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

[User]
ELI5: why arent gas stations required to close during lightning/thunderstorms?

I would assume theres some protections in place?

[Assistant]
Because whilst a lightning strike might be a good ignition spark for explosive gases, every other smaller event even closer to the pump is a much bigger concern for the fire risk, such as:

- static discharge when touching your car after getting out

- switching on an uncapsuled light-source (door lights, headlights, etc.)

- starting of an engine (the relay that powers the starter)

The direct lightning strike is very unlikely to happen and the gaseous mixture at an outdoor gaspump rarely reaches combustable ratios of air/gas.


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

[User] ELI5: why are some people are more prone to insect bites?

[Assistant] I don't know about other bugs but mosquitoes have a preference for type O blood. CO2 also attracts them, and pregnant women exhale more CO2. Also alcohol (as little as 12 ounces of beer) seems to increase their attraction to you; possibly because it raises your body temperature.


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

[User]
(Gundam) How do pilots get such precise control over their mobile suits?

With the exception of I believe Mobile Fighter G Gundam, the cockpits of Mobile suits often seem quite plain and have basic controls. How do pilots control their suits with such precision?

[Assistant]
They aren't controlled like a car or a plane. In fact, their controls were originally inspired by early 21st century video game animation, where pre-set animations would be blended together to produce realistic-looking movement.

There's actually a lot of software in the suits that makes them move automatically. These presets were originally developed from videos of martial artists and soldiers practicing. A suit can actually drive itself if you queue a list of commands.

But there's a good reason you don't let them drive themselves. The suits are pretty bad at avoiding obstacles, and they're also really bad at deciding whether an obstacle is solid or going to give way easily. A suit's navigation computer simply doesn't have the processing power tell the difference between a boulder and a tent, and it just isn't fast enough to relay that the to movement controls quickly enough to prevent the suit from making a misstep and damaging itself. That's where the pilot comes in. (You also can't run them remotely them because the risk of jamming is too great.)

The pilot (after a lot of training on the presets) directs the suit to perform various preset motions. Forward movement, backward movement, turning, etc, are all very simple presets which, by default, are bound to a single joystick, and other movements are bound to various triggers, buttons, etc. The genius of the suit design is that the pilot can override ANY preset movement, or just parts of the movement, to move how he desires. This is facilitated by having the pilot queue the desired preset, then use his console to select a joint or set of joints to move as he desires with a thumbstick or several thumbsticks. Pilots can also blend two movements together, averaging the impulse on each joint or sets of joints (similar to how video games will blend upper body and lower body animations to make walking while shooting look nice).

With training a pilot can queue up a customized movement in a quarter of a second, fast enough to step over an obstacle, duck under an overhang, or reposition a melee attack to land on an exact target. Obviously this requires a bit of planning too, in combat most pilots will keep several modified commands ready in queue at any time so that they can react with whichever is needed. Experienced pilots will even record themselves to create their own custom sets of movements to get finer control over their suits.


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

[User]
Why does the body "need" 8 hours of sleep?

The reason I put "need" in quotes is because not everyone needs 8 hours, but that's the recommendation.

What I'm wondering is, why is it this long? Is there some process that our body is doing that takes hours to accomplish? Metabolizing something or storing memories perhaps?

EDIT: I should probably clarify, the main point of this question is not "why do we sleep?" It's actually a more specific version (that I now realize, nobody really knows for sure): "what requires X hours to do in our sleeping bodies?" This latter question, of course, would probably be helped by an answer to the former.

[Assistant]
Man, this topic has come up quite a lot these few days. Anyway, allow me to spill some information. Sleep is a mechanism triggered in the brain. It isn't something that we require for the full alotted time (I see someone mentioned Ubermanns already). As an adaptive mechanism, the brain can function quite well off of 4 or less hours of sleep at a time, but only if it's been shaped to do so. The typical "8 hours" is a standard norm generalized across all people. Just like those "2000 calorie diets" or shirt sizes.

As far as your 2nd question, Yes. This ties into the first question, the specific process in what we as humans 'need' (and i say this term VERY loosely) in sleep. A process within sleep that we, as humans, benefit from is R.E.M. You can 'sleep' for 12 hours, but be woken up before entering R.E.M. stage each time, you will feel drained and fatigued the next day. However, let it be known, Sleep is never DIRECTLY responsible for causing death or injury if you tend to deprive yourself from it. Other factors such as a weakened immune system or overbearing fatigue can cause it.


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

[User] ELI5: why do street poles, like traffic lights and lamp posts often have two bolts thread BENEATH it raising it from the ground, before then having bolts on top holding it down?

[Assistant]
Theyre called leveling nuts.

When they install light poles they first cast the foundation into the ground with the anchor bolts cast into the concrete. After the concrete is hard enough they come back with the light pole to bolt it on, but the top of the concrete isnt going to be sufficiently flat - the unevenness of the surface would have the pole at an angle.

So they cast the bolts to stick a good distance out of the concrete then install the ~~bolts~~ *nuts* below, and carefully adjust them to get a level surface. Then they screw a second ~~bold~~ *nut* down hard on the first to lock it in place. Then they bring in the light pole, set it down, confirm its plumb and then bolt it down from on top.


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

[User]
How does amputation affect the amount of blood contained within the body?

So for example, if somebody had both their legs amputated. Would the body very quickly adjust to this and ramp down production immediately? Or would it instead change the pressure of the blood within the system in the short term, then decrease the total amount over time?

I read a little about baroreceptors to try and find out, but I don't know.

[Assistant]
Blood pressure is mostly regulated by two processes: cardiac output (how much blood the heart is pumping per minute) and mean arterial pressure (basically the average tightness of the tubes). Both of these things are regulated by certain things as well. Cardiac output is related to how much blood the heart gets in and how hard and fast it pumps. Mean Arterial Pressure (MAP) is related to hormones such as adrenaline as well as chemicals like CO2 and lactic acid.

When a limb is amputated, there are two options to deal with the blood vessels. One is to seal them off (most common) and the other is to connect them to each other as a shunt. If you assume minimal blood loss from the surgery, then as you mentioned there is now more blood per unit are than there was before. The immediate reaction to this is for the pressure-sensitive baroreceptors to signal for the release of hormones which loosen the arterioles. At the microscopic level, the small vessels called capillaries are not strictly pipes and can leak fluid into the tissues which leads to swelling known as edema.

The heart will also be signalled by these chemicals and initially will pump less rapidly and effectively. Soon however, since the loosening of the arteries leads to more space for the blood to be in, the heart starts getting less blood coming in and it will soon resume its normal function. Regulation of blood pressure is actually quite a fascinating topic and the problems when that regulation fails lead to many different consequences that affect billions worldwide.


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

[User]
[DC] Superman Primes "recton" punch and some more

So, Prime was strong enough to break casuality apart. How did that work? Was he in a special place, a weak point in reality where it just become possible, so any other superman who happend to be there could do it? Did he have a special power? Was he born with this power (since different supermen have different power levels?) or did he somehow achive it? Does all his special powers (immue to reality warping, able to break out of the speed force, stand on the source wall etc) come from himself or did he collect them somehow?

[Assistant] The paradise realm that Superboy-Prime found refuge in was situated in between realities of DC Universes. Each punch caused a vibration that ultimately altered the histories of different realities. His powers are derived from the time spent in the nexus and the unravelling of his own mind as he becomes increasingly insane.


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

[User]
ELI5:How did Coca Cola become the world's most famous drink brand?

I remember asking this in high school in social studies, and the teacher just replied "Because it tastes good. Next question?"
But now I'm sure that there are other pivotal reasons, such as prohibition and marketing campaigns in a globalizing world.

[Assistant]
I believe it has something to do with World War 2. Coca Cola had a large contract with the government at the time and they were able to open a bunch of bottling plants with the Allied advance through Europe.  This allowed them to readily manufacture and sell their product to Europeans and GIs coming home had a taste for it. Coke pretty much took off from there.

Edit: Did some digging and found that in 1943 Eisenhower requested Coca Cola provide materials to open 10 bottling plants in Europe. This claim says it layer the foundation for it to reach the global market.


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

[User] Do black holes move in space like planets and stars do? and what would happen if a black hole ran into another black hole?

[Assistant]
>Do black holes move in space like planets and stars do?

Yes.

>and what would happen if a black hole ran into another black hole?

Not quite sure (beyond they would merge into one big one) and we've never seen it, but models suggest a lot of energy would be released.


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

[User]
Why is chlorophyll green? Isn't there a more energetically favorable color?

Chlorophyll being green mean is absorbs in the red area of the spectrum. Isn't this low energy light? Wouldn't plants get more energy if they absorbed light in the violet area of the spectrum?

[Assistant] Chlorophyll-a, the common green pigment you are referring to, isn't the only pigment in your average green leaf. There is also chlorophyll-b and the carotenoids, which broaden the light energies (colors) absorbed by the leaf. These are appparent during the fall as the leaves change color. Chlorophyll-a is important and most common because it doesn't only absorb energy, but it also facilitates the chemical reactions that allow the plant to use that energy.


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

[User]
ELI5 - What exactly makes the Playstation 3 so hard to program for compared to the Xbox 360?

I have heard from a lot of places that the PS3 is/was "a nightmare to program for," but no one can seem to explain exactly what it is that makes it that way. What about a game's code has to be changed to work with it and why is it so hard to do? It seems like developers who specialized in the PS3 could do some amazing things with it.

[Assistant]
Xbox 360: three horses.

PS3: one horse and TEN THOUSAND HAMSTERS.

Everyone knows how to build horse-drawn sleighs, but hamsters are new territory. If you add up how much power you can get out of the system, the PS3 wins hands down, but the hamsters are hard to get organised and if you just naively take the sleigh you built for 360 and plug the PS3's one horse into it, ignoring the hamsters, it's not gonna work very well.


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

[User] ELI5: Why does rolling up clothes (especially t shirts) seem to save so much more space than folding them normally?

[Assistant]
Every folded crease is like a spring because one side of the fold is compressed while the other side is stretched. For example, try folding a piece of cardboard so that both halves lie flat against each other. If you let go, it tends to spring back upwards.

Folded clothes have the same effect. Each fold acts like a spring that props up the item so that it takes up more space when it is sitting still.

When you roll clothes, you are not adding any sharp folds and the act of rolling compresses any of the existing folds. This is why it has less volume!


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

[User] Eli5 why aren't trains automated?

[Assistant]
In the event that something goes wrong, you want a human on board who knows how to operate the train. Since it's quite challenging to get someone onto a moving train after the problem has occurred, the company running the train needs someone onboard at all times. You want that person alert and not sleeping on the job, so you give that person something to do at all times that keeps the train running.

Since you already have someone onboard that needs something to do, you might as well have that person driving the train.


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

[User]
[Marvel] What is Captain America's Army Physical Fitness Test (APFT) score?

He's obviously on the extended APFT score chart, but I wonder how high it would be.

[Assistant] His 2 mile run is less than 5 min, and in the extended score, you gain a point for every 6 seconds under the 100 pt time, so he could get a passing score with just that one test. The ranger test (5 mile instead of 2 and some extra tests) would be more appropriate in theory, but as his body eliminates fatigue build up, the gap would only widen as regulars would grow more tired as the test went on and he stayed essentially the same.


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

[User]
ELI5 : In the age of HDTV and DSLR Cameras, Why are CCTV footages like 1980's TV resolution?

Even when storage is so cheap today!

[Assistant] A CCTV system can consist of hundreds of cameras and video could be retained for 30 days, in some cases even years. Hundreds of tb's of storage may be required, your cost to store can easily double or triple as you  jump from SD to HD and double from HD to 1080p. Frame rate and resolution is totally relevant to cost.


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

[User]
How do they polarize glass?

Evert time i google how polarized glass is made i get some non-technical stuff about how they are good for fishing, reduce glare, remove horizontal light waves. One article mentioned something about iodine crystals but didn't elaborate.

I just want to know how they treat the glass to get the polarization effect.

[Assistant] There are many different ways, one is simply placing a PVA (poly vinyl acetate) foil on the glass. This material approximately has the consistency and thickness of plastic wrap. The manufacturing process begins by heating and stretching PVA to five times its natural length, making it even thinner. This lengthens PVA's long chain molecules, causing them to align. The stretched PVA is then dipped in iodine solution. The iodine is absorbed into the molecular chains forming long grids of parallel, darkened lines that are not visible to the human eye. The film is then dyed to the color of the desired finished film. The darker the film, the more polarization it provides. In the last step, the film will be applied on the glass.


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

[User]
[Star Wars] How did Vader/Anakin become a force ghost?

My understanding is that you need to prepare yourself to turn into one before you die, and when you do your body disappears and you become a force ghost, as we saw when Ben died. However at the end of ROTJ Vader/Anakin dies and shows up as a force ghost at the celebration even though he didn't prepare and his body didn't disappear. In fact he was later cremated.

[Assistant]
We only see the armour burn, not Vaders body.  His organic body dissappeared when he died leaving his synthetic parts behind for Luke to burn.

Becoming a force ghost requires intense mental and emotional training to become one with the force. Vader had that in spades. But a key part of it is confronting your inner darkness and defeating it. We see Yoda do this in the Clone Wars.

Vader did this when he abandoned and killed his dark master to save his son.


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

[User]
[Lord of the Rings] Has the One Ring ever refused to corrupt someone?

I dont mean has it ever been *unable* to do so. I mean, has there ever been someone so stupid, lazy, annoying, or otherwise useless that the Ring simply saw no point in corrupting them?

[Assistant] The One Ring does make choices in who it corrupts it appears. Smeagol was with his friend Deagol when Deagol found the ring. But it was not Deagol that the ring focused it's corruption on, it was Smeagol, because Smeagol almost immediately killed his friend for the ring.


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

[User]
How reliable is Economists (and Econ research) from CATO Institute?

Just the title. I have heard about CATO institute when I was into 'climate skepticism' and all that conspiracy stuff, and CATO was a 'climate skeptic'. Today while listening to Economic Times podcast (Indian edition), the guest was an Economist called Swaminathan Aiyar, a guy from CATO institute but also associated with World Bank, and he was talking about India's new Budget where he was praising our governments' policies but called them a coward too because according to him, the government should be privatising more and more stuff.

How reliable are these guys?

[Assistant] They are an explicitly partisan (libertarian) think tank. So you can interpret any opinions from their staff through the lens of an active political agenda. They dont do scholarly research so Im not sure what else you need to know.


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

[User] Can there be a silent bomb?

[Assistant]
Bombs work by transmitting mechanical stress through solids or the atmosphere. Pressure waves in the air is how we sense sound, so any kind of detonation with the potential to cause destruction in this way will produce sound.

Edit: if you're talking about a broad definition of 'bomb', a device that releases radiation without an explosion will not necessarily have to produce sound.


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

[User]
[DC] How much time do you think Bruce Wayne takes to recover the money lost everytime he destroys a Batmobile/Batplane?

Fellow comic book nerds. It's your cue. Has it been mentioned in the comics how exactly rich Batman/Bruce Wayne is and his income is?

Question is kind of difficult so here's a comparison.  I once read that if Bill Gates dripped a 100 dollars he wouldn't bother to pick it up because by the time he would pick it up he would already have earned doubled the money.

So by that logic, if everytime Batman crashes a Batmobile or destroys a Batplane, how much worth of money do you think he loses and in what time does he recover the money (through his company ofcourse not insurance because Batman doesn't have insurance ofc)

[Assistant]
Lets say he has 5 billion dollars, lets say he can always make 3% on his money.  That's a 150 million a year in income. As a very safe estimate.

I think he can afford to lose a batmobile a month.

Or a batplane once a year.

Conservatively.

Imagine Bruce Wayne is that smart and can detect investments like Netflix, Google, Facebook, Amazon, very early in their development.

His income could be even higher.

That's not even including any new inventions he has patented in the last 20 years.


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

[User]
[Avengers: Endgame] So everyone that was snapped away has just been brought back, is there enough food?

It's been 5 years since they were snapped away and food production has adjusted to the new population size. How on earth are we going to manage to feed double the population overnight?

[Assistant]
Double isn't that bad for the west.
The average western nation wastes HUGE amounts of food. And people can spin up a bunch of production fairly fast.

Power usage is far more concerning. And hundreds of support industries.

Sure you've got the people with skills like you always had, but there's new people in those roles now. Production lines and transport has changed. The entire world is thrown into chaos. millions of people in someone else's home. People have moved onto new relationships.

Food is probably the least disastrous of the horror it caused.
And Far From Home significantly glossed over it all.


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

[User] Does the expansion of the universe increase the travel time between the earth and another point of the universe ?

[Assistant]
Within our local "gravitationally bound system" that is not expanding along with the rest of the universe, no.  To get from Earth to Jupiter, or another star in our galaxy, or a member of the "Local Group" like Andromeda... no.

But, to get to a galaxy far far away... yes.   The expansion creates more space out there, so it takes longer to traverse it.


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

[User]
ELI5: Why do some people have such a difficulty remembering names?

I have real difficulty remembering names of people. It is really frustrating sometimes. Someone could introduce themselves, and halfway into the conversation, I would forget their name. I have friends who are able to instantly remember name that was mentioned once in a conversation and recall it years after.

Why? and is there a way to improve this?

[Assistant] Its probably the fact that a name is introduced first and then comes the information with which people recognize a person. Physical characteristics, voice, behavior and whatnot will leave a bigger impression than just a name.


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

[User] [Wacky Races] Age-old question: Why does Dick Dastardly always stop to cheat?

[Assistant]
Oddly enough, principle. In one episode, he does almost legitimately win, and goes back to cheat anyway. He doesn't want to win, he wants to win *unfairly*.

It's unclear why, but leading theories hinge on the fact his name is fucking *Dick Dastardly*


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

[User]
[Street Fighter] Based on established guidelines and examples for power, Isn't Dee Jay incredibly strong?

Okay, a little background in regards to Ki and energy projection in the street fighter universe first. Basically, any of the martial arts fighters such as Sagat and Ryu take their willpower and Ki and transfer it, with the proper technique,  to extend it in the form of a Hadouken, Tiger shot etc. Contrary to popular belief, these don't actually "Set" you on fire, and being hit by one is akin to getting punched, obviously depending on the strength of the fighter.

Now, even being able to throw a fireball in the SF universe is a BIG deal. Average Joes have to idea how to use Ki, and even those who have devoted a long period of time studying martial arts usually can very rarely produce physical manifestations of Ki (For Example, Rufus from SF4). Obviously you don't have to use ki in that way to be an extremely powerful fighter, but both training and inner strength are required to produce balls of Ki from your hands.

Now, canonically, Ryu and Ken both need to focus and use 2 hands to do Hadoukens, and even then, It's not easy, and requires intense focus and energy. Throwing a hadouken with ONE hand is saved for only the baddest of the bad.

In all of the canonical SF universe, only a powerful few are able to throw a fireball with one hand. Gouken can, but he's the master of Ansatsuken, granted his own version of it, and he has incredible strength. Akuma, the only other person capable of really standing and fighting with Gouken, can throw a weaker version with one hand, but not to the ability of Gouken. Only his demon form, Oni, can throw one with one hand, and even then, while large, it travels a short distance, showing even for somebody who has transcended humanity, fireballs are extremely difficult to do.

But when we reach the seemingly inconsequential character Dee Jay, he seems to show a mastery of his own Ki. Not only can he seemingly throw fireballs with one hand with ease, but he can even throw two at once in rapid succession. Based on previous examples, wouldn't this mean he's EXTREMELY powerful, even moreso than Ryu or Ken?

[Assistant]
Dan can throw a fireball with one hand so....probably not the best example. Dee Jay is a good, unorthodox fighter but he's not Ryu-tier.

Other one-hand fireball throwers: Remy, Charlie, Chun-Li (Third Strike Kikoken), Oro, Poison (uses a whip, technically), Ibuki (if you want to consider Yoroitoshi a "fireball"), M. Bison (Psycho Cannon), Juri (Fuja-hin done with one leg), Decapre (Psycho Stream Ultra), Rose (Soul Spark).

In retrospect its a pretty common ability.


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

[User]
ELI5: Why do our bodies store excess fat, sugar, cholesterol etc but not water or vitamins?

It's pretty annoying to have to drink water all day, throughout the day in proper amounts. Not enough? Headaches, dry mouth, etc. Too much? "Oh we don't need this right now. Pee it out!!!" Same with vitamins. Extras just get excreted out so you have to gradually consume them to stay healthy.

But yet you eat too much fat, sugar, or cholesterol and your body is like "hey let's hang onto this, we might need it in 27 YEARS!!!"

Why is it so inefficient about what it does/doesnt store?

Edit: Wow thanks to everybody who answered! Apparently we do store vitamins and minerals. I thought we didn't because i heard taking supplemental vitamins was a waste because our bodies just pissed out the extras.

I'm still salty about needing to drink water constantly though. I work in a microbiology lab and have a lot of PPE to deal with every time i leave and reenter the lab to drink. I can't even chug a gallon of water and be good for the day; it has to be gradual.

Edit 2: Oh goodness too many replies to keep track of but you guys rock

Edit 3: Gold! Thanks strangers! And it turns out our bodies store water as well. Just not how i thought. But my eye does twitch when i drink a boatload of water one day, pee most of it out, then next day my body is like "heyo i want more water even though I got rid of most of it yesterday".

[Assistant]
Because water is actually pretty hard to store. We need a *lot* of it, far more than we need fat or sugar. Water is also pretty easy to obtain, so we don't *need* to store it. Things that do only do so because they can't get it regularly: cacti, camels...

Water is also not only something we discard, it's how we discard *other* things, things that we have to discard due to their toxicity like urea. A high water intake and output is important for our overall health because it keeps us efficiently removing toxic waste products from our systems.

We actually do store certain vitamins - fat soluble vitamins. Some vitamins are water soluble though, so we have no way of storing them. To store any chemical our body has to sequester it from the water inside our cells. Fat-soluble molecules naturally remove themselves from water anyway, but water soluble ones have to be made water *insoluble* in order to store them, which means modifying them so that they're not vitamins anymore.

The problem with storage of fats and sugars is that we evolved to be able to survive droughts and other unpredictable conditions. We store excess energy (in the form of fats and sugars) so that we can't be caught off-guard if we ever enter a period of starvation. Fat storage is also a useful insulating tool remaining from when we hadn't invented central heating. So, we have all these mechanisms for storing fats and sugars, but we now live in an environment where starvation pretty much never happens unpredictably and we don't need to build large energy stores. The body always assumes the worst because it's evolved to do so, and if you're over-eating regularly its assuming that a starvation period is coming. So if you're constantly over-eating your body is constantly trying to stockpile energy in fear of an oncoming winter or something, but that never comes and you just keep on eating.

The body is actually *incredibly* efficient about what it does and doesn't store. It stores everything it needs to be able to store (and can store at all). That's how evolution works after all - it tends towards making the most efficient versions of things possible, as long as more efficiency means a higher survival rate. If it doesn't need to store more energy, then it sends us messages telling us we don't need to eat. If you're storing more fat and sugar than you need, it's because you're *eating* too much fat and sugar, ignoring those messages, or because of some genetic defect that is meaning that messaging system isn't working properly. Or because of gut bacteria. That's the new focus of dietary science.

Also, the reason we can't store water soluble things is because it's actually toxic to do so. A lot of our body works on the relative concentration of water soluble molecules, and if we have too much of a water soluble molecule, we actually can't absorb any more of it without converting the water soluble molecule to an insoluble form. We actually have to use a very advanced mechanism to absorb glucose at all, that relies on the fact there's more sodium in our intestine than inside our cells.


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

[User] ELI5: Why have we not paved the deserts with solar panels yet?

[Assistant]
People generally don't live in deserts; this means the solar power plants would be pretty remote. This causes a few problems:

* A great deal of energy is lost in transmission i.e, while travelling through the power lines. That loud hum you hear when standing under power lines? That is waste energy. More is lost as heat. The further the energy has to travel, the more is wasted. There is also the expense of building and maintaining these power lines.
* Power plants need people to maintain and operate them. With a solar farm, the main issue would probably be servicing. You'd probably also need to employ security, since all that copper wiring alone would be worth stealing. These people would either need to be brought in every day from somewhere they can live, or they'd need to be housed at the plant and have food, water, etc brought in.

Improvements are being made in the efficiency of photovoltaic cells (solar panels), and it may soon get to the point where it becomes cost-effective to put a shitload of them in the deserts of the world. As fossil fuels (coal, gas, oil) become more scarce, solar power may become cheaper by comparison.


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

[User]
ELI5: Why do most MMO's have reset on a Tuesday?

I can vouch for FFXIV and WoW. I think Overwatch is also Tuesdays.

What is it about a Tuesday?

[Assistant]
Balance of staff availability and user traffic.   Regular tech staff only work Mon-Fri.   With network support center running nights and weekends.

You never change anything on Friday, thats just rule #1.

You need Monday to catch up on everything from the weekend.

So that just leaves Tuesday Wednesday and Thursday.   Tuesday is earlier in the week so you can see what flak appeared and have option to do hotfixes.    You have less opporrtunity window  if you do Wednesday and no window if you do Thursday.


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

[User]
Why are we immune to some diseases like chickenpox after having it, but not others like strep throat?

Chickenpox is caused by the varicella-zoster virus and once you get it, you can't get it again because your body has produced the antibodies to fight it. Why is this not the case with strep throat which is caused by either a bacteria or a virus? Can you get sick from the same virus more than once?

[Assistant] Because strep throat and flu like viruses mutate much more often that many other viruses. Once you get the flu you're immune to that certain flu virus but by next year it will have mutated and a new flu virus will come around that you're not immune to yet.


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

[User]
[Angel/Supernatural] How do Sam and Dean handle Angelus?

So Sam and Dean get transported to the Buffyverse. Angel has lost his soul and Angelus knows enough about Sam and Dean to play his typical mind games with them. Would they be able to stop him?

[Assistant]
In short: probably not.

Sam and Dean Winchester are used to dealing with vampires only slightly stronger than normal humans and, well, Moose is stronger than most normal humans.

But in the Buffyverse, vampires are superbeings in comparison to humans. The only humans who fights vampires without the help of paramilitary assistance are The Slayers, who are physically a match for vampires and other forms of demons.

Angelus could physically fight and kill both Sam and Dean without much difficulty. Add to that the mental torment he loves to unleash as he toys with his prey, and the outcome is all but certain.

That said, Sam and Dean are resourceful and have been underestimated before, so there's always a chance...


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

[User]
ELI5: When a person gets one of their appendages amputated, how does the blood get back to the heart?

Do they have to attached the blood vessels together? How did they do this in like the wild west or back in the late 1700's?

[Assistant]
Blood doesn't rush around your body in one big tube.  What happens is the blood vessels split and become thinner and thinner.  Think of a fan where the bottom is the main artery which splits into finer tubes called capillaries.

This splitting happens all through your skin, so there are millions of very fine capillaries covering your body.  Once the cells have taken the oxygen from the blood through the walls of the capillaries and given up the waste products back into the blood,  then the capillaries then all join back up again into veins and travels back to the heart.

So,  when you chop off an arm some of the fine capillaries are lost but the vast majority are still there. The amount of blood and the pressure of the blood get messed up for a while,  but the circuit still exists.


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

[User] eli5: How does the air pressure in a airplane change depending on altitude if the plane is sealed shut?

[Assistant]
The plane is not sealed completely shut.

Compressed air is tapped off of the the engines (bleed air), and this then goes through the air-conditioning packs and into the cabin. There are then outflow valves in the fuselage where the air exits, so there is a continuous circulation of air. The outflow valves are controllable to set the cabin pressure.

The reason that the plane isn't pressurised up to ground level pressure is to reduce stress on the airframe through the repeated pressurisation/depressurisation cycles.


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

[User] ELI5 What is the purpose of the little individual hairs on tires?

[Assistant]
Absolutely nothing. They are just manafacturing artefacts, either injection ports, or air escape ports, rubber stays behind when the tire is removed from the mold.

They do no harm, they usually wear out after a few miles, and everyone's happy. Manafacturer didn't waste time/manpower to remove something that's completely irrelevant, and the customer gets an indicator that the tire is brand new.

EDIT: Thanks for the rewards and the upvotes. To add some more info from people who actually work in tire industry down below: these are air vents, so that when the tire is shaped against the mould, air can escape, and due to pressure some rubber starts pushing out also. This is not universal to all tires, some use a different mould that does not leave these artefacts.


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

[User]
[Star Wars] Why did the Death Star trench have turbolasers?

In their location, their field of fire is severely limited by the trench walls to the trench itself and directly above it. If the Imperials don't view starfighters as a valid threat, why have dedicated turbolasers to protect a location that would never be occupied by enemy starfighters? The same turbolasers if mounted on the surface could contribute to defense against large fleets of capital ships and starfighters that are above the surface without any increased financial cost. If the Imperials did not know about the thermal exhaust port vulnerability, why would they need dedicated defense in the trench?

[Assistant]
The Death Star's main gun has an incredibly narrow field of fire. Some genius might get the brilliant idea to just drop out of hyperspace "behind" the Death Star, well out of reach of the main gun. So you put turbolaser batteries to send whoever does try that to hell in a handbasket, as you've noted.

So if no capital ships can get close, why bother lining the trenches with additional batteries?

While starfighters may be a threat, the Death Star does have its own wing of superiority fighters which can be scrambled to engage them. Imperial pilots are, after all, well-trained enough to put down such rabble, and indeed, we see them used as a primary measure against the rebel assault in A New Hope. The batteries in the trenches could be a defense-in-depth measure to catch any pilots bold or stupid enough to fly low to the surface of the station to evade the starfighter screen. I'd wager this is a probable purpose.

But let me present to you an even more unlikely situation: boarding parties.

The Death Star is massive. There's no feasible way fighter patrols can keep an eye on the entire station's surface area all the time. So sneak a transport into a blind spot, like a trench, and pray you get enough time to infiltrate the station. If the infiltration goes off without a hitch, you'll have insiders ready to act and make the station vulnerable from within.

What's the counter to this feat of absolute stupidity? Turbolaser batteries in the trenches. The gunners on the batteries will keep an eye open and effectively act as a stationary patrol, allowing the starfighter complement to not need to fly over the entire station all the time. An effective solution to a very unlikely (but high consequence) issue.


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

[User]
[Marvel/DC] Whats the weirdest alternate universe version of a character.

My moneys on the 4 armed version of spider-man.

[Assistant]
Marvel? The alternate universe where Spider-Man is a Japanese man who got his powers from aliens and summons a giant robot he uses to fight monsters.

DC? The alternate future where old man Superman uses giant guns to fight cloned twins of Hitler.


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

[User] Why does meat from different animals taste different?

[Assistant] Short answer: there are different proteins in different types of meat. What makes up the diet of the animal can change the fats and chemical composition of the animal too, so even within species you can have different flavors.


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

[User]
[Men In Black] How come access to the file relating to Kay's encounter with Boris in 1969 was restricted?

Spoilering this just in case.

So Men in Black 3 has 3 timelines.  Original, where Kay arrests Boris and gets the Arcnet up into space in 1969 and arrests Boris.  Then there's the altered timeline where present-Boris goes back in time and helps his past-self kill Kay in 1969 and prevents the arcnet from being used, which leads to a present-day invasion.  Then there's the mostly-fixed timeline that happens because Jay goes back in time and prevents Boris from killing Kay, and the arcnet goes up into space.  The major differences between the original and mostly-fixed timelines are that Jay and an extra Boris were present, and Boris is dead rather than arrested; likewise, there's now the possibility of Kay eventually recognizing young James as being the agent from the future as he grows up, since in both "Kay survives" timelines, he keeps an eye on the kid because his father died saving his life.

Now, in the original timeline (the one that exists without any influence from time travel), everyone is very sensitive about what happened in 1969.  Kay suspends Jay for an entire month for asking about it twice, and O restricts Jay's security privileges so that he can't access the files.  I understand that nobody wants to be the one to tell Jay *"oh by the way your dad died protecting your partner and you super got flashy-thing'd in the process, sorry I guess"*, but the lengths they go to to keep it from him, and just how upset they seem about that day in 1969 feels more like there's a secret they're trying to keep from everyone, not just him.  It confused me; it felt very *"this is a state secret, you CAN NOT find out"* and less *"we feel awkward for keeping it from you after all this time and don't want to tell you your dad died protecting a MIB agent"*.  It feels very hyped up, and made for good trailer material.

It was secretive enough that at first I thought that the people in the original non-time-travel timeline somehow knew that time travel was about to occur, and they REALLY didn't want him to find out details about what he would do in the past because paradoxes.  But that doesn't make sense because no time travel happened in that timeline.

Am I overthinking this?  Is it really as simple as *"nobody wants to tell Jay that oopsie-poopsie, your trusted partner is sorta kinda responsible for your dad dying and he never ever told you, so we're just going to suspend him when he asks and restrict his security access so that he doesn't find out and make us all feel awkward"*?

[Assistant] Time travel is apparently illegal in the MIB universe plus it's about the planetary defense systems. Both of those are *super* important to keep secret, so keeping those files as restricted as possible is good security. You wouldn't want an alien to pose as an MIB agent and know where they keep the time machines/time machine inventors *and* know where the arcnet comes from (or at least what species so you could devise weaknesses) as a nice bonus.


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

[User]
Other than the Inuit sled dogs and Carolina dogs, are there any pre-Columbian domestic dog lineages left in the Americas? Additionally, is there much in a way of dog landrace formation in current Native American reservations?

Looking at wikipedia, there's been a number of extint breeds due to European contact, in North American neck of the woods...kind of curious as to whether there's much information available on existing dog populations.

[Assistant]
The most common dog that was precolumbian is the chihuahua, but here is the list according to Wikipedia.

Xoloitzcuintle
Carolina Dog
Canadian Eskimo Dog
Top to bottom: Xoloitzcuintle, Carolina, and Canadian Eskimo dogs.
North America:

Hare Indian dog
Salish Wool Dog [16]
Tahltan Bear Dog[17]
Tlalchichi
Xoloitzcuintli
Chihuahua
Calupoh [18]
Greenland Dog
Canadian Eskimo Dog[19]
Carolina Dog
South America:

Chiribaya Dog
Peruvian Hairless Dog
Fuegian dog
Breeds falsely advertised as Native American-originated:

American Eskimo Dog[20]
Chinook[21]
Northern Inuit Dog[22]


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

[User]
[Harry Potter] with the British voted to leave the EU, will this have any impact on England's magical society?

does this damage any relations the Ministry of Magic has with other government bodies from the EU?

[Assistant] Unlikely. The European Union is a muggle government thing. Whether the UK is in or out, wizarding England goes on as before with its own set of governing systems. Why should the business of muggles concern wizards?


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

[User] ELI5:Why do speakers make a buzzing noise when the volume is turned up?

[Assistant]
Speakers are powered by an amplifier.

An amplifier takes a low-level signal as an input, amplifies it, and pushes it through the speakers to make sound.

When no input is present, the amplifier basically amplifies the background noise. When you turn it up, as you might expect, it gets louder, and becomes more noticeable (but it's *always* there, in *every* amplifier, you just can't always hear it.) There is some amount of electronic interference from everything with electricity, including within the amplifier itself. This is where that buzz/hiss/white noise/static (whatever you want to call it) comes from. It's the sound of the amplifier being on, essentially.

Audiophiles refer to this as a "noise floor". When you start looking at higher end amplifiers, better parts and designs are used, resulting in less interference, and therefore, a lower noise floor.


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

[User]
Would planting corn in arid regions increase the likelihood of rain/precipitation?

I just read about 'corn sweat' for the first time and, y'all, my mind was blown and replaced with sooo many questions. The articles and links that pop up when googled all state sweat from corn, and like plants, can increase humidity in an area making humid areas more so (as in the American Midwest). If this is true, then can we assume it also applies to non humid areas? If it does, then, basically, my main question is the one from the title- Would planting corn in arid regions increase the likelihood of rain/precipitation?

Thank you!

[Assistant]
The answer is technically yes, but not realistically.

Corn can only give off water that it has absorbed, so you'd need to be providing it with a ton of extra water anyway.

So sure, if you plant a few million acres of corn in some dry area and provide it with the billions of gallons of water it requires, you might slightly increase the chance of the atmosphere reaching saturation and causing rain.

But you're probably just better off using that water for whatever you needed directly, at far less of a loss.


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

[User] ELI5: Why when I'm hungover do I not seem to want water/food even though I need it and will make me feel better?

[Assistant]
To specifically address the lack of appetite, it's usually inflammation-related.  Alcohol irritates the lining of the stomach and intestine.  The brain takes those sensory signals and says "something's not right in the GI tract, let's not put anything else in there until we're sure everything is ok".

Alcohol also affects the balance system in your inner ear as well, which can contribute to nausea depending on your tolerance for a lack of equilibrium.

In the end, there are lots of factors that contribute; alcohol is a very small molecule and can go pretty much anywhere in the body, causing different effects in different places.  Very ELI5 but hopefully that answers your question!


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

[User] ELI5: What's the deal with goofy-looking bowling shoes? Why can't they just look like regular shoes?

[Assistant]
IIRC, it's to prevent theft. They are ugly so no one will want to steal them, and readily identifiable so if someone does steal them, everyone will know they are a thief.

And at one point many small towns only had one bowling alley, so if anyone wore those shoes, it was apparent where they had been stolen.


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

[User]
Do different kinds of languages have different sounding gibberish's?

Gibberish can sound like a lot of things, but to keep this question relavent, I'd define gibberish as nonsensical talk that sounds like it could be a language, or using a consistent phonology perhaps?

Does the language you speak influence the gibberish you make up? Could the kind of gibberish you make up clue what language you natively speak? I am a native english speaker and I can't roll my r's so even when I speak gibberish there are sounds I can't make and that can clue my non spanishness. Do different languages have different general sounding gibberish's?

[Assistant]
Yes. People dont really articulate sounds they dont know how to produce accidentally.

Filler words like blahblahblahblah are also different. In Japamese we might say naninaninani (literallt what what what) or daradaradara (meaningless)


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

[User] ELI5: The relationship between Iran's Ayatollah Ali Khameni and their president and who actually governs what?

[Assistant]
The Iranian political structure is amazingly redundant, with checks and re-checks all over the place. No one person has the final say in anything with one exception...the Ayatollah. There also exists a dual military structure wherein there is a normal, regular military, paralleled by the IRGC, Islamic Revolutionary Guard Corps. The IRGC receives much more funding, are hand picked for their support of the Ayatollah, far better equipped, and loyal as fuck. The president is responsible for most day to day activities, but is more intended to be the public face of the Ayatollah's direction. Ahmedinijad has, at times, broken from that direction, and seemed to invite a sort of power struggle. The IRGC arrested him and reportedly brought him before the ayatollah last month, and about the events of that time speculation abounds, but it seems clear that he was basically told fall in line or fall off the face of the Earth.

Additionally, the president is "elected," but must as a candidate be approved to run by the Ayatollah. The elections are therefore subject to the Ayatollah's whims, and they have been swung in various directions by such whims. The Ayatollah is, conversely, appointed through the words of the previous Ayatollah, essentially a named successor.


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

[User]
Eli5: How do wind instruments amplify the sound that their instrumentalist creates without breaking the laws of physics?

The sound a tuba player makes with their mouth without the instrument sounds much lower than the sound that comes out of the tuba.

How can the sound feel so much louder without any energy being added?

[Assistant] The other people aren't really answering where the energy comes from. Basically, the instrument turns moving air that the musician is blowing out of their mouth, into vibrating air that we perceive as sound. And really, sound doesn't involve much energy. Like, an instrument might put out just 0.001 W of power in the form of sound. That's tiny, much less energy than the kinetic energy of the moving air you blow out of your mouth. So, by converting just some of the energy of the moving air into sound energy, you can make a loud sound.


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

[User] ELI5: Why does licking your lips when they are chapped give temporary relief but then they become more chapped than when you started?

[Assistant] Because you are removing the protective oils and physically irritation your lips each time. The result is that it gets your lips wet again (the instant relief) but then because that barrier is gone that water quickly vanished, and now youre worse off than when you started (because youve sandpapered away that protective layer).


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

[User] If you were to continuously brush your teeth would there eventually be a point where it would no longer be beneficial?

[Assistant] Yes! Not only will further brushing not help anything it will actually hurt your teeth! Brushing your teeth for long periods of time will actually damage them and make them yellow! Your tooth enamel is what is nice and white and shiny. It is a layer that protects your teeth. The layer under the enamel is called dentine and is actually yellow. So while surface stains can yellow your teeth the biggest cause of yellow teeth is loss of enamel. Excessive brushing will actually wear away your enamel and make your teeth yellow and more susceptible to damage. Also there is no way to restore enamel currently, once it is gone it is gone forever.


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

[User]
How does a charged particle not lose all of its energy even though it constantly generates an electromagnetic field?

If a charged particle creates an electromagnetic field, doesn't the information in that field have to be carried by photons to "sense" whether or not there exists another charged particle in the field? As far as I know, information can't be shared or transferred without using energy, and charged particles share information using photons.

However if all charged particles are constantly giving off photons to generate this field, how is it that they don't lose all their energy?

I'm sure there's something I'm missing, and I would really appreciate some clarity.

[Assistant]
The electrostatic field of a charge *has* or *carries* a certain amount of energy and information. It does not need a *constant input* of energy or information from the charge. It does not "emanate" or "flow" outwards from the charge.

It's like a dress, not a waterfall. You don't need to constantly produce fabric to have a dress on.


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

[User]
CMV: The term "Karen" has devolved into "Woman who says/does thing I don't like/disagree with" and has become completely worthless

So this has been on my mind for a while, but the recent twitter exchange in which Elon Musk called Elizabeth Warren a Karen for wanting to alter the tax code to make him pay more (not saying I agree or disagree with the idea that he should, I do have opinions on the matter but that's not what this post is about) cemented it for me. It seems to me people kinda just jump to calling women Karen's at this point for very personal reasons. Another thing that really got me thinking about this was how it seemed like both women who yell at others to wear masks and women who refuse to wear them can be called Karen depending on the beliefs of the commenter, and they never really get criticized for using the term incorrectly from what I've seen. I don't have any issue with calling out people for being unkind to those working in retail or food service or anything like that, I've been bagging grocery's for around six months now myself and my best friend works at McDonalds. I just think that it's become a very arbitrary and useless insult. I don't know if I'm describing my position on this super well, feel free to ask more about what I'm saying in the comments.

[Assistant] I was always under the impression a Karen was someone who was outrageously entitled and believed the world should stop for them and their problems, especially when they scream and demand to speak to a manager because their Iced caramel macchiato was too macchiato.


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

[User]
ELI5: Eventually, where does all the dust in the world go?

Does it just get re-circulated? You clean your place and make your neighbour's place dirty, and vice versa?

[Assistant]
It gets absorbed into the environment one way or another.

Dust lands in sea; either gets eaten or turns to sediment.

Dust on land: hits the ground and stays dust, until it accumulates and becomes dirt (or dirt almost immediately on damp soil, or mud/sediment on wet soil, which would then just be dirt upon drying)

Dust in the air does a bit of everything. Gets breathed in where it gets added to regular waste processing, or eaten in the case of very small creatures depending on what the dust is made up of. Lands on things and see above.

Its all a big circle.

.....of dust.


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

[User]
ELI5: If the Human Voice resonates at multiple frequencies, how are we able to perceive singing as a single pitch?

In my Phonetics class, weve talked multiple times about how the voice resonates with multiple frequencies, since theres multiple chambers for it to resonate in. That leaves me confused then, with the titular questionhow are we able to perceive singing as marching up with notes that are a single frequency?

[Assistant] The voice is a harmonic sound, meaning it produces frequencies in a harmonic series.  Lots of sounds are harmonic, so we've learned to hear the entire harmonic series as "one sound", since it all probably comes from a single sound source, and the pitch is the frequency the series starts on (also called the fundamental frequency.)


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

[User]
How do drugs get into the brain?

I have read that LSD binds a specific Serotonin receptor which then fires with Serotonin causing the effects. But aren't receptors things in synapses? How does LSD get there?

[Assistant] Most drugs have structures that are incredibly similar to natural neurotransmitters! Not to get too into the organic chemistry but serotonin and LSD share the same indole rings. In essence, because of their similar structure, LSD can pretend to be serotonin and affect the same pathways and receptors. To get into the brain, the drugs have to pass the blood brain barrier (BBB). Since the structure is so similar to the natural neurotransmitters that are allowed through that barrier, LSD sort of tricks the membrane into letting it pass.


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

[User] How does France get rid of nuclear waste from more than 60 nuclear power plants?

[Assistant] France is among the nuclear powers who, unlike the US, has a closed fuel cycle where they reprocess spent fuel to separate still usable fissile material from the reaction byproducts.  Consequently, their quantity of high level nuclear waste that require long term disposal/storage are considerably less than you'd assume.  Their disposal facility is more than capable of handling their waste stream.  Also, their general population is not as nuclear-phobic as many other parts of the world.  Those who live near such facilities are willing partners to the endeavor who don't espouse the NIMBY attitude you find elsewhere.


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

[User] ELI5: How does my body know when I've had enough sleep and it's time to wake up?

[Assistant] It's hard to answer that because with today's knowledge we can't really explain why we need sleep, aside from the fact that we feel tired.  Not knowing why we get to sleep in the first place, it's hard to say why we stop sleeping.  To our knowledge the best answer would be: because we stop feeling tired.


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

[User]
How exactly is unused breast milk absorbed back into the bloodstream?

I read somewhere that whatever milk is left in the breast after weaning gets absorbed back into the body. But what exactly is happening there? How is the body able to absorb nutrients without involving the digestive tract?

I hope these are not extraordinarily dumb questions. I only have middle school level background in biology (and most other things).

[Assistant]
The cells in the breast that produce milk are going to either commit suicide (this is called apoptosis and is completely normal) or the connections between those cells and neighboring cells are removed and the cells die of starvation. Other cells come in and destroy the junk thats left behind and will get rid of most of the harmful stuff left behind. The clean up cells and the remaining cells will most likely take up and use the nutrients left behind. The destroyed cells are replaced with fat cells.

Breast milk contains protein, fat, and carbs. ~~All of these things can be pushed into the blood stream and easily degraded by the liver or just released in the urine.~~

Edit: a lot of the time, any milk left over after weaning will leak out of the breast. unless the ducts in the breast that carry milk to the nipple are blocked, there will be discharge. release of milk is caused by a few mechanisms and it takes a while (up to months) to destroy the majority of milk producing cells.

Edit 2: those clean up cells will do all the work (macrophages), VERY little of those proteins, fats, or carbs will enter the blood.


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

[User] [General Fantasy] What does the daily life of a Lich look like?

[Assistant] There's no such thing as "daily" for a lich. You no longer need to eat, sleep or breathe. You can see in the dark. Cold doesn't bother you anyway. In essence this is a perfect state for a wizard to be in. You can just sit and read eldritch tomes *ad infinitum*. Research new spells. Plan unholy rituals. Send your minions to procure rare components. Kill adventurers who tried to plunder your riches. Devour their souls. Rinse, repeat.


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

[User]
ELI5: Body Parts falling asleep; lack of oxygen or blood pressure too high?

When your leg/arm/ass/hand falls asleep and then becomes impossible to move, is that due to blood flow being cut off and so there is not oxygen, or is blood being stopped from returning to the heart so pressure builds up and nothing can move (like a garden hose with really high pressure, hard to bend)?
Follow up question: when blood flow is returned and we get that "staticy" feeling, is that oxygen returning to nervous system cells so feeling is regained?

[Assistant]
>lack of oxygen or blood pressure too high?

Neither.

It's caused by compression of nerves to/from the affected limb, effectively cutting off communication between the limb and the brain.  The "pins and needles" feeling is caused by the sensory neurons restoring their electrochemical gradients once the pressure is removed.


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

[User]
Why do astrobiologists set requirements for life on exoplanets when we've never discovered life outside of Earth?

Might be a confusing title but I've always wondered why astrobiologists say that planets *need* to have "liquid water," a temperature between -15C-122C and to have "pressure greater than 0.01 atmospheres"

Maybe it's just me but I always thought that life could survive in the harshest of circumstances living off materials that we haven't yet discovered.

[Assistant]
Well the short answer is that we can't look for anything else if we don't know what else we're looking for. We've seen one set of circumstances that apparently allow life to develop, so it makes the most sense to look for those circumstances elsewhere.

You can also make a number of arguments why, if we find life anywhere else, it will probably be carbon/water based, exist in a similar temperature regime, etc. For example, if you get much colder than here on Earth, things move around a lot less. You need motion to have life. If you get much hotter, then things move around too much and nothing sticks together long enough to come alive.


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

[User]
CMV: Autumn (Fall) is the best season and summer is the worst.

Why Autumn (I'm gonna say autumn but it is the same as fall if you didn't know) is great:

Not too hot not too cold, beautiful leaves and scenery, on the colder side and heat is terrible, delicious pumpkin and apple flavours, Halloween, Thanksgiving, more comfortable clothes (sweaters, scarfs etc...), All the bugs are beginning to die, no hay fever/allergies, and it is very cozy.

Now why Summer sucks:

Hot and sweaty weather, hard to cool down, bugs and mosquitos, always have to wear suncream, longer days and days are bad, everywhere is busier, the sun is way too bright, the beach is too sandy, hot and busy, barbeques are horrible, I hate eating outside with bugs and bees while I sweat all over the place, can easily get sunburnt, and Hayfever.

So CMV that Fall is the best and summer is the worst.

Btw I am in the UK for reference.

[Assistant] I like them all when theyre coming around. Looking forward to Autumn now - leaves changing colour, nice walks. Ill enjoy winter, short days and all cosy at home and Christmas and stuff. Then, Spring with new buds and wildlife waking up. And long summer days and evenings. Theyre all great when its their turn.


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

[User] ELI5 Why cant you eat as much food when youre starving hungry compared to when youre moderate hungry?

[Assistant] When you havent eaten in a while, your stomach contracts, making it feel full more quickly. When you havent gone as long without eating, your stomach is already stretched out a bit, and can take more before it feels as full.


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

[User] Why is the ocean so salty?

[Assistant]
You are ~~completely~~ mostly right. Salt exists in large deposits all across the globe. As water travels across the land, it picks up salt and other minerals and deposits them in the ocean. When the water evaporates from the ocean, it leaves the salt and minerals behind. Over billions of years, the oceans became salty. Good deduction on your part!

Edit: See posts by others below.


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

[User] [Star Trek] Borg always ignore intruders unless they're a threat, apparently as a way to conserve resources. But since Starfleet intruders are always there doing something nefarious, like sabotage, have the Borg changed their guest policy at all?

[Assistant]
The Borg don't care about individual ships, at all. They are described as holding trillions of drones over millions of worlds. A singular vessel is about as important to them as a skin cell. At times they've self destructed cubes to remedy a single compromised drone.

As much as the Federation fears the Borg and celebrates every hard won victory, from the collectives point of view, drone harvesting operations against a pretty ordinary target with a single vessel is probably below the overall collectives awareness threshold and happening on entirely automated protocols. The mind of the Borg is literally not aware of the Federation until Voyager intervenes in their war against that extra dimensional species.

You want the Borg to even notice your culture? Be a galactic scale society. That's the kind of target the hive mind is paying attention to. Be a big enough target or threat to even register in the high level mind and you can even force them to the table as Janeway did via a crazy gambit.

This is why we are told sometimes that living with the Borg is possible even though at the federations scale they seem nothing but a wrecking machine. We are something like bacteria to them. To be eaten maybe, studied for advantage sometimes but certainly not talked to. A big enough culture to overcome that and actually talk has options we just don't.

So then, ship board security? Who cares, it's just a skin cell.


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

[User]
How do migratory birds who fly huge distances keep track of all the different predators and edible/non-edible foods they might encounter on their journeys?

Some birds fly thousands of miles on their migrations and it seems to me that these birds would need to keep track of lots of different types of food sources, as well as being aware of threats posed by different predators, and other dangers, along the way. Is it all just inherited memory or instinct? Or do the younger birds just copy the older birds and the cycle just keeps repeating?

Edit: thank you for all the great answers!

[Assistant]
Migration is complicated and operates off several different mechanisms, many of which we don't really understand very well yet. Different species of bird also handle migration differently, so there's no one size fits all answer.

In general, migration is expensive. Predation rates are high and dangers from weather and habitat changes are very real. But if enough birds make it, then it was worth it, evolutionarily speaking.

Some species, like the Great Snipe fly 4,000 - 7,000 km non-stop over the course of 60 - 90 hours, so they wouldn't be worried about food sources en route, just predation.

Long-lived species like storks and cranes learn from older birds. They lead the migrations and stop at the traditional stopover sites along the flyway, and the younger birds learn.

For smaller short-lived species it seems to be largely genetic, in terms of the route they follow and stopping points. As an example, the Northern Wheatear has expanded its territory to cover most of the Northern Hemisphere, but the entire species still migrates to their ancient Sub-Saharan wintering grounds, rather than establish new ones at suitable closer sites.

The migration instinct is strong in avians - even some penguins migrate up to 1,000 km or so.

There is learning and adaptability, both to routes and changes in resources available on those routes, but it's a risky and difficult process overall.


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

[User] [Harry Potter] Why did the Death Eaters attack the Quidditch World Cup? It seems foolish in hindsight, especially since one of Voldemort's active servants put an end to it.

[Assistant]
It was foolish. It wasn't a coordinated attack, just a bunch of rowdy evil wizards getting drunk (or the wizard equivalent) and blowing off steam.

Kinda like those riots that happen after popular Futbol games where cars get overturned, stores get broken into, random fights break out, etc.


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

[User] ELI5: After a penalty in football or basketball, they often show the referee and coach engaged in conversation. What are they discussing since the penalty can't be reversed?

[Assistant] Few things: sometimes the call can be reversed. Other times the coach simply wants explanation of the call. Finally, the coach will often attempt to make a point to the refs which will help them later in the game. Example: Basketball player gets called for a charge. Coach tells the ref that the other team has been flopping and that the call shouldn't have been made. Next time a player falls down, a charge may not be called due to the coach "working" the refs.


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

[User]
[General Sci-fi] Why are large cruisers in space battles always oriented parallel to each other?

In space battles ships have artificial gravity, so isn't up and down always relative? Planets are definitely going to be on different XY planes from each other. That being said, why don't commanders try to approach an enemy force from their underside? Large cruiser ships wouldn't be able to reorient themselves very quickly to adjust, and the only area where I could forsee this being an issue would be when a battle occurs near a planet.

[Assistant] Sensors don't operate on a single plane and have incredible range. There's really no hiding in space either. Any ship will radiate heat and stick out like a sore thumb against the cold black of space. So, you can't really sneak up on anyone unless you're hiding behind something. This means that two big warships in space will typically see each other coming a mile away. Any attempt to maneuver along the z axis will only be met with an a counter maneuver. This leads to the inevitable strategy of "fuck it, will just hit her with the broadside cannons."


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

[User] [General] What businesses would someone immortal own or invest in?

[Assistant]
Things like businesses and currencies are worthless. Even Real Estate is only meaningful as long as the deed is respected, which means one revolution and you lose everything.

If you were truly immortal, the best thing to invest in would be people. Build them up, help them enrich their lives, and it will pay out for you in spades. Do that for a couple hundred years or so and your influence will create a world where the basic quality of life is better than anything you could dream of buying.


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

[User] ELI5: Why is it so much easier to sleep after an orgasm?

[Assistant] Um, it's because your body releases massive amounts of endorphins and dopamine after an orgasm. These chemicals make you feel relaxed and at ease. That coupled with your rate if heavy breathing puts the body into a sleep like state. This will happen anywhere, at any time of day.


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

[User]
ELI5:Why do buses not have a aerodynamic shape like cars?

Is the shape for space?

[Assistant]
Good question! Couple of reasons:

1) Buses tend to not drive all that fast. Aerodynamics are less important at low speeds.

2) As you said, space is a premium on buses. They want to make them are large as they legally can, and they want all of that space to contain room for passengers. Aerodynamic shapes are rarely space-efficient.


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

[User]
[MCU] Why didn't Dr. Strange use the Time Stone when he was on Titan and go back to when Thanos was a little kid and give him a hug?

"It's okay, little one, you have good ideas and everyone loves you."

Could've saved a lot of heartache.

[Assistant]
Rule of thumb: If your question starts with "Why didn't Dr. Strange" then the answer is because he didn't see that in the one future he saw that worked.

I swear this sub needs a meta sticky about it.


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

[User] Could satellites or planets orbit a black hole without being sucked into it and how far away of a black hole would they need to be to stay in orbit?

[Assistant] Yes.  If you replaced the Sun with a black hole of equal mass to the Sun, all the planets would remain in their current orbits. Orbits are determined by gravity, and gravity is dependent on mass. It's just that black holes are so dense that they occupy a small amount of space, which permits the gravity fields near the center of mass to get very strong (because gravity gets much stronger as distance to the center of mass decreases).


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

[User]
[Avengers: Infinity War] Why didn't Proxima just shoot Cap?

Her spear could fire energy blasts.  Why disarm herself in the presence of multiple enhanced individuals in the train station when all she wanted was the Soul Stone?

[Assistant]
Went back and watched the scene to check.

1) First, Proxima seems to be able to call back her spear after it's thrown, as that's what she does after she gets beamed up.

2) Her blasts seemed more for disabling and stunning rather than outright killing. At least twice Scarlet Witch, an otherwise physically un-enhanced human being, was able to take direct, blind-side hits from it and get back up.

Perhaps she imagined this was just some random, ordinary human interloper, and just wanted to get rid of him quickly, and so she threw the spear to kill him instead.


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

[User]
[Star Trek, esp. DS9] How did the Trill figure out the benefits of the symbionts?

It seems to be in the same realm as the joke "it was a brave man who first ate a lobster." At what point do you look at a floating slug and think "I bet if I put that in my abdomen, I can pass my memories on to future Trill."?

[Assistant] 10 billion years ago an amphibian with rudimentary intelligence climbs on the back of a primate with less intelligence and directs it to somewhere they can both find food, 10 billion years later the amphibian has evolved to live inside the primate and the primate has evolved to host it.


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

[User]
[DC] Why is Central City so safe?

Metropolis is a hub for every alien attack on the planet. Gotham is the most crime-ridden city in America. By contrast, Central City has few superhuman attacks, and even those tend to involve few, if any, casualties. It's positively idyllic in comparison. Why doesn't Central City experience the kinds of crazy stuff the other major cities deal with?

[Assistant]
A few reasons.

Firstly, the Flash has less of a hook, for lack of a better word. Superman is the biggest guy on earth and batman has his whole weird psychodrama bullshit. Wonder woman's a goddess and green lantern's a space cop. All draw in drama.

The flash less so. There's no equivalent for "take down a goddess" or "seize the green lantern"  or "rebuild krypton" or so forth- he's just a fast guy. The speed force isn't unique enough to him to justify going after the flash.

This leads to the second point- the flash is probably the nicest of the JLA. He's the friendliest. He's respectful to his foes. And what this means is he has few enemies. Sure Captain Cold and Mirror Master have to fight him because, well, they wanna do crimes and he doesn't want them to. But they're not enemies. The Top isn't  going to track down his family or anything. It's purely  professional.

He's not really done anything to piss anyone off enough to go to the effort of coming for him. The only people who really hate him are the reverse  flashes, and while they do crank up a death toll? Five guys. These days, basically just two guys. They're dangerous, but manageable.

Thirdly? The Central City mob.  Or, as they're usually known, the Rouges. They may look goofy, but they're powerful, clever and they're almost as  invested as the  Flash in keeping Central City safe. They're not like batman's rouges with their random violence or superman's rogues with their alien apathy. The Rogues are actual organised criminals, meaning they're invested in the city being functional, competition being nonexistent and there being no reason for the entire justice league to come calling. Start doing any gotham city shit and they'll shut you down fast.

Lastly? As a lot of who would wins will tell you, Flash is pretty damn good. He normally holds back but when he doesn't, he has perhaps the best power for directly protecting people. Fire a machine gun into a crowd and he can pull everyone to safety before the first bullet's left the barrel. It takes someone very powerful indeed to attack in a way he can't mitigate.

So there you go. Few people are willing to make a shot  at thee flash,  those who do are shut down by the Rogues, and those still going have the death toll reduced rapidly by the flash. Hence central city's saftey!


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

[User]
[X-Files] Mulder finds the ultimate truth: that aliens exist and are running a simulation--that we're the sim and none of us are real. Does he release the truth or become part of the coverup?

He finds hard evidence that the extraterrestrials are running a simulation of all of us and everything else going on is simply to throw us off this fact. The truth could possibly cause mass chaos, such as mass suicides and/or a complete breakdown of order. What does Mulder do with this?

[Assistant]
I think he would go to public no matter what.

BUT...

When Mulder thought that he was being lying to all his life (Gethsemane) he gets really close to killing himself.

If he really believes that he can't tell the truth, it's very possible that he would actually do it.


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

[User]
CMV: Anarcho-Capitalism is a Fundamentally Unworkable System

Change My View: Anarcho-Capitalism is a Fundamentally Unworkable System. For those who do not know, Anarcho-Capitalism (Ancap(s) is how I would refer to them from this point on.) is a political system/ideology that is based of the abolishment of government and it's replacements being private companies. And it's flaws can be broken down into 2 basic categories: Internal & External threats.

1. External threats
       External threats are basically, a different nation invading the ancap nation (Ancapistan.) This basically impossible to prevent, even if citizen or companies had the capital to acquire & maintain weapons of modern war, & are willing to defend Ancapistan, which in itself is questionable, they would unable to stand up to a modern military (I would not debate on Nukes in this debate.) for three reasons: 1. Organization, A group of Private Security Companies could never reach the same level of multi front organization as a modern military, thus causing Ancapistan to be defeated. 2. Most companies lack the ability to operate the logistics required to operate a large scale military force, thus causing a defeat through logistics. And 3. Private Security Companies (Mercenaries) have been historically incredibly unreliable in fighting for the same side, often switching sides if the other side paid more, and so would most likely be true about Ancapistan. All of these reasons would cause Ancapistan to be defeated in any war with a modern military, unless Ancapistan is located in a location that is of no value, which would cause a limited economy to occur, going against capitalism.

2. Internal Threats
       Internal threats can be easily summed up in one phrase <<Companies forming their own governments to extract more profit, defeating the entire point of Anarcho-Capitalism.>> To expand on the idea, lets say we have a Private Security Company called "Blackpond" and Blackpond want's to expand their company, so they drive out their completion with a combination of buyouts, anti-completive & violence so they are now the only PSC in the area, leaving it able to force it's people to pay for "protection" and if they decide to not pay, they would be beaten up by some people from Blackpond, thus essentially creating a corpocracy. Now some counter this by saying "But the people would defend themselves." now I would counter this with 2 arguments, 1. People can take a surprising amount of oppressions before revolting, & 2. even if they revolt, Blackpond could simply partner with those who own heavy military equipment, by exempting them from the protection fee (Tax) so that if anyone revolted, they could only fight with relatively basic hardware, meaning the company, with stuff like Armored Vehicles could simply roll over them

Edit: Fixed formatting error & meant "Workable as Intended"

[Assistant] Anarcho-capitalism is basically feudalism (nobles are business owners, titles are corporations, fealty is subcontracting) and feudalism worked for hundreds of years. There doesn't seem to be any reason why Anarcho-capitalism couldn't work that wouldn't also apply to feudalismunless it were a reason that was inherently connected to modern technology. But in that case, ancap wouldn't be _fundamentally_ unworkable, it would just be unworkable in our present social context.


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

[User]
ELI5: What's the difference between AWD and 4x4?

I recently saw a post about a truck that said that the owner converted their truck from AWD to 4x4. I'm wondering how the two are different because they both follow the principal of all four tires moving. Does one work mechanically different from another? Does one provide more power? How do they work?

[Assistant]
AWD has a fluid coupler between the front and rear wheels so it allows for some wheel speed discrepancy between the front and rear wheels.
Therefore AWD can be used on dry pavement and make tight turns without cause damage to the driveline or chewing up the tires.
AWD is meant to be used in any and all conditions, all the time.

4x4 is selectable between 2 wheel drive and 4x4.  When you're in 4x4 the front and rear drive shafts are "locked" together - turn at the same speed.
Therefore it's not safe to be used on dry pavement and making tight turns (like in a parking lot).
4x4 is meant to be used only in "low traction conditions".

ELI5: 4x4 makes front and rear wheels turn at exactly the same speed - not good on dry pavement.
AWD allows for small differences in speed of wheels so you can use it all the time (like making tight turns, and parking).


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

[User] What complications would arise when carrying a baby and delivering it in zero g?

[Assistant] I will say one practical complication would be the fluids. For anyone who has been present at a birth, let alone a c-section, the fluids in zero G would be a nightmare. You would need a heavy-duty vacuum to try to contain it all. In addition, if you were going to give the mother fluids, you would have to use pressure on the IV bags instead of relying on gravity and a regulator (perhaps you could use pressure and the regulators).


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

[User]
I believe that people who value relationships with animals over humans are dysfunctional to the point of requiring psychological therapy. CMV

I've had discussions with people that say they prefer the company of animals over humans because people are mean-spirited and evil and animals can never be that way.  They give money to animal rescues instead to charities that help humans.  I find those beliefs sick and potentially dangerous and I think those people need professional help.

[Assistant]
It has been psychologically proven that pets do in fact make humans happier. For a lot of people, especially lonely people, if you've noticed, pets fulfil and replace their desire for human companionship. These animals eat with them, run their errands with them and even sleep with them. In the end, they essentially become part of the family, becoming immutably associated as an important entity in their lives. So from a psychological standpoint, one might argue that the unconditional love and support that pets give to their owner might be the extent of the companionship those owners have, or will, receive.

With that being said, these people don't need professional help, but rather healthy relationships from people that care about them.


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

[User]
[Arrival] Can Louise (and the Heptapods in general) ever be considered to be truly 'dead'? Given how they perceive time, does the concept of non-existence exist for them?

I know that they can die/be killed. However, given how they perceive their time-line as one cohesive whole, would they ever really experience 'death'? Louise has presumably already experienced her death - from her point of view she is always dying and always being born, and also always living all the moments in-between. Would death actually destroy her consciousness, or is her life, from her point of view, just an eternal recurrence? No cessation of existence, no afterlife - just one, never-ending experience of a certain slice of time?

Even after Louise's, or a Heptapod's timeline stops (they die), would their experience of that time-line actually end with it? Or does the way they seem to have a unified consciousness that exists across their entire life-time insulate them from such a simple idea of 'death'?

[Assistant]
Of course!

All things *exist* in the present, exclusively. Heptapods (and all things that experience non-linear time) just get the benefit of being able to remember the past *and* future. Death places and upper-limit on how much of the future you can remember.

It's not that they're *experiencing* all moments in time simultaneously, but their memory stretches forwards and backwards through time (which is basically entropy with a trajectory). The lesson *Arrival* teaches us, is to enjoy the present.


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

[User]
[Futureama] Why give a machine that bends girders sentience?

Like, what's the practical application?

[Assistant] Modularity, versatility, economy, reproduction. The programing cards in a robot are replaceable allowing you to change their function if needs be. They can adjust to solve problems that were not anticipated. They can, when not in use, still continue to be productive by feeding back into the economy through their excesses. Lastly robots can make more robots through reproduction.


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

[User] Is there a latency period for human vitamin D production upon UVB exposure, or are skin cells synthesizing vitamin D as soon as exposed? Would we get the same amount of vitamin D from 60 ten-second periods of sunlight as from a single 10 minute period of sunlight?

[Assistant]
Skin cells do not produce vitamins D. The UV light hits cholesterol in skin cell membranes catalyzing its conversion to cholecalciferol which through circulation reaches the liver where some conversions take place and then the kidneys where it is converted to a physiologically active form of vitamin D. Ten minutes of UV exposure either way would produce the same amount of vitamin D.

*edit: changed a sentence for accuracy.


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

[User] [He Man] Why do they fight with swords and maces when they have all kinds of crazy technology and magic?

[Assistant]
Most of the magic does not hit as hard as a dude who can bench press a mountain.

As for the energy and projectiles they seem to use, they travel slow and some of these dudes outrun tiger dragon hybrids.

Given those physical titans I'd consider a sword too.


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

[User] ELI5: Why do Indian reservations still exist?

[Assistant]
Well, why not? People still support the idea. Although conditions on many reservations are bad, most tribes are much happier with the land than without. It's a place where the members of the tribe can be concentrated, and where they can practice tribal law. There's no real substitute for a people to having their own land.

When people criticize the practice of forming reservations, they're not criticizing the fact the tribes got land grants from the federal government, but rather that they were encouraged or forced off the land they already had.


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

[User] ELI5:Why do so many medicines (pain pills, muscle relaxers, antihistamines,etc.) have a side effect of sleepiness?

[Assistant] All of the types of medicines you described work by basically stopping your body from doing something it would normally be doing, often by interfering with the ability of your nervous system to communicate the messages necessary to do it.  A side effect of that can be to generally slow down your nervous system overall, which manifests (among other ways) in you feeling sleepy.


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

[User]
ELI5: How is calling internationally from skype to phone cheaper than calling through your regular service provider?

I am an Indian and I was browsing about ways on how to call internationally and how much would each of those methods cost. As compared to price rates of the regular service providers, calling over skype was way cheaper and in some cases free. How does this happen, when essentially the same end result is obtained.

[Assistant]
To explain it real simple.

Calling goes over the phone line.

Calling over phone lines over long distance requires a lot of connecting and re-connecting of different networks.

(i'm quite sure this doesnt actually still requires connecting but phone companies still charge a lot extra for longer distance calls)

Skype goes over the internet.

The internet is connected to the entire world, so it doesnt matter if you're 1 street away for litteraly on the other side of the world.

So yes, calling long distance over skype (or other simmilar programs) is much cheaper.


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

[User]
On the atomic level, what is happening when I spill acid on myself? Is it the same with bases?

Thanks in advance!

edit: also, are there any other "corrosive" substances that are dangerous to humans other than acids/bases? The only counterexample I could think of was chlorine gas, but that's acidic too...

[Assistant]
The process is called hydrolysis.  The name is the same for acids and bases, however the reaction and end-product can be different.  It's called hydrolysis because water is involved in breaking down the molecules.

Proteins hydrolyze easily.  This is one of the reasons animal tissue breaks down so easily under alkaline conditions.

edit:  Any highly reactive chemical can cause chemical burns in a similar way, however it is not called hydrolysis because water is typically not involved.


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

[User]
ELI5: Why aren't ground water reserves filling up when it is raining, doesn't the water just seep through the soil back into the reservoirs?

Does the rain coming from oceans resupply the water flowing into them from rivers and if not how ARE there still rivers to flow? Shouldn't they have drained?

[Assistant]
Geotechnical engineer here:

When it rains, some water is evaporated, and some of it seeps down into the ground, through the pore spaces in soil, and through cracks in rocks. It keeps going down until it hits a confining layer like clay or bedrock. At that point, the water starts to pool up.   It can still flow into the clay and into the cracks in the bedrock, but this is at a very slow rate. If the influx from rain and snowmelt is higher than the the amount that slowly seeps deeper into the ground, then the water table will rise.  If the water table rises above the surface, then water will start to pool on the surface.

Notice how lakes are usually at a low point in elevation. This is because the surface of the ground is lower than the water table in that spot.

If it is only raining in one spot, the water will spread out laterally to drier spots, like how water spreads out when you pour it onto a table.  Water spreads out a lot slower in soil than in air though, so if you have very intense rain in one spot, it can start to flood before it starts to spread out.
The opposite effect can happen if pump too much water from a well in a short amount of time:  It can lower the water table in that spot, and it could take a while for the water to flow laterally and raise the water table back to where it was.

There are a lot of other complicated processes that can come into play, but this is the basic principle.


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

[User]
Do trees die of old age?

How does that work? How do some trees live for thousands of years and *not* die of old age?

[Assistant]
The Giant Sequoias continue to grow during their lifespan of a few thousand years.  However, as they grow taller and taller, their root system does not grow deeper, it grows wider at ground level.

So that particular species of tree doesn't 'die of old age', but over time, it's growth naturally decreases its stability, making it more and more vulnerable to falling as a result of winds.


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

[User]
ELI5: How can hospitals charge as much as they do?

I read and article on Reddit earlier today about a lady who was hospitalized for like 10 days in a coma. Her bill came out to close to $250,000. How is this even possible or legal? How do they justify thess ludicrous prices?

[Assistant] They have large overhead that not only includes the running of the building, paying people, but massive malpractice insurance rates and other things. This is also a free capitalist country and you can charge whatever you want for any product or service and either people will pay it, or they wont. If you do not pay you will either have to lower your price, or go out of business. With hospitals most people pay.