[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Why is it an accretion disc and not a spheroid or cloud?

I'd imagine it's the same thing that gives galaxies their shape? I didn't get the opportunity to ask during my intro geology class but it's something I've been wondering for a bit.

[Assistant]
It's all about angular momentum. When you have a cloud of particles, either freestanding or around a stellar body, all the particles are orbiting the center of mass of either the cloud itself or the body. Either way, they're all moving on their own orbits, mostly at random. And when you compound all these movements and orbits, you can calculate the movement of the whole cloud, and it's angular momentum, which is a measure of how much it's spinning.

The cool part about angular momentum is that, unless acted upon by an outside force, it never changes. So what happens is, over time, particles that are moving not on the plane of rotation (the eventual "disc", if you will) will collide with each other and cancel out their perpendicular momentums, but not their rotational ones, and will tend to drift towards the disc plane. Eventually, enough mass accumulates on the disc to start attracting any stray particles and the disc is formed.

I should note that the particles in the disc don't perfectly orbit the center of mass like Earth does around the Sun. Their movement is akin to what the Solar System does around the galactic core, bobbing up and down the disc while rotating around the center.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why do spreadsheet programs like excel and google sheets have the default text wrapping set to 'overflow'? It seems like everyone switches it to "wrap".

Is there some use for excel that's extremely common that I don't know about that uses overflow frequently?

[Assistant] Spreadsheets are made mostly for numbers. Numbers are usually not as long as text so wrapping isn't as likely to happen. Another reason is that reading down a list with uneven row heights isn't as easy and doesn't look as good.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: With variables such as tides and waves, how do scientists measure sea level changes of just millimeters in height?

[Assistant] Hundreds of measurements taken at hundreds of locations, averaged out over time and compensating for seasonal shifts. With all of that taken together, you can get a pretty good estimate of average increases.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Mass Effect] Are Krogan Biologically Mortal?

I can't think of a single historical record of a Krogan dying of natural causes. Even Krogan history points out that before the invention of gunpowder, the main source of mortality was being eaten by predators, and afterwards it became death by gunshot wounds. I've heard of Krogan warlords who were headbutting enemies back when us humans were still headbutting each other over which one of us was more worthy of fighting by Thor's side, and well, most Krogan leave this earthly realm in states decidedly unsuitable for an open-casket funeral.

So, do they ever kick the bucket naturally? Or does their redundant biology and naturally accelerated healing mean that they could technically live forever if they managed not to be eaten, stabbed, shot, lit on fire, used as a living anti-ship torpedo, or in the worst case get in Shepard's way and get eaten by Wrex?

[Assistant]
Yes, they can die naturally. But it almost never happens due to their society and biological predisposition to violence. (A handy survival feature when born on a planet actively trying to kill you, even before nukes turned it into a pule of dusty rubble.) There are most likely records of many millions of Krogan who have lain down and let time take them out, but they rarely share their records with aliens, so you'll never see them. And they're probably not proud of those who do choose to die in such a way, either, which makes them double unwilling to share.

Krogan are estimated to have an average lifespan of about 1500 years, give or take a century or two. Nakmor Drack explains that, at his very advanced age of 1400, he's due to keel over at any time. But unlike humans, who tend toward growing frail and weak, Krogan remain just as strong and hearty as their physical prime right to the end. So it's difficult to really tell exactly *when* a Krogan will actually pass away peacefully.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Given that currents can throw a boat off course, how did submarine navigators know precisely where they were while submerged pre-GPS?

[Assistant]
Compass bearings, knowledge of the currents, and dead reckoning. Prior to nuclear power submarines spent most of their time on the surface because their batteries had very limited endurance. So they could regularly take star sightings and utilize radio navigation beacons.

Modern submarines have very advanced inertial navigation systems, since GPS doesn't work underwater.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Digimon] What makes Veemon have so many potential digievolutions?

Where most Digimon have a rookie, champion, ultimate and mega forms, digi armour and a dna evolution. Veemon doesn't, he has numerous potential evolutions.

Veemon's evolutions include: Veedramon (and his evolutions) and ExVeemon, DigiArmour evolutions including Magnamon. As well as DNA Digivolving into Paildramon and then Impeildramon, why does he have so many potential final forms?

[Assistant] The code that was in charge of making the Royal Knights ran through many generations and settled with having two off shoots of Veemon becoming final members of the Royal Knights. Not all other generations were deleted in the end though allowing the multiple branches of evolution.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Looking for honest advice on recovering from a huge mess up

I graduated with a double-major BA in Linguistics and German from a large T30 state school just before turning 24. I was burning out at the time and dealing with a number of mental health issues + family issues + relationship issues, but I ignored all of that and went on to a MA in Linguistics at a somewhat smaller school.

Unfortunately these issues really caught up with me, and after attending the MA program part-time for 3 semesters, I left with a couple Ws and a couple Fs, just before turning 26. I took a number of graduate level courses during my undergrad, and had done graduate level research during my undergrad. The work of the MA program was not at all a challenge for me, it was just terrible timing in my life and I completely fell apart. In retrospect I should've taken a year or 2 off before attempting the MA, but oh well.

I then spent about 2 years underemployed at a restaurant, seeking much needed treatment for anxiety, depression and ADHD. I left the restaurant halfway into 2020 and went on unemployment voluntarily, because although i did enjoy working in a kitchen, I was only there to stay busy and support myself while I worked out these issues. I did not see it as my career and it wasn't worth it for me to stay during COVID.

I took a bit of a downturn mentally at the beginning of unemployment, but I'm doing much, much better now than I was when I dropped out of the MA program.

Now I have moved across the country to live with my parents (who have finally started to settle down a little), and I am starting a BS in Computer Science in a week or so at a state school. This program should take me about 1.5-2 years because of my previous BA. I'm turning 30 the day before this program starts. My goal is to pursue a MS in either Computer Science or Computational Linguistics, and I still have hopes of following that into a relevant PhD.

My question is, is my previously failed attempt at an MA insurmountable? If I do well in this 2nd BS, will admissions overlook that screwed up MA attempt? I'm also very nervous about my age now, given that I probably wouldn't be able to finish a PhD until I'm 38 or 40 at least. I feel like I'm in a very difficult situation with all of this. I'd really appreciate any general advice or outlooks as well. I know that at the very least, a BS in computer science would help me land a much better job, but my brain still won't stop pushing me towards an academic career.

[Assistant] Don't take life too seriously. Pursue what you feel love for and screw everything else. Don't do stuff to get "a better job", do it to have fun, meet people and make memories. A failed rocket scientist is closer to becoming a successful one than someone just thinking of becoming one. You have academic experience under your belt, leverage that to accomplish your goals. Failure points you in the direction of success. Experiment, fail, repeat while taking into consideration the data you've gathered in the previous attempt!


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Spider-Man] Spider-Man's radioactive blood was able to cure him of vampirism in mere hours - but at the same time he's had colds and flus that have lasted for days. Does this mean the colds and flus are stronger?

[Assistant]
What it likely means is that the biological base for vampirism is much more complex than a virus. Viruses are very resistant to radiation because they are small and very simple.

See, radiation damages cells when a particle of radiation happens to impact part of the genetic code. Viruses are small and simple enough, and have little redundant bits of code, that they don't get hit often, and when they do it often doesn't destroy them.

Large, complex cells, like bacteria, or whatever transmits vampirism, will get hit much more often, and an error in their code  can be much worse because of all the processes that interact and depend on each other.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Wars] What are the benefits for working for the Empire?

I am just an orphan who wants to work but no one will hire me so I want to work for the Empire as a stormtrooper. I am 20 and in good health but before I do what do I get out of it?

[Assistant]
They feed you, house you, and pay you.

If you're more ambitious, a military career is an essential element to advancing through Imperial politics. The odds might be against you, but theoretically anyone could rise through the ranks. You may very well have your own star-system some day.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] When it rains on the ocean, does the fresh rainwater harm the marine plankton? If not, why not?

[Assistant] There is so much salt water in the ocean that rain doesnt even begin to dilute it to harmful levels. In estuaries where rivers meet the ocean there is whole environment that is a different biome from the rivers and oceans with brackish plants and fish and everything.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Government Spending is Being Blamed for Inflation - How Exactly has Recent Government Spending Contributed to Inflation?

[Assistant] Most of the analyses Ive seen put government stimulus at around 10% to 50% of the peak inflation weve seen. This is balanced with similar analyses that credit government stimulus with a very quick recovery and millions of jobs created/poverty avoided. This is referring to the US at least.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: How is low rep strength training different from higher rep size training? How do the muscle fiber grow differently to accomplish this?

[Assistant]
Muscles work by snapping some muscle fibers under whatever stress you are putting them to, then replacing them with more fibers. This allows them to match whatever your needs are using only simple rules, a common theme across all of biology. While strength training, you're focused on the healing part more: you want more muscle fibers in exactly the places you need to strengthen the muscles you are training. Therefore, you do some reps to break a few fibers and then them heal up, making sure your body's systems can keep up with the healing.

In mass training, you're trying to make your body massively overcompensate by breaking tons of fibers with long strings of reps, leaving little time for the healing process to begin. By breaking everything at once, the body rushes in to repair the damage, going overboard in the process so less damage is done the next time you do that. In addition, that many reps quickly runs your muscles out of oxygen, forcing those cells to begin building up lactic acid and burn through their sugar supplies very quickly. The lactic acid also damages cells and sends signals to the surrounding tissue which encourage vascularization, the growing of new blood vessels and widening of existing ones. The increased blood flow also helps bulk up a bit just due to there being a lot more fluid in the area now, and also creates the huge, prominent veins you see in bodybuilders.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Samurai Jack] Why did none of the aliens Jack helped come back to liberate earth from Aku?

In the old videologs and records of the time, it is clear that Jack helped at least one powerful alien species (the wasp people), and possibly several others with advanced technology. Why did none of them return to earth to liberate us from Aku?

[Assistant] Because their conventional weapons don't really work against Aku. For example, when Jack visits Atlantis and those creatures try to fight back against Aku, their weapons are basically powerless; their arrows go straight through him. Only Jack's magic sword works.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Whenever you look at any light source, lines or streaks protrude from them. Why is that?

[Assistant]
Someone else already answered why this happens with camera and telescope lenses.  If youre using just your eyes, its not supposed to happen (but often does).

Its caused by small imperfections in the cornea and/or lens in your eyes.  If its bad (ex. it makes driving at night difficult), see your eye doctor.  Its likely a sign of astigmatism.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
How long is the Vagus nerve?

How long is the vagus nerve, end to end? Not counting branches (or is someone actually approximated that, awesome.)

I tried finding an answer and failed!

[Assistant] Vagus' nuclei are in the medulla oblongata, which is inside your skull, towards its base. The lower-most fibers innervate the small intestine, which runs below your belly button. If you touch the base of your skull with one hand and your pubic symphysis (the bony bump below your belly and above your genitals) with the other hand, that's close to the length of the vagus nerve.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
If transcription and translation are coupled in prokaryotes, how do mRNA quantification methods provide meaningful results?

Wouldn't it be more of a measure of the brief latency between transcription and translation than an indicator of transcript or protein level?

[Assistant] Huh? It's not like the mRNA gets destroyed during translation. It's just a measure of how much RNA is present. It's true that it may not give you a good idea of how much protein is there, but that's the nature of the method.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5:The American civil war

As a European, this war is something I've never understood but I feel like I probably should by now.. Can someone help me out please?

[Assistant]
American politics from the late 1820s until 1860 were focused primarily on slavery.  The "free states" in the North jockeyed politically with the "slave states" in the South for power.  There were a number of crises and a number of compromises.  In the 1850s tensions rose as the USA expanded westward across the continent: would the new territories allow slavery, or not?  Blood was spilled.

In 1860, Abraham Lincoln was elected President of the USA as a member of the newly-formed Republican Party, an explicitly anti-slavery party.  Lincoln had not even been on the ballot in some Southern states, but because of the greater population of the North and the way the election worked out, he won without getting a single electoral vote from the South.

In 1860 and early 1861, fearing that the new President would take their slaves away, Southern states began seceding from the USA.  They formed themselves into the Confederate States of America.  Lincoln refused to recognize them as a sovereign nation.  In April 1861 they attacked a US Army fort, Fort Sumter, in the southern state of South Carolina.  Thus began the war.

The North's strategy was devised early in the war, and never much changed.  It was a four-point plan:
1) Use the North's navy to blockade all Southern ports (the South had no Navy to speak of)
2) Capture the Confederate capital of Richmond, Virginia, which was only 100 miles from Washington DC
3) Use combined land and naval forces to take control of the Mississippi River, cutting the CSA into two
4) Invade the CSA's heartland

The South's strategy was to defend themselves until the North decided that fighting them was not worth it anymore.  They also hoped for foreign intervention from Britain, France, or Russia.

In 1861 the war was mostly minor and stalemated.  The naval blockade (Union point 1) went into effect.  But in the East an attempt to take Richmond (point 2) was repulsed.  In the West, the North succesfully persuaded the states of Missouri and Kentucky to not secede.  Confederate displays of strength dissuaded them from moving farther South.

In 1862 the conflict really erupted.  The naval blockade continued.  In the East, Southern forces repelled two more attempts to take Richmond, invaded the Northern state of Maryland themselves but were defeated, then repelled another assault.  In the West, Union forces pushed south through Tennessee and into Mississippi, and repelled a Southern invasion of Kentucky.  On the Mississippi, Northern forces pushed southward.  A combined-arms force from the Gulf of Mexico captured New Orleans at the mouth of the river and began pushing northward.  By the end of the year the North controlled nearly all of the river.  Only the fortress town of Vicksburg, Mississippi held a bend in the river, preventing total Union control.

1862 saw the first *real* Civil War battles, and all pretense of a quick or bloodless war was gone.  Modern technology and outdated battlefield tactics meant that these battles were slaughters.  Each battle saw losses comparable to England's at Waterloo.  But where Waterloo had been a decisive battle, these battles happened again and again.  The dead began to pile up.

In 1863, the tide truly turned against the South.  The naval blockade continued.  In the East, Southern forces repelled another assault on Richmond, then tried invading the North again.  They were decisively defeated at the Battle of Gettysburg, and they started to no longer be able to replace their losses.  On the Mississippi, Vicksburg fell.  This put the entire river in Union hands, accomplishing Point 3 of the Union strategic plan.  The CSA was cut in two, and Union river traffic could proceed down to the Gulf of Mexico.  The army that took Vicksburg was free to turn to the Western Front, combining with the armies there and forcing the Southern forces back into Georgia.

After 1863's prominent victories, people thought the end of the war was near.  It was not.  1864 was a bloody mess as Union forces marched onward.  The naval blockade continued.  In the East, Southern forces fought off another assault on Richmond.  But instead of retreating as they had after previous defeats, the Northern army simply repositioned and struck again.  Stalled again, they repositioned and struck again.  And again.  And again.  Each time, they pushed a little closer to Richmond, until finally they had the Southern army caught in a siege.  The two armies would remain there, bleeding each other dry in proto-WWI trench warfare, for nine months.

In the West, Union forces maneuvered their way into Georgia, forcing the Southern army constantly backwards.  They took Atlanta, but allowed the army to escape.  Attempting to pull the Northern army back north out of Georgia, the Southern forces drove northward back into Tennessee.  The Union forces split in two.  Half pursued the Southern troops, and decisively defeated them by year's end, destroying the last serious Southern fighting force (that wasn't holed up in the siege in the East).  The other half of the Union army headed eastward from Atlanta.  With no army to oppose them, they burned their way across the land, destroying farms and railroads.  By year's end they had reached the Atlantic Ocean, a trail of scorched earth behind them.  Point 4 of the Union strategy had been accomplished.

By 1865 the war's outcome was clear to all.  But that didn't stop the South from fighting on.  The naval blockade continued.  In the East, the siege continued.  Confederate troop replacements and supplies were running dry.  On the "Western" Front (now more South than West), the Union forces turned northward, and began burning their way through South Carolina as they had done to Georgia.  Their goal was to meet up with the forces besieging the last remaining Confederate army, and crush them with overwhelming force.  But that wouldn't be needed.  The Union forces finally broke through the fraying Southern lines after nine months of siege.  The Southern army was forced to retreat into the Virginia countryside, abandoning Richmond.  Union troops took the city, finally accomplishing point 2 of the Union strategy.  They pursued the retreating Southerners and surrounded them.  The last Confederate forces surrendered, in April 1865, after four years of terrible, bloody war.

President Lincoln lived just long enough to see the first of the major surrenders on April 9, 1865.  Five days later, he was shot and killed by an assassin.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Scheduled C-section - how does the body know its no longer pregnant?

 Pretty straightforward question - how does the body know it's not pregnant after a scheduled C-section?

I'm guessing when it goes through labor for a vaginal delivery the body is preparing to not be pregnant any longer, but how does it know when there is no labor involved? After the C-section is it just like "oh, no baby here, guess we're done."?

Thanks!

[Assistant] The placenta secretes a ton of hormones. One of the critically important steps in a C-section is for the surgeon to go over the uterus and make sure that every bit of the placenta is removed, and scrape off anything that isn't. Even small bits of placenta can cause serious complications, like heavy bleeding. As a medical condition this is called "retained placenta" and can happen after C-sections, vaginal delivery, miscarriages, or abortions. In some cases a complete hysterectomy may be required to treat.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Zombieland] where the Hell did Columbus get a rifle?

In Zombieland, Columbus tells us his backstory about how he is a reclusive, somewhat cowardly, college student. 2 months into the apocalypse, he has a rifle and he is a pretty good shot. Like a really good shot. I know the answer could be simple- he got one after the inevitable riots occurred and the gun stores were left abandoned. But in that time, it seems unlikely he could survive even a week without that sort of protection. Seeing as he was on college, which is doubtful to let students carry rifles on campus, he was a cowardly recluse, and he couldn't have known about the apocalypse occurring, how did he get a rifle and where the hell did he learn to shoot?

[Assistant]
Making some broad assumptions about his capabilities and location. He probably holed up in his dorm as long as possible during the beginning of the outbreak. Surving the initial hordes subsisting off of ramen and frozen dinners from the other dorms or apartments around. Using stairwells and simple barricades to keep the slow clumsy rotters out. He then used his skills as an avid gamer using lightguns and wii remotes with a target shooting rifle collected from the campus locker room. It's not a powerful gun but enough to kill a zed with an accurate shot. He then ventured out for food and supplies finding a better rifle and ammunition among the dead or in an abandoned big box store like Walmart.

Or alternatively he had an upbringing that included training with firearms as many American children from rural areas often do. He collected the rifle from somewhere else but already had skills prior to the apocalypse.

And the third more worrisome option is he was prepared for the apocalypse. Either through LAARP or simple fantasy play he imagined an apocalypse and wrote up the rules for zombie survival beforehand. He is reasonable in shape and knowledgeable despite his unassuming nature. He could have simply been someone that trains for the apocalypse as a joke or for fun and suddenly found himself in a real apocalypse where it came in hand. Sort of like those doomsday preppers but actually effective instead of just planning different murder devices and thinking MREs have an unlimited shelf life.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Why does clear phone cases turn yellowish over time?

[Assistant]
Think of the material as being made of long strings. Something like a bug screen on a window, in fact a whole bunch of those screens stacked up so the holes match up perfectly and light can keep passing through.

Over time the environment (mostly UV light) breaks some of those strings down. As they break into smaller units, the various twists and snags start to block some of the grid of openings, so instead of all the light passing straight through some of it is blocked and reflected back as that yellowish color.

We're talking about polymers breaking down, here, but maybe that visual makes sense? Polymers are long strings of molecules arranged just so into a material. As they break down into smaller, more randomly arranged strings their appearance changes and they can go through physical property changes like becoming brittle, depending on the exact material on question. As the structure breaks down, other additives can also leak into bits of the structure it wasn't meant to be in and colors it, too.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Pokmon] Isn't Brock a little weak to be a Gym Leader?

What happens when a kid who grew up in Fuchsia comes along, who had to train to beat Sabrina first? Do the gym leaders have teams of strength appropriate pokmon for different challengers? Or does the Gym challenge HAVE to be done in a specific order?

[Assistant]
Per the Pokemon Trainers Handbook:

Regulation 10.5.9 Gym Leaders and their teams.

Each gym leader is to possess a number and variety of Pokemon for use in duels against opposing trainers. Any gym leader not possessing at least six Pokemon of varying skills will face expulsion of forfeiture of their gyms and gym leader status. It is the duty of the gym leader to properly train any and all Pokemon in order to be a challenge to trainers of varying levels and abilities.

Each Pokemon must be of varying levels and abilities, from beginning Pokemon to experienced battlers per Regulation 6.8.2 "Gym Leader Certification" in order to best challenge the hopeful trainer. Any gym leader found to abuse or neglect this rule will be sent before the Pokemon World Training Authority and will face sanctions not limited to expulsion and forfeiture of his gym leader status and gym.

It is the duty of the trainer to notify all gym leaders of how many badges they have received, and how many Pokemon they possess. Failure to do so may result in forfeiture of any and all badges per the gym leaders discretion. Any failure to do so may also result in the gym leader utilizing his or her strongest Pokemon for use in the duel. Failure of notification will result in a "Duel Regiment", and allows the gym leader to determine any and all regulations to the battle.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Beauty and the Beast] Which war did Gaston fight in?

[Assistant] Potentially the War of Austrian Succession, a global conflict that lasted 8 years, from 1740 to 1748, and involved nearly all major powers in Europe as well as their colonies. A subset of the fighting between the British and the Spanish in the Caribbean was known as the War of Jenkins's Ear.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Star Wars] How are trade routes taxed/tracked? Everyone just seems to jump into hyperspace without regulation.

[Assistant]
Id assume like they are now. Goods are marked from point of origin amd taxed by the planet you land on.

Hyperspace routes are likely taken from the nav computer and a tax for use is likely given to the discoveror for the first 20 years or so.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: why can't we just take the carcinogens out of cigarettes to make them safe?

[Assistant] Some of the things that are bad/dangerous about cigarettes come from combustion (burning) that is part of smoking. Even if you removed any kind of chemical additives and just smoked tobacco, youd still be inhaling the products of combustion, which are not good for your lungs.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Do spiders scout out multiple places before deciding to spin their web and if so, are environmental conditions taken into account (wind speed, temperature, humidity, etc.)?

[Assistant]
A lot of spiders spin test webs, just a few strings in several locations and check on them later to see which one roughed it out better.

Now, spiders have several sensory organs that determine a location's appropriateness based on humidity, heat, cold, wind, light, etc., but sometimes a spot is just not good for non-environmental reasons. So many spiders set up individual strings here and there, and the one that lasts the longest or remains intact the most will later be used.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: How do the results differ between a workout of 100 pushups straight vs. 100 pushups throughout the day?

[Assistant]
100 pushups straight (or however many your body can handle) rips your muscles up. This way your body knows to repair itself stronger than before so it doesnt rip itself up again.

100 pushups throughout the day gives your body enough time to recover between the sets and thus not ripping up as much (or at all if your body can handle it).


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Free Fallin'] Why are all the vampires in Los Angeles traveling west on Ventura Boulevard?

[Assistant] The sun rises in the east and sets in the west; Ventura Boulevard is a major east-west thoroughfare. As the sun is setting, the eastern side of the street gets darker first, with deeper shadows to hide in. Thus, "the vampires traveling west" on Ventura Boulevard suggests that the sun is setting, and they are able to move more freely as the shadows move westward. The many shopping locations along Ventura Blvd., such as Studio City, make this a prime feeding ground for younger vampires that require nightly hunting to maintain their undead existence, but cannot afford to live south of Ventura, and so have to make the trek every night.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Why can we talk in our heads?

Hey guys, I've always wondered how we are able to talk in our heads. I can say a whole sentence in my head and when I think about that it seems crazy that we can do that. So how are we able to speak in our head without saying it?

[Assistant]
Language related information in the brain is represented at different levels of abstraction. At one end of the spectrum you have the basic visual and/or auditory input coming in from our sensory organs. This information must be preprocessed and analyzed by sensory cortex to reach the point at which we represent it as an actual word form. At the next level, word forms are represented amodally (i.e. equivalently across sensory modalities) and are linked to their grammatical properties. Finally you reach the other end of the spectrum of abstraction where words are linked to their semantic content.

In language production this process is essentially reversed, the primary difference being the fact that the lowest level of abstraction is motor programming of the mouth and throat rather than input from the eyes and ears. Inner speech essentially just stops short of this lowest level - auditory word forms and their grammar are represented, but we don't actually send the necessary information to enunciate them.

It's worth pointing out that not all of our thoughts - even complex, abstract ones - are "spoken" to ourselves in this way. Mental imagery is a good counterexample.

As to why, in an ultimate sense, we have/make use of this ability: from an evolutionary perspective it may simply be a spillover benefit from language (which of course is hugely adaptive for us). However, given the role of language in enhancing working memory via the phonological loop, it may also give us the capacity to think about more at the same time.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Which is better, a 90% chance that you get $1, or a 50% chance that you get $2? (This chance is occuring every second)

Im just curious for the game Im playing, this has no real scholarly or practical application.

Also assume no inflation or anything like that, its just a game lol.

[Assistant]
To solve this question, you have to solve for the EV (Expected Value).

EV = (Value of prize \* probability of winning) - cost of entry

Assuming you don't have to pay to play this game, cost of entry is 0.

EV = $1 \* .9 = 90 cents

EV = $2 \* .5 = $1

Clearly, the second choice is better, because you earn an expected value of $1 per trial.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why can't they make CPUs bigger if heat dissipation is a problem?

If heat is distributed through larger area/volume it will be easier to dissipate, no?

[Assistant]
It's a bit unintuitive, but that's not exactly how it ends up working.

A more densely packed, smaller CPU design made out of smaller individual transistors is actually more power efficient. It suffers less electrical losses, and so it generates less heat. The performance and efficiency benefits to going smaller generally far outweigh any consequent heat dissipation issues that might be caused by the increased density. Removing heat from the die isn't that big a problem anyway.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
What inspiration did early christianity have from greek philosophy?

I heard they took some ideas from stoicism and platonism. And apparently aristotle's metaphysics?

[Assistant]
There was an important social and cultural shift that occurred in the Roman empire during the third century.  Prior to this shift, Stoicism was more or less dominant in the philosophical culture of the empire, whereas after this shift, neo-Platonism became dominant.  Christian writings from this period often show significant debts to the dominant philosophical culture of their time, so that the earlier Christian writings often show the influence of Stoicism, while those after the third century often show the influence of neo-Platonism.

Aristotelian metaphysics was a significant influence on neo-Platonism, which was not just a return to Plato but also to a considerable extent a syncretic reflection on the Greek philosophical tradition broadly, so that the early Christians received their Aristotle through the broad tradition of late antique Platonism, which included Aristotle as the second great thinker of the Greek classical period.  But often when people speak about Aristotle's influence on Latin Christianity, they have in mind the particular influence that becomes prominent in the 13th century, much later than the period of early Christianity, following the Latin reception of Islamic Peripateticism.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
How do people find time to work on multiple research projects and publish multiple papers? I can barely find the mental capacity for one.

I'm an MSCS student who does research in machine learning. I've noticed that many people work on several projects at once (usually their own project and as a participant in another) and often have multiple papers published in venues.

Right now I'm trying to get my own research project going as I'm graduating next semester and need to write my thesis anyway, and am also involved in another project with a PhD student at my lab.

I find myself usually spending 100% of my time on this project, and my colleague seems to expect that as well. I spend the entire day at the lab working on that project, and at night I'm also constantly wondering what kind of ideas I could try out.

I've tried doing the "alternate days" thing, but I find that it often takes me more than a day to work on some ideas, and when I'm done with that there are more things to do for one project.

Maybe my predicament is the result of me being relatively junior and not trained enough, but if there are any tips that you guys could give me that'd be great. The most advice I get from my lab mates and advisor is along the lines of "everyone goes through it."

Thanks.

[Assistant] It just comes with experience. Time management is critical, too. Once your own project is up and running, youll hit points where theres nothing to do but sit and wait for data, IRBs, reviewers, finding, etc. Those are the gaps you fill with other projects. Plus youll gain enough expertise to serve in more of a consulting role which doesnt take as much time as running a project by yourself.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Trek] Can The Borg adapt to high speed projectiles such as a bullet?

In the movie First Contact, Picard uses a Tommy Gun to kill some Borg saying that even a holographic bullet can kill.  Can the Borg adapt to a high speed projectile?  If not, why don't they just replicate some AR-15s and clean them up pretty quick.  Also could that be effective again their ships?

[Assistant]
The Borg are certainly capable of adapting their shielding to project a standard force field, which is all that would be necessary to stop a simple kinetic energy-based projectile weapon. While Capt. Picard was able to use an ancient-model weapon effectively, the Borg were unprepared for it, and he did only use it on two drones. No doubt after those drones were killed, the others adapted their shielding to be prepared for that kind of an attack.

The basic point is this: the Borg adapt, and are incredibly versatile. An unconventional attack can damage them, but they will adapt their defenses quickly to account for any new tactic. Especially when the tactic could be as easily neutralized as a bullet.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Wars] Why are IG units not used in war?

Weve seen their (or at least one) fighting capabilities in The Mandalorian, so why not deploy them in general combat like during the clone wars? Is it just theyre too expensive? Or is it some other reason?

[Assistant] I think they're too independent for war; IIRC they rebelled against their creators and went off taking jobs for themselves so they probably wouldn't make good soldiers. But good bounty hunters and assassins, for sure.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why do girls, with virtually no boobs, wear bras?

Hi!

Just thought if this as I, in my hallway, looked at my magnificent semi-fatguy-goes-bodybuilding-body; I've got bigger boobs than my ex-gf and my current.
Both of them uses bras, but I don't. I don't see why I should wear one. They, on the other hand, who are as good as completely flat with the bras off, uses them.
There's nothing to support, really, so that one reason probably goes away.

So, why is this? Marketing? Habit? Because girls are supposed to wear them? Trying to make the boobs look bigger like some Spinal Tap-stuffing-thingie?

I don't want to ask my gf, because I don't want her to think that I don't like the way she looks :)

TL;DR Why do girls without boobs wear bras when there are nothing to really lift/support/whatever?

[Assistant]
Firstly, there is often more breast tissue than is immediately apparent. For wide-rooted breasts, a significant portion of breast tissue can lie around the underarm area. So don't underestimate the mass of boob just because they don't stick out much at the front!

A well-fitted bra will support all the tissue and cup it so that the stuff which tends to lie at the sides is comfortably moved to create fuller breasts and more cleavage.

Breast tissue can also be very uncomfortable when moving quickly, especially when jogging. Imagine wearing a hoodie, with something heavy in the pocket on the front. You know the way it bounces around when you run? That's how boobs feel, even small ones, and it can be painful! The right bra eliminates that.

They can also protect sore breasts and nipples from rubbing, smooth outlines under clothing, and make you feel good about your body.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
GPS satellites work because they adjust for similar bending of spacetime to coordinate with systems on Earth. Why wouldn't they?

What possible errors could they make without this adjustment? I thought all they do is to point us direction or pinpoint our location. Why are they really concerned about time?

[Assistant]
GPS satellites need to know the time.

They don't know what direction you are in, and even if they did the error would be humongous. It would be very tricky to make a satellite system that could accurately pinpoint a transmitter in this way.

The way it works is GPS satellites continually transmit both the current time according to their onboard clocks and their current position, which is known very accurately. At a given time your receiver will simultaneously get this information from a handful of different satellites (I believe 4 at minimum should be necessary) . The time data won't be precisely the same since the different satellites are different distances from you.

If, for example, satellite A time is 1 second earlier than satellite B then you know that satellite A is 1 lightsecond farther away from you that satellite B. You use the data from several satellites to work out the relative distances to them from you and, since you know where each of them are, you can finally compute your location (and the time at your location actually).

The reason they need to adjust for relativity is that both the speed they are moving at (relative to the surface of the Earth) and the gravitational field they are in (relative to the surface of the Earth) effects how the onboard clocks tick relative to each other.

If the time on board each satellite does not precisely match each other then you will not be able to work out the time of flight of the signals and you cannot then work out the relative distances to the satellite. This would ruin the ability of GPS to function.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: A single tree might shed thousands of seeds a year, but most of these won't grow into anything. What starts the growth of a mighty tree?

[Assistant] If you look closely, many trees are surrounded by saplings. Most wont make it to maturity because there isnt enough sunlight reaching them under the canopy of large trees. Sometimes, an old tree will die, allowing some saplings to grow until they become mighty and take the place of the dead tree. This type of growth from death happens in many ways. For example, some pine cones only open up when they get extremely hot during a forest fire. The fire revitalizes the nutrients in the soil and opens up the canopy, allowing light to reach the ground and new trees to grow.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: what causes halucinations in your brain when you take LSD and how do they differ from hallucinations that someone with schizophrenia would have?

[Assistant]
Technically what you see when you take LSD isn't a hallucination, it's a pseudohallucination. The difference is that people on LSD recognize that what they're seeing isn't real, but people with schizophrenia don't.

The visual effects of LSD have to do with it interacting with serotonin receptors that control vision. The mechanism isn't well understood.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Is there a way for us to know what the population of any given species of dinosaur was during their time on earth? And if so, how?

[Assistant]
Certainly not.  In a field where we aren't sure what are separate species, there is little chance of being able to make such precise observations.

We can estimate that X dinosaur was more numerous than Y dinosaur for a given period, but anything more would be too poorly supported.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Star Trek] What kind of water comes from the replicators?

I know you can program different recipes into the replicator, but what is dispensed when someone orders water? Specifically, is it just H2O, or are there other chemicals like we would see in city/tap water? I imagine specialty items like Spring Water or Mineral Water would have their own formulas programmed.

[Assistant]
It's probably "just" water, with only the minerals and such that can be tolerated by all (or at least the majority) of Federation citizens.

Of course, it's also possible that the replicator knows who's asking, and gives them a glass of whatever they'd get from a very clean river on their homeworld.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Star Wars] What are the chances a planet which strikingly resembles 21st Century Earth in terms of culture, technology and geological diversity exists in the galaxy?

[Assistant]
Geologically? There are plenty of diverse planets around the GFFA.

Culturally? Most planets aren't as diverse as ours, but the galactic culture itself is hugely diverse.

Technologically? Essentially nonzero. You have to remember that galactic society has existed to some degree or another for at least twenty-five thousand years. The chances of a planet being left behind technologically, barring it being some weird cultist shithole in Wild Space or the Unknown Regions, are practically nonexistent.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Cars, solariums, and greenhouses can get really hot because they trap heat coming in through the glass. Why can't the heat leave just as easily? Why doesn't it balance out?

[Assistant]
The energy comes in as light and doesn't turn into heat until it gets absorbed onto the interior surfaces. Then the heated materials and air inside do not leave the car while continuing to accumulate more heat.

Some heat is always leaving the car but until the sun goes down there will be more heat coming in than is leaving.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Dragonball] Why do the androids seem to go in reverse order of power?

Note that I understand this isn't strictly true: Androids in the original Red Ribbon Army (that Terminator-looking one, and Android 8) are almost certainly weaker than most other forms we've seen. Also i'm discounting Cell and 21, even if they are technically Androids.

That said, starting with Android 13 we see the strongest regular android, followed by 14 and 15, 16 seems to possess a lot of raw power but be unrefined, and 17 and 18 seem to be below him since they couldn't really do much to Cell to begin with, or so it seemed.

Also 19 and 20... exist. Briefly. And get utterly wrecked by Super Vegeta, who is then trashed by 18.

[Assistant]
I don't know where you got the idea that 14 and 15 are stronger than 16, 17, 18, or even 19 and 20.

14 and 15 manage to give some trouble to the Saiyans, but only in their base forms. When they go Super Saiyan, the androids get demolished almost instantly, putting them around the league of 19 and 20.

As for 13, he's only particularly powerful when he absorbs components from 14 and 15, in a manner similar to Cell absorbing parts from 17 and 18. Before that, 13 is shown to be able to keep up with a Super Saiyan, but not easily overpower it like 17 and 18 could.

It's not specifically stated why 19 and 20 are weaker than all of the others (ignoring the terminator-like one and 8), but I'd hazard a guess that it's because Gero decided that absorbing energy was more useful than infinite energy (he clearly turned out to be wrong).

<Doylist>
(By the way, in Daizenshuu, Akira Toriyama states that #16 is more powerful than #13.)
</Doylist>


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
CMV: When rehabilitation is not an option for a prisoner i.e. those on life sentences, the prisoner should have the option of completing his sentence or state assisted suicide.

I feel as though debates on the death penalty vs life sentences are very tricky. Life sentences are often criticized for costing too much money. The death penalty is often criticized for being barbaric and inhumane. I feel as though the best approach to the problem is through a compromise in which the prisoner chooses the method of his punishment. I feel as though this compromise is the most humane among the two previously debated options. Some prisoners would value their life and take life in prison as they fear death. Some prisoners would take death as they don't want to live the rest of their lives in a prison. Rehabilitation should be the number priority, and when one cannot be rehabilitated I think the second most important thing is that the person be removed from society in the most humane way possible. Giving the option of life or death is much more humane than either giving them life with no choice or death with no choice. I also believe that if this were to be implemented that it should only be an option to those on life sentences not to your ordinary prisoner. It would also likely decrease the amount of money spent on life sentences as some prisoners would take the option of assisted suicide. Tell me why this wouldn't be a great idea.

[Assistant] A life sentence isnt about just dying in prison. Its about spending the rest of your life, however long it is paying for your crimes. Letting people commit suicide is a cop out. And to be perfectly honest, they can just do that anyway.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: What exactly was the danger of the Y2K bug - what are the consequences of a computer recognizing '2000' as '1900'?

[Assistant]
The consequences are that a calculation involving the difference between two dates suddenly returns nonsense values.

Imagine you're running a system that pays a pension for people aged 65 or over. Someone born in 1930 might have been quite happily claiming their pension as a 69 year old in 1999, but in 2000 the computer would think that they weren't even going to be born for another 30 years!


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Brainfreeze

Whenever I get brainfreeze, I was always taught to put your thumb on the roof of your mouth. Is there any actual "science" behind this? Is it really a tiny transfer of body heat that makes the brainfreeze go away, or is your brain just distracted by something so obsurd that it "forgets" about the brainfreeze?

[Assistant]
There is some evidence for it, but pressing your tongue flat against the roof of your mouth works better.

Brainfreeze happens when your body goes OH SHIT THATS TOO MUCH COLD RIGHT NEXT TO MY BRAIN! So it opens up all the blood vessels trying to warm it up, and that's what caused the pain. Warming it up will shrink the blood vessels back down, no more pain.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: why do images of things on a microscopic level not have color?

[Assistant] You are probably referring to electron microscope images which are taken with electron bombardment rather that visible light; indeed some of the structures may be too small to image with visible light because the wavelength is too large. Under such circumstances there is no color in the resulting image because color has no meaning.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
What is holding us back in making more efficient batteries, to store e.g. solar generated electricity?

I'm reading a lot of places that what really hinders renewable energy sources from reaching its peak is that we're unable to store energy properly. Could someone elaborate a bit on that?

Secondly, given that the statement is true, why can't we use rechargeable batteries, e.g. lithium batteries, to store the energy produced? Wouldn't a solution to this make solar power a lot more attractive than what it already is, since you would be able to store daytime generated electricity?

[Assistant]
We are using batteries to store excess renewable energy.  Just not the kind of battery you're familiar with.  There's something called a flow battery, explicitly designed for grid-scale energy storage.   Many companies are racing to commercialize their products to handle the burgeoning demand for renewable storage, using many different chemistries that are quite different from consumer batteries.  The main idea of a flow battery is to decouple energy and power.  Power is the instantaneous voltage times current, while energy is power over a duration of time.  A lithium ion battery has a fixed relationship due to the need for the lithium ions to be within a certain distance of the electrodes.  This means in order to increase capacity, you have to increase everything that goes into the battery as well.  A flow battery uses external storage tanks of electrolyte that can be of arbitrary size that is independent of the electrode area.  The electrode area determines the power, but the size of the tanks determine the total energy capacity.  Need more capacity?  Just add more tanks.

This tech has its own set of challenges, however, and they're not trivial.  The main problems stem from electrolyte crossover through the separator membrane,  efficiency degradation, and cost of the electrolyte.  There are literally dozens of different chemical schemes being explored right now with the aim of addressing these points.  Bets are on as to which tech will win out.  Chances are, however, you the end user will never purchase such a system.  They're designed for utilities to incorporate.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Was anyone outraged at Plato's writings about Socrates?

Socrates was executed by the Athenian Assembly, after all, for such things as corrupting the youth and strengthening weaker arguments. I would imagine any supporter of his would sense some danger in continuing his philosophic thought. My question is when Plato began to write about his former master, did anyone object to his sympathetic portrayal? Was Plato initially disgraced or criticized?

[Assistant]
Plato was a part of the problem for Socrates, because of his family links to Charmides (his uncle) and Critias (his mother's uncle), members of the Thirty Tyrants who ruled Athens for a period after they lost the Peloponnesian War. Critias had himself been a student of Socrates'. The Thirty Tyrants oversaw large amounts of executions and the seizure of property of people they thought hostile to the state, leading to the death of as much as 5% of the Athenian population. By this token Athenians were *very* hostile to the Thirty Tyrants and their associates, which included Socrates by way of his association with Critias and Critias's family member Plato.

Socrates's association with the disgraced public figure Alcibiades didn't help either.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5:What does "/16 or /24" after an IP Address mean?

Hello all - I have seen the /16, /24, etc multiple times after an IP Address and I just don't understand it!  How do I know which number after the slash belongs to my home network?  Any help/guidance an explaining this would be very much appreciate!

Thanks in advance!

EDIT 1:  Thank you everyone who replied and for not making me feel so dumb! haha  I now have a much better understanding of what this means! :)

[Assistant]
It is a decimal representation of your subnet mask.

Your computer has an IP address. Something like:

    10.1.1.2

But this address represents two things: a) your computer; and b) the local network your computer is on. And it needs a way of knowing which part is which.^* To do this it uses what is known as a subnet mask which can be represented in a number of ways. The "slash" notation, followed by a number, is how many 1 bits are in the subnet mask, in the case of /24, that would be 24 1 bits.

Remember that computers deal in binary, so...

    10.1.1.2

Is actually:

    00001010.00000001.00000001.00000010

A subnet mask of 24 would be:

    11111111.11111111.11111111.00000000

Each bit of the IP address that lines up with a 1 bit in the mask is part of the network (in this case 10.1.1.x). Each bit of the IP address that lines up with a 0 bit in the mask is a host address (in this case x.x.x.2).

Your computer uses this information to determine if communication is destined for the local network (and doesn't need to go through a gateway) or is destined for a remote network (and does).

In this case, everything from 10.1.1.1 to 10.1.1.254 would be considered local. All other IP addresses would be remote.

\* - Originally, they designed a scheme where IP addresses would fall into certain classes that defined which part was the network part and which part was the host part. For example, if it began with a 10, then the first octet was automatically the network part and the last three would be the host part. This turned out to be insufficient for modern networking needs, so they developed the concept of subnetworking of which the subnet(work) mask allows us to chop up the address any way we want.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5 why do smart phones shut off in cold weather before theyve reached 0% battery?

Recently Ive been out in the cold and my iPhone has shut off with about 40% battery remaining. Is this a simple answer such as its too cold for electrons to flow in the battery?

[Assistant]
I'll provide a brief answer.

Phones today are powered by lithium-ion batteries. They rely on the flow of ions (something like electrons, except bigger, slower) through an oily-gel like material (makes them even slower!) across two 'plates' as they discharge to power the phone.

When it gets cold, it gets harder to move (just as you'd find it harder to move in the cold) and after a certain threshold, the battery just seizes up and ions just don't move fast enough to provide enough current for the phone. The phone shuts down.

This threshold temperature is rather cold, in the -30 ~ -40 C. but depending on the battery, conditions that you were out in, initial conditions and whatnot, you may see it shut off at relatively warmer (~ -20 C) temperatures as well.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5 Why did thatched roofs not rot and collapse from the rain and damp? Or if they did rot, how frequently were they replaced?

[Assistant] They did rot, but because of how they are layered on the roof, it sheds water pretty efficiently (that's how they didn't rot quickly, water shedding ability and tight layering protecting lower layers) and a well thatched roof in modern times can last 50 years before it's beyond use. Historically, at least in parts of England, a new layer of thatch was added to the aging/weathered layer and some houses have been found to have seven feet of thatch on them with the oldest layers being 500 years old.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] In a Meson, why do the quark anti-quark pair not just annihilate each other ?

[Assistant]
Some mesons can and do annihilate. The neutral pion pretty much always decays to two photons, for example.

However, not all of them are quark-antiquark pairs of the same type. Charged and flavoured mesons have valence quarks of different types, such as kaons, D-mesons and B-mesons. This means they decay via other processes.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Why doesn't FTL quantum tunneling violate causality?

It seems that a bunch of experiments confirmed that particles tunnel through barriers faster than what would be expected if they were traveling normally at the speed of light. Im referring to a study specifically by the Keller group in 2008 but this seems to be the consensus today (according to Wikipedia at least).

I'm not ready to believe that relativity would fail so quickly and I'm inclined to think that even if FTL tunneling is possible, it wouldn't allow FTL communication. But I fail to see how that's the case.

edit: corrected group name to 'Keller group'

[Assistant] It can't communicate information. Stuff can travel faster than c- like how the Universe has expanded faster than the speed of light- but information cannot be transferred faster than c. Quantum tunneling is random- you can't *make* a particle jump a light year away instantly- so it can't transfer information.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
CMV: "Emotional" TV commercials do nothing in making me want to purchase the product. If anything, it deters me from buying the product.

This is easier to explain with an example: There was just an extremely emotional, over-the-top commercial on TV that showed a family holding hands and laughing over a Thanksgiving dinner, with a narrator talking about important family is. Then at the end, it's revealed it's a Pillsbury crescent commercial.

Another example would be when the son comes home from the war early and brews a pot of Folgers coffee then embraces his mom, both of them crying.

Commercials like this drive me crazy because I do not think they do absolutely anything in making me want to buy the product. I'm never going to purchase Folgers coffee because I'm seeking an emotional moment with my family. Same applies for Pillsbury crescent rolls. It feels so tacky and cheesy that they're almost hard to watch. I just don't understand how people can be sitting around a table in an advertising company and come to the consensus that these types of commercials will sell products.

Also in a weird way these types of commercials feel patronizing (like, "oh thanks Folgers, you really think this is going to work on me") and really irritate me.

Basically, I can't stand them, and they have absolutely zero influence over me as a consumer.

[Assistant]
The thing about advertising is that it's not so much about logic as it is about association. This clearly doesn't work for you, because you are actively annoyed by these types of commercials, so you associate that negative feeling with the product. But for most people, emotional commercials aren't annoying, they're just fine. The goal of the company is for the consumer to subconsciously associate positive feelings--happiness, family, etc.--with the product. This isn't as cut and dry and logical as "Oh, Folgers coffee brings families together, I'd better buy some." It's just that when you're shopping for coffee and see Folgers among the options, they want you to be familiar with the brand and have a generally positive opinion on it. A lot of it is simply exposure You're more likely to buy a product you're familiar with than one you aren't. Folgers wants to make sure you recognize the Folgers label. It may be irrational, since you don't necessarily know more about Folgers than about whatever's next to it on the shelf, but as long as you feel like you do, you'll choose it over other options. And they don't expect you to necessarily even remember the commercial about the son and his mom. They only hope that having seen that commercial will mean that when you see the Folgers can on the shelf, it triggers a positive response in you.

This doesn't work for you, because you *do* remember the commercial specifically because you had a negative reaction to it. But it does work decently well for most people, which is why companies keep doing it.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Lord of the Rings] Do elves play sports or have any sort of athletic competition?

[Assistant] There are several references to Human and Hobbit sports, but only one or two for the Elves. They are described as having athletes, so this would indicate some sort of competition of physical prowess. Likely these are things like track-and-field sports, such as running, swimming, and possibly archery.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [40k] Do the necrons contribute to khorne because they kill things? Or does it not count because they have no emotions? And also, if all emotions ceased to exist (eg necrons effectively kill everything) would the eye of terror disappear?

[Assistant] Sentient life generates the Warp through their emotional energy, which is why it stops at the edge of the galaxy. If the Necron managed to kill everyone else, the Warp would cease to exist, and the Ruinous Powers with it.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: what were Stephen Hawkings greatest discoveries?

[Assistant]
"Were?" This made me think, 'Oh shit, he's dead,' and had to go check.

His branch is theoretical physics, which isn't really about 'discovery' as such. He and other theoretical physicists are all about bringing experimental and observed data from other branches of physics into the context of a wider framework. The supposed "theory of everything." Some of the 20th century's favourite physicists have been theoretical physicists; Hawking, Einstein, Sagan, deGrasse Tyson. Theoretical physicists work at the bleeding edge of what we understand about the universe.

Hawking's work is mainly in astrophysics and general relativity, though he has branched out into quantum physics and particle physics as well. His greatest work is probably his book *A Brief History of Time*, which brought theoretical physics into mainstream culture for probably the first time since Einstein. In the book, he explained phenomenon like the space-time continuum and the speed of light in a way that casual readers and high-school level science students could understand, as well as mathematically proving the existence of black holes and dark matter for the first time. He theorised that black holes do emit radiation, previously thought impossible because of their gravitational pull, then he proved it in both mathematical and layman's terms. As he demystified theoretical physics, he furthered it.

When he does eventually die, he won't be remembered for one stand-out discovery above all others, but for the body of his work as a whole. He has done as much to further the field of physics within his lifetime as Einstein, Newton, Copernicus, Aristotle...


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Central Limit Theorem

I'm an ug sociology student. In our statistical methods in sociology course one subject interested me which is Central Limit Theorem. Does any critical or/and comprehensive artical, journal etc has been written about why  the shape of the population distribution, the sampling distribution of the sample mean approaches an approximately normal distribution ? How can be explained from sociological point of view?

[Assistant] The Central Limit Theorem isn't a product of biology or sociology or any other sort of behaviour of living things. It is a mathematical theorem, with the same rigour and validity as the Pythagorean Theorem or the Sine Law or any number of other mathematical facts. This is because the Central Limit Theorem doesn't say anything about the underlying thing being sampled -- it only says things about the samples when you do the sampling multiple times.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: why are the skins of fruit more nutritious than the insides?

[Assistant]
because fruit aren't intended to be nutritious, they're intended to be tasty, which means the bulk of them is relatively homogeneous fluff with lots of sugar. The skin is the only part which has to actually do something important, so its loaded up with a variety of vitamins and minerals and other cellular necessities to do its job.

same applies to like, why wheat germ is more nutritious than the rest of the grain. The rest of it is just an energy store. The germ has all the parts that grow and do stuff, so all the goodies are found there.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: If Homosapiens survived the last mass extinction how is there almost 8 billions Humans now? Are we all related? Is every human related in some way?

[Assistant] Every human IS related to some extent. That extent tends to be very, very far back. Mitochondrial Eve (the most recent common female ancestor of all humans) is estimated to have lived 150k years ago, and Y-chromosome Adam (male version of the same thing) 200-300k years ago.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[ELI5] Why do ponds and lakes not become swamps after years of season changes

Lakes and Ponds are water reservoirs that are often surrounded by trees, bushes and other plants. During a summer period a lot of "trash" comes into this water, during the fall time plants loose their leaves that often go down to the water surface and later drown. Leaves are being decomposed and every year this cycle repeats.

Why do not all ponds and lakes change into swamps? Obviously some of them with time transform into bogs but majority stays OK.

[Assistant]
When the leaves decompose, the carbohydrates that make up most of their bulk turn back into water (which joins the lake's volume and eventually outflows through whatever outlet the lake has) and carbon dioxide (which outgasses into the atmosphere). The same happens for other organic molecules. What's left is mostly minerals gathered by the plants surrounding the lake, which (on the time-scales we're talking about) is essentially just plant-driven erosion. The only time this doesn't happen is if the plant material can't effectively decompose, typically because the water is too acidic or too low on oxygen to allow microbial growth (which is how you get many of the wetlands that actually exist in the world).

Many of the remaining minerals (particularly earth metals like sodium) are highly water-soluble, so the rate at which they outflow scales with how much is currently in the lake (which is why lakes that have an outflow are, almost without exception, freshwater). That leaves a few minerals that don't dissolve very well even over many years. Over geological timescales, this stuff does build up. As with any other erosion, highlands wear down and lowlands fill up, and eventually your lake at the bottom of a valley becomes part of a marshy plain full of silt. But this takes a long time, and other forces (primarily plate tectonics) are acting to push some parts of the land back up, too, in a way that can (and sometimes does) prevent this process from reaching its endpoint.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [ASOIAF] Why has there been little to no technological innovation in the past few thousands of years?

[Assistant]
There has, but its mostly not visible.  Westeros is in an age equivalent to the Dark Ages after the fall of the Roman Empire, which is represented by Valyria.  Quite a bit of the technology of Valyria was preserved, but access is limited due to an education gap.  The ability to read and write is most certainly limited to the upper class and perhaps the merchant class, so innovation is probably limited to that area as well.

So civilization is slowly coming back from the collapse of the cultural, technological and economic superpower, knowledge is limited due to low literacy rates and thus innovation is slow.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Why is the video editing greenscreen... green?

Why is it green and not red or blue or anything else?

[Assistant]
You need a bright primary color, one that most people aren't going to wear or have on their bodies, because all of that color will be deleted when you edit the film. You can use blue, but green is less likely to cause problems with people's eyes or fashion.

Red is worst, because it can cause problems with erasing some people's skin tones at times.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: What is the function of the 3 digit "security code" on your credit card when you have to provide it every time you use your credit card?

IIRC, it used to be a way to prevent fraud by people who had your cc number and expiration (say from a restaurant receipt) but not your physical card, but today there are very few people on earth who have my cc number and expiration but don't have my 3 digit code.

At this point it seems like nothing more than a 3 digit extension of your credit card number.

[Assistant]
Its for what are called "Card not present" transactions. Its an additional layer of security to prove you have the physical card.

When you go to a store and pay with your card, you have teh card, nothing else is really needed. Thats why you don't use your CVV. They physically can run the card.

But, what about when you buy a shirt online? This is a "card not present" transaction.  How does the merchant know you have the card and its not fraud or scam just with the number? Well, thats where the 3 digit CVV comes in, it proves you have the card and fraud is much less likely.

None of this prevents fraud entirely, but it significantly helps reduce it.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5:When jumpstarting a car, why is it important to always start with the positive gauge (red) ?

Every one always told me to start with positive, but i never understood the reason...

[Assistant] Sometimes, when you make the last connection, a spark jumps from the cable to what ever you're about to clip it to. If you start with the red cable, then the last connection will be made to an unpainted metal part of the car. That way, if a spark occurs, it hits the metal part of the car, rather than the battery, which reduces the chance of igniting hydrogen gas coming from the battery.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Stranger Things] What is the Upside Down?

I understand that its a different universe, but how does it mirror Hawkins? Most of the buildings are there, but damaged by the Demigorgons and the MindFlayer. The lights are still on, but you could say thats the mysterious energy that flows through the Upside Down. So was it ever like Hawkins? Did it have people? Were they all consumed? Or is it built on some copy of Hawkins that was created by Eleven when she created the gate? If so, how did it become so infested so quickly? Demigorgons seem to need hosts to reproduce, and there was just one of them at first. When did the MindFlayer get there?

[Assistant] There probably isn't a perfect way to describe it, except maybe asking the Duffer Bros. To me it's like a shadow. It's affected by the thing casting the shadow, but can't do anything itself. And then the Sci-Fi experiments come in, and the shadow can begin acting itself.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
How do we know neutrinos have mass?

My own answer is: since the Super Kamiokande and SNOLAB we know that neutrinos can change flavours. My reasoning is: solar neutrinos are all electron neutrinos originally. To change flavour an infinitesimal (but non-zero) amount of time needs to pass (simply to have the 'room' to switch). Particles moving at c don't experience time. All particles with mass have to move slower than c. Hence, neutrinos have mass. Is that the gist of it?

[Assistant]
Your understanding is more or less correct.

The key piece is that neutrino oscillation implies that the flavor states are not the same as the mass states. This means that flavor states are mixtures of the mass states, and vice versa.

The existence of flavor oscillations (observed as a deficit of solar electron neutrinos... because some of them turned into muon neutrinos and tau neutrinos) indicate that this is the case. So the evidence for neutrino oscillation is that we see a third of the expected electron neutrino flux from the sun, because they've turned into other flavors of neutrinos, and neutrino oscillation is the evidence for neutrino masses.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
In which European countries are faculty well paid?

I'm a tenured prof in a STEM field at a major university in the US. I make around $130K per year plus summer salary. After taxes and benefits, that works out to about $8K per month on avg plus around $1.5K per month contributions to my retirement account.

I am well paid and like my job, but don't like living in the US and don't want my kids to grow up here.

I looked into jobs in Europe, but many countries seem to have much lower pay for faculty. I'm willing to take a lower salary to live in Europe, but not half of my current salary!

In which European countries could an STEM faculty (equiv to associate prof in US) expect to receive at least 6000 Euros per month after taxes?

[Assistant]
If you manage to get a W3 professorship in Germany (its tough out there), you'll likely have something between 6k and 8k  (gross!) per month, and a 13th salary at the end of the year. This doesn't mean you'll get a net amount of at least 6k on your bank account (if you have 8k gross, its probably going to be around 5k net), BUT there are some perks:

-healthcare is 100% free (e.g., paid with a small amount out of your gross salary, and as you are a public servant, you are "privately" insured and get the best healthcare possible)

-you don't have to pay a single  into a retirement account (only if you want to). As you are a public servant, you'll automatically get ~70% of your last salary as a pension.

-many many other things as others mentioned (free college, free education, subsidized daycare, no guns, etc. etc. - this is for you to google).

Hence: you'll likely get less money on your bank account each month. Your quality of life will be at least the same, if not better. For further information, google "W3 professor Germany". Be prepared to learn some German, although English is commonly/increasingly used in the educational sector.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: With all our technical advancements in modern materials and engineering, why do we still use wooden poles to hang up wires in the US? They seem so primitive.

[Assistant] They are cheaper to install than metal or concrete poles for the smaller spans, and will last longer if nobody hits them since they are treated to last longer since the base won't rust/degrade as badly as the others.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
CMV: Diversity in the workplace is important but it should not trump the most qualified person for the job.

For this hypothetical example I will lay out two assumptions and an outcome.

When interviewing people, lets say (1) there is always a diverse group of people (age, race, and gender) interviewing. Lets then say (2) the people interviewing have no idea what the people look like or their age.

If, in this scenario, the same type of person (age, race, and gender) is selected every time because they were the most qualified person being interviewed at the time. Is there anything wrong with the outcome? Or is the workplace affected in any way?

[Assistant]
The problem with this view is that it paints diversity as an oppositional force to hiring the most qualified employee, when that isn't really the case.

A well-studied effect is "similarity bias" or "affinity bias"; basically, people like others who are similar to them. This effect is very pronounced in hiring; employers tend to artificially favor employees similar to them (less diverse) even if they are equally or less qualified. Promoting diversity initiatives can actually *counteract* this similarity bias and lead to better hiring and more diverse hiring at the same time.

Further, the idea of a "most qualified person for the job" is extremely nebulous and basically impossible to determine. Quality as an employee is subjective and employers are terrible at hiring; for instance, the silicon valley trend of "lateral thinking puzzle" style interviews was huge and popularized and turned out to be *awful* and only good for weeding out candidates who did not think exactly like the interviewer, limiting both diversity and quality of employees. At best, the "most qualified person for the job" is extremely fuzzy and there are probably multiple candidates who could be most qualified, which means interviewers *always* have the option to pick for reasons beyond "objective" quality.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] Do honeybees, wasps and hornets have a different cocktail of venom in their stings or is their chemistry pretty much all the same?

[Assistant] Bees, wasps, and hornets all evolved from a common ancestor, so their venom is similar. Basically, their venoms contain irritants that irritate the victim/the individual who was stung. Phospholipase A2 and mellitin are the allergens that cause a bee sting. Antigen 5 is the main venom of a wasp/hornet. Both a bees and a wasps venom contain hyaluronidases, but the combination of compounds really dictate how the stings work/feel. A bee will inject a venom that basically causes inflammation - similar to an allergic reaction. A Wasps venom breaks down cell membranes and they can sting multiple times which is why they hurt so much more: they do actual damage. Finally, bee stingers stay in the skin, and you should always remove them. Hope this helps!


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5 How did movie projectors display reels in sequence without any gaps?

I don't know anything about the technology of film projectors. But I've heard movies described in terms of number of reels. I understand this only regarding the length of the movie.

I don't understand 1) did the distributors send a movie in multiple reels and 2) how did the projectionists display the multiple reels without pausing in between to reload the machine?

[Assistant] Projection booths would have more than one projector. Both projectors are aimed at the screen the same way.  Within the movie there was a cue for the projectionist to know when to start the next reel.  You no doubt had seen that cue not realizing what it is, it is typically a quick flash near the top right corner of the screen.  There was a second dot that would flash again to let the projectionist know it is time to switch completely to the other projector.  There are time stamps that are published for the projectionist to know about when that transition occurs.  If there are more that 2 reels the same sequence happens again back to the other projector.  The reel would be changed after the rewind of the previous reel.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: North Korea-what's the situation with its nukes, how "good" is its army and who would win in NK vs USA?

[Assistant]
There is no doubt the US could destroy North Korea in any sort of war.

The question is, could they:

* do it without suffering politically unacceptable losses?
* do it without massive civilian losses in South Korea?
* do it without drawing China into the conflict?


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: Non-Euclidean Geometry

I don't know where to begin. What is it? How does it work? Is it a thing in real life?

[Assistant]
Draw a triangle on a globe. Measure its angles. They don't add up to 180.
That is non-euclidean geometry, right there before your eyes.
Useful for many things, including, how do we get this plane from San Francisco to Tokyo the fastest? Answer: go over Alaska.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Halo] Why doesn't the UNSC appear to reverse-engineer Covenant technology?

They've got plenty of examples of the stuff lying around. Capturing weapons, armor, even small ships is possible, sometimes even incidental. Even if the UNSC isn't going to switch to plasma weapons, there must be something of value in their energy storage or materials science. This seems like a missed opportunity?

[Assistant]
Given that Covenant tech is almost all reverse engineered from Forerunner "relics," there's a solid learning curve involved. But really the main problems aren't from reverse engineering the tech, it's restructuring their entire manufacturing and training setups to take advantage of the advancements. (Remember the whole "we're at war" thing)

In spite of that;

UNSC star ships apparently used the rotating centrifuge model for artificial gravity prior to first contact with the Covenant. This was one of the first things the UNSC integrated into their new ships. The Mjolnir armor's energy shield is reversed engineered from Jackal's personal shields. The UNSC Infinity was built with a Forerunner slipspace engine, among other bits of Covie tech.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
[Warhammer 40k] Since the Dark Mechanicus aren't stagnant like the Adeptus Mechanicus are, won't Chaos eventually win through technological superiority?

Any more than they already have, I mean - the Imperium today produces more than enough war, stagnancy, plotting and pleasure/suffering to feed Chaos.

[Assistant]
You can't do much research when your laboratory decides what rules of physics it will adhere to at the moment. And it changes very often.

Also, Chaos does not like other following chaos, they are just as likely to be killed by the Imperium as by other Chaos followers(if not even more so). Death tends to stop research really well.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
CMV: People that take naps regularly don't get enough normal sleep.

This is purely anecdotal based on a few of my friends and my own experiences.

Personally the only times I end up taking a nap is when I am feeling tired beyond reasonable means for that day. This is usually due to not getting adequate sleep the night before. When I end up taking a nap it throws off my sleep schedule for that night. Say I end up taking a nap around 7pm, I'll then wake up around 8pm, feel a bit weird/flustered, then proceed to go to bed 2 hours or later past my normal bedtime.

Regarding my friends in question, they both take at least one nap per day. One of them is known to take multiple naps in a day. They seem to always be in a state of wanting to nap, taking a nap, or just finishing up a nap. They also talk about napping at least once every time we hang out. Now where my angle comes in is when we are hanging out and doing an activity like playing a board game or running a DnD session. I've caught them falling asleep during the sessions on multiple occasions. As a fellow player this frustrates me. The one friend that claims to take multiple naps in a day, I regularly see his steam account start up a game around 2am if I happen to be up at that time. I think the single nap taker has a more concrete sleeping schedule but I haven't really pressed them on it.

Point being, seeing these two peoples activities and susceptibility to fall asleep when doing an activity combined with them worshiping naps has led me to conclude that the reason they need to nap so much is because they are they regularly don't get enough quality sleep at night. and if this is the case then what is causing it? I also don't think this is a case of narcolepsy as I have another friend that does legitimately have narcolepsy and he will fall asleep at the table in 10-60 second chunks. The two I mentioned will tend to to cosy up before they conk out.

I've done a little investigating as to what naps are and I probably should do more. But this is causing me noticeable amounts of annoyance when hanging out with them. In the end I don't want to be put in a position where I look down on them and others because they nap. But from what I've gathered with their interactions plus my own personal experiences with naps have drawn me to the conclusion above. Please change and open my mind and help me respect naps.

[Assistant]
Most mammals are polyphasic sleepers meaning they take multiple naps per day rather than one long nap. There are theories that we forced ourselves out of this type of sleeping habit to align with the 9 to 5 style of day that we are currently apart of.

People like Tesla, Edison, and Da Vinci were polyphasic sleepers. Some cultures still encourage a nap each day, siesta, instead of just one long nap. The body doesn't care if you get your REM sleep all at once or if you do it in spurts. All that matters is that you get it.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] [Dune] So Arrakis is the only source of Spice, which is essential for FTL, longevity and the basis of the Galactic economy. So why is it treated like an undeveloped backwater? Why wouldn't the Emperor make it his capital?

[Assistant]
First off, the more desert, the more worms. The more worms, the more spice. And for most of human's history with the planet, it was impossible to remove the worms from Arrakis and start spice production elsewhere. You don't pave over a water source because you want to live near it.

Second, YOU try maintaining comfortable human living conditions on a planet-wide desert. Earth's most hostile deserts are a tropical beach at sunset compared to Arrakis. Sand is in EVERYTHING, constantly eating into any materials both natural and human-made. You breathe it, you eat it. And it does excellent work in breaking everything down. The heat destroys whatever is left. Sure, it's physically possible to build and maintain comfortable housing and cool buildings, but the cost would be astronomical. Not to mention the Guild getting their share of the CONSTANT imports that would be necessary to maintain this artificial construction.

And third, it does become a seat of power and civilization over time. Arrakis is eventually terraformed into a paradise world perfect for human life. The results are basically the genocide of the worms and the loss of everything that made Arrakis what it was. (it doesn't last forever though, the desert and the worms return)


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5 why fabrics get darker when wet?

I've always wondered why fabrics are darker/ more vibrant when wet? Is it literally (no pun intended) the saturation of the color increasing? Or perhaps a refraction of light? ELI5 please and thanks!

[Assistant]
Here's an easy experiment.  Place a drop of water on a paper towel.  Notice how the wet spot looks dark?  Now hold that paper towel up between you and a source of light.  Notice how the wet spot looks bright?

The water increases the ability of fabric (or a paper towel) to transmit light, which means there's less light to be reflected back toward you.  So the wet spot will look lighter or darker, depending on whether you and the source of light are on the same side of the fabric, or not.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
What is the speed of magnetism?

Something I was pondering yesterday, and couldn't get a straight answer by googling the question, so I thought to come here.  Basically, here is the problem, and i'm curious of an answer.

Say you have a laser beam, attached to a switch, which is attached to a power source.  A mile away from the laser, you have a photoresistor, attached to a computer to record the time of the wave arriving at the resistor.

Next to this laser, you have an electromagnet, which is attached to the same switch and power source.  Yet again, a mile away from the electromagnet is some receiver that detects magnetism, and is attached to the same computer to record data side by side.

My question: When the switch is pressed, will the magnetic field arrive ahead of light?  Do not include resistance of the wire, or time it takes for either to create a magnetic field, or a beam of light.  Purely speed.  Does magnetism have a speed?

[Assistant]
It sure does.  And you may (or may not!) be surprised to know it travels as the same speed as light, c.  The main reason is that the force carrier for the electric field is the same force carrier for the magnetic field (the photon).

Electricity and magnetism were found to be manifestations of the same fundamental force way back in the late 1800's by Maxwell.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
Is the residue left from an effervescent vitamin tablet salt, or vitamin C?

My friend is aware of how much salt these tablets have, so he always throws away the crystalline residue left in the bottom of the glass.

I was thinking that since the salt is what actually dissolves the tablet when put into water, the residue at the bottom could actually be the vitamin C he wanted in the first place.

Does anybody know for certain? Does anybody know how well ascorbic acid dissolves in cold water? Could it form a precipitation at all?

[Assistant]
Ascorbic Acid is extremely soluble in water (50g per 100 mL, i.e. 50x more than you probably need). As is table salt (NaCl)

Most of the reactants from fizzing are also extreme water soluble. Most of them are based around citric acid and Sodium and Magnesium Carbonate. What is most likely left in the bottom of the glass are pill binders, which are usually some kind of fats+gums, like Magnesium Sterate.

There is a chance of some Magnesium Carbonate precipitating out, but generally the solutions are all too acidic for that.

TLDR, the stuff in the bottom of the glass is mostly the fats and gums used to hold the pill together. It's not NaCl or Ascorbic Acid.


[System] Given the following post, respond as if you're commenting on Reddit:

[User]
ELI5: what does it mean to overclock a CPU?

what does it mean to overclock a CPU and what are the pro's and con's?

[Assistant]
Overclocking means making your CPU to work faster by increasing the default clockrate (GHz). Increasing the clockrate makes the CPU less stable (might crash without reason) and more hot (requires better cooling).

If you find the sweet-spot (stable, not too hot, maximum GHz) you're gaining tens of percents of performance increase for free.

It's a lot easier than you think. Basic overclocking is basically just typing a higher number in the CPU settings (BIOS).

I would compare it to tuning your car engine to make it faster. When you're going faster, you need better brakes and stuff. If you make your Fiat Punto go 500km/h, it will became unstable without modifications.


[System] Given the following post, respond as if you're commenting on Reddit:

[User] ELI5: Is there actually any significant difference in the chemical composition of household cleaners which claim to be for the "kitchen" or "bathroom", or are they all basically the same thing?

[Assistant]
Not in their chemical composition but in their physical composition. Bathroom usually means ceramic tile and porcelain and kitchen usually means linoleum, stainless steel, and veneer cabinetry.

Ceramics are hard. In fact they are some of the hardest materials found in most homes short of glass, silica, or diamond. So a bathroom cleaner will usually contain a softer but abrasive agent to help scrub dirt and grime off of tiles but without scratching them. Because tile and porcelain are so hard, you can use some pretty abrasive stuff without fear of scratching them. However if you use them on plastics, linoleum, or veneers they can scratch and gouge them.

Some of the most abrasive cleaners will have warnings about which surfaces they can be used on. Their abrasive qualities however make quick work of hard water stains and soap scum such as in a shower or toilet. You wouldn't want to use them on a stainless steel sink though.