by some historians. So the answer to your question really depends on what you mean by a \"middle class\" American. Many of those small slave holders presumably made a significant and costly investment in just one or two slaves in the hope that the long-term benefit from having extra, low-cost workers would pay off - and also for the social capital that came with joining the slave owning class in even a small way. But certainly most of these small slave holders would not have been living the 'gentlemanly', luxurious lives of the plantation elite either; they were arguably the middle class of the rural South, but depending on their particular circumstances and what we prioritise in class formation, we might think of them as being more or less well-off than that language implies when we talk about the modern world. Certainly, few of those slave owners were truly part of the elite that dominated Southern society at this time - and when the Confederacy was framing its conscription laws during the Civil War, small-scale slaveholders were not exempted whilst the plantation owners who dominated the Confederate polity explicitly were.\n\nSo this is one of the curiosities of slave-owning: even owning one slave implies a not insignificant measure of wealth, either on credit or by cash, and as an investment by the late antebellum period purchasing a slave is perhaps somewhat comparable to paying a substantial deposit on a house today in terms of the amount of capital one needs to have. Yet at the same time, despite this being a period in which wealth in general is scarcer and less broadly distributed, a sizeable minority of southern families were able to make that investment. The significant quantities of wealth tied up in slaves though would prove to be problematic in the long run - abolition essentially destroyed nearly all of that wealth over night by making it impossible to either claim compensation or to sell your formerly Human property for any kind of return. If you were a slave owner who had made that $800 investment in 1860 on a single slave, by 1866 your investment was gone forever. A mind-boggling amount of wealth disappeared from Southern society when slavery was abolished (Britain, for its part, abolished slavery with compensation in part to try and prevent this from happening in the Caribbean - with very mixed 'success').\n\nThis is also, incidentally, part of the reason why the Upper South was also so affluent even though it did not harvest intensely profitable crops like cotton. The Upper South had an abundance of slaves and a paranoid fear about what that meant for security and stability (especially Virginia, which is perhaps uniquely terrified of slave uprisings throughout the history of slavery); it was able to sell those surplus slaves onto the labour-hungry plantations of the Lower South to supplement its own more limited, though by no means meagre, agricultural profits."
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3aj0qi | how does war 'work'? | This is something I've been confused about for a long time, and was hoping for a little enlightenment. Is it like a game? If so, what are the rules? How do nations or groups 'declare' they're at war with each other? Why resort to violence in this day and age - why not a debate? How is it decided who 'wins' the war - is it by the number of people die/when the leader dies?
Lots of questions, thanks for any replies! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3aj0qi/eli5_how_does_war_work/ | {
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"War is not a game.\n\nHowever, in a 'just war' (declared so by the UN) there are rules. These generally follow that of the Geneva Convention (Be nice to Prisoners-Of-War, don't kill innocent civilians etc)\n\nNations generally declare war through the UN (United Nations)\n\nSometimes debates just don't work, sometimes one side refuses to listen to the other and war is the only option. War also happens when one country is persecuting its own people or when another country is doing something bad, in this event a debate wouldn't be the best idea as this behaviour needs to be stopped immediately.\n\nWars are won through a variety of different means. Sometimes nations give up due to the fact that they've lost too many people (public pressure) and sometimes they give up due to the fact they they are surrounded by the opposing nation, and that carrying on the war would reduce the losing nation to dust (and they don't want this).\n\nSometimes wars are stopped when the leaders die, this is another method of stopping a war.\n\nEverything I've explained is *incredibly* simplified, if you want more detail/anything explained then give me a shout :)"
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clf6dc | how do octopi camouflage? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/clf6dc/eli5_how_do_octopi_camouflage/ | {
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"Cephalopods have a bunch of specilized cells carrying different pigments and such.\n\nThey can constrict or contract these cells to change the color of their skin on the fly.\n\nThey are also able to change their texture as well. Cephalopods without shells or bones I.e. squids and octopuses are able to squeeze through any size hole as long as it's larger than their beak. They're basically highly intelligent goo. And as such their skin basically does whatever they want.\n\nCephalopods are fascinating creatures that gave up their ability to \"rapidly\" evolve in exchange for an ability to essentially rewrite their RNA on the fly in order to better suit their environments. From my understanding they are the only animal with this ability."
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agl42n | what's the difference between reptiles and mammals that allows one to be warm blooded while the other can't create its own heat? | As far as I know all the major organs are roughly the same between cold and warm blooded creatures - lungs, hearts, brains. Do mammals have an extra organ that lets us produce our own heat? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/agl42n/eli5_whats_the_difference_between_reptiles_and/ | {
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"Part of it is mammalian cells aren't particularly good at holding substances within themselves, so they pump into their cells more. The pumping generates heat as waste, this heat keeps them warm.\n\n[_URL_0_](_URL_0_)\n\n\\*citation added in edit\\*",
"some cold blooded animals do generate their own heat by muscle action, but they do not maintain a specific, stable body temperature. At rest, cold blooded animals slow down heartrate, respiration, digestion, etc\n\nActive predatory fish like tuna have powerful muscles that make a lot of heat, and help the fish to move fast and swim hard to catch it's prey.\n\nA snake at rest will stay cool, warming up in the sun when it wants to, but they can turn up the temperature metabolically when they are digesting a big meal.\n\nMammals basically \"keep the heat on\" all the time with a high metabolic rate *even at rest*, so just the action of digesting, breathing, growing, etc uses energy and produces heat as a byproduct of that energy use. ",
"It is our cells that creates the heat when it produces energy for the body to use. In a mammal the cells are set, like a thermostat, to always aim for a certain temperature regardless of outside temperature and if the energy is needed. In a reptile the cells don't have this setting and instead uses the outside temperature to regulate how much energy is used.\n\nIt is a trade off between not wasting energy and being able to function in different climates.",
"Different hearts in Reptiles.\n\nAll lizards, snakes and amphisbaenians (worm lizards) and turtles have a three-chambered heart consisting of two atria, one variably partitioned ventricle, and two aortas that lead to the circulation.\n\nSome species (like pythons and monitor lizards) have three-chambered hearts that become functionally four-chambered hearts during contraction of the heart\n\n_URL_0_\n\n_URL_1_\n\nCrocodilians have a four-chambered heart like a bird, but still has some of the features of a lizard heart"
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9uj0uw | how does the automatic wiper blades works? | Some cars have a system in wich the wiper washer auto activates when is raining, and adjust itself to how hard it's raining. At the start I figured it can work with some kind of system that measure the water that falls down the windshield, but when you throw water into the windshield it seems to start working before the water reach the bottom of the windshield.
I know it seem a silly question, but have been bugging me for some time so... is there any car engineer in the room? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9uj0uw/eli5_how_does_the_automatic_wiper_blades_works/ | {
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"Im no expert but from what I know if existing sensor technology I can guess:\n\nProbably measuring the capacitance of some surface layer, when it changes in a recognizable way, like when a conductive liquid (i.e. water) is on it it triggers a response that scales with the change in capacitance....\n\nIt's how our touch screens work on our phones and tablets, so it's probably similar - likely with less granularity than a phone though. ",
"Most have this clever system that relies on how light bends when it goes through stuff like glass & water. They project some infrared light through the glass at a 45 degree angle. if the glass is dry most of it gets reflected back to a sensor. But if there are rain drops on the glass some of it will be scattered. The more rain drops there are the less is light reflected back. \nThe system will turn on the wipers if the amount of reflected light reaches a low enough level. \nIt also keeps sensing between wipes & if it detects too many rain drops building up between sweeps it will increase the frequency. "
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2192la | why can't all the animals/fish that we are eating to extinction be farmed instead? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2192la/eli5_why_cant_all_the_animalsfish_that_we_are/ | {
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"They can.\n\nTo begin with we are not hunting any animals to extinction, and take great steps to prevent extinction when we can.\n\nAs to fish, we are not really fishing anything into extinction but we are overfishing. There has been an effort to begin farming fish, known as aquaculture, but it has not become as widespread as one might hope. "
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53vj7o | what distinguishes vowels from consonants? | Some languages have less than 5 vowels. What distinguishes them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/53vj7o/eli5_what_distinguishes_vowels_from_consonants/ | {
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"Consonants involve a constriction of airflow through the vocal tract. On the other hand, air flows freely through the tract when pronouncing a vowel."
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3xwxt4 | Writing with style; or, how do you write history that people want to read? | This is a question for other academic historians: what do you do to improve your writing style?
I'm very good at writing dry academic prose, but I always prefer reading work by historians who use their language well. People like Peter Brown whose metaphors communicate meanings deeper than the words on the page, and draw the reader in by gripping her imagination.
But I spend most of my time reading precisely the wrong sorts of things to improve my own writing - lately, it's been nothing but osteology reports. Nothing strips magic from your prose like reading a bunch of scientific tables held together by clinical description. I feel like I'm training my brain to write the kind of book I wouldn't enjoy reading.
What do you do, fellow historians, to improve your style?
Do you have favorite authors you turn to for writing inspiration? Historians who tell good stories, or pull deep meaning from deceptively simple prose? Great literature (or trashy fiction) whose language you try to copy? Poetry? Art?
Do you have other tricks for nuturing a writing style that adds richness, color, and texture to your academic prose?
| AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3xwxt4/writing_with_style_or_how_do_you_write_history/ | {
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"Anthony Beevor sprinkles his books with amazing anecdotes that really drive it home when it comes to the chaos and horror of war. Read any of his books and you will see what I mean.",
"This is a topic that is near and dear to me, because I love great literature as well as great history. Unfortunately, in my opinion, only two people managed to write great works of history which were also great works of literature: Edward Gibbon and Winston Churchill. In the modern era I agree with you about Peter Brown: he is a superb writer as well as a superb historian.\n\nI have two different methods I use in an attempt to improve my writing. First, I also write fiction. In fact, I try to alternate between fiction and nonfiction as I publish. I don’t think it is necessary to write fiction for publication, though: they could just be short stories for your own enjoyment.\n\nThe rules of fiction are different and allow more flexibility in the text. When you are used to it you can employ some of those same methods in nonfiction text. Even the structure of a history book can be influenced by the traditional plotting you see in novels, and your description of historical individuals can be improved by using some of the characterisation methods of novels.\n\nMy second method is that my main editor is actually a fiction editor. He has had a long career in fiction and really knows his stuff. His help has greatly improved my nonfiction prose as well as the structure of my nonfiction books. Under my main editor we use a nonfiction subeditor who is familiar with my field and is able to spot factual errors or problems with my arguments – the main thing historians seem to worry about in regards to which editors they choose.\n",
"I write like I'm writing a speech: I imagine myself giving it as a lecture. That's why my AH answers are always filled with crazy amounts of parentheses and especially italics--it's me trying to capture the rhythms of how I would talk it.\n\nIn general, I just try to write really clearly and use good topic sentences for each paragraph. Seems to go over pretty well. I mostly get criticized for overusing italics. :)\n\nMy advisor, meanwhile, tends to adopt the writing style of whatever *primary* source he's working with at a given time, *in its original language*. This is especially hilarious when he's working with something in classical or humanist Latin. The ablative absolutes, they abound.",
"The most entertaining writers tend to write for humerus but intelligent publications like the New Yorker, The Times, and so forth, so I read those and try to draw some inspiration from it. I have noticed that many historians read the New York Times in particular. \n\nMy normal writing style is rather plain and straightforward. Many people say they like my writing because I am able to explain complex subjects simply. I think that is the greatest compliment for an academic: Understanding. If I had to name the author I wish I wrote like the most, it would be Ernest Hemingway. Despite being a giant of literature, nearly every one of his published sentences was a Simple Sentence, and he almost always avoided commas. ",
"I don't know if this is the same, but as a fan and consumer, I think Erik Larson is able to make some really interesting page turners. I haven't looked into on how the majority of his profession thinks of him, but I read The Devil In The White City in 3 days and remember everything about it, bought a book on the history of the world's fair in San Francisco, and sub'd to this sub reddit because it reignited my love of history.",
"T.S. Eliot for phrase, Marc Bloch for punch. If you want an audience interested in sources, write in the style of your sources—Bede (or Felix) for form. And if you choose to pursue an ethos of history (historia—Gk. \"inquiry\"), pose questions, not answers. A riddle asks more thought than a reason.",
"The first step is to correctly identify the audience you are writing for. You are probably not writing for a \"general audience\" — there is no such thing, really (there are a multitude of different, fractured audiences), and you probably don't want to write for that broad a public anyway (writing for people without at least a high school education is _very_ hard, as is, if you have a PhD, writing for people without a college education, because grad school writing is generally about writing for people with PhDs). \n\nMy term for the audience I usually target is the \"NPR audience,\" which means \"educated (largely American, middle class) professionals.\" It includes the readers of the New York Times, Atlantic, New Yorker, etc. It also includes many academics, which is a bonus, but it is not exclusive to academics. (Consider the difference between this audience and the audience that reads the New York Review of Books — the latter is generally much older and much more highly educated, and as a result a much smaller audience.) \n\nHaving done that, you have many models for writing. The key thing is that it is not about \"dumbing down\" — it is about being clear, avoiding discipline-specific jargon (unless you are willing to devote space to explaining it), and keeping things relatively short (if it is an article, it _needs_ to be under 2,000 words unless you are really doing something quite long-form and special — even then, you need to be _really_ good at your craft if you are going to be holding someone's attention that long, so you shouldn't _start_ by doing that). Books of course are longer but you really need to keep the chapters shorter than is standard in academic monographs. \n\nBecause space is so limited you need to make real decisions about whether you want to talk about other scholarship (in general you do less of this unless you really think it is important or that the audience in question will know or care about your \"intervention\"/\"engagement\" with exclusively academic concerns), whether you want to bother explaining jargon (or just write so you don't need it), or how many little asides and witty points you want to make. I have found my writing works best when I figure out, from the beginning, exactly what one or two points I want the reader to come away with, and tailor the entire piece around that point. \n\nYou also have to get very good at working with editors. A good editor will hack your piece up, remove huge parts that you think are important, rephrase a lot of things (sometimes incorrectly, and you have to be able to find a compromise), and generally make it _much better_. But academics (in my experience) generally hate strong editing and are not used to it and don't like being told they're a bad writer, that they're unclear, that their argument isn't compelling, etc. Hell, we don't even like genuine fact-checking (_how dare you question my knowledge and expertise!_), but some places require you to do it. All of this is in my experience _very good_ for the piece of writing but very different than the typical academic writing experience (in which \"editing\" means a tidying up of the language and a request for a few extra footnote nodding to the right literature). \n\nAnd, of course, you must read a lot of prose by the kinds of authors you want to emulate and you must pay attention to how they do what they do stylistically. The New Yorker usually has the best historical non-fiction writing of any publication at the moment, in my experience. The works of Jill Lepore and Elizabeth Kolbert are things I pay a lot of attention to. I am a big fan of the book reviews done by Steven Shapin (in the New Yorker and elsewhere). I have gotten much out of the writing of John McPhee though his style is not one I would generally try to adopt (more journalistic). Charles Mann's _1493_ is an excellent template for a book-length popular history that both engages with academic work and tells a good story. Eric Schlosser's _Command and Control_ is another recent book that I thought was excellent in terms of balancing the expert and the popular. \n\nLastly, if you want to write well, you need to write a lot. Writing is a skill, and like all skills it is improved through practice. One does not just sit down and have great writing flow from one's fingers. The more you write, the better you'll get at it. This is one of the many reasons I advocate academics giving blogs a shot — it is a relatively low-stakes place (especially if no one reads it!) to try out different styles and approaches to writing, to developing your own personal \"voice.\" I suspect most people will not develop much of a voice in a vacuum. Writing something relatively compact (i.e., under 2,000 words) on a regular basis (i.e., a couple times a month), with attention to the writing style, will give you good returns after not very long. That sort of regular writing schedule is very different than the standard academic approach.\n\nMy [article on the Nagasaki bombing on the New Yorker's website](_URL_1_) is my personal favorite piece of writing that I've done, in part because I really knew what I was trying to accomplish from the beginning and subverted the entire piece to that. My piece on the [Trinity test](_URL_0_) was more of a \"throw a lot of things at the wall and see what the editor thinks sticks\" sort of piece — I think it _does_ hold together and have a strong theme but that came out of later editing more than the initial work."
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wrdvy | Why is it that oil seems to seep out of sealed bottles? | I've had this happen with a few different types of oils. But only with plastic bottles. | askscience | http://www.reddit.com/r/askscience/comments/wrdvy/why_is_it_that_oil_seems_to_seep_out_of_sealed/ | {
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"I suspect the oil is permeating the plastic, but I'd need to know more about the type of plastic (look for the recycle code on the bottom) and the type(s) of oils involved.",
"Also happens in glass. I got a glass tube of scented oils and left it in my car. over months it definitely had less oil in it than to begin with. Why?",
"Are you sure the oil is actually seeping out of the bottle? It is very common for bottles that contain oils to have some oily residue on the outside due to packaging and handling. ",
"Plastic engineer here, i also suspect the oil is permeating the plastic. Every plastic has a certain set of barrier properties and this varies from substance to substance, plastic to plastic. A lot of applications where high-barrier is required use multiple layers of multiple plastics to create a good barrier. It all depends on what you are trying to keep in (or keep out) of the container. I might be able to ID the bottle if you can answer a few questions: 1) is the bottle squeezable? 2) can you see through it (the plastic) 3) can you give us a picture? Right now, I am assuming you are working with a mono-layer, blow-molded bottle of either PET, HDPE, or PP."
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hqox5 | How long does a black hole take to form ? | Let's assume a supernova remnant with a mass slightly above the minimum required for gravitational collapse remains at rest in relation to an external observer. How long would it take until the observer can call the object a black hole ? | askscience | http://www.reddit.com/r/askscience/comments/hqox5/how_long_does_a_black_hole_take_to_form/ | {
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" A SNR does not collapse to a BH. Rather, the core of the progenitor of the SNR may collapse to a BH during the SN, or if the SN formed a neutron star (NS), if enough material falls back, the NS will collapse to a BH (this is all theoretical, by the way -- we have only seen end products and have to infer what happened).\n\nThe relevant timescale is the gravitational free-fall or orbital or dynamical times, which are all of the same order,\n t ~ 1/sqrt(G*rho)\nwhere rho is the density of the core of the progenitor. For nuclear densities, this all works out to order of a millisecond.",
"An infinite amount of time. According to any external observer, the amount of time infalling material (say, the surface of a collapsing star) takes to fall through the horizon is infinite. You'll only measure time to collapse if you're falling into the black hole yourself.\n\nIn this case, the *maximum* possible time from the horizon to the singularity, on the clock of the infalling observer, is πM (in units where G=c=1). This is a special case of the fact that for an infalling observer on a freefall path starting from rest at r=R, the time to hit the singularity is π(R^3 / 8M)^1/2 . This is the time a star to collapse to r=0 if we ignore pressure support from the gas.",
"Instantly, depending on perspective? It's not a black hole. It's not a black hole. It's not a black hole. Now it's a black hole.\n\nSame as death. Everyone dies instantly. You're alive. You're alive. Now you're dead."
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1whvm3 | How did Hafizullah Amin's behaviour influence the Soviet's decision to invade Afghanistan? | Here is what I have determined so far: Main factors connected to Amin's behaviour that influenced the decision
* Amin wanted to decrease his dependency from the USSR and was keen on pursuing a more balanced foreign policy by improving relations with other nations (US, Iran, Pakistan…) → USSR under no circumstances wanted to lose control of Afghanistan, a country they had financially supported from the start. They feared he would do a Sadat. (US or other western force on Soviet border… Military intelligence bases…)
* Amin completely ignored Soviet advice regarding Afghanistan’s internal and external politics (they wanted him and Taraki to broaden their support base, and Amin to share his power with his rivals, pursue more moderate policies…)
* Amin completely consolidated his power and strategically eliminated his rivals one by one. Taraki’s murder was a turning point for the Soviet Afghan policy.
* Amin’s personality is described as «duplicit, brutal...»
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1whvm3/how_did_hafizullah_amins_behaviour_influence_the/ | {
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"Amin's behavior was *the* major cause of intervention - he killed Nur Mohammed Taraki and lied about it to Brezhnev. \n\nBrief recap:\n\n* [Nur Mohammed Taraki](_URL_0_), first leader of [Saur Revolution](_URL_2_), has close rapport with Brezhnev. Being a writer, he was rather hapless at ruling, made his own share of mistakes - like premature and half-baked land reform, personality cult, but at least he wasn't as repressive as Amin. He was hopelessly naive, telling Kryuchkov, that what USSR did in 60 years, Afghanistan will do in 5 years.\n\n* Amin called Taraki \"my father and teacher\", Taraki called Amin \"my son and best pupil\". Amin quickly rose to 2-nd-in-command under Taraki and became indispensable power broker between factions and tribes. Taraki completely trusted Amin in day-to-day operations.\n\n* When Amin took over in a coup at Sep 10th, Brezhnev promised to Taraki in face-to-face meeting (Taraki was stopping at Moscow on his way from Havana to Kabul), that USSR guarantees Taraki's personal safety. He also suggested to Taraki to stay in Moscow, but Taraki went back to Kabul.\n\n* Amin was getting increasingly brutal and nationalistic - he ordered Khazara bombing raid, alienated tajiks and uzbeks from North by imposing administration of ethnic pashtuns in the North etc. Also, many army officers, loyal to Taraki, were repressed. His attempt to diminish mullahs influence among peasantry was ham-fisted and backfired. Such policies were leading to wide discontent and would clearly end in popular uprising. \n\n* USSR leadership concluded, that Amin has to be removed or Afghanistan will blow up really soon. Not all operatives supported this assessment. Chief Military Advisor Lt. Gen. Lev Gorelov, who closely worked with Amin, claims that Amin could have been reigned in and it would have worked better - see [1]. Gorelov was reassigned away from Afghanistan in November, 1979.\n\n* Two covert attempts to remove Amin from power have failed. First - to poison Amin came in very close, but Amin was saved by soviet doctor, who wasn't informed about attempt on Amin's life. Second attempt was by PDPA members - [*\"Gang of Four\"*](_URL_5_), but Amin's secretary/bodyguard Taroon took the bullet.\n\n* Amin has ordered Taraki murder (who was smothered by pillow in the Pul-e-Charkhi prison) and tried to cover up by telling that Taraki \"is not feeling well\".\n\n* Some sources have claimed (see [3]), that it was Brezhnev ambiguous reply hastened Taraki's death (\"it's your choice what to do with Taraki\"), but it there's no confirmation in primary sources, that Brezhnev has ever communicated with Amin, moreover, there are many mentions that Brezhnev was carefully avoiding Amin and any signs of official endorsement.\n\n* In fact, USSR made an inquiry about Taraki's health and Amin promised to personally monitor Taraki's health and provide all necessary means for his recovery. At that moment Taraki was dead and Amin knew it.\n\n* When Brezhnev was told about Taraki's murder, he became really upset and later insisted on direct military intervention. Also, KGB leadership supported intervention against Ministry of Defense and General Staff recommendations, although by 1983 [Andropov](_URL_4_) (he was KGB Chairman in 1979) recognized it was a mistake. KGB preferred Babrak Karmal as more pliable vs both Taraki and Amin.\n\n[Acad. E. Chazov](_URL_6_), leading USSR cardiologist, served as a \"Kremlin's doctor\" at a time and was quite close to Brezhnev. By 1979 Brezhnev has very serious health issues and saw Chazov almost daily.\n\nHere's quote from Chazov's memoirs (Brezhnev very upset about Taraki's death, that his promise to Taraki about safety was broken and calls Amin 'scum') : \n\n---\n\n(russian)\n\nБрежнев, несмотря на снижение способности критического восприятия, бурно переживал это событие. Больше всего его возмущал тот факт, что только 10 сентября, незадолго до этих событий, он принимал Тараки, обещал ему помощь и поддержку, заверял, что Советский Союз полностью ему доверяет. «Какой же это подонок — Амин: задушить человека, с которым вместе участвовал в революции. Кто же стоит во главе афганской революции? — говорил он при встрече. — И что скажут в других странах? Разве можно верить слову Брежнева, если все его заверения в поддержке и защите остаются словами?» \n\n---\n\n\n**Sources**\n\n1. *[russian - Lev Gorelov. How it happened](_URL_7_)* - interview with Lev Gorelov by Artyom Sheinin.\n\n2. *[russian - Excerpt from Protocol 172 - Oct 31, 1979](_URL_1_)* - Detailed description of Amin's missteps. Politburo has decided to plan for Amin removal.\n\n3. *Misdaq, Nabi (2006). Afghanistan: Political Frailty and External Interference. Taylor & Francis. p. 125. ISBN 978-0415702058.* - oft-cited secondary source with many factual mistakes.\n\n4. *[russian - Е. Чазов. Здоровье и Власть : Мемуары \"Кремлёвского врача\" = E. Chazov. Health and Power: Memoirs of the 'Kremlin Doctor'. Moscow: Novosti, 1992](_URL_8_)* - Chazov's memoirs wasn't translated into English, AFAIK. \n\n5. *[English - The Origins of the Soviet-Afghan War - Revelations from the Soviet Archives](_URL_3_)* - some Politburo protocols about Afghanistan translated to English (not all, though)"
]
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"http://psi.ece.jhu.edu/~kaplan/IRUSS/BUK/GBARC/pdfs/afgh/172-7910.pdf",
"http://en.wikipedia.org/wiki/Saur_Revolution",
"http://www.alternativeinsight.com/Afghan_War.html",
"http://en.wikipedia.org/wiki/Yuri_Andropov",
"http://en.wikipedia.org/wiki/Gang_of_Four_%28Afghanistan%29",
"http://en.wikipedia.org/wiki/Yevgeniy_Chazov",
"http://artofwar.ru/s/shejnin_a/text_0165.shtml",
"http://www.gumer.info/bibliotek_Buks/History/chazov/02.php"
]
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|
19im8x | What are some lesser-known consequences of Rome moving its capital to Constantinople? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/19im8x/what_are_some_lesserknown_consequences_of_rome/ | {
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"I was just thinking about one aspect of this - about how the pontic steppe over a few decades became just that bit more interesting for hordes on the other side of the steppe ocean.",
"I don't know how 'lesser-known' you are looking for. But, the Rise of the court Eunuch and transition from the 'Principate' to the 'Dominate' is pretty interesting. Also, relations with Persia became more common."
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2kl0gx | how does a bullet fit in the barrel of a gun? | if you had a bullet without the shell casings, just the raw bullet. how snug would it fit in the barrel of a gun? say i took out the barrel of the gun and put the bullet in the barrel, would it just drop straight through? would it bounce off the sides? or become lightly wedged? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2kl0gx/eli5_how_does_a_bullet_fit_in_the_barrel_of_a_gun/ | {
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"It wouldn't fit at all. Modern firearms use rifling which will dig into the sides of the bullet when fired; unless you can push it in hard enough to gouge metal then it won't go in.",
"Tightly wedged, the bullet usually forms a nearly gas tight seal that allows the pressure created by the burning powder to propel the bullet through the barrel. You can see something similar on videos of \"[slugging a barrel](_URL_0_)\" with a ball of lead and the amount of force required to force the lead through an empty barrel without gunpowder. ",
"There are good answers already, but nobody has really addressed why it's a snug fit.\n\nThe gunpowder explodes, which means it turns into gas very quickly and expands to take up much more space that is available.\n\nThese gases will take the path of least resistance and if the weapon is functioning correctly, they will push on the bullet at great speed until it's out of the way, then finish expanding through the empty rifle barrel's opening.\n\nIf there was a gap between the edge of the bullet and the barrel, the gases would just seep through that gap and exit the barrel without imparting all their force on the bullet, maybe only moving it slightly. Remember: path of least resistance.\n\nIf your barrel is stuck, your entire rifle may explode because the gases have nowhere to go, and try to break out in all directions.",
"To go into a little more detail, for most modern firearms the barrel has three separate sections cut into it. First is the chamber. This is where the cartridge is when it's fired, and it is much larger than the bullet. The bullet would drop easily through this first section without touching the sides, but probably wouldn't be so loose as to get wedged in most cases. (about 1-5 inches, depending on cartridge size)\n\nNext there is a small amount of \"free bore\", this is a short length where there is no rifling and it is basically exactly the same diameter as the bullet. The bullet would slide through this initial part of the barrel relatively easily, but without any free space. It would probably require light pressure from a finger to push the bullet through this area. (0.1-0.5 inches, usually on the lower end of this range)\n\nAfter that, the rifling begins, which is a set of spiral ridges that dig into the sides of the bullet and force it to spin as it moves down the barrel. At this point pushing the bullet through would become fairly difficult, like trying to recork a wine bottle. (the rest of the barrel)"
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5mwp6l | Was the phrases like, "once upon a time" derived from fictional stories that insisted they actually happened, during the Middle Ages? Was this a common trope of the time? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/5mwp6l/was_the_phrases_like_once_upon_a_time_derived/ | {
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"Stock phrases, including \"Once upon a time,\" were used by storytellers to let the audience know that they were about to hear a folktale, a matter of fiction. In general, western and northern Europeans told two types of stories - folktales and legends. Legends were to be believed, and folktales were the oral novels of the folk. Boundaries were often blurred so definitions are challenged by specifics, but the dichotomy is useful in classification.\n\nThe \"once upon a time\" open phrase indicated that there was no insistence that the story \"actually happened\" at any time. Similarly, these stories would end with a device to let people know the fictional story was at a close. \"And they lived happily every after\" is most familiar to modern audiences. I always liked the common Irish close: “Tá sé go máith, agus níl sé go dona” - \"It is good and it isn't bad.\"\n\nThe following is text I used for my folklore classes, excerpted from my teaching manual, [Introduction to Folklore](_URL_0_):\n\n > European folklorists, following the lead of the folk themselves, have long recognized two forms of oral tradition, Sagen and Märchen, legends and folktales. While there are many other forms of oral tradition, legends and folktales stand in opposition to one another, yet share a great deal. In reality, lines can blur.\n\n > Legends – or Sagen as the profession often prefers – are generally short, single-episodic stories told chiefly in the daytime. More importantly, the teller intended the listener to believe the story. Legends often have horrible ending to underscore the story’s important message. A large number of them are, after all, typically meant to be instructive, to serve as warnings in some way. These types of stories are not necessarily long-lived. Their point is to reinforce and prove the legitimacy of a particular belief. Nonetheless, some legends take on a traditional character, can become multi-episodic, and migrate over considerable spans of time and space.\n\n > Folktales – or Märchen, again using the German, technical term – are longer stories with more than one episode. They are restricted, in theory at least, to evening presentation. A folktale is not to be believed, taking place in a fantastic setting. The European folktale also requires a happy ending, the cliché of “happily ever after.” Any given folktale can be told with considerable variation, but they are traditional in basic form, and folklorists have spent decades tracing the history and distribution of these stories.\n\n > A word here about the term “fairytale” is appropriate. At the end of the eighteenth century, various writers, most prominently the Grimm brothers, began publishing children’s stories based on folktales. These collections became extremely popular, particularly among the urban and increasingly literate emerging middle class as it found itself removed from the peasant soil that served as home to the stories. Fairytales often cause misunderstandings. In a culture that knows more about fairytales than Märchen, people assume that the folktale was intended for children. This is certainly not the case since the stories were often violent or sexual in ways thought inappropriate for children. Indeed, the telling of a folktale was usually delayed until the children had gone to bed. While fairytales provide the modern reader with the easiest access to the many stories that were once told internationally, one should always realize that they are removed from the primary inspiration. The original stories and their content provided serious entertainment for adults and they were part of an oral tradition, not something that was fossilized in writing.\n\n > The evolution of published fairytales had a profound effect on the subject of fairies, elves, trolls, and similar entities. Because fairytales became the literary domain of children, many people – including later writers – assumed the same was true of the supernatural beings. In their original context, nothing could be further from the truth. These were not cute, diminutive creatures whose sole purpose was to delight children. They were powerful, dangerous, and capable of great harm. The European peasantry feared and respected them, and their stories underscore this, conveying in uncompromising terms the code of ethics and behavior that one must employ to survive an encounter with the dangerous world of magic and power.\n\n > The definition proposed here for “fairytale” does not necessarily coincide with how people – and even some folklorists – use the term. Some scholars regard “fairytale” as appropriate for the more fantastic expressions of folktales as they were told by the folk. The reason why the term is not used in that capacity here is because the folk did not refer to these stories as fairytales and because the term implies a degree of innocence that is inappropriate; again, “fairytale” is most suitably reserved for the published children stories that gave literary expression to the adult oral fictions of the folk.\n\n > Besides the legend and the folktale, there is also the folk ballad, a specialized form of oral tradition that, like the others, incorporated a wide range of beliefs. The ballad had roots in medieval Europe, combining narrative and song. The ballad usually focused on a single incident, and it almost always emphasizes action.\n\n > Something also needs to be said here about myth. People use this term awkwardly. In a European context, myths tend to be the artificial constructs of ancient and Classical-era priests or literate people who sought to weave folk traditions into a comprehensive whole. The exercise often had political purposes, designed to provide diverse people with a single set of beliefs and stories. By reconciling similar traditions, the shared culture of these groups could be seen as more important than the differences, justifying the central rule of the king and his priests. Myth is also a way of organizing and reconciling folk traditions, which by their nature can be contradictory and highly localized. Myth tends, however, to make gods of supernatural beings, giving those powerful entities a status – for modern readers – similar to the Judeo-Christian-Islamic God, even when this comparison is not justified. Of course, it is also important to point out that myths were stories that were told – and then written down – and they were different from religion itself. Many myths were simply the shared cultural inheritance of a group of people. \n\n > In general, the word myth is best set aside when discussing more recent folk traditions, recognizing its proper status as a literary genre. Nonetheless, ancient documents recording myths can assist in understanding the history of various stories and beliefs. The authors of these texts were, after all, the first folklorists, and they were the only ones coming close to practicing the craft at the time.\n\n > Some folklorists carelessly use the term myth to denote those legends that deal with a fantastic, remote time. This primal era saw the creation of many familiar things such as day and night, fire, animals, people, mountains, and all other aspects of the present world. Folklorists properly refer to these stories as etiological legends explaining the origin of things. Sometimes, however, people interchange etiological legends with the word myth. The problem with this is that “myth” can imply something that is inherently wrong, linked to “primitive” superstitious beliefs. When the term “myth” is used for the folklore of existing cultures or for the traditions that were viable only a generation or more ago, it can take on an insulting, derogatory tone. It is best to reserve the word “myth” for ancient and Classical-era texts.\n"
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26ov6b | - the difference between using a computer as a server versus using a computer to complete everyday tasks? | I saw a post on r/techsupportmacgyver where a user augmented a laptop into a server. What was going on? Why would someone remove the screen to their laptop?
Also, my friends will talk about servers they had in high school, but I always see these huge server rooms in the media. There is no way they had all that, so what in the world could their use have been. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/26ov6b/eli5_the_difference_between_using_a_computer_as_a/ | {
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"A server is just a name for any computer that provides any kind of service across a network. The server can be a multimedia server (providing music and video streaming), a web server (hosting a website), a file server etc.\n\nThe only requirements for such a computer are that it will always be online and connected to the network (it should also be a powerful computer that can serve many clients at once, but that's not a requirement). Because all the communication with the server are performed through te network, it doesn't require any other input/output devices, such as a screen or a keyboard.\n\nAs to the post you're talking about (which I'm assuming is [this](_URL_0_)), he explains in the album that he removed the screen so that the laptop would take up less space and could be placed vertically.",
"There are two main ways that computers can communicate with each other: using connectionless protocols, which are generally stateless, and using connection-based protocols, which maintain state. The main connection-based protocol in use is called the Transmission Control Protocol, or [TCP](_URL_3_).\n\nIn the TCP, one computer acts as a server by listening for connections. Other computers then act as clients by *connecting* to the server. Once a client is connected to the server, they can communicate via that connection until it is closed. A server will typically maintain multiple connections to several clients at once. Even though it was originally stateless, for other reasons that I won't go into, the web uses TCP rather than a stateless protocol. A web server listens for connections from clients, which is what your web browser is.\n\nMost computers have several services running on them which listen for connections, so in that sense, most computers are servers, but a *dedicated* server is typically a computer whose *main function* is to run a particular piece of server software to serve clients. Usually things like web servers are run on dedicated servers. Because the main purpose of a dedicated server is just to run server software, there's usually no need to have a display, a mouse or a keyboard attached to it. When you need access to the server, you usually just use remote control/access software. That's why the screen from the laptop was removed.\n\nA dedicated server can be anything from a piece of junk tower sitting under somebody's desk, to a state of the art machine running in a huge data center. Most dedicated servers used for anything serious are [rack mounted](_URL_1_), meaning that they are housed in flat, deep cases that slot into a rack. When you have a rack full of servers, they start to run very hot, so you usually require cooling and air conditioning. Furthermore, with many servers, you'll also have lots of Ethernet cable and networking equipment. Managing all of this cable, networking equipment and cooling is something that a data center is good for.\n\nWhere I work, we have a single rack with about 10 servers in it, so we just have a small air conditioned room that we keep them in. Companies such as Google have so many servers that they have many huge data centers the size of warehouses. The kind of server room you probably find in a typical high school is probably just a few dedicated towers in a closet somewhere.\n\nMany servers run the [Linux](_URL_2_) OS, though some run Windows too, and even [Solaris](_URL_0_).",
"The high school servers they were talking about were probably just an old pc that they connected to their router, and stored music, films etc on it. That way all the people living in a house can access it, and the stuff that's on it.",
"A server is just that a computer that erves. Other computers connect to the server over a network either the internet or just a local network these are known as client computers because they are the ones getting served. A client request some data from the server and the server sends it. The most common example of course being servers for websites. Your computers web browser basically asks the website for the data stored (generally html file) store at the location of the url and the server provides that data.\n\nIt could also be as simple as you having a computer in your house that serves as a media center for the rest.",
"Server and workstation are just descriptions of what the machine is being used for. There's no reason you couldn't turn a workstation into a server, and vice versa. In fact, a computer can be both server and workstation (like if you share files or run a small game server on your desktop you use for gaming/web browsing, for example).\n\nIn practice, a computer designed to be a server will be different from a computer designed to be a workstation. In a server build, you typically value CPU and hard drive specs (size, speed and quantity). In a workstation, you'll put more value into GPU and will probably have something better than dirt cheapest i/o (keyboard, mouse, monitor, etc.).\n\nIt is possible to have a server that can only be controlled via network (no video, no input except network), which would make it unusable as a workstation."
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1os7xr | why do 99% of toothpaste/mouthwash have dyes? | They're for cleaning teeth. Coloring = stain teeth. Is this not true? What's everyone's problem with making dental hygiene products? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1os7xr/eli5_why_do_99_of_toothpastemouthwash_have_dyes/ | {
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"The dyes aren't able to alter your teeth or anything. When you put food colouring in cake batter it doesn't change the cake batter in any way, it just puts molecules of a liquid that reflects a certain colour around the molecules of the batter.\n\nIf you put such colourings on your teeth they can't get mixed into your tooth the way they can with a loose material like cake batter or toothpaste, it just falls off. Maybe a little bit holds on thanks to hydrogen bonding or something, but it'll come off without much fuss if you run your tongue over it or just get saliva moving over it. "
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492nvv | where does the us dollar get its value if there is no gold standard? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/492nvv/eli5where_does_the_us_dollar_get_its_value_if/ | {
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"supply and demand within the country itself, and other countries/foreigners?",
"the same place, essentially, that ANYTHING get's it's value from: popular consensus. Anything on this earth has value because people have all agreed it has value, whether it's gold, gem quality diamonds, milk, or dollars. That value is usually (but not always, gem quality diamonds for instance ain't that useful) a function of the usefulness of the thing. \n\ngiven that dollars are \"legal tender\", they are quite useful.",
"Supply and demand impacts the value of the U.S. dollar. The dollar increases in value when dollar demand goes up and loses value when dollar demand goes down. When the US imports stuff, the value of the dollar decreases because the US has to buy foreign currency to pay for its imports. Strong U.S. exports increase the value of the dollar countries have to buy more US dollars to do trade. At a deeper level, the commodity that impacts the buying and selling of dollars for trade purposes most heavily is oil, leading toward the concept of the 'petrodollar'.",
"As a reserve currency, the US dollar is the default for international transactions. If, for example, a South Korean company wants to buy wine from Chile, chances are they will carry out the transaction in dollars. Both companies must then purchase dollars to conduct their business, leading to greater demand. The value of global commodities, such as oil, is also generally demarcated in US dollars.\n\nBeing a reserve currency allows the US to borrow at low interest rates, as central banks around the world are eager to buy US government debt. \"Any country that can finance its expenditures by printing money or selling bonds is essentially getting a free lunch,\" ",
"The only way you can buy US goods and US services is with US money. The high demand for both is what gives our currency its value.\n\nAn easy way to think about it is that the money is backed by our economy, rather than a commodity.",
"Since there is no gold backing of the USD, the value is determined by the use of USD in circulation and foreign exchange. The US gov will only use USD when purchasing things like foreign oil, and other imports. IF/When countries decide to stop accepting USD for payment, the value goes down. ",
"Where does it get it's percieved value, or it's actual international value. The actual value comes from simple supply and demand across currency exchanges. If a lot of people want dollars, whether it be for speculation, or for the normal reasons (the purchase of goods and services). As for the perceived value, a lot of it comes from Oil Trading. Until recently, the only currency crude oil was traded in was US Dollars. This meant that in order to buy oil, you had to buy dollars, and if you sold oil, you got paid in dollars, thus keeping demand high. During the Bush Administration, Iran built an exchange, that runs on Euro.",
"The dollar gets its objective value in at least two ways.\n\n1. The US government accepts only dollars to pay taxes. If in their opinion you owe them you need dollars to keep them from sending men with guns after you. \n\n2. American workers must be played a minimum number of dollars per hour worked or the aforementioned men with guns show up. \n\nSo, instead of gold it's now based on the value of unskilled labor and the convenience of not having the US government's men with guns after you. ",
"It appears that you're not really asking a question rather you are trying to prop up your own viewpoint, so I'll ask you a question. Where does gold gain it's value from? ",
"The US dollar gets value through acceptance. If a narrower set of people start using the dollar and people start dumping it for other currencies, its value will go down and scarce goods become more expensive.\n\nForeign exchanges will start demanding more dollars if people start dumping the US dollar. People will start offering more dollars to foreigners looking for US dollars in an attempt to get rid of there dollars faster. This can cause hyper inflation because the demand for goods rises.",
"The full faith and credit of the united States Treasury and the laws that require Americans to accept US Federal Reserve Notes as payment for debts. They're also unique compared to other forms of money in that they're not subject to capital gains taxes. For example, if I owned gold or some other commodity and the value of the dollar decreased the gold would be worth more dollars even though it would have about the same purchasing power. But I would be taxed on the nominal dollar increase in the price of the gold. However if I saved some dollars and the value of the dollar increased I would now have greater purchasing power but because am taxes are calculated in units of dollars I wouldn't have to pay any taxes on the increase in value. Like most goods or money, the value of dollars is determined by their scarcity. If the US decides to just print tons of more money the value will decrease.",
"First of all it doesn't really have value in the same way that a commodity or service does. Its just a medium of exchange. You could replace all the paper money with a master ledger somewhere and we'd be no worse off. The economy has a certain level of output and we use dollars to account for who owes what to who. Rather than some weird barter system or one where everybody writes everybody else IOUs we have a common currency. The federal reserve controls the amount of dollars and keeps their value consistent against a basket of commonly bought goods. So when you agree to work for a dollar essentially you're agreeing to trade your labor for some share of that basket of goods. So in a way we have a basket-of-goods standard I guess.\n\nThe gold standard on the other hand is a little different. Gold obviously has some practical uses in jewelry and circuits but most of it just gets hoarded. Its attraction as far as money is concerned is that its rare. For centuries (and even today to some extent) counterfeiting coins and paper money was easy enough that it could bring the whole system down. But you can't counterfeit gold because there's only so much of it on the known earth. So a gold standard created a relatively fixed money supply in primitive economies. The problem is there are times where you actually want to expand or contract the money supply because not doing that will lead to deflation or inflation. Gold doesn't allow for that. In fact gold tends to become more valuable during downturns. In a recession there is a natural tendency to get deflation and the gold standard would exacerbate that - making recessions worse. ",
"The dollar gets its value from the US government. The government literally creates dollars (by printing them), and gives them value by accepting them as payment, e.g for taxes. The government can raise the value of the dollar by selling more things, such as financial instruments, in exchange for dollars, which makes dollars more scarce and desirable. And everyone believes that the US government can and will maintain the value of the dollar, because the US is such a large economy, and the government wants to maintain this economy and can extract financial resources from it if needed, via taxes.",
"I had this explained to me a couple years ago when I first started in on my economics degree and it revolutionized my understanding of money.\n\nThe first thing I want to ask you is what IS a dollar? Dig deep on this one. Take a minute to think about it.\n\nReally, that dollar is anything you want it to be. It's a cheeseburger. A skydiving trip. Rent. Maybe a new dog.\n\nSo what is the dollar? Well its a measurement of your own capacity to make a decision. Any decision.\n\nBut why do we have a dollar? Couldn't we just barter like our ancestors?\n\nWell sure. We could. But let's create a hypothetical economy where I provide sliced bread. And you provide sliced ham. We trade bread for ham, everyone wins.\n\nBut what if you provided shoes. But I already have shoes. So I don't really want to buy anything from you but you still want my bread. Wouldn't it be better if there was some other thing that held value and allowed us to make our economic decisions?\n\nBut why the dollar. Why the gold standard? Well, now that we've established why we need a currency we should talk about what makes a GOOD currency.\n\nWe've all heard the stereotype about cigarettes being legal tender in prison. But cigarettes are a bad currency. You use them. Cigarettes don't hold value over time. Aztecs used to use cocoa beans. Which obviously have the potential to go bad. So it stands to reason that a GOOD currency would be somewhat useless. And a good currency is physically stable over time.\n\nEnter gold. Gold is relatively rare. So it takes effort to get. Other than shininess, it doesn't have a whole lot of useful attributes. And it doesn't oxidize over time. (or do much else for that matter) gold was a good choice of currency because of how utterly useless it is. \n\nBut when and why did we get rid of the gold standard. You're probably gonna read a lot of nitpicky political reasons for why the gold standard was abandoned in the way it was and at the time that it did. But the reality is is that with the advancement of technology, gold was no longer meeting our already established definition of a good currency. Gold is a key component in most electronics. Which as you probably know. Are used by lots of people a lot of the time.\n\nSo we moved to a fiat currency. Where the dollar has value simply because we say it does.\n\nWhich really, is kind of how it already worked for a long time anyways. We just formally acknowledged it.\n\nDon't believe me? How much are you worth right now, on paper? Chances are that value is higher than the value of your pocket. I.e. you don't have all of your money on your person directly. You have it at the bank. Most of the time that bank doesn't have all of your money that you put in the bank, in the bank. The bank is off doing other shit. Taking your money for long walks on the peach. Singing it love songs. Whatever. It's not in the safe.\n\nNobody's money is in the safe. Except a small amount that's enough to get by.\n\nBut the system works fine most of the time. Because we have faith in the bank. The word \"credit\" comes from the latin word \"to believe\". All the gold standard ever was was saying that if qthings went belly up, the value of the money in the bank was backed by gold. Not that you'd be able to get gold back in the event of a run on the bank. Bank never had enough gold for that. That's just not how they do business. But the value of the money wouldn't erode. Which could be just as easily accomplished by having a dollar without backing by just assigning it a value. But it would be a lot easier without the need to get gold wrapped up in this for some reason.\n\n\nTl;dr the gold standard wasn't really the necessary in the first place and it outlived its time as technology evolved to change the role of gold fundamentally ",
"It has value because people have confidence in it even though it has no intrinsic value and is not backed by anything. In other words, a confidence game."
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34wgv1 | Is there any known limit to how old a tree can be? | Watching planet earth and it was talking about how old the forrests of the northwest are, which made me wonder. If there is no outside threat, and given unlimited resources how old will a tree become? | askscience | http://www.reddit.com/r/askscience/comments/34wgv1/is_there_any_known_limit_to_how_old_a_tree_can_be/ | {
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"They cut one down a few years ago that was several thousand years old thought to be the oldest known living creature on Earth. Even if trees by today's standards can't live forever, maybe lets say they could be genetically disposed to live forever by genetic change. There's that sea polyp that they say doesn't age. Then you're just talking about the tree surviving until the sun starts running out.",
"As far as I learned in my college botany and biology lectures, most plants depend solely on resources and environment for their longevity. If environment is favorabel, and all nutrients are available, plant can technically live forever. That is why plants are good for cell cultures.",
"I suspect it really depends on what you mean by \"tree,\" \"old,\" and \"outside threat.\" Bear with me a bit in trying to explain this as best I can, while constantly remembering that *senescence in trees (and plants in general) is relatively poorly studied (when compared to animals) and a topic of debate in research circles.*\n\nLiving, single trees seem to be able to survive for about 5,000 years, at maximum, for *Pinus longaeva*, the Bristlecone Pine. I believe the oldest known single living tree specimen is [a Bristlecone in the White Mountains of CA.](_URL_4_) There have been other well-known and studied Bristlecones which also cluster in maximum age around 5,000 years, and this seems to be at the limits of what we can call well-established and verifiable old ages for trees. Most other species, of course, in the US and elsewhere do not grow nearly as old (you can look further down on the Oldlist I linked above; also compare to [the \"Eastern Oldlist\" available here](_URL_2_)).\n\nThere are also clonal trees (and even vines) which exhibit the ability to be *much* longer lived, although it is impossible to precisely date such colonies. Examples are cultivated grapes (which in Europe have been propagated from constantly-living rootstock of more than 800 y.o.). It is generally considered true that for at least some plants, ageing does not seem to affect the ability to create new viable somatic or germline tissues. This means that there doesn't appear to be any *absolute* genetically determined, cell-level senescence that reduces viability over time (as there are in most animals). This is supported by the existence of oldest-known tree (clones) like the \"Pando\" aspen, a clonal *Populus tremuloides* colony in Utah, which has been [estimated as being between 40,000 and 1,000,000 y.o.](_URL_1_) The actual ramets (individual quaking aspen 'trees') seem to have maximum ages around 130 years, but the connected rootstock is thought to be around 80,000 years old and constantly producing clonal ramets. [Some authors say it's impossible to date Pando, or even determine that there is only one clonal line in the colony,](_URL_5_) so the (estimated) age is debated. \n\nThere *is* good evidence, from single tree studies, that there is a relationship between age and size that limits growth and leads to reduced vigor. In other words, [when a tree reaches a certain age-size combination \\(that would be specific to species and environmental conditions\\), it is likely to stop growing and eventually stop reproducing effectively.](_URL_0_) This is likely due to certain biophysical limits for trees (i.e., efficient water transport becomes impossible for a certain mass and height of a tree due to hydraulics, and maintaining structural integrity becomes impossible at certain widths, heights, and trunk configurations). Anyone that has ever lived in a place where [*Acer saccharinum*, or Silver Maple](_URL_3_), is planted or common knows that they grow to a certain size and age (about 60-100 years old) and then start to fall apart when someone looks sideways at them (or the wind blows). \n\nPlant cells and tissues *can* age and die, as meristems accumulate genetic damage. There is evidence, however, that in long-lived plants (trees and some perennial shrubs), there are alternating cycles of tissue death and growth (replacement) that modify the effect of this on whole plant health. This is partially why you find healthy, living hollow trees with living and dead tissue. There are also selection mechanisms so that genetic repair and pretty sophisticated methods for dealing with somatic mutations result in it being the case that [\"most plants do not age in the strict gerontological sense.\"](_URL_6_) \n\nIt's worth noting that most of the really *old* trees known (Bristlecones, certain figs, Bald Cypress, etc.) are usually dying. I don't think there is a lot of empirical evidence that trees can 'live forever,' although we may not have pinned down mechanisms (other than limitations imposed by biophysical context, like water and nutrient availability, structural damage from the environment, etc.). \n\n----------------------\n\n\\***tl;dr**: *Many plants don't have the same type of cellular-level senescence that is common in animals, or have genetic repair mechanisms to reduce the effect of somatic mutations. Long-lived species of trees can apparently live for a very long time (5,000+ years), but appear to be limited by a size-growth interaction. Environmental conditions (damage from disturbance, nutrients, water availability) provide 'absolute' limits for growth and age of species. Clonal species (like Quaking Aspen) can technically 'live' for very long times, possibly as much as 80,000 years or more.*\n ",
"While many trees have no \"age limit\" outside of disease, lack of resources, or other external causes of damage and death, some trees do have finite lifespans. Peach trees in particular have exceptionally short lives, only living 10-15 years ([Wiki ref](_URL_0_) says 12 years). Other types of fruit tree apparently also tend to be short-lived, with [this reference](_URL_1_) saying 12-60 years for various types. There are probably other short-lived species as well, but I didn't manage to find a good list. "
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[],
[],
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"https://www.researchgate.net/profile/Maurizio_Mencuccini/publication/50212240_Size-mediated_ageing_reduces_vigour_in_trees/links/5443ff550cf2e6f0c0fb9b5f.pdf",
"http://www.nature.com/scitable/knowledge/library/case-study-the-glorious-golden-and-gigantic-13261308?refnf",
"http://www.ldeo.columbia.edu/~adk/oldlisteast/",
"http://www.na.fs.fed.us/pubs/silvics_manual/volume_2/acer/saccharinum.htm",
"http://www.rmtrr.org/oldlist.htm",
"http://courses.biology.utah.edu/seger/2005/Mock_2008_ME.pdf",
"http://sidney.myzen.co.uk/pdf/paperpdfs/098.pdf"
],
[
"http://en.wikipedia.org/wiki/Peach",
"http://www.grit.com/farm-and-garden/growing-fruit-trees-zm0z12jfznem.aspx"
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t9gst | Why is it hard to find a star system with 9 or more planets? | I just read this article (on the bottom). Is it rare because there's a low probability it would happen, or are our telescopes not good enough to see individual planets that well?
_URL_0_ | askscience | http://www.reddit.com/r/askscience/comments/t9gst/why_is_it_hard_to_find_a_star_system_with_9_or/ | {
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"If you take our solar system as an example it becomes easy to recognize why we haven't identified very many solar systems with large numbers of planets. It's not because it's any less likely that they exist, but rather the most popular method we use to identify extra solar planets isn't conducive to quick identification.\n\nThe Kepler Space Telescope uses the transit method which measures the brightness of a star over time looking for minor dimming in the amount of light that occurs at a predictable rate. This requires that a planet complete multiple orbits before it's possible to suggest it actually exists.\n\nBecause larger solar systems typically have planets spread at different distances from the parent star it's reasonable that some of those planets will have very long orbital periods. This translates to the simple explanation of time. With time we'll likely discover even more solar systems with large numbers of planets."
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1l65uq | how is adblock still active? wouldn't big companies try to take them down? | When I did my search, all I could find was that AdBlock is completely legal because it is modifying page on the user-end. But big companies who live off of selling and showing ads need the ad to be shown and clicked to survive. I'm sure its no match for fully donation-run adblock to compete against those big multinational companies? How are they still thriving? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1l65uq/eli5how_is_adblock_still_active_wouldnt_big/ | {
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"Relatively few people use AdBlock, and the tech savvy crowd that uses it is relatively unlikely to click on ads anyways. If more people started using it, you can bet that ad based companies would try to take them down.\n\nAlso, big companies don't need to take them down at all. Google banned AdBlock Plus from their Google Play store, but the also paid AdBlock Plus to allow some of their ads through.",
"Kind of the opposite, but when I hate a company, I click on every one of their ads because they typically have to pay for the click. It is my little way of costing them money 1/100th of a cent at at time. \n",
"...and how would they \"take them down\"?\n\nIt isn't like a war with guns. The big companies can't take them down because they have no legal right to. There's no way for them to do it in a legal way, so they can't and won't.\n\nI'm not sure what else to explain about it. It's just...entirely legal, is all.",
"Ask everyone you know if they use Adblock. You'll be astonished at the amount who don't. I know for sure my neighbor doesn't, and my sisters and brother don't, and neither does my mom. I think my GF doesnt either. \n\nI actually don't always use it either, because I feel it's important to support the developers and the sites I enjoy. Ads don't annoy me that much and I rarely click them, however I will block very intrusive ads when they start getting to me."
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42gol7 | How did native Floridians handle mosquitos? | Having lived in Florida the past 20 yrs, I'm accustomed to mosquitos being a part of life. My question is how did native Americans that lived here deal with mosquitos being that they didn't have a concept of "indoors", aside from open air living spaces? Did they not care about getting bit or is it known if they had their own way of combating the bugs? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/42gol7/how_did_native_floridians_handle_mosquitos/ | {
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"While I can not answer this question, I believe [this thread](_URL_0_) has information pertaining to what you are asking.",
"This is an interesting topic. No expert, but my source is Marjorie Kinnan Rawlings's autobiographical book *Cross Creek*, which talks about using a smoky fire to keep mosquitoes away. I know we did the same at beach parties and cookouts in New England. \n\nPerhaps a better historian can address this: in preparing my lecture on the history of sexual norms and coming across information about colonial indentured servants, I read that due to factors such as mosquitoes and malaria (not to mention snakes, bears, panthers, and, I imagine, other criminals), the average life expectancy of an indentured servant in the Gulf region of the southeastern US was roughly two years.\n\nI'll be interested to see what more expert sources have to say.",
"I just happened upon an old post that mentioned it:\n\n_URL_0_",
"Just jumping in to recommend J.R. McNeill's \"Mosquito Empires\" which explores the disease ecology of the 19th century Caribbean. Really good book."
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5vf5wz | why is the liquid level inside a straw is higher than the liquid level in the rest of the glass? | I'm going to include a photo to clear up confusion | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vf5wz/eli5_why_is_the_liquid_level_inside_a_straw_is/ | {
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"It's because of capillary force. Water tends to climb up surfaces a little. Water also loves to stick to itself. So outside the straw, the water gets pulled up a little, but also gets pulled down by the rest of the water, so you will only see a little 'bump' right around the straw if you look very carefully. Inside the straw, There is almost as much water touching the straw, but there is less water interacting with those molecules actually touching the straw, so you have the same force distributed to fewer molecules. So the water level inside the straw will be just a little bit higher.",
"This effect is called Capillary Action. It happens because water molecules are, in a sense, \"sticky\". They cling to themselves and other materials. Capillary Action occurs when the water wants to stick to the plastic of the straw more than to itself. It's more noticeable in a straw because the straw has a very high amount of surface area and a very small diameter. Basically, inside the straw there's a lot of surface for the water to cling to but not a lot of space inside so that the weight of the water can pull it back down. Capillary action can be seen on the side of the glass as well but since the glass is very wide there is much more water pulling back down than there is glass surface to pull up."
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274md5 | Are the electric and magnetic components of an electromagnetic wave really in phase? [Physics] | Hello /r/AskScience!
Lately, I was really surprised at [what wikipedia says about electromagnetic waves](_URL_0_). According to them, the electric and magnetic components of the wave should be in phase. I can't help but think that this is wrong.
Shouldn't both components be shifted 90 degrees apart? After all, the electric field results from a change of the magnetic field, and vice versa - which implies a phase shift between the two.
What am I overlooking?
Thanks!
P.S. Of course, the two fields are in two separate planes, rotated at 90 degrees. This is something different. What I don't understand is why there should be no phase shift between the two. | askscience | http://www.reddit.com/r/askscience/comments/274md5/are_the_electric_and_magnetic_components_of_an/ | {
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"Both are in-phase means that both reach the minimum and maximum amplitudes at the same time. However, their direction of oscillation is perpendicular to each other as well as perpendicular to the direction of the wave.\n\nChange in the electric field produces a change in the magnetic field and vice versa. This results in the same phase shift for both the fields.\n",
"No, the wiki page is right. The two oscillate in sync. One way to see this is to write down Ampére's and Faraday's laws in vacuum, which (in differential form, cgs units) are: \n\n∇ x **B** = (1/c) ∂**E**/∂t\n\nand\n\n∇ x **E** = -(1/c) ∂**B**/∂t.\n\nTake the curl of the first equation, use that ∇ x (∇ x **B**) = -∇^2 **B** (no monopoles), substitute the second equation, and you get \n\n-∇^2 **B** + ∂^2 **B**/∂t^2 = 0,\n\nwhich has plane wave solutions \n\n**B** = **B**_0 exp( i **k**.**x** - i ω t) + \"c.c.\" \n\nwhere ω/|**k**| = c, **B**_0 is a constant vector, and \"c.c.\" stands for the complex conjugate. Now assume that the electric field also has a wave-like solution with a possible phase shift φ\n\n**E** = **E**_0 exp( i **k**.**x** - i ω t + i φ) + \"c.c.\"\n\nIf you substitute this wave solution into Ampére's law (the top equation), then you can see that this is solved by φ = 0 with the vectors **E**_0 and **B**_0 obeying\n\n**k** x **B**_0 = - ω/c **E**_0 \n\nor rather, \n\n**E**_0 = -**k**/|**k**| x **B**_0.\n\nIn other words, **E**_0 and **B**_0 have the same magnitude in these units, are orthogonal to one another, and the two waves oscillate in phase with one another. \n\nEdit: formatting",
"Even if the two answers already given are mostly right, you are also right in some kind of way. \n/u/__Pers only talks about plane waves - this is okay as an mathematical abstraction, but you can't \"produce\" plane waves, as they have to be infinitely extended in time and space. \n\nIf we think about creating an em-wave, we use the model of a [dipole](_URL_0_), that periodically oscillates. You can imagine two charges (one positive, the other negative) that start resting at two positions with a distance d, start accelerating towards each other, pass each other and stop at the same distance as before. \nThis will produce electromagnetic waves - each time both particles are at rest, the magnetic field in their direct proximity is zero (note, that due to the retardation of the em-field, it is not zero everywhere) and it is maximal, when the particles are passing each other. \nFor the electric field it's exactly the other way around - the closer the particles are, the weaker the electric fields, as their charges cancel each other out. \n\nSo the emitted wave will indeed have a phase difference of pi/2 (or 90 degrees if you like it better this way).\n\nBut if you do the whole math, which includes dealing with the [retarded potentials](_URL_1_), you find, that this is only one component of the radiation - and it's only dominant in the direct proximity of the dipole. If you measure the fields far away from the origin of the radiation, the relevant components will indeed be in phase. \n\nNow, it's a long time ago that I really did those calculations - so I can't really find an enlightening argument, why the fields should behave this way. I hope, somebody can chime in and help me out. ",
" > After all, the electric field results from a change of the magnetic field, and vice versa - which implies a phase shift between the two.\n\nWell... not really. Maxwell's equations actually say that a temporal change in the magnetic field produces a spatial change in the electric field, and vice versa. The only way for that to work is if the waves are in sync, with no phase difference. /u/__Pers has given [the proof](_URL_0_).",
"There is a difference between the near field and far field of a EM dipole. What you are saying is true for the near field: Electric and magnetic fields are shifted in phase. But the magnetic fields die off faster than the electric ones, so the behaviour is different in the far field, where they are in phase.\n\nA different case would be a standing wave: There you always have two components shifted by 90°. For sound waves, it's pressure and speed, for EM waves it's E and B field."
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1dzwli | why is it that i can use the same chocolate chip recipe but come out with varying results each time? | I use the same recipe, bake them for the same amount of time at the same temperature, and sometimes they come out perfectly soft and delicious, and sometimes they come out more airy/hard/etc. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1dzwli/eli5_why_is_it_that_i_can_use_the_same_chocolate/ | {
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"Assuming you really use all the same stuff, and do it all exactly the same (which I'm skeptical of) then one remaining difference is ingredients. It's possible some ingredients that are older (or newer) will behave somewhat differently, baking soda for example changes over time.",
"Gluten! Assuming your ratio of baking powder and baking soda and acid/base balance are exactly by the recipe and always consistent - if not fix that first - then the likey culprit is gluten. Flour can get more chewy and harder if you mix too much or get brittle if not mixed enough. It's why those chewy pizza doughs get all sorts of kneading while flakier biscuit type doughs get barely more than one turn. So for cookies, once the wet meets the dry, the texture will vary directly with how much mixing you do. Mixing just enough to get the dough wet wil make crumbier cookies and mixing for an hour will make rubber.\n\nAlton Brown had a good episode where he made three different styles of chocolate chip cookies with the same base and does a fantastic job explaining he interplay between the ingredients along the way. [3 chips episode]( _URL_0_)",
"Butter temperature. Cold will make the cookies come out a little cakey, too warm will make the oily, room temperature (70 f) is juuuust right.",
"Depending on the fat you're using, temperature matters! If the butter you use in the cookie is too warm before you put it in the oven, the butter will melt before the cookie rises, and it will spread out and feel crunchier. If you keep the butter (really, all of the dough) reasonably cold before you put it in the oven, it won't melt as quickly, which will greatly improve the shape/texture.\n\nEdit: small change for accuracy (water doesn't melt :P)",
"Well, in your case it sounds like you're baking them more than they should be baked, but it's still that human element. Tiny differences in how much of each ingredient you add will make all the... difference. Also, baking at a higher temperature for a shorter period of time is a bad idea."
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eujeje | how does seltzer water have a taste when it has no calories/sweeteners? | I know people make fun of la croix having no flavor but it and other seltzer waters obviously taste like something! As an active seltzer lover, with new brands and flavors coming out all the time now, some of these are objectively quite flavorful and sweet. Yet, they have 0 calories, 0 sweeteners or sugar, only “natural flavors.” Do they really have 0 of everything or is it just such a small amount that they call it 0?
eli5 what natural flavoring means and how it can taste so strong with no sugar or anything so I can enjoy my seltzer without mental turmoil. Thank you! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eujeje/eli5_how_does_seltzer_water_have_a_taste_when_it/ | {
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"There is still some sweetener that comes from the \"natural flavors\" they use. Its just that theres non extra sugar or anything recognized as a high intensity sweetener by the FDA.\n\nRegulations also allow you to put in less than some certain amount of calories (I think 5 per serving) and still call it 0 calorie.\n\nAnd sorry, but natural flavoring just means that it started off in plants or animals and has only had certain specific chemistry done to it. Much of the time its not directly related to whatever the flavor is supposed to represent.",
"Calories listed on food items are calories that are usable by the body. Take water for example, water has 0 calories but they still have bonded oxygen and hydrogen molecules. So there must be energy there. But the body doesn't break down those molecules hence 0 calories. \n\nSo certain things like the sweetener may contain calories but not to humans because we cannot process or absorb them. Or we can absorb them but they have very little calorific value. In some drinks, where sugar isn't used, a protein called aspartame is used. This is much sweeter than sugar and has a much lower calorific value since proteins broken down to amino acids and processed by our body only give us about 4 or less calories per gram. *and there's less than a gram in these drinks*\n\nThe FDA also counts anything that has less than 5 calories to be 0 calories.\n\nAs for natural flavours, I don't know. Maybe it is just fruit extract or something?",
"I don't think anyone has mentioned this yet so here's my go. Seltzer will *still* taste something even if it has nothing added to it. Carbonated water alone should have a flavor. Carbnonation works putting a drink under CO2 at high pressure, which forces some of the CO2 to dissolve into the liquid as carbonic acid. This is reversed when you crack the bottle and let the pressure off, but there is still some amount of carbonic acid in the drink as long as it's fizzy, and this will have a sour taste (sourness is essentially the perception of acids).\n\nThat said, there are probably a bunch of other things added that have zero or negligible calories as others have mentioned, like minerals and such.",
"FDA does not require food companies to disclose the ingredients creating a “natural flavor,” so long as they all fall into the GRAS category chemicals “generally recognized as safe.” \n\nEssential it may very well contain sugar and other artificial ingredients, just less than they are required to display. Their own website says it's made from fruit essence, fruit contain sugar so it probably has some, just enough to taste but not enough to regulate."
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2u42c2 | Would having the earth's landmass more concentrated on one side in Pangaea have had any effect on its orbit? | I think the answer is no but I was just wondering. Would the tides have been more noticeable? | askscience | http://www.reddit.com/r/askscience/comments/2u42c2/would_having_the_earths_landmass_more/ | {
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"Not on the orbit, but certainly on other dynamics like the length of day. I recently read a paper on the effect the melting ice caps are having on the period of the earth's rotation (due to the redistribution of mass on the surface). It's a *tiny* effect but there definitely is an effect. So whilst I'm not in the position to say what effect that would be, I do think it would have a measurable effect."
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7nv7cu | how does euler’s formula connect real and imaginary numbers? | I see Euler’s formula pop up and we just have to accept that you can split a complex number into real and imaginary parts using exp(). How does it actually work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7nv7cu/eli5_how_does_eulers_formula_connect_real_and/ | {
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"The best explanation I've ever seen is in Feynman's lectures on physics. One of the chapters is a condensed and exceptionally written presentation of algebra. It ends with the equivalences between complex exponents and trigonometric functions. _URL_0_"
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um7cp | Where does the matter that comprises the structure of a plant come from? | More specifically, I'm sitting here looking at the Aponogeton in my Betta's tank. It was simply a tiny bulb that was dropped in the water on top of the substrate. No soil or anything for the plant to feed on, just water. Nevertheless, out comes a massive plant. Is the plant mostly water and all of the structure derived from that tiny bulb? Seems impossible. | askscience | http://www.reddit.com/r/askscience/comments/um7cp/where_does_the_matter_that_comprises_the/ | {
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"Most plants get most of their structure from molecules in the air. Some from the soil/rocks/sand/etc and water. Remember that your water in the tank won't be pure H2O. It will have lots of other elements mixed in with it. I don't know about Aponogetons, but mixing in air with water is usually a vital step to keep a tank healthy, and that brings in all sorts of nutrients from our atmosphere.",
"With a couple exceptions of a few plants that are composed of largely water, it's air. Plants take up nutrients/minerals, nitrogen and water through their roots, but the bulk of the matter in a plant comes from the carbon and oxygen 'fixed' through photosynthesis from the surrounding atmosphere. \nThere's a good quote, that I'm paraphrasing: \"Trees are bags of air held together by sunlight. When you burn a tree you release the matter back into the atmosphere, and the sunlight back as heat and light\"\n",
"[The Feynman explanation](_URL_0_)",
"Carbon from CO2, nutrients from fish poop, and water."
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32uqmq | Prominent Bolsheviks must have read Lenin's testament, so why wasn't Stalin removed from key roles? | Stalin's Rivals must have been aware of Lenin's call to remove Stalin from the party. So despite Lenin's will not being published, why was he not kicked from the party, or removed from important roles?
I've just been revising my history AS Level and this really began to niggle me, so if anyone could enlighten me I'd appreciate it! | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/32uqmq/prominent_bolsheviks_must_have_read_lenins/ | {
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"Lenin's Testament was a profoundly embarrassing document in which Lenin insulted not only Stalin, but all of Stalin's rivals. Stalin, Kamenev, Zinoviev, Bukharin, and Trotsky were all criticized with varying degrees of venom. Publicizing the document wasn't in anyone's interest."
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Subsets and Splits