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

[User] ELI5: What is emulsification and how does it work?

[Assistant]
An emulsion is when two liquids that dont mix or dissolve in each other (immiscible) are put together and then mechanically mixed so that even though they remain separate at a small level, theyre still pretty well mixed.

The most familiar example is probably oil and water. Oil will float on top, and stirring a little doesnt change it. If you stir and shake a lot, the two liquids form droplets that can be all randomly jumbled together.


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

[User]
I still don't understand when it's proper to use *affect* vs. *effect*.

I still don't understand when it's proper to use *affect* vs. *effect*. I have googled it so many times, and yet when it comes times to use the words I have no clue. Please ELi5 it to me and explain it so I never have to question this again.

[Assistant]
Affect means to influence or change. Think "a for alter". Barring some psychology-specific lingo, it can only be used as a verb. Think "a**v**ect for verb".

An effect is a result, think "e for end". To effect is to cause an effect.


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

[User] [Warhammer 40k] Why there are not any Chaos Eldar, Orc or Tau forces?

[Assistant]
The Eldar can be divided up into two factions

The good Eldar who eschew desires and walk a straight and narrow path to avoid any corruption. These are mostly your exodite and craftworld Eldar. Now granted these are still not very nice in appearance as they use creepy warp based farsight to take drastic  actions to prevent some unknown tragedy and they get pissed at everyone for not understanding. So good in this case means not in bed with chaos

The bad Eldar or Dark Eldar barely survived the fall of their race and as such She Who Thirsts has her hooks in all of them. Now in order to avoid having chaos suck their souls out like a delicious Eldar Juice box they sacrifice the souls of others through some pretty horrific torture sessions. Think of them as hyper-sadistic space vampires who instead of blood feast on your misery, suffering, and your soul.

Now to the Imperium and probably most non Eldar  these two are basically the same.

The Tau barely have a warp presence  as such Chaos tends to ignore them. Think of it this way  you are at Golden Corral  are you going to hit the buffet line? Or are you going to go scrounging for crumbs? Also the Tau dont have a large enough presence in the Milky Way to really warrant the attention of Chaos.

Orks  follow Gork and Mork. Orks will fight daemons, men, Eldar, other Orks, Tau, Nids, and pretty much anything. The real magic of the Orks is  they won. They have no victory conditions, they have no weird species destiny, existential crisis, or desperate mission. They fight  and then they fight some more. If some bizarre reality warping happened and transposed chaos and the Imperium? The Orks wouldnt care. There is no great struggle for them  just a good fight and a tall glass of fungus beer at the end of the day. Chaos cant offer them anything  no one can. (Though there was that one Ork warband who wandered into the Eye of Terror  they are stuck on a daemon world where they fight and kill eachother every day and are resurrected the next day. The Orks think its pretty awesome.)

TL;DR  Bad Eldar exist, Tau have small warp presence, and Orks cant be tempted by Chaos.


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

[User]
ELI5: If the brain lacks nerve endings for pain, how do we feel headaches?

I've heard that the brain itself has no "nerve endings" ^((terminology?)^) for touch/pain.  I know when I feel, I can tell where on my body the feeling is.  And, I know when I have a headache, the pain seems to come from where my brain would probably be.

So, why can I feel there, if I can't feel there?

P.S.:  I've heard the nerve endings we feel are actually in the nasal cavity, but most people just grow up imagining them as the head since pressure there works, is this true? or...

[Assistant] There are many types of headaches. The most common is tension headaches. These don't originate in your brain. They come from the pain receptors around your skull, not from your brain. Sinus headaches come from inflamation of your sinuses. You do have pain receptors near your brain. If you have a brain hemorrhage which is putting pressure on the inside of your skull, you will feel it. Your brain isn't doing the feeling, the receptors around your brain are doing the feeling. Dehydration causes headaches because it causes your brain to shrink and pull on the inside of your skull. Headaches can also be caused when the networks in your brain that are associated with processing pain are activated.


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

[User]
Voyager I is now 11 billion miles. How is it possible that we are still able to receive signals from it?

Voyager I is an incredibly long distance away. It takes light from the Sun about eight minutes to reach Earth - the signals from Voyager I take more than 16 and a half hours. I don't understand how they are not too weak to detect. Anyone able to give some insight?

[Assistant]
The system used to communicate is a bidirectional system which is supported on-earth by NASA (called Nasa Deep Space), which is a really really big radar (EDIT: Antenna) system pointed to the Voyager, ready to capture the signal.
As like any other electromagnetical wave, the radio waves travel at the speed of light; so the time needed for this signal to arrive depends on a lot of things, such as the straight-line (so to say) distance from Earth, and you can calculate it using the equation

    t = D/c

where *t* is the time, *D* is the distance and *c* is the speed of light.
So if you know the time, for example, you can revert the formula to know the distance, using

    D = t *x* c

The probe has a relatively big dish-antenna which uses radio frequencies in a certain bandwidth (S-band) to obtain better communication and not to be confused with any other radio signal. So, even if they're actually really weak, we can decode them as we know their exact wavelength.


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

[User]
[Marvel Cinematic] Who owns the rights to the Avengers toys we see in film and on Agents of S.H.I.E.L.D.?

I am assuming Stark Industries owns Iron Man, and S.H.I.E.L.D. owns likenesses for Hawkeye and Widow, and the US Government owns Captain America/Iron Patriot... but who would be able to legally sell Thor and Hulk toys?

[Assistant]
A company called Marvel, which creates and distributes action figures and t-shirts that you see and usually even some TV shows.

Seriously though Marvel put themselves in as a company in their own universe because of the alternate universe dealy.


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

[User]
[Legend of Zelda] Why is it called the legend of Zelda

The story focuses almost exclusively on link, so why is it Zelda's legend?

[Assistant] Link's name is almost never recorded in the legends. He's always referred to as the hero, hero of time, fairy child, forest child, or sometimes the storyteller will use their own name or a name from their audience. Zelda, being a noble, is important enough to get her name written down, and it's the same each time.


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

[User] ELI5: When people talk about nuclear waste, what are they really talking about? Whats in those scary barrels buried deep in a bunker if it isn't "glowing green goo?"

[Assistant]
There are different classes of nuclear waste. Low level radioactive (rad) waste is broken down into different classifications. It can be anything from gloves and paper suits worn in containment or resin beds or filters. Its disposed in special facilities based on its classification.

High level waste includes spent fuel. Nuclear fuel is uranium pellets (sort of the size of an eraser on top of a pencil) that are assembled into rods and then the rods make up a bundle. Once the fuel is removed from the core, it goes into spent fuel pools, which are literally just pools of water. The spent fuel will hang out there for a while, just chilling (literally and figuratively). Eventually, the rods will be moved into longer-term storage. This was originally supposed to be Yucca Mountain (in the US at least). That facility was paid for by operating nuclear plants, but was never opened. Instead, nuclear plants usually move their spent fuel into dry cask storage. This is a big coke can looking thing that just holds the fuel. The fuel is, remember, still in rods. So you just plop it in the giant coke can and seal it up. They hang around outside the nuclear plant. Not in a deep bunker, just like chilling outside.

Although it sounds like theres just nuclear waste everywhere, its important to keep in mind that its not a sludge (if youre talking about fuel). Its a stable solid rod. And the amount of rods were talking here is not a lot. In fact, its really not an issue at all for plants to continue to store spent fuel on site, its just kind of a paperwork pain.

At this time, theres no way to recycle spent fuel in the US (I dont think).


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

[User]
[Thor Ragnarok / Infinity War] Had Thor not crossed paths with Thanos at the end of Ragnarok, what was his plan going to be when he got to earth?

In the end of Ragnarok, Thor inherited the title of King over the Asgardians. His first move as King was to head over to earth. If he successfully made it over there, what was he going to do? Was he going to catch up with the Avengers? Was he going to choose earth as their new home?  Had that been the case, how do you think that would have gone over? It's a revolutionary to have Wakanda share their resources. But then to become neighbors with Asgardians, that's a whole new ballpark, even for MCU earth.

Tell me your thoughts.

[Assistant]
First thing he probably do is contact Stark who's bankrolling the Avengers. He'd probably learn of the Sokovia Accords and it's aftermath. He'd bit tad angry at Stark but requests an asylum for Asgard, preferably Norway. Ross learns that Hulk and Loki are onboard the Statesman and invokes the Accords to bring them in. Thor declines, via sending a very, **very**, ***very*** angry letter to the President. President pardons Loki and Hulk in exchange for Asgardian tech and annual pay for an embassy in Norway. Norse religion becomes more popular again. Few months later, Thanos strikes with his army and Black Order, devastating New Asgard, New York, & Scotland. Stark goes missing and a barely alive Thor is picked up by the remaining survivors of New Asgard. He seeks Heimdall who sends him to Nidavellr with his life supplementing the dark energy needed to activate the Bifrost. The Guardians are ambushed on Knowhere by Thanos who has the Power, Space, and Reality Stone.

You've seen the rest.


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

[User]
[Spider-Man] Spider-Man would win the Olympic gold for gymnastics, right?

Would his natural athleticism be enough to overcome the fact that hes not trained in gymnastics? Is there some technique qualifications he wouldnt meet?

Bonus: I cant think of another superhero who could beat him in gymnastics, is there one?

[Assistant]
He *could* pull off any movement without breaking a sweat, and turn in a 10/10 performance every time, as long as he knew the criteria by which he was being judged. Give him an afternoon to watch some tapes, and he's a gold medal guarantee.

There are other heroes who could also turn in super high-level performances, like Daredevil, Beast, and Nightcrawler, but even they aren't as good as Spidey.


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

[User] ELI5: Why is the Queen of England's husband not the King of England?

[Assistant] There are two different kinds of queens: queen consort and queen regnant. A queen regnant is a ruling queen (like Elizabeth II) whereas a queen consort is just the wife of a king. Traditionally, king doesn't have the same break, there is ONLY a king regnant. In the UK, the husband of a queen doesn't get any official title, unless he is granted one (and, yes, he could theoretically get the title King if parliament so chose).


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

[User]
ELI5 Difference Machine Learning/ Deep Learning

I'm a teacher and I'm trying to explain the difference between Machine Learning and Deep Learning. Can someone help me?

[Assistant] Deep learning is a specific part of machine learning which uses multiple layers as part of a neural network. Machine learning in general doesn't need to use many layers or follow a neural network architecture at all.


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

[User]
There is no point in voting because one vote never makes a difference. CMV.

Whenever I say this, 100% of the time I get the following response:

"Yes but if everybody behaved like you, no one would vote, and then one vote WOULD make a difference".

My answer to this alternates depending my my mood:

"So?"
"But will everyone do that?"
"Thanks for the compliment that everybody in society follows my lead and won't vote if I don't. The problem is that I can't see it"

Please consider the above responses before making this argument.

Also consider the relevance of: you are more likely to get run over on the way to the polling station than your vote to make a difference.

Thanks!

[Assistant] You seem to have the assumption that your vote only matters if it changes which candidate wins election.  However, politicians look at vote totals to decide what positions to support/oppose.  So every vote - even for a 3rd party- influences future political moves for years to come.


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

[User]
ELI5: How is every person's voice unique?

The title says it all.

I was just wondering how it's possible that every single person's voice is so unique to each other? It's all the same systems, the same organs, so how does everyone sound so different? I understand it to a certain extent, but would like to have it explained!

[Assistant] Same organs but all shaped differently. The size of your voice box, thickness of your vocal chords, length of your throat, size and shape of your mouth, size, shape and positioning of your tongue, even your sinus passages, all play a role in how your voice sounds. And all of that is different for everyone.


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

[User] [Halo: Reach] Say Emile did manage to hold off the Covenant forces so Noble 6 could escape, what happens differently in the master chief trilogy?

[Assistant]
Not much. Master Chief made it through everything on his own too, and made the difference. Remember that there were more Spartan IIs alive than Master chief too. Noble 6 was hardly the only surviving Spartan III, either.
Not much use for them in space combat, but they did perform a lot of infiltration and sabotage after we lost the Battle for Earth, before  the portal to the Ark was discovered.


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

[User]
[Batman: Arkham City] Why did the thugs use frequency jammers?

How did they know that their jammers could be used to disrupt Batman's cowl technology? They would have had access to Batman's tech or at least know Batman has that technology but isn't it some big secret? If they were just jamming all cell signals the. wouldn't the times he's underground have jammed his signals as well?

[Assistant] I don't remember the timeline exactly, but if they got that tech around the same time they got all their guns, then it was Strange supplying them. Maybe Batman's cowl tech isn't a secret; maybe the thugs are just taking the jammers on faith.


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

[User]
ELI5:The whole black person watermelon thing.

Watermelon is straight up delicious. Everyone of varying colors loves that shit, so why is it a racial stereotype thing? Does anyone actually know?

[Assistant] Well we're still feeling the ripple effect from old racism and slavery. Watermelon originally came from South Africa and spread through most of Africa in ancient times. It was the moors who brought watermelon to Europe and early American settlers who brought it here to the USA. When slavery was at its peak, watermelon's popularity in the states also rose dramatically because African slaves would be inclined to have food from their native homeland (them and their ancestors ate watermelon pretty regularly). Proponents of slavery would use the watermelon as an iconic symbol to push their agenda, "all you need to keep a slave happy is a watermelon, so obviously they are subhuman since us white folks need more than just watermelon to be happy."  After slavery ended here in the us, there were still plenty of racial overtones that continued on with the watermelon.  You are right that it is complete bullshit, one study showed the African Americans only account for 11 percent of watermelon consumed in the us.


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

[User]
Companies selling tasers/stun guns advertise that the electricity will not travel through one person to another (ie if you tase an attacker who is grabbing you). How is this possible?

I've been looking at tasers and stun guns online and just read this on a website selling self defense products: "Should the attacker be touching you, the current will NOT pass to your body"
I'm having a hard time wrapping my mind around this and want to be sure that this claim isn't false advertising.

[Assistant] The current will take a path between the two barbs or prongs that make contact with the target.  If you somehow managed to stick an attacker with one barb and yourself with the other nothing would happen until you touched each other and completed the circuit.  It is the same reason lightning travels down a lightning rod and not in several laps around a wood frame house.  Path of least ohmic resistance.


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

[User]
Feeling like I am in exile, how did you cope moving to a small city for an academic position?

I know this applies to anyone having to move for jobs, but in academia jobs are especially scarce so I wanted to ask here.

I am in my 30s and I am from the largest, most lively city of my country. Very pretty, always something to do. Then I moved to another country for my PhD, lived in the capital for 7 years. Again, very lively, parks, events everywhere.

After searching (and failing) for a permanent job for so long, I finally found one in a smaller city. Its a great job, the university has great reputation in my field, I have decent colleagues. It makes sense to stay here at least a few years and aim for promotion.

But this city is just so plain. I have visited it before with friends but living here alone is a completely different experience. There is nothing historical or beautiful, its just concrete everywhere. When I look at their best restaurants or new cultural events, its just so pathetic.

I know I should be grateful for finding a permanent academic job but I just feel like I am wasting my life here.

Anyone in a similar position? How did you cope?

[Assistant]
Every place has its strengths and weaknesses.  Some jobs here in the U.S. in more "rural" areas won't have any of the fancy stuff the "big cities" have, but will have some amazing places for a wide variety of outdoor recreation. Are you within driving/public transpo distance of the "bigger cities" you desire?

Try and find out what's "great" about the area where you are.  If it doesn't match with what you want out of life, go on the market in year 3 and test the waters to see if you can move to an area more your liking.

If you can't "get into" whatever is "great" about the place, you'll be miserable in the long term, and, IMHO, life is too short to make that your "final" gig.

YMMV.


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

[User]
What's the current feminist take on OnlyFans?

I recently listened to a podcast on the book "The Second Sex" by Simone de Beauvoir and how it was a seminal text for modern feminism. The subject/object dichotomy accentuation was interesting but I was wondering how/if that would apply to the modern day advent of online sex work(onlyfans). More specifically: are women the subjects or objects when choosing to get an onlyfans(or maybe sex work in general??). Are they practicing self-autonomy by choosing to do such work or are they objects subjected to the whims of men--specifically through men wanting certain beauty standards, fetishes, personality traits etc... What's the modern feminist consensus on this topic?

[Assistant] There isnt a consensus. Sex work is one of the most contentious issues within feminist philosophy and politics today. The two perspectives you outline roughly correspond to the sex positive and sex negative perspectives, but there are many shades between those two.


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

[User]
ELI5: Why do major cell phone carriers allow companies like MetroPCS, Cricket Wireless, Boost Mobile, etc. to resell their network?

And for a cheaper price, too? I don't understand.

[Assistant] Metro, Cricket, and Boost are owned by T-Mobile, AT&T and Sprint, respectively.  So it's basically them selling their networks to people who are more likely to pay cash money for a phone + service.  Post paid customers usually pay by debit or credit and sometimes pay their bills after the due date.  Meanwhile most prepaid companies have a set date to pay or else the customer gets cut off.


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

[User] ELI5:why do dogs sniff the ground and have to find the perfect spot before they poop?

[Assistant] They are aligning their poop with the magnetic polarity of the earth.. Dogs true sixth sense Is an ability to smell magnetism.  Look in your backyard or any park for that matter.. All dog poop points to magnetic north.


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

[User]
CMV: Graveyards are not necessary, are terrible for the environment and can be converted to more usable space like parks, playgrounds or housing. Religions should agree to more practical approach instead of burying people in the ground

Graveyards are creepy, you should pay tax for your related family members and with more people dying ( potentially infinite number ) the size of the graveyards should grow. The larger the graveyard, the more unusable space it becomes. My opinion is that root cause of the issue are the religious traditions. All religions should agree to alternatives of burying people in the ground ( like cremation or aquamation ) so we can build a ,lets say, park instead of avoiding to walk near the graveyard region. I mean i understand all those catholic, orthodox, muslim etc religious traditions, i also understand that those traditions are stubborn to changes, but maybe they should be altered for everyone's good.

[Assistant]
First, a grave isn't used forever. Usually what happens is that after 1 or 2 generations the descendents stop paying for all their ancestors so those spots get reused (this may differ, as different countries might handle things differently). In most of the developed world, the population is more or less stable so the land requirement for graveyards should in theory remain stable.

Second, burials have been a tradition encountered among most human civilizations for thousands and thousands of years. This is not necessarily a reason to keep doing it, but it does give you some perspective.

And third, graveyards exist because people are spending money on them, are voting for them, are supporting them. At the end of the day, they're a place where ceremonies take place, where families gather. Isn't that a healthier thing for the community than a big shopping mall for instance?


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

[User]
[X-men film] What happens to the stuff in Mystique's pockets when she changes shape?

I was watching the 2000 X-Men film and there's a part where Sen. Kelly and Mystique (in disguise) are flying in a helicopter. Kelly ends a cell phone call, hands it to mystique (still in disguise), she puts it in her inside coat pocket... shortly after she changes into her true form and kicks Kelly around.

So.. What happens to the objects that she puts in her pockets when she makes those changes?

[Assistant] Mystique is able to change shape in rather dramatic fashion, and while she mostly sticks to humanoid forms, she doesn't have to (as seen by her ability to morph into fabric).  When she changes back to her "natural" form there is no reason to believe she can't generate pockets or other folds easily.  She could morph a small pouch that perfect fits the phone, or morph in such a way that the phone harmlessly slides to the floor, her choice.


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

[User]
[The Boys] Do Marvel and DC comics exist in the boys universe?

Would be funny seeing someone say Superman is based off Homelander.

[Assistant]
Its likely that they both existed at some point. The earliest real point of divergence in both the comics and the show is 1944, when Vought deploys their first super-squad in World War II (with dramatically different outcomes). Marvel and DC (or more accurately, Timely Comics and National Allied Publications) had both started publishing superhero comics before 1940.

However, it's clear that in both continuities, Vought is really the only game in town when it comes to superhero media. Comic shops in the comic continuity are dominated by the Vought-owned Victory Comics, and in the show, Vought is the only producer of superhero movies and merchandise. In any case, it's safe to say that Captain America and Superman are about as relevant as the Fin and Green Lama: long-forgotten characters only remembered by the most hardcore of Golden Age comics fans.


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

[User] Why does something straight, like ribbon or hair, curl when you drag scissors along its surface?

[Assistant]
With ribbon this happens when you hold a ribbon taut and drag a sharp object along the surface of the ribbon. The pressure exerted by the sharp object forms a shallow depression in the ribbon, and since the inner surface of any concave curve is shorter than the outer surface of the curve, the ribbon stretches more on the outer surface than the inner surface.

This doesn't work as well when you attempt it with the ribbon on a flat surface because the ribbon is less able to form a depression. It also doesn't work when you attempt it with many other materials because they're unable to undergo plastic deformation (deformation in which the material doesn't return to its original shape).


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

[User]
Why companies can't chemical ananalyze, for example, Pepsi, and produce identical mixture on their own?

I believe some things are patented out - but then are not a secret. For example WD-40 oil is not patented and its recipe is secret, why people just don't analyze it's contents to produce a copy and gain huge cash?

[Assistant]
Well there is no machine that you can pop a sample of something into and get out it's chemical composition. Qualitative analysis (the process of finding out what a sample of something is made of) is a long and difficult process that is normally very specific to the material you are looking at. Not only that but this process would only tell you what exists in the sample, not any manufacturing techniques used to create the sample.

And brands like WD-40 use their reputations just as much, if not more, than their actual product to make money. Even if someone was able to recreate WD-40 it would not sell **nearly** as much as the same product just with a WD-40 label.

AND most of the time competing companies do not want the secret formula to their competitors products. For example Pepsi was offered the formula to Coke-a-Cola multiple times and turned it down every single time instead turning over the people who offered to sell the information to the FBI and Coke-a-Cola.

Edit: Unrelated but Pepsi is actually the tastier product according to a double blind taste test done in the 70s. Coke-a-Cola still out sells Pepsi mostly due to branding and reputation.


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

[User]
[Rick and Morty] isn't it a bad idea, as an assassin, to hand out business cards that tell people exactly where you are?

so in s2e2, the assassin "krombopulos michael" gives morty his business card that contains a real time map of where he is. isn't this kind of a real bad idea? i mean i'm no assassin but i wouldn't want my exact location to be public knowledge, especially when i'm out trying to assassinate people, and it does end up getting him killed.

[Assistant]
Depends on how good you are.  If you're so good your target can know you're coming and you'll still get the job done clean then it's good to get your name out there.  If potential clients know about your exploits then you can charge far more for your services.

Furthermore, Krombopulous Michael just *loves* killing.  Getting his name out there makes it far more likely somebody will find out about him and pay him to do what he loves.


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

[User] ELI5: how do window air conditioners (units that are not central but not mobile) keep on giving cold goodness without any kind of refill or coolant? Will it ever run out of coolness?

[Assistant]
I don't think you understand how air conditioners work, based off the nature of your question. Coolant doesn't supply coolness like gasoline supplies energy.

Air conditioning works by compressing the coolant gas until it becomes a liquid. This compression creates heat which is radiated away into the outside air by the fan blowing outside air over the coil. The compressed liquid is then pumped "inside" the house into an evaporator coil. This allows the liquid refrigerant to convert back to a gas. As this phase change occurs, heat is absorbed from the surrounding air, which is usually inside air circulated over the evaporating coil. This cools down the air being passed over the coil. That cool air is then blown into the inside of the house as air conditioning. The refrigerant is then pumped into the outside portion of the air conditioner to be compressed.

In essence, heat is created by compression and dissipated with outside air. When the refrigerant evaporates, it absorbs a similar amount of heat, which cools the inside air that is circulated through the house.  The only thing that gets consumed is energy that drives the compressor and the fans that circulate air. Since the coolant travels in a closed loop, there is no need to refill unless there is a leak.


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

[User]
Is it more efficient to boil cold tap water or to wait for hot water to start running out of the tap and then boil that?

So I imagine the two competitors here are the efficiency of my gas stove vs. the efficiency of my hot water boiler? Maybe they're not that different (both run on gas) - if so, is there a cost difference?

If they're the same, the obvious loss of efficiency comes from the cold water I waste while waiting for hot water to run - right?

***TL;DR: Thanks for the responses! It seems almost unanimous that drinking hot tap water is a health risk for a couple good reasons, although it will be faster to boil. But in regards to the original question, I agree with many others now that a real dive into the energy use and water waste numbers would be difficult and time consuming. Boil cold water, yes?***

[Assistant] Regardless of efficiency, it is safer to take cold water and boil it. Hot water allows for more things to be dissolved in it, and depending on your pipes, you could be increasing intake of unwanted substances.


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

[User]
ELI5 - Grandfather clocks, what keeps the pendulum and weight from losing momentum?

I've been looking into how they work over the past few days and I just can't wrap my head around why the weight and pendulum don't slow down. They seem to go against how I understand the laws of physics.

[Assistant] The weight is slowly pulled down by gravity, through a mechanism that gives the pendulum a tiny push on each swing to keep it going. Once a day or so, the weight needs to be lifted up to the top again, or else the clock stops when the weight hits the bottom and stops boosting the pendulum. So it's actually human muscle powering the clock, we just use the raised weight to store this energy (as gravitational potential energy) and slowly release it to power the clock.


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

[User]
[Real Time Strategy Games] Where exactly is the Player or "Commander" supposed to be?

In games like World In Conflict the player is implied to be among the men that are fighting on the map, but where exactly are they? Are they the ones leading the charge or are they just hanging back and ordering their men from a safe distance?

[Assistant]
It really depends on the context of the conflict and the exact circumstances/technology used by the faction in question. Most of the time, however, the "commander" is usually away from the field in a safe location so they can direct their forces without worry of an attack on their position. The various commanders of GDI and the Brotherhood of Nod throughout the decades famously use an Electronic Video Agent to communicate with their forces from far away. In another universe, the Allied and Soviet commanders speak through their assistants/lieutenants, who in turn report their results to the commander.

On the other hand, Jim Raynor was right there with his raiders during his fights, as were Kerrigan and Artanis.


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

[User]
ELI5: Why is it okay for IV drips to have air bubbles running through the lines?

I've always heard of the horrendous things that happen if air gets in the veins. What's the safe guard here? I about freaked out last time I had an IV because I saw air bubbles running towards my hand. The nurse just said, "nah, that's fine."

* To clarify: I saw large gaps of air in the IV line throughout the time I was hooked up to it. I'm sure I'm fine as this was almost a year ago, but out of curiosity I've done a bit of research and keep finding contradictory reports. One side seems to believe that a bit of air through an IV won't kill anybody so it's completely fine. The other, claims that it still does damage to certain cells and systems of the body, and there's no reason for air bubbles to be in the lines in the first place. They claim it's a product of lazy medical practice and it should really stop. I, on the other hand, am a landscaper, machinist, and gunsmith in training, who can't understand half of what either side is saying, hence the ELI5.

*I just can't type today. Anymore typos in this awfully written post will just have to be ignored. I'm not usually illiterate I promise.

[Assistant] RN here. There are two main types of IV lines. Peripheral IVs and central lines. Peripheral IVs are typically inserted into a small vein of the arm or hand and have a tiny diameter. This is what most people think of as an IV. Central lines (google PICC ) have a much larger diameter and are inserted in larger veins and terminate in one of the body's large vessels -e.g Superior Vena Cava very close to the heart. The real danger of air in the circulatory system is that if a bubble is large enough and makes it to the brain it can cause a blockage called an embolism in one of the smaller vessels supplying blood to the brain. This would essentially cause a stroke. A small amount of air passing (<10ml-about the size of a test tube from HS chemistry) passing through a peripheral IV just simply can't form a large enough bubble to pose a danger. In fact it has been estimated that you would need as much as 100ml of air pushed through a peripheral IV to do harm. Those tiny bubbles just get dissolved in your blood very quickly. A central line however is a much different situation. Because they have a much larger diameter and are placed in larger vessels with larger volumes of blood then it doesn't take much air for a large bubble to form. A few tiny bubbles of air that you would typically see in IV tubing is not likely to do any harm but as little as 2-3ml air pushed in all at once with a medication for instance could easily be dangerous in a central line. That's why nurses trained to clear all the air from syringes used for central lines.  It all about how big of  bubble can form in your blood. So if you have peripheral IV in your arm or hand and you see a few bubbles in your IV tubing don't let it concern you it's just not enough to hurt you.


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

[User] Why isn't there a general formula for solving quintic polynomials like there is for quadratics, cubics and quartics?

[Assistant]
The question really shouldn't be "Why isn't there a 'Quintic Formula'?", the question should be "Why is are there Quartic, Cubic and Quadratic Formulas?" Because, if you think about it, it really doesn't make much sense that there should be such formulas. What's happening is you are taking a single class of really simple polynomials, those of the form x^(n)-a=0, and saying that *any* polynomial of degree n can be written using nothing more than the roots to this single, very simple class of roots. Why should we expect to be able to solve something complicated like x^(4)-13x^(3)+9x^(2)+3x+1=0 using nothing but solutions to equations like x^(2)-A=0, x^(3)-B=0 and x^(4)-C=0? These equations are so much simpler than the equation we're actually trying to solve that it's kinda crazy to think that we can do it. Sure, you might be able to do it up to a point, but eventually the complicatedness will catch up and we'll be unable to solve them. This is the heuristic that you should have when thinking about solutions to polynomials.

Of course, there are deep reasons why 5 in particular is the first that is "too complicated", but these really only make sense with specialized math training. What happens is that to solve something with roots, we create a ladder to the solution where each step is a simple step that only requires a solution to x^(n)-A=0. The key is that we know what such ladders look like, and the ladder you'd need in order  to solve an arbitrary degree 5 polynomials is provably more complicated than the ladders you can construct using only roots. That is, x^(n)-A create simple steps, but in general you need giant leaps to solve arbitrary equations. The intuition that the gap between 4 and 5 is too big is actually not far off from what is really happening and really is the important thing to focus on.

**TL;DR**  The important thing is our heuristic that says that at some point the equations get too hard to solve, and so it becomes only a question of when.


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

[User]
When to mention/not mention that I want a position partly due to its location?

I'm writing cover letters. In addition to touting my qualifications and experience, for what types of jobs should I mention that the area has specific appeal to me, either because of family proximity or something else?

My understanding is that an R1 TT job does not want to hear this, but that smaller teaching school might. What about a medical research job?

[Assistant] I cant speak for R1 schools or medical gigs, but speaking as someone who has served on and chaired search committees, knowing you have family nearby means you might be more inclined to stay in the position, which is a plus. Id rather hire someone who is looking to put down roots than someone who sees the position as a stepping stone to something better, meaning another search for the same position in the near future.


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

[User]
CMV: When making macaroni and cheese, it's better to mix the cheese ingredients into the cooked/strained noodles rather than mix them in the empty pot, then add the noodles

This has been a point of heated debate between my wife and I.  I think that it's better to strain the noodles, put them back into the pot, then add the butter, milk, and cheese powder on top of the noodles before mixing.  I do this because the heat from the noodles quickly melts the butter and all the noodles are coated with the cheese mixture as it's mixed during stirring.

My wife's preferred method is to strain the noodles and leave them in the strainer.  Meanwhile, she adds the butter, milk and cheese powder to the empty pot and mixes a cheese sauce.  Once it's mixed, she adds the noodles to coat.    This is preposterous and it makes me sick to think I share a bed with such a creature, but there it is.  I'm afraid my 4 year old son will pick up her bad habits and one day lose a relationship due to his ridiculous mac & cheese making methods.

BUT, I'm open to having my mind changed.  Is it better to mix the cheese sauce in the empty pot?  I feel like it takes longer for the butter to melt, putting precious addition seconds in between myself and delicious macaroni and cheese.  Change my view!

[Assistant] I tend to do it your way for convenience, but the risk is when you put the powder in, it clumps inside the noodles and then doesn't mix fully with the milk and butter. If you do it in a separate pot, its easier to get a nice consistent sauce that you can then mix in with the pasta more evenly.


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

[User]
[Avatar] Is it possible to glassbend?

So it's been shown that it is possible to bend sand. When sand is melted, it becomes glass, but it's still made of the same stuff that sand is. It's a molecular change somewhat similar to the difference between water and ice.

So could a sufficiently talented earthbender bend glass? Could they, say, take the glass, grind it into powder, and bend glass powder like sand, but much deadlier?

[Assistant]
I would think that they can. Much like how Earth Benders can become Metal Benders, or even Lava Benders, it follows that they should be able to bend Glass.  And even thought glass in solid form is more brittle than metal, I'd bet that Glass Benders could reshape glass to fit there needs.

It's be interesting to see how they fight with that ability.


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

[User]
[King of the Hill] Was Dales Dead Bug a successful business?

So its established that Nancy is the breadwinner of the Gribble household and she actually gives Dale money. But was Dale profitable at all in his own ventures? Did his extermination business ever make him good money?

What about his bounty hunting services?

[Assistant]
I think at one point Nancy says that Dales business pays the cable bill.

Per Google, an average pest control tech in Texas makes anywhere from $20k-50k annually. Although Dale owns the business, hes also the sole employee, so he probably makes the lower end of that figure after overhead.

That being said, Dale also purchases a lot of weird items that Nancy most likely doesnt approve of, so its possible that Dale makes decent money and just spends it poorly without her full knowledge.


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

[User]
How large must a man-made structure be in order for weather phenomenon to occur inside?

When I say "man-made structure", I mean a large wide, but closed off building like incredibly large greenhouses or something. How large would it be for weather like wind, rain, clouds, or fog be able to appear inside? And I'm talking about it occurring naturally on it's own accord, I'm pretty sure that it would be possible for people to facilitate weather to occur in it through artificial means.

[Assistant] Not that large. Rain clouds have been known to form inside the Vehicle Assembly Building at the Kennedy Space Center. The VAB is a large building, but it's not incomprehensibly large or anything. There are half a dozen or so buildings that have more internal volume.


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

[User]
If a bird is inside a box, but it's flying, does the box weigh the same as it would if the bird was standing on the bottom.

I was staying with one of my buddies at his grandmothers house for a few days, and somehow we got onto this question.

To me and my buddy, it seemed simple. If the bird is flying the box would weigh less because the weight of the bird is being supported by the bird itself so it's not combined with the weight of the box.

[Assistant]
If the box is closed (no air coming in or out) then the box will weigh the same on average regardless of whether the bird is flying. Over a long period of time, the average acceleration (averaged over time) of all the mass in the box (bird, air, and box) is zero, which means that the forces sum to zero (averaged over time). The forces are the supporting force from your hand and the force of gravity on all the mass in the box. Therefore, the force you're applying to the box is equal in magnitude (averaged over time) to the force of gravity on everything in the box (including the bird).

One way to make sense of this is to remember that birds (and airplanes and helicopters) fly by pushing air down. If the air can't go down through the floor of the box, then the floor of the box must stop that air. On average, this force applied to the air by the box is the same magnitude as the force applied from the bird to the air (which is the weight of the bird).


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

[User]
[General] A lot of individuals with enhanced durability seem to share a vulnerability to piercing damage. Has there ever been anybody who is immune to piercing , but is vulnerable to blunt damage?

E.g. Stabbing, bullets etc. have little/no effect on them, but punching could do a lot of damage.

[Assistant] Luke Cage has this issue, especially in the MCU. He's gut impervious skin which can't be damaged... but blunt force can still harm him. He got in trouble in the first series of Jessica Jones because of a brain haemorrhage and the normal treatment of drilling a hole in his skull wouldn't work since his scalp couldn't be opened, so they went through his eye instead.


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

[User]
[Fallout] Did bicycles ever get invented?

Playing through NV and I realized, a bike would probably the best way to get around the wasteland. If it hasn't been invented yet, someone should really get to it, they'd be drowning in caps in no time.

[Assistant] In the rugged, jagged, cracked, often mountainous Mojave wasteland, you think a bicycle would get you anywhere? It'd be worthless! The few places that you could actually use it, it'd be hard enough going that you might as well just walk.


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

[User]
How effective would a Shotgun be against a Jedi?

Whenever Jedi's go up against blasters, etc, they always effortlessly deflect the shots. How would they do when faced with a shotgun, or whatever the Star Wars equivalent would be?

[Assistant] A shotgun or flechette launcher is somewhat more effective than a blaster against Jedi, but Jedi can still easily dodge the shots with force-enhanced speed or simply stop the projectiles with the force. Area effect weapons, such as mines or rocket launchers, or massed blaster fire generally work better against Jedi.


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

[User] [Malcolm in the Middle] Is Lois a good mum?

[Assistant]
The debate of whether Lois is a good mother or not is a tough one to have.

Her background shows that she tried being a conventional mother who showers her child with love and care. Something inside of her snapped and she became the Lois we've come to know. When you take this into consideration, then you understand that, at the very least, she did attempt to be the ideal mother. Unfortunately for Lois, for some reason not entirely explainable (probably the big brother-little brother effect that started with Francis), her kids have a tendency to do way worse than your typical child. Francis was wildly destructive (Destroying the house, blowing up a car, incidentally cutting off Spangler's other hand). Reese's stupidity gets him in very convoluted messes. Malcolm's ego, combined with his genius, can lead him to rebel to extremes. Dewey's luck+genius+charisma took him cross country at one point.

Needless to say, while she often employs unorthodox techniques and goes as far as controlling her children's future, it's fair to assume that she is the best mother possible for containing their calamity. In the show, you notice that whenever Lois is not explicitly around or keeping her eye on them, they end up in bigger messes than ever before.

Plus, y'know, Hal is kinda inept.


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

[User]
Are black holes really holes?

From what I've gathered about these phenomena, they seem to me to be incredibly dense regions of space, like giant, planet-sized magnets. Are they really *spheres* of such great density and gravitational-pull that we simply cannot see their "surface?" I know they are of such uniqueness that terminology can be hard to accurately apply, but if they truly were holes, wouldn't they have to have "empty" somewhere?

[Assistant] They're "holes" in a metaphorical but important sense. A black hole is an object of such great density that, near it, gravity is so strong that, quite literally, there are no trajectories that move away from it. (This is commonly said as "even light cannot escape", but IMO that doesn't capture the really fundamental character of the geometric constraint well.) Thus, if you think of spacetime in terms of paths through it, a black hole really *is* a 'hole": paths can go in, but they can't come out.


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

[User] ELI5: How are crowds counted (at non-ticketed events, like protests and riots)? How do they figure 20 or 50 thousand people showed up for a non-organized event?

[Assistant] They divide the total area occupied by people into small parts. They count the number of people in a few parts, average that, and multiply by the number of parts they made. The more small parts you add to your average, the more accurate your number will be.


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

[User] [Batman] What health issues plague Batman due to his constant lack of sleep, stress, and habits?

[Assistant] Seemingly none. Despite having approximately 3 hours of sleep or less a day, the stress of running THE biggest mega corporation in human history, constantly getting injured to the point of needing stitches and casts, and engaging in strenuous activity on par with a truly committed world class athlete he seems to chug away just fine in most continuities of his story. In the Batman Beyond story line the only thing that actually ended up stopping him was aging, some thugs got the drop on him with a crowbar and he picked up a gun in desperation sending the hardened criminal into a nervous break down at which point Bruce hung up the cape accepting he could no longer do the job anymore.


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

[User] [Harry Potter] Does Hogwarts have a sex ed class? If so, what do they teach differently than a muggle class?

[Assistant]
They don't teach a sex-ed class. Anything required to know about sex is up to the parents for the children.

Sexuality in the wizarding world is a lot different than the muggle world. Magic would be the ultimate 100% birth control and there is no gender inequality among wizards.


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

[User]
[DC/The Boys] What if Homelander was raised by the Kents?

Would he have ended up like Superman, a beacon of hope and inspiration? What if he had Superman as an older brother (or better yet, younger brother)? Or if he had been rescued at a young age?

[Assistant]
Homelander would have turned out a decent human being if he was raised by a good family like the Kents.

But he would not have been Superman. One of the main points of the show/comics is the Herculean force of will it would take to maintain the moral purity of Superman, if a person actually had all of Superman's power. Not only would it be difficult to remain ethical when you can do so many unethical things without getting caught, it would also be incredibly hard to raise a child to be a moral paragon when they can do the things Homelander can.

How would the Kents punish a hormonal teenage Homelander for peeping, when they would have no real way of telling when he was peeping at all? How would they discipline a toddler or kindergartner with the power to kill them with a single a blow? How would they defuse temper tantrums when getting split in half by an involuntary laser beam is a valid concern?

Homelander would still end up slightly messed up, just by the virtue of having his powers. That's one of the core ideas of The Boys. But he would still be a much better person than he is in the main canon universe if he was raised by good, moral parents who actually loved him.


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

[User]
ELI5: How are software engineers objectively measured when problems span such large difficulty ranges and there are multiple ways to implement solutions?

Always been curious how "workload" is assigned and estimated for software engineers.

[Assistant]
That's a problem no one has really solved yet.
The way it usually works is that you break down big tasks in more manageable sub-tasks. Then you estimate how long each sub task is going to take, based on how long similiar sub-task took in the past, add up all the sub-tasks, then add some allowance for tasks taking longer than estimated, then add some more, and finally you have a number that you can tell your manager.

If you have a team of people you generally know who works faster or slower and assign them a corresponding amount of work.

With a bit of experience it works reasonably well.


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

[User] ELI5: How is YouTube able to store so many videos?

[Assistant]
on you computer you can put, let's say 1000 videos. Now if you buy some extra (external) harddrives you can make this 5000. But now you don't have any place on your pc to add new drives and a little tool for accessing the pc from a remote location. So you decide to remove everything from your computer except the harddrives with the movies and buy a new pc for accessing this one. Your old computer has now become a server.

Now get 100000 of these servers and connect them with each other (internet) and you can store many videos.


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

[User] ELI5 This might be a dumb question but it just started raining, so I started thinking, why does it start raining slow then increase in speed? Like what is happening in the cloud that's different than before, or vice versa if it starts pouring like there's no tomorrow then slows down?

[Assistant]
The cloud moves.

First, the cloud's (thinner) edge comes over you, and because it's thinner there's less rain to unload; then the bulk of the cloud, then finally the trailing edge.

Clouds are water vapor suspended in air (and so is fog), and the ability of air to keep water depends on temperature and pressure.  Air is always moving up there, and at some point the air that contains a cloud may hit colder air or different pressure air, and the cloud will start unloading.

But it keeps moving; air keeps moving it along.

So, more rain vs. less rain depends on the thickness of the part of the cloud that happens to be passing above you at any point in time.


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

[User] ELI5: How does a 25cent package of dried out, lifeless seeds grow into an alive, green sprout simply by putting them in some soil and adding water & a light source?

[Assistant]
Well first, seeds aren't dead, even if they seem dried out like a dead leaf. The seed contains what is essentially an embryo, the next generation of plant. When the seed is planted and takes up water, referred to as imbibation, it commences germination; this process is completed when the embryonic root visibly emerges from the outer structure of the seed. Thereafter, there is the establishment of the seedling which utilizes reserves stored within the seed, which is then followed by vegetative and reproductive growth of the plant, supported by photosyntheses.

Seeds metabolically inactive (quiescent) in the dry state, which allows them to withstand extremes of drought and cold. You can store a seed in liquid nitrogen without harm. Upon the imbibition of the seed, metabolism commences as water enters the cells, using enzymes and structural components present in the dry seed. Respiration to provide energy has been observed within minutes of water uptake. Mitochondria, initally inefficient because of damage sustained during druing and rehydration, are also involved. They repair during germination, and new organelles are synthesized. Protein synthesis also commences quite rapidly in the imbibing seed. Stored messenger RNAs (mRNAs) are used as templates for protein synthesis in very early germination, and later they're replaced with newly transcribed messages. Elongation of the cells of the radicle (embryonic root) is what is responsible for it emerging from the seed.

Some seeds are in a state of dormancy and need certain environmental stimuli to break the dormancy. Sunlight, low temperatures (33-48 degrees F) for several weeks, day/night fluctuating temperatures, and chemicals such as nitrate in the soil or applied hormones (gibberellins) in the lab, and fire. Lilacs, for example, only thrive in areas where there are winter months of cold temperatures, and day/night fluctuating temps (like here in Minnesota, where lilacs are very common). They disperse seeds but they cannot germinate and so lay dormant until after being subjected to the cold of winter, and the conditions cause the parent plant to wither, eliminating the competition for space and nutrients when the weather warms.


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

[User] Why does your nose run when eating something spicy?

[Assistant]
Gustatory rhinitis affects many people after they eat hot or spicy foods. When a person eats these foods, a nerve called the trigeminal sensory nerve is stimulated, which causes the nose to run. A person may prevent gustatory rhinitis by avoiding trigger foods.

Release of histamine, a nonspecific immunity mechanism to external stimulus.


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

[User]
Can we get information from outside of the Observable Universe by observing gravity's effect on stars that are on the edge of the Observable Universe?

For instance, could we take the expected movement of a star (that's near the edge of the observable universe) based on the stars around it, and compare that with its actual movement, and thus gain some knowledge about what lies beyond the edge?

If this is possible, wouldn't it violate the speed of information?

[Assistant]
Most likely not.

The speed in which changes in gravitational field propagate is finite and also apparently equal to the speed of light. Recent successes with gravitational wave detection by projects like LIGO support this claim. So if an object outside of our observable universe were to "propagate" their gravitational influence to the star we can see, and then the image of that star affected by gravity propagate to us it would take at least the same amount of time it would have taken the signal from "unobservable" object to reach us directly.


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

[User] When I, as someone living in Australia, spend money to a Twitch streamer in America, does it get counted in the national import export statistics?

[Assistant]
Conceptually, yes. As part of service imports on the Australian account, and as part of service exports on the American account.

Whether or not actual GDP statistics measure this accurately is another question. Probably they do if you pay through Twitch itself.


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

[User]
[Pokemon] Why don't some pokemon appear next to each other on the National Pokedex when they evolve to those ones

Like Pichu and Pikachu?

[Assistant] Oak made the first Pokedex before he was aware of breeding. As such, he had never seen a Pichu, and it didn't go into the Pokdex. Later, he found out about new Pokmon that were related to the old ones. He couldn't add entries into the middle for backwards compatibility reasons (Mewtwo is 150* ^^i ^^can ^^count ^^ssshh, and it's never going to be 152, or else old models of the dex will be really confused when they communicate with newer versions). This leaves the only spot to put "new" Pokmon at the end. Regional Pokdexes have evolution lines in a reasonable order, since they are able to catalogue everything we're aware of all at once, starting at #1.


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

[User]
[Star Wars] How is it that General Grievous had such a mobile and functional armor for his sustenance, yet Vader had a bulky, inconvenient one?

From what I recall, Grievous only had his head and heart as functioning organs, yet his armor allowed him to best multiple Jedi and even throw off Obi Wan for a while. Those 4 handed arms, the sheer flexibility of his droid body made him almost equal (if not better) then some Jedi who are trained in the force.

Why then was Vader given such a hulking heavy armor? Surely injuries like Vader's weren't as bad as Grievous'? Plus wasn't Vader supposed to carry out searching and killing other Jedi? How did Palpatine expect him to do that? I mean, yeah Vader proves us that he doesn't NEED a body like Grievous', but still, why choose to limit yourself when you can be a faster, more efficient killer in the battlefield?

More weird is the fact that Vader himself never tries to upgrade his suit. Doesn't he remember from his clone war days about the droids and other cool tech that can benefit him? Hell he was a mechanic/engineer building pod racers and droids as a kid, doesn't he ever think "gee, maybe I should get a better armor"?

[Assistant] Vader was strong and durable, grievous was fast and agile. vader was a tank, grievous was a assasin. In the comics, vader meets a guy that has the same sort of cybernetics as grievous, and he easily beats him. sure, vader cant run fast, but he doesnt need too. he is slow, but unstoppable and unkillable.


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

[User] [The Forever War] How are so many people convinced to go to war? If you aren't killed, by the time you return your life, as it was, is over anyway... I don't see the benefits..

[Assistant]
People are willing to give a lot when *the survival of the entire species* seems to be on the line.

And, thanks to technology, it was a surprisingly low-personnel war, all things considered. A few million troops & crews, maybe, all told, over the course of a millennia? That's peanuts comparatively.


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

[User]
ELI5: Could the dragonfly copters from Dune work in real life? Would they be better or worse than existing helicopter designs?

I was blown away by these in the movie. They looked amazing but I know nothing about the science involved in flight and how realistic they actually were.

[Assistant]
Flapping wing flying vehicles are called "ornithopters". There's no technical reason they can't work (it's the same physics as birds and bugs), but they're \*really\* hard to do well or efficiently in a mechanical design.

Flapping is a great action for push-pull mechanisms like muscles but sucks for rotating machinery (all our high-power output engines put out rotation). It is also a highly complex integrated control problem...the kind of things that brains are great at but very difficult for human-designed electronic controllers.

Propellers, like a helicopter, are very efficient. Animals, other than some very obscure microscopic sea life, can't do rotary joints so propellers and motors were never an evolutionary option. Wings are a great solution \*if you can't have propellers or bearings\*.


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

[User]
ELI5: How can the weather be below freezing AND 100% humidity?

Doesnt the temperature mean that fog can't be "humidity"?

Isn't humidity moisture and doesn't moisture crystallize into a solid form below 32 degrees?

[Assistant] There are two forms of humidity: relative humidity (%) and absolute humidity (grams of water/liter of gas). Something that is at 100% humidity means that it is holding as much water as possible, no matter how little that may be.


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

[User]
ELI5 why I would want to use a credit card instead of a debit card.

I think I understand the basics but I'd like to confirm what I think I know.
Update: thanks for the wealth of advice. I think the most compelling reasons boil down to:

1) boosting my credit score which is useful for other credit cards and loans and such.

2) Perks from credit card companies that make using them more worthwhile (ie sky miles, points etc)

These benefits are contingent on being a responsible credit card user and paying your bill in full monthly.

[Assistant]
Let's say your favorite candy store had three prices on everything: one price for people paying with debit cards, one price for responsible people with credit cards, and one price for irresponsible people with credit cards.

Your favorite candy is $1 for debit card people, $1.14 for the irresponsible kids, and $.99 for the responsible credit card users.  It might not be a big difference, but you realize that since you eat hundreds if not thousands of these candies a year, the savings add up over time.

The reason for this is that when you're irresponsible with your credit card you build up debt and that candy you bought will wind up costing you more.  Debit cards are like paying with cash you have, so that's no difference.  However some credit cards will give you rewards in the form of points or cash back that usually comes out to 1%.

Yes, the irresponsible person is also getting points but it's a drop in a bucket compared to the debt they're racking up.  However the responsible candy-buyer is paying his candy tab every month and after buying 1k candies finds he can get 10 free candies via the points he accumulated.


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

[User]
[Harry Potter] Why doesnt Hogwarts have an Arts Department?

All of the courses at Hogwarts seem to be practical and functional. **Defense Against the Dark Arts**, **Transfiguration**, **Potions**, and such. Im aware that, in the movies, there appears to be a choir, but it seems thats less of a class and more of an extracurricular; plus, its only seen in one or two scenes.

Why doesnt Hogwarts have classes in **Photography** (which is closer to Muggle Filmography than Photography), **Dance**, or **Creative Writing**?

[Assistant]
Hogwarts is a vocational school. The purpose of the school is to teach you to be a competent wizard (but not TOO competent, hence the Restricted Section).

You have freedom in what classes you choose, but ultimately if it wont help you be a wizard its not worth teaching.


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

[User] ELI5: how do laser pointed thermometer guns find a reading of the temperature?

[Assistant] The laser is just there so you know where the reading is being taken from.  Everything emits infrared radiation as long as it's above absolute zero and if it gets hot enough it starts emitting visible light.  The radiation things normally emit based on their temperature is a form of light below what the human eye can see unless it gets intensely hot.  The laser thermometer is able to sense this radiation and determine temperature based on how strong and what "color" the light is.


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

[User]
What Obama Just Said, Explained

We reached a budget deal, so we're not gonna default (meaning our economy is hopefully going to be ok). The agreement had 2 parts-
1. A trillion dollar in budget cuts over 10 years. Our government will be spending less, which will help our debt problems.
2. A committee will be made which needs to plan more cuts by November. None of the drastic thing the parties wanted- taxing the rich for democrats, and cuts to entitlements for republicans-have been made yet. The parties and the president hope the committee will decide to do these things.
Hope this helps!

Glossary-
A default would mean our government wouldn't be able to pay it's debts. This would make investors feel like we wouldn't be able to pay them, and would pull out, which would be bad for our economy.
Entitlements are government programs like Medicare or social security- when the government gives money to people/pays things for them (including when citizens pay for it gradually throughout their lives)

[Assistant]
"Our government will be spending less"

We should include here that Keynesian economics recommend *increasing* spending in a recession.  So while we will be helping lessen our debt, this might not be the best time to do so.


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

[User]
[Marvel] What if Magneto's family escaped the Holocaust?

Magnetos's family escapes from Poland and is never sent to a concentration camp. They manage to stay safe during the entire war.

How does this change his life? Does he still awaken his powers? Does he join Xavier?

[Assistant] He still awakens his powers, albeit probably a bit less powerful.  He still sees the worst in humanity, but due to not living it personally he has a bit less of a visceral reaction to it.  We end up with mostly the same Magneto, but slightly softer and more receptive to reason.


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

[User]
[The Boys (show version)] Why does Homelander have fillings in his teeth?

How does an indestructible man get cavities?  And what kind of heavy duty equipment did Vought use to drill his teeth?

[Assistant]
In the comics, Homelander's powers manifested in-womb, and he was superhuman from the moment of birth (>!quite horrifically, as is the rule with Homelander.!<). There would be no way for comics Homelander to develop tooth decay.

In the TV series, it seems that powers don't tend to manifest until puberty; the child with plasma beam vision in the first season was an anomaly, not the rule.

So Homelander was probably born more or less normal, or at least not at the peak of his powers, and Baby Homelander's teeth were just as vulnerable to cavities as any human. It wasn't until he grew older that his powers manifested more completely.


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

[User] Why does paper stay folded once you fold or wrinkle it? And since placing heavy objects on paper can help smooth it out, how much force would you have to apply to a creased sheet of paper to make it completely "smooth" again?

[Assistant]
Imagine what paper looks like on a microscopic level. It's basically a bunch of cellulose fibers woven together. For the purposes of argument, let's imagine we have a gigantic piece of paper, and instead of fibers, we have sticks.

When you fold that giant paper, some of the sticks at the fold point are going to break. The harder you fold, the more sticks break. Not all of the sticks break; some bend, enough that the paper can stay intact. Even if you straighten out the giant paper though, some sticks remain broken.

This is what happens when you fold paper. You are actually weakening the structural integrity of the paper. You make breaks in some of the fibers, we while some just bend or twist. The ones that break are permanently broken.


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

[User]
ELI5: How does mental fatigue work?

Something like when you are doing a really hard and long test or just learning too many things at once and your mind just stop out of nowhere.

[Assistant]
A popular hypothesis these days is that your brain runs out of the neurotransmitters that your brain cells use to talk to each other. When you rest (e.g., sleep), your brain cells have time to make more. Caffeine, amphetamines, and other stimulating drugs work by promoting these transmitters.

Also, your brain runs almost exclusively on sugar (unless you are starving/on a keto diet). So if your blood sugar is low, your brain feels tired because it doesn't have enough fuel to work properly. So eating a little candy or drinking a little bit of a sugary drink can help perk your brain back up.


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

[User]
Why is academia such bullshit?

I'll save you all a long rant. I just don't understand why the culture of academia is so toxic. The writing clogged with jargon. The jobs scarce.

Why did academia become so soul-crushing?

[Assistant]
More soul-crushing than coal mining?  Than waitressing?   Than factory work?   More soul crushing than being a novelist who can't publish?  A secretary bored out of her mind?  An insurance salesman who could have been contender?

I think we overdramatize.   There's no more jargon here than there is at, say Google.   The job market is indeed tight, but so is the job market in professional football, in painting, and for calligraphers.   If you don't like it, you don't like it.  But it's not the worst thing ever.   The work is clean and you get to sit down, at least.


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

[User] [The Dark Knight Rises] What did investigators make of the plane crash in which the wings fell off and then the plane continued another 50 miles before crashing?

[Assistant] They might conclude it was an act of sabotage, maybe even direct terrorism, which they'd consider anyway considering who the passenger was. But that doesn't matter- all that matters is that it's believed everyone aboard, including the Shadow assassin and Dr. Pavel, had died.


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

[User]
ELI5: Why brand name drugs are so much more expensive than generics

I understand that drug companies get a period of time where only they can produce that drug, and they concentrate on making as much money as possible before the patent expires. However, in the time that they are the only game in town, wouldn't they get more efficient at producing the compound?

Why don't they try to compete in terms of price after the patent expires?

[Assistant]
Producing the drug efficiently is irrelevent for a lot of drug companies.  In fact, there are lots of drugs where a single bottle of the medicine contains under a dollar's worth of the active ingredient.  Rather, drug companies try to make up for other costs.  For example, drug companies must pay the scientists who look for new medicinal ingredients.  On top of that, every drug must undergo testing to be approved by the Food and Drug Administration.  Almost all of the drugs that are tested are rejected at this stage.  As a result, for every 100 drugs the company must design and pay for, 1 will get approved and become profitable.

So, where do generics come into the picture?  Pretend Company A produces Drug X and gets a patent.  For the next few years, only Company A may legally sell this medicine.  However, once the patent expires, Company B can also start selling medicines containing Drug  X.  However, Company B has taken a shortcut.  Instead of spending millions of dollars to produce a drug, it just copied someone else.  As a result, Company A takes the attitude that it's doing a good thing by raising prices.  After all, their profits go toward research and developing new cures, whereas Company B really isn't innovating.  Patients buy the name-brand drug because it generally has a good reputation and a recognizable name.

TL;DR: Drug prices are related not to the price of physically producing pills, but to the expense of having to research and develop drugs.


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

[User] Why are the dwarf planets the farthest from the sun in our solar system? Is this normal in most solar systems or can a dwarf planet be the closest planet to the sun?

[Assistant]
Well, not *all* of them are that far...Ceres is a dwarf planet, and is located in the main asteroid belt between Mars and Jupiter.

In general, though, they'll be located in a region that could not form full planets. In Ceres' case, Jupiter disrupted the accretion process of any other planets near it, leaving just Ceres as the product of failed accretion. For the dwarf planets out past Neptune (Pluto, Eris, Haumea, etc.), there's simply not enough material out there, and it's spread over much too large an area for accretion to work.

I've actually heard some folks refer to Pluto as a "failed giant planet core" - it formed too little and too late to really get the required amount of rock and ice (about 5 - 10 Earth masses) to begin the runaway accretion process. Crossing that threshold allows such cores to build up lots of gas to eventually become a giant planet...but Pluto just never had enough material close enough to reach that threshold.


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

[User] [Last Airbender] You got a water bender bending vines into a giant monster why not earth benders make giant stone monsters or worse fire benders making giant lava monsters?

[Assistant]
Huu seems to need to be inside the plant monster to control it.

Earthbenders *do* cover themselves in animated stone armour, and presumably they could make it monster shaped if they wanted to, although it's mentioned that being covered in stone slows you down. This implies that yes, you do need to be inside it to make it move like a human.

Given this, trying to make a giant lava monster has...obvious flaws as a plan.


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

[User]
[General Sci-Fi] If a Immortal man committed a crime and was given a life sentence, how long would they have to serve?

So an Immortal man committed a crime and was sentenced to life in prison without parole, how long would he be locked up?

He can't die of old age and there isn't a possibility of the death sentence or another inmate attacking him so what happens to him. Does he serve the time to the age of a average man? Do they keep him imprisoned for 100 years and decide that counts as a life sentence? Or do they keep him locked up for eternity as he's Immortal and will never die in prison?

I know this isn't strictly science fiction and more of a somewhat moral question but I'm really interested to know what the rules would be surrounding someone who doesn't die.

[Assistant]
A 'Life Sentence' is not a uniform legal punishment. In some regions, it's literally the rest of your life, in others, it's anything above a particular amount of time (as low as 25 years). The former is apparently becomming less and less common, and only seems to exist in a few state in America.

So, in most places, a 'Life Sentence' constitutes a set term, say, 80 years, which makes it unlikely that the convicted party will every be released. In those circumstances, immortality would make it so you could functionally live put your sentence and then get released.

In the few alternatives... Well, you'd probably outlive the justice system.

Immortality means you can basically outlive anything but other immortals, and the Universe.


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

[User]
[Harry Potter] How did everyone know about Harry's scar?

Hagrid pulled baby Harry from the smoldering ruins of his parents' house and immediately delivered him to the care of the Dursleys. So how did his lightning bolt scar become such a widely known identifying mark?

[Assistant]
Hagrid boasted about it, drunkenly, in every pub and party from London to Hogsmeade.

Dumbledore most likely spoke to ministry officials (in a general sense) about what happened and probably mentioned the Scar.

Word gets around.


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

[User]
ELI5: How much heat does a pre-heated oven lose when you open it up to put in the food?

If I pre-heat my oven to 400 degrees, then I open it and leave it open for 10-20 seconds or so to carefully put the food in the middle of the center rack without burning myself, I can feel a mass of hot air venting out of the oven, but the electronic thermometer doesn't change. Am I actually losing a meaningful amount of heat?

If so, do the recipes that call for a very precise bake time ("32 to 34 minutes") compensate for this reality that for the first few minutes of the bake time, the oven is not at the optimal temperature?

[Assistant]
One factor not mentioned is that the sides, top, & bottom of the oven chamber, along with the rack or baking sheet you place the food atop, being solid metal will hardly give up much heat the time the door is opened to place something inside the oven.

This is the purpose of preheating, for it takes longer to heat up the metal than the small mass of air inside the oven chamber.

Which after the food is placed inside & the door is again closed, it will take little time to heat the air up again to proper temp.


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

[User]
[Bioshock Infinite] Shouldnt Booker have the ability to open Tears as well?

In Infinite, we learn that Elizabeth can open tears because her cut finger is in another dimension.

With this logic, shouldnt Booker have the ability to open tears as well since he bleeds from combat/sheds hair and skin cells in different worlds when he and Elizabeth travel to new dimensions over the course of the game? (A dimension where the Chinese guys tools are back at the shop/A dimension where Columbia is an underwater city named Rapture instead)

[Assistant]
I see it as a combination of two factors.

First, Elizabeth has had her abilities since infancy, so she has had years to practice, and her brain may have even developed in a special way that gave her more control.

Second, her injury was directly inflicted by a tear, so her nervous system was in direct contact with the space the between worlds. Though it's worth mentioning that you don't have any muscles in your fingers  so it's not a simple as saying that the motor nerve that used to control her pinkie, now controls her powers.


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

[User]
[Stranger Things 3]Why didn't This start world War three?

Dustin saying this is a "red Dawn scenario" was  played for humor but it really kind of is.
A whole Russian military instillation on (or under) US soil at the height of the cold war.

[Assistant]
Here's a secret about World War III in the 80's:

NOBODY wanted World War III. It was a guaranteed lose situation for both sides. So both governments would do a lot to prevent it. They'd argue, yell at each other, maybe make concessions, possibly start a smaller proxy war somewhere else under flimsy pretenses, but both parties would still be really motivated to find some sort of peaceful compromise.

Remember, it wasn't an "invasion" where lots of people got killed. It was spying, which both sides did, so no lines were really crossed and the cold war could still plausibly stay cold for a little while longer.


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

[User] ELI5: How did kings know how much was in their coffers and avoid having it picked at by treasurers?

[Assistant]
This is still a problem in the present day. The answer is: you have another, independent person (an auditor) come in and make a separate count. And you warn the treasurer that this is going to happen, again and again, so they'd better not cheat because they'll get caught.

For a while the Chinese Emperor forgot to do this, and when he finally announced that auditor were coming, his staff burned down the treasure storehouse because, presumably, they knew their thefts would be found out.


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

[User]
CMV: The power of magic has caused people born into the wizarding world in Harry Potter to lack critical thinking and problem solving skills.

The ability to use magic in the Harry Potter universe has allowed for creative solutions to a lot of problems that people face. However, I believe that using magic to solve problems has caused people born into the wizarding world to be unable to think through basic problems well themselves. Instead, solving a problem is just knowing the name and wand movement of a spell that will take care of things. This reliance has bled into how people navigate all situations that don't have an obvious or magical solution.

I've been going back through the entire plot, mostly by listening to the podcast Mostly Nitpicking do a full movie series run, and have noticed how a lot of characters lack what people typically consider common sense in a lot of situations. The character who does seem to know everything in every situation is one who was born and raised entirely isolated from magic, Hermione. I think a lot of what makes her studious nature so unique is that she actually wants to understand things and how to deal with unexpected circumstances while people born into magic aren't worried about figuring things out for themselves.

A real life analogy to this could be comparing a student who came from a privileged background and had others, like their parents, do things for them versus a student who didn't have this luxury and needed to do more for themselves. A student who never needed to do things on their own typically struggles more with critical thinking than their peers because they're used to having other people do that for them. In Harry Potter, those born into magic face a similar problem as a result of magic replacing the need to do many things themselves.

This seems to be most apparent with the three main characters. Ron, the only character who has relied on magic to accomplish basic tasks for his entire life, is shown to be less independent in his thinking, to have less initiative, and to look like an absolute dunce when a solution isn't obvious. Meanwhile, Harry and Hermione take initiative for themselves much more frequently and are able to reach solutions themselves. This is a small sample size admittedly, and I'm using it more as an example than as proof.

I can see how the ability to use magic to help with things can foster more creative thinking and promote problem solving skills, but I don't think that plays out in the people in the universe. Instead, magic is hamstringing most witches' and wizards' ability to think effectively for themselves.

[Assistant]
Keep in mind, the books were told from the perspective of Harry Potter.

Harry Potter learned through rote memorization, mostly, but there were underlying principles to magic that he did not understand.

This is alluded to in several places in the books.  Harry excelled in potions class using notes written in margins, written by someone who clearly understood why the potions worked enough to be able to modify them.

Professor Slughorn asked the students to customize a antidote based on the principles of potions, and Harry had no idea how to do it, but he got around it by grabbing a bezoar stone.

Hermione explains that one can not produce food out of thin air because it is one of five exceptions to Gamp's law of elemental transfiguration.  What that means, Hermione obviously knows, but Harry clearly does not.

Magic only seemed to be rote memorization, rather than derived from underlying fundamental principles, because the main perspective of the story was ignorant of those principles (which conveniently prevented Rowling from having to come up with and explain to readers hard magic rules).


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

[User] ELI5:How come our brain ( in all its power ) can very rarely recognize that its in a dream vs reality when there are no physical stimuli?

[Assistant]
Sleep is very important to us. during sleep, parts of the brain shut down - one of which is the amygdala which controls inhibitions. That makes it harder for us to discern reality from fantasy.

Another thing that happens when you sleep is that the hippocampus does a lot of memory sorting. That's when memories are encoded into your long-term memory. As you can imagine, this is *also* very important.

And that's likely why dreaming happens in the first place.

It's pretty important that this process be allowed to happen, so basically the brain puts the rest of you in Do Not Disturb mode.

It's not that the brain lacks power to know we're dreaming. On the contrary, the brain *is* powerful enough to make you not interrupt the important stuff!


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

[User]
[DC Comics] Are Kryptonian superpowers the result of genetic engineering?

In the Superman canon, it's never really explained why Kryptonians develop superpowers when in the vicinity of a yellow sun. Is it possible that Kryptonians in the past experimented on themselves to become "super" long ago in their past and just plum forgot about it by the time their planet ended(Perhaps the reason they abandoned the possibility of space colonies because they discovered how chaotic a civilization of supermen would be)? Jor-El knew that his son would develop powers in front of a yellow sun, but he was a scholar, so he probably had access to records that the normal Kryptonian citizen wouldn't.

[Assistant]
Depends which version you mean. In the Silver Age, it was - or rather, it was the result of a massive, billions-year-long eugenics project by the Guardians to create the perfect Green Lantern.

Shortly before the project came to fruition, the planet unexpectedly exploded. Unbeknownst to the Guardians, their perfect Green Lantern survived, sent by his parents to some backwater planet in Sector 2814.


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

[User]
ELI5: Why the electricity in our bodies can't power devices in our bodies (like a pacemaker).

I was thinking about this today, and I'm sure I'm not the first.

But what are the limiting factors in being able to power electric devices inside our bodies with the currents that are created naturally by our own bodies?

Do we naturally not supply enough energy or enough surplus energy? Do we not have the interface technology? Is it even theoretically possible?

Seems like it could be a gamechanger to utilize ourselves as a power source instead of needing to replace devices batteries (like a pacemaker).

[Assistant]
> But what are the limiting factors in being able to power electric devices inside our bodies with the currents that are created naturally by our own bodies?

We don't produce that much electricity + there's no interface for it.

The whole heart is a natural pacemaker with particular nodes in it that have a tendency to pace faster than the rest of it, which basically sets your normal heart rhythm. We use pacemakers when the electrical activity doesn't conduct through your heart properly or there's a risk that it might spontaneously go into a rhythm that's dangerous for your heart.

Electricity doesn't just like flow back and forth through our body, it has very directed and purposeful circuitry that serves to do certain things. It's not like we can just redirect current from some random part of our body to our heart - and even if we could - the energy used in pacemakers is much higher than what you'd normally find in your body. Plus, other than your heart, there's no natural capacity to regenerate the energy required for pacing that the pacemaker would require.

With minimally invasive surgeries today, a pacemaker can last quite a while and batteries only need to be replaced every few years in a minor surgery. They're not as large nor as problematic as they used to be in the past.


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

[User] ELI5: Why are peanuts and other nuts such a common allergen, compared to other foods?

[Assistant]
Peanuts contain many proteins that are not found in the body.

Say you are allergic to every 1/10 proteins not found in the body. Let's say fish has 3 proteins not found in the body and peanuts have 6.

Then take a group of 100 people. You will find a lot more people are allergic to peanuts as there are more proteins not in the body compared to fish.


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

[User] ELI5: Why is air colder when it's moving fast?  (fan, wind)

[Assistant]
Air is an insulator and holds warmth you generate close to your skin.

Wind blows away that insulation layer and replaces it with cooler air that has not been warmed by the heat you emit.

Or something like that.


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

[User] What causes our voice to be different when tired or just after waking up?

[Assistant]
When you sleep, fluids accumulate in the tissues of your throat,  changing the way your vocal cords vibrate for a little while.  It's also the same reason you get puffy eyes in the morning, until gravity can do its thing and help the fluids leave.
If you sleep with your mouth open,  your vocal chords can dry out too. That also changes the way you sound.


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

[User]
ELI5: why do snipers have to take the Coriolis effect into account even though the shooter and the target spin together with the ground?

What I mean is : if you shoot a projectile that travels 500 mp/h from a truck that goes 50 mp/h in the same direction, the bullet goes 550 mp/h relatively to the ground but 500 mp/h relatively to the truck because the truck's momentum transfers to the shooter and the rifle.
Same goes for jumping on a plane : it doesn't escape from under your feet.
So since both the shooter and the target spin, why do you have to take Coriolis effect into account?

[Assistant] If the bullet is traveling north (EDIT: in the northern hemisphere) then the target is moving east slightly slower than the shooter (in the extreme, a target at the North Pole has no eastward speed, it's just rotating in one place). The bullet maintains the eastward speed that it had when fired, so as it approaches the target it appears to curve to the east because the target is moving slower.


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

[User]
ELI5: PTSD, Post Traumatic Stress Disorder

I just need to know what this actually signifies. I see the wiki page for it and things and know what triggers it but I just need to know what it is I guess. My mind can't seem to process it for some reason lol. I know there's treatment but is there a permanent solution other than medication? And how exactly does sertraline (zoloft) work?

[Assistant]
When you were little you used to get Mrs Fields cookies whenever you visited your Grandpa. There wasn't a Mrs Fields in your neighborhood, so it was a feature of every trip you would take to visit them. After a while you move out on your own, you don't visit as much, and when you do, you don't go out for cookies. Except one day, you're out with your own kids and you pass a Mrs Fields cookie shop. For five or ten seconds, you're five, not thirty-five, and you're holding your Grandpa's hand while waiting for a delicious slab of gooey chocolaty cookie. The memory is almost completely overpowering and you have to sit down for a minute. Meanwhile, your kids are wondering why their Mom is zoning out in front of a little mall kiosk.

Now, replace getting a yummy cookie with the worst thing that ever happened to you in your life. Maybe when you went there something horrible happened. Instead of happiness and fuzzy fluffy memories with your Grandparents, you think of how scared and alone and in pain you felt. You think of people who can't think any more. You think of not being able to run away, and you think of how helpless you were. And you might even think about the horrible things you did to get out of that situation.

That's PTSD.