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How do clothing manufacturers make up the losses from selling different sizes of merchandise for the same price? | [
"There's not really a loss from that, there's just less of a gain. If the cost to make a medium shirt is $20, less than $2 of that is actually in the materials of the shirt. Probably even less than that. The rest of the cost is the machinery, the workers' wages, the rent on the factory, insurance, and a dozen other... | [
"Each culture has an 'in' to a particular business in each area. So, one Korean family will come and open a dry cleaning business. When their cousins come, they will tell them the tricks of the trade and the regulations and have the business model set, so their cousins open up another cleaning business one town ove... |
Why does boiling contaminated water make it drinkable? | [
"The heat kills bacteria and other potentially icky things in the water. It's not fool proof but it's better than nothing."
] | [
"As others have mentioned, food spoilage is ~~about the toxins bacteria create~~ not necessarily about the bacteria themselves, but can be about the toxins they create. Cooking removes the bacteria but not the toxins. A food item will be just as \"spoiled\" (the same amount of toxin) but the *rate of spoilage* woul... |
What does it take to convert matter into energy, and would it cause an explosion? Why, exactly, would it cause an explosion if it would? | [
"the most common method to convert matter into energy is combustion ( burning it ), this reaction produces thermal (heat) energy, and a small amount of kenetic (movement) energy from expanding gases. in a car those expanding gases are used to push the pistons in the engine. in a steam engine the thermal energy is u... | [
"This is a small complaint, but you don't have a theory about antimatter. You have a conjecture. I don't know enough about the topic to say if it has any possible credence or not, but a theory requires a lot more work than \"hmmm, maybe it's this!\" This is not supposed to discourage you wondering or asking, just h... |
Why do buses not have seat belts? | [
"Compartmentalization. The high seats prevent you from flying through the windshield. Also, they hurt fewer people than seatbelts. Also, a bus is a giant ridiculous vehicle, in most accidents it comes out the decisive winner with little or no damage even from a hummer. Details are here: _URL_0_"
] | [
"It takes a while to implement the changes. How would you like it if the law changed overnight and you had to pay fees/go to jail next day without having a chance to adapt yet."
] |
Why did so many Vietnam protesters blame soldiers who were drafted? | [
"* they needed someone to blame...emotions ran pretty high, and returning soldiers were a very visible and accessible part of the war * part of the outrage was due to alleged war atrocities, which some, albeit very few, soldiers participated in * many of the protesters dodged the draft and suffered for it, and felt... | [
"Because the technology was in it's infancy in 2014. Deep packet inspection was just being pioneered by the Chinese. Once it became possible to record your every website click the first ones to do it were the NSA. But now that shit's commercial and cheap enough and intelligent enough to make life *really suck* if y... |
Why can I see in low light so much better than even a high-quality camera? | [
"To add more knowledge to the answers already provided: Your eyes secrete a chemical called [Rhodopsin](_URL_0_) (and others) that drastically increases its sensitivity to light. It takes about 30-60 minutes for your retina to be fully saturated with this, but can be burnt off by light in an instant. This is one of... | [
"This is a more scientific answer than it sounds: it's all in your head. Try having a friend hold a pen there randomly half of the time. You guess when it's there, the more you guess the closer to chance you should get."
] |
What would happen if you drop an object in a vacuum with infinite depth and with a consistent gravitational pull? | [
"If you subject an object starting from rest to a constant proper force, [this](_URL_0_) is what will happen. It will asymptotically approach c but never reach it. From the point of view of a stationary observer, the acceleration of the object will asymptotically approach zero so that its speed never reaches c."
] | [
"The \"proper\" answer requires a good understanding of graduate-level mathematics and physics. But an ELI5 answer is basically that if you take the equations we use that describe general relativity, and the equations we use that describe quantum mechanics, and try to apply them to the same situation (such as the s... |
why is a chip on a credit card considered ‘safer’ than swiping the magnetic strip? | [
"Magnetic strips can be much more easily duplicated than the chips. The strip can be duplicated just by reading the swipe, since the data it gives *is* the data it has. The chip, instead, gives an encrypted code based on what you ask it by combining the value you gave it with a secret one it has, and even if you as... | [
"Food takes time to reach the stomach, and you'll notice if you eat and then wait you'll be less hungry. Chewing more simply takes more time to do, and so you get full with less food"
] |
Why are lobbyists allowed to pay Senators etc huge amounts of money to get what they want - why isn't it seen as bribery? | [
"Because those same senators write the laws saying that it's not bribery. And they're not really paying the politicians directly. They're doing things like paying into the politician's re-election fund or other \"campaign contributions\"."
] | [
"Because what's considered \"high amounts\" of things in air is actually quite a tiny amount. For example, pollen count is measured in grains of pollen per cubic meter of air, and the websites that I see to track it have \"very high\" pollen levels at around 10. That's 10 grains of pollen per cubic meter. Hardly so... |
What would 'Spanish' people have looked like at the time of the Moorish conquest? | [
"I can't offer a complete answer to your question, but I can refute your hypothesis: the Visigoths did *not* drastically affect the Spaniards genetically, linguistically, or religiously. There were relatively few Visigoths, and they did not integrate well with the native Roman Iberians. Just as Iberians continued s... | [
"Follow-up/related: Do we have any idea how prevalent the Classically stereotypical physical traits for each group (e.g. big strapping blond-haired Dorians) actually were in those populations?"
] |
If all drugs were legal wouldn't criminal organizations still have an advantage since they don't have to pay min-wage, taxes, and can sell at a cheaper price? | [
"For a possible parallel, look at alcohol. Some people in rural areas still distill and sell moonshine, both as a sort of \"Screw you\" to the government, and also because it's strong and cheaper to buy with no taxes attached. However, bootlegged liquor is many, many orders of magnitude less popular than it was du... | [
"The more money that is in circulation the lower the value of each denomination of that money. So a dollar today may get you a candy bar, but after the government prints a whole bunch of money that same candy bar may cost you three dollars."
] |
Why does stubbing your toe hurt so much in comparison to other "minor" adventures? | [
"Your toes have a lot of nerves clustered in a small area, more sensation = more pain. Your toes also have fairly little padding compared to the rest of your body, so there isn't much there to absorb the impact."
] | [
"Our brains didn't evolve with cars in mind. They evolved with, like, being hunted by a jaguar (or whatever) in mind. So your brain doesn't know what to do with a car. It thinks hey, we're sitting, our body's not really doing anything physical, there's very little activity or stimulus... this seems like a good time... |
If meditation is good for the brain, is the opposite of mediation(chaotic, unfocused thoughts) bad for the brain? | [
"I think you're going to have to explain your premise before anyone can answer your question. In what way do you think meditation is \"good\" for the brain? Do you have a source that states that meditation is \"good for the brain\" so we can form an objective definition for what that might mean?"
] | [
"Your eye has muscles that adjust the shape of the lens. This changes the focal point, optimally so that the light coming from part of an object converges on part of the retina, the image is 'in focus.' These muscles can essentially focus automatically, but you can control them. So if you are relaxing those muscles... |
How much difference does 0.3 GHz really make? | [
"I'm not a computer expert but the answer to this is basically the same as \"What difference does 20 horsepower make between two sports cars\". Basically in either sports car, it's hard to notice a difference when you're just going down the road in a 30mph zone. But when you put the pedal to the metal and ask it fo... | [
"You might want to get in the habit if finding out how dangerous something is before you do it, not after. Don't inhale or ingest it, don't put it on your skin. You should live. The gamma and beta aren't anything crazy. That is normal background for some places. 1 millisievert/h is hot, and the reason you don't wan... |
Why does salt make ice so much colder | [
"Pure water has a freezing point/melting point of 32 F or 0 C. However, there is also a property called 'Latent Heat of Fusion' which describes the amount of energy needed to turn a solid into a liquid without the temperature changing. When you dissolve something like salt in water, it pushes the freezing point qui... | [
"Crystals are simply an ordered arrangement of molecules or atoms in a repeating lattice. The term \"crystalline\" doesn't refer to something intrinsic in NaCl, but rather a property of one way you can make solid NaCl. Getting crystals to form is a bit of an art in chemistry. In principle, if you have a pure substa... |
Did Saddam Hussein try to nationalize his oil before 9/11? | [
"Iraq nationalised its oil industry in 1972 and joined in the 1973-74 Arab oil embargo against the US and selected allies (there'd also been an earlier rather ineffectual one in 1967). Iraqi oil exports were severely limited under UN sanctions in 1991-2003 and were briefly suspended by the regime in 2002, but I'm u... | [
"Hi there -- while we've approved this question, we would like to remind potential respondents of our [current events](_URL_0_) (AKA \"20-year\") rule -- it's fine to discuss events through 1997 (inclusive) and their effects, but not events after 1997. Thanks!"
] |
Why does local news look so much shittier than national news? | [
"National news shows are watched by millions of people, so their budget is simply much much higher."
] | [
"Everybody's front page is different, depending on which subreddits you subscribe to. If you never subscribe/unsubscribe manually or you view reddit without logging into an account, you will see the default subreddits. The default subreddits are determined by reddit staff (presumably based on quality & popularity).... |
I keep hearing that Voyager will take 10,000 years or 100,000 years to reach the closest star. Is it actually aimed towards a star or is it just going in a random direction? | [
"Voyager 1 will pass within 1.6 light years from some nameless star in Camelopardalis. Voyager 2 will pass within 1.7 light years from 248 then in 300,000 years pass 4.3 light years from Sirius. So really, they're not aimed at anything. [Here is my source at JPL](_URL_0_)."
] | [
"Most of the articles you come across are often the first step in the long journey towards production of a safe and effective medical treatment. The first step - discovering the possibility of a new kind of treatment - is really exciting as it allows speculation of some pretty amazing, albeit potential, results in ... |
Why are most babies born with blue eyes and only a few with a darker color? | [
"The iris appears blue instead of white because parts of the cornea absorb and scatter white light in a fashion that what comes out appears blue. While the Iris is white in itself, any light which escapes the iris will be of blue wavelength, giving the iris a blue appearance. Most babies are born with blue eyes bec... | [
"It is down to the combination of the genes you get half the genes from your mother and half from your father but those genes are an almost random selection of those genes which go to make up each so can be combined in trillions of different ways. Like saying you get half a pack of cards from one parent and half fr... |
How did diabetics check their blood sugars before personal glucometers? | [
"Glucose monitors have been around for over 35 years. They were just bigger and slower. Before then it was controlled through highly restrictive diets and insulin and oral medicines and everyone kinda hoped for the best. Bloodwork was limited to labs and hospitals."
] | [
"On a slightly related, yet mostly different note - where did people keep their money back in those times? For example a Roman solider gets his pay, where does he put it that isn't just easily stolen by somebody walking into their (potentially) unlocked house and taking it?"
] |
Could water clouds form on a planet with no/barely any liquid surface water? | [
"Water ice clouds have been [observed in the atmosphere of Mars](_URL_0_), imaged directly from spacecraft on it surface."
] | [
"Would depend on what the weather is like and how big the methane lakes are. Not sure but interesting question."
] |
how does naloxone work? | [
"The way I'm understanding it is it can block and reverse opiates from doing their thing. Both the opiates and naloxone fit a particular receptor in the nervous system - like a key in a keyhole. Once the molecule attaches, it triggers a response or \"action\". The right key will start the car. In the case of the op... | [
"I could try to explain it to you, but this video is all you really need: _URL_9_"
] |
Why did the Nazis make caricatures of the KKK painting them as evil and bad? | [
"there's a pretty good thread on this [here](_URL_0_) with responses from /u/Georgy_K_Zhukov and /u/kieslowskifan."
] | [
"This is a fun question. And it mostly has to do with cartographers and how they built /drew maps. Plus a little bit of British imperialism. Most of the early cartographers were employed by the rich Northern European countries to make maps of their country and the new world. So they put their native/home country fr... |
Why will the baby born with 13 fingers have to undergo operations to remove 3 fingers? Why can't it keep them all? | [
"The baby needs reconstruction surgery to form a thumb on each hand so he will be able to grip properly. Too many digits will also cause a problem with normal gripping. I understand he also has 2 palms. Hand surgery is very complicated and difficult so he will need a very experienced hand surgeon for this. I hope t... | [
"Labour is expensive. P/D shrimp (peel and deveined) are more expensive than unpeeled. Paying your cooks to pinch tails is also expensive,a nd there's far too much work to be done to waste time doing it. All those costs factor into the cost of the dish (usually about 17-20% of the cost of your dish is labour cost).... |
How many WWII draftees were working in the CCC before they were drafted? | [
"The Civilian Conservation Corps was far and away the largest of the make-work projects during the New Deal. It was operated by the US Army, since they were the only government organization in 1933 that had the ability to handle such a large number of men. The CCC workers were civilians, so the army could not boss... | [
"First some major points, the Joads were farmers/unskilled workers. These employment groups were hit hardest by the depressions as the industries that used them cut production while farming which had never enjoyed the boom of the 1920's collapsed. There were little employment opportunities for such people in most o... |
What makes smartphones cost so much more than even a decent desktop or laptop? | [
"It is a lot more difficult and expensive to make electronics really really small. That's also why a desktop computer of the same basic specs will cost less than the laptop. It's also a phone - so you have to add in those components."
] | [
"Here's a pretty good explainer. _URL_0_ Basically it comes down to different memory, different promises (reliability and service life), and different marketing."
] |
You have 2 parents, 4 grandparents, 8 great-grandparents, and so on. Go back 24 generations and one person today has 16.8 million direct relatives alive at the same time. At some point in history, one person alive today has enough ancestors that would exceed the population at that time. How? | [
"Those 2^n people are not all unique - one person can take up many \"slots\". Let's say your parents were third cousins. That would mean they share 2 of their great-great grandparents. Those 2 people are 4 of your great-great-great grandparents, appearing once on your mother's side and once on your father's side. ... | [
"Leopold II, the worst person in history, owned Kongo Vrijstaat (Congo Free State). A colony 2,344,858 km2/905,355 sq mi - roughly 24% the size of the US. At the start it had a population of about 30 million (~1,7% of world pop.). When he was forced to turn it over to Belgium (of which he was the King) 16 million r... |
What does it mean in betting to cover a spread? | [
"Broncos and Jaguars are a good example for this. The Broncos are really good, and the Jaguars are not good. So, it's very very likely that the Broncos will win. So there's not much point for someone taking the bets to base it on who will win, because then everyone will just bet on the Broncos and they'll all win a... | [
"Lots of airlines use the hub and spoke model. Rather than have a flight from every city to every other city, they have flights from the small cities to a few big cities, called \"hubs\". You then fly from the hub to your destination city, or perhaps to another hub, from which you fly to your destination. So let's ... |
I'm an in-house translator who may soon be out of work. Is historical document translation a thing, as in people will pay to have it done professionally? | [
"Speaking as a broke grad student and friend of many more broke grad students, historical document translation would be AMAZING, but there's absolutely no way I could afford it."
] | [
"A follow up question for when this is answered: if it is possible to make one, would it be possible to mass-produce? I’ve heard of Roman “fast food”, so the concept was there, but if someone went back in time with the knowledge to do so, would it be achievable to get a Roman McDonald’s chain up and running?"
] |
The difference between AMD and Intel processors. | [
"The simple answer is that although they look similar on paper they perform very differently. The Intel processor is much faster than the AMD one in this case and therefore Intel can ask more for it. For their top of the line processors Intel always charge a huge extra premium for their best of the best stuff. A lo... | [
"I thought it was explained pretty well by this old tek syndicate video _URL_1_ Definitely worth a watch!"
] |
How do leggings keep somebody warm in the fall and winter months? | [
"For me it's two words: Fleece-lined. Marvelous, I tell you. Keeps you kinda toasty even if you're in the Midwest like me. Sometimes she might be wearing an extra pair."
] | [
"Imagine your body is a phone. Not a Samsung Galaxy S56XL, just a regular one. You go and open 30 apps and the phone suddenly starts slowing down, right? Well, now imagine the common cold is a VERY consuming app for your cellphone, some kind of new Fortnite 2 game or whatever. Your body doesn't work as well when yo... |
Why do mouths go dry before/during giving a performance you're nervous about? | [
"During the flight-or-fight reaction and the release of adrenaline, which comes out when we are nervous, the saliva glands are inhibited."
] | [
"Think of your brain like a billion streams of water that flow over the surface of a rock. The more you use a certain stream, the more \"powerful\" that stream becomes by digging away that rock. Now even if you have a nice dug place for a stream, sometimes randomly that stream won't have needed to flow for a while ... |
How did cameras on spacecraft film, and transmit data before we had digital cameras? | [
"Radio waves, just like we still do today. If you want an example, think about how television worked in the 1940's and 1950's. Take an image and transmit it via radio to a receiver."
] | [
"Why, yes! We do: _URL_0_ (crappy example youtube) edit: Extreme high resolution often requires long acquisition times (making videos difficult) and for many applications you do not want any movement (which makes videos really boring)."
] |
Why did the average amount of days soldiers spent in combat increase so rapidly in Vietnam, (240 days,) in comparison with World War II? (10 days.) | [
"Could you perhaps present us with your original source so we can see what the author writes about it? I *think* I know the answer, but I would like to know what exactly the author wrote. Also, could you remove the bonus question? We do not allow discussions of events after 1993."
] | [
"One thing to point out is the terrain. Iraq is in the populous parts of the country pretty flat, with a semi good road network across the country making it easy to move people around, and larger cities and towns to organize around. Afghanistan is some of the most inhospitable terrain on earth. With little nation... |
What happens when you use a higher resolution wallpaper on a 1900x1200 monitor? | [
"Yup! It just gets scaled down. The reverse is also possible. You can also use SVG files as a background, which have no fixed resolution at all."
] | [
"There are a lot of people in the world who don't care about laws, or the laws of other countries, or the property rights of other people. For example if you stole a piece of art from someone in England that a wealthy member of the royal family in Saudi Arabia wanted they probably don't care at all that it was stol... |
Why do the nets in pro basketball never get stuck? | [
"really thin light weight material. Social basketball stadium nets have people stretch them by hanging them etc."
] | [
"Back then people still needed jobs, now they dont and can practice harder for longer. And science helps by showing then methods on improving motions. You cam find cool videos on youtube"
] |
Can small organisms that bite (such as spiders or some forms of insects) detect that they're standing on a living organism? | [
"You'd be surprised at how good these animals are at knowing when they are close to a meal. Don't forget that things like mosquitos (and their ilk) have the advantage of millions upon millions of years of evolutionary selective pressure that have made them into blood sucking machines. They are extremely good at det... | [
"It tracks mouse movement. If it was a bot it would immediately click the checkbox after it was loaded. You as a human have to move your mouse cursor to the checkbox and this movement is not in a straight line. So basically they just check mouse movement and time between checkbox being rendered and when it is click... |
Wouldn't splitting water molecules result in less water available to drink? | [
"Technically, yes, splitting water molecules to get hydrogen is using up water. And technically, yes, you can react hydrogen with oxygen and get the water back. But considering the quantity of water on Earth, humans could create a great deal of hydrogen without having a significant impact on the supply. Bear in min... | [
"very simple, Air is a horrible transfer medium for energy, Water is a good tranfter medium for energy. It takes longer for the energy in the air to flow to the ice cube then the energy in the water to flow in the ice cube, When when there is steam in the air, its still maybe 50% humidity compared to 100% humidity... |
What kind of techniques are best for counting the number of protestors in Hong Kong? Or any crowd for that matter? | [
"Draw an imaginary square and count how many people fit inside, then count how many squares are in the crowd and you a pretty good guess"
] | [
"There was a great short YouTube documentary about the company that does this for the Premier League posted in r/soccer a while back but I can't find it right now. Basically there are a bunch of guys who sit around and watch certain games on computers with special software that lets them keep track of all this stuf... |
Why does using cruise control hurt your fuel economy? | [
"On a modern car, cruise control should be more economical. One of the problems with cruise control is that it can't see the road ahead. So, the car will change gears on sudden inclines or declines too late and will, therefore, use more fuel - because of inefficient gearing."
] | [
"Our brains didn't evolve with cars in mind. They evolved with, like, being hunted by a jaguar (or whatever) in mind. So your brain doesn't know what to do with a car. It thinks hey, we're sitting, our body's not really doing anything physical, there's very little activity or stimulus... this seems like a good time... |
Dog species in ancient Rome | [
"All domestic dogs are the same species. It's better to say \"breed\" of dog."
] | [
"Might be a bit earlier than what you were looking for, but the guardians of the Byzantine Emperor looked something like this: [Varangian Guard](_URL_0_)"
] |
Under what authority and to what limit can the US go into foreign countries and seize non-US citizens for crimes against the US | [
"Strictly speaking, they can't. Such things are only possible with special treaties between 2 countries. Usually those include that the US can ask government XYZ to extradite a person. If they agree, they either bring the person to the US, or allow to US to go there and get him. If not, nothing happens, such is the... | [
"There is precedence in the concept of tortious interference. Let's say you arrange to sell some product to a potential buyer. But, before they actually buy the product, they bow out of the deal. You find out that some third party was spreading rumors or lies about you, and that directly led to the buyer not follow... |
How did dolphins breathe while sleeping BEFORE evolving unihemispheric sleep? | [
"Likely, they weren't 100% aquatic until a mutation that allowed unihemispheric occured. IE, they couldn't move into the water full time until the sleep issue was 'solved'. Sometimes, a series of beneficial mutations have to occur, the occurence of one making a subsequent mutation that would have been deleterious, ... | [
"We don't require a pillow. You can sleep on a flat hard surface with no pillows at all. Comfort we have now is a modern invention."
] |
I'm skinny and I had to move a heavy sofa up the stairs. After that my hand muscles felt tense. Doing some hand movements (like brushing teeth) felt "unresponsive" and not precise for a while. What is actually happening? | [
"You used muscles you do not normally use to a degree you do not normally use them and you stressed those muscles. It is the exact same thing as happens when you work out and are sore afterwards."
] | [
"Your muscles get somewhat paralyzed when you sleep. Parkinson disease sufferers muscles relax when they sleep."
] |
If diet soda has no sugar, what is it that still makes it bad for you? | [
"There is nothing inherently bad for you about diet soda. It isn't ideal if you're trying to lose weight, because drinking it may stimulate your appetite. But as part of a healthy diet there's nothing wrong with no-calorie sodas, or even regular sodas. The regular ones just have a fair amount of sugar in them, whic... | [
"The carbon dioxide, the bubbles, is a gas at RT. Pouring it into an empty glass means the liquid falls from a higher distance, when it hits the bottom of the glass the impact provides enough energy for the gas to escape. Not only does the liquid in there reduce the distance but also softens the impact. If you were... |
If prehistoric humans didn't shave their beards, how did they eat? | [
"You can make a stone knife sharp enough to skin a rabbit. Cutting hair isn't that hard, and options such as braiding or binding also exist."
] | [
"Hi OP, this is a cultural question, so it would greatly assist anyone considering answering if you could specify which culture you're asking about. For example, the name of a cultural group / country / geographic region, plus a rough time period. Otherwise, this question is simply too broad, as it encompasses almo... |
What happens to throwaway accounts? | [
"I think many don't actually throw their account away, since their only reason for creating one is to keep their main account free of the association with what they're posting/saying on their throwaway account. Most aren't ducking the authorities or any real investigation. To my knowledge, there's no \"throwaway\" ... | [
"You may want to browse /r/theoryofreddit , where they do experiments on things like this."
] |
How am i able to think about two things at the same time? | [
"Althoguh not an entirely scientific response, people can generally \"focus\" on one intensive thought process while also being able to perform a more \"automatic\" thing. Take your example of singing the song: if you know the song very well, the words just come naturally and doesn't cost a lot of brain processing,... | [
"You might have an eye issue that causes each eye to see different wavelengths as different distances from you. I know some one who would have that issue with red and blue lights on top of buildings that way."
] |
How does the acid in lead acid batteries not consume the lead? | [
"It does- in fact, that's how it works. It turns it into lead sulfate, and when all the lead has been so turned, the battery is dead. Charging a battery gradually turns the lead sulfate and water back into lead oxide and sulfuric acid."
] | [
"Battery technology has advanced by leaps and bounds in the last 20 years. You just think it hasn't encase the physical size is still same in cell phones. That's due to increased demand by the electrical components. The capacity of those same size batteries are worlds appart. Every year the same size battery gains ... |
Why do all curly fries have that similar seasoning? | [
"Curly fries as a frozen product (IQF) were first mass produced by Simplot, who uses a specific seasoning blend. Once copycats came along, it became the seasoning of choice due to popularity."
] | [
"Read Bill Bryson's book, At Home. There is pretty much an entire chapter on the history of condiments and such. Fascinating."
] |
What does black hole at center of the Milky Way move relative to? | [
"It rotates relative to me. There is no absolute frame. So scientists will pick one that makes the math easier."
] | [
"Any physically straigth line will always appear arc shaped if it covers long enough area of your vision. Its just our brains can make us realise they are really straigth if there is enough context. For the case of milkiway center there isnt. Cameras can cause further confusion. Its like inverse version of the prob... |
How do both fusion and fission release energy? | [
"Different atoms. Fission energy comes from splitting apart heavy atoms, for example uranium or plutonium. When they split, they actually former lighter atoms as well as releasing energy. Fusion is the act of forcing together light atoms, specifically hydrogen, to form heavier elements. You're absolutely correct th... | [
"there are differences in the way that the rock Sheers. Megathrust vs Strike-Slip In a Megathrust Earthquake (the sort which cause tsunamis) the fault breaks vertically and the seafloor is lifted or dropped by several feet or meters around the fault. Moving the Sea floor up or down moves the entire column of water... |
why is carbon dioxide the go to gas for soft drinks? | [
"Don't forget solubility! CO2 pressurized in water will form some carbonic acid. This coming out of solution as you warm up the soda in your mouth is part of the fizziness you feel. O2 and N2 would be a lot less soluble, so there would be less fizz. [Here are some actual numbers for solubility](_URL_0_). Other gase... | [
"some restaurants it actually is but 1) it sells better if there is a visual stimulus such as having a dispenser. 2) making their own tea is easy and MUCH cheaper than paying to have “Brisk” ice tea in a soda dispenser. This way they can brew their own and make more money. Source: was fast food manager in past li... |
What is cosmic radiation and why is it harmful to life? | [
"Cosmic rays originate from outside of the Solar System, and it's essentially high-energy radiation coming from space. Because of how powerful it is, it's not only bad for life, but it's also bad for electronics because it can alter circuit components in them. As for life, it's the main barrier for space travel bec... | [
"When Einstein was first formulating his theory of relativity in the 1910s, he worked through some of the equations and they produced a really weird result - they said that the universe should expand. This didn't make any sense to him (understandably - it's a bizzare result) and he assumed that there was a mistake ... |
Why does a pot of water make noise as it nears it's boiling point? | [
"The water heats up from the bottom. It boils and turns into a steam bubble, which rises. As the bubble runs into cooler water above it, it releases its heat, turns back into water, and collapses. The sound is the collapsing bubbles. When the water heats up enough that the bubbles make it all the way to the surface... | [
"You've got a tube that connects your inner ear to your throat called a Eustachian tube. Normally this tube is pretty much open, except for a 'door' on the throat end to keep stuff out. When you've got a cold, the tube can get infected and it gets swollen, so even if the 'door' opens it can't equalize pressure bet... |
On a scale of Hertz - particularly audio - what does it mean to be at 0Hz? Is a minus Hz or negative frequency possible, and if so, what are they/what are some examples of them? | [
"A hertz is a cycle per second. Audio is compressed air, in some periodic way, so for 440hz for example, the compression change from fully compressed to fully decompressed 440 times per second. Zero hertz means zero cycles per second, which means nothing is changing. Essentially this means no sound. Negative hertz ... | [
"Others have answered for ambiguous, but here's the closest I could find for no gender (or sex, if you will) _URL_7_ But apparently you can't get any more genderless than immature female with no gonads...that's the genetically default body plan that develops when you leave out all the hormones."
] |
Why is it that most "popular" music comes from English speaking people? | [
"That depends on the country. A majority of those numbers come from sales. In a consumer rich country like USA, you will see a sky rocket of popularity in music that consumers can enjoy. In Mexico you may find more traditional music to be more popular, where the majority of the population does not speak English. Ja... | [
"Lower right corner, there is your tray, click on the icon that looks like a keyboard, and change the setting to US English, or just US. If you don't have this little icon, look for a little taskbar that can be anywhere on your screen, usually at the top. Change it to US settings. It happens whenever you change yo... |
How is the bee queen chosen? | [
"by chance really. when the hive is in need of a new queen, larvae are feed exclusively on Royal Jelly (all bees get fed with royal jelly but queens are fed exclusively by it which allows them to mature) by the worker bees. and from there it's up to chance. It's first come kill all. The first \"queen bee\" to hatch... | [
"Woo! This means more to me than receiving an entire year's worth of tribute from Tochtepec! Thanks to all who voted and to all the other candidates who wrote up fantastic answers."
] |
why people can’t sleep for a couple years to awaken with enough energy to stay awake for just as long? | [
"A main purpose of sleep is to clean up chemical waste products that your brain cells make constantly. If you stay awake for a year, without any sleep time for clean-up, you will in fact die long before the year is over."
] | [
"Probably because with each year that goes by, you have a longer frame of reference to what time feels like? I don't think I phrased that well, but what I mean is that if you are 5, one year is 20% of your entire existence. If you are 50, one year is 2% of your life. So, to get the same feeling of \"long ago\", it ... |
How are anaesthetics made? | [
"There's a bunch of different, completely unrelated drugs used in anesthesia. Some are opiates, some are benzos, some are something completely different. Novocaine, a topical anesthetic, and its derivatives are based on cocaine. The term doesn't describe a mechanism of action but rather is a term to describe the en... | [
"Definitely possible. Various FDA-type labs have the recipe surely. Disclosing it is another matter. \"Secrecy of recipe\" is a marketing gimmick - to keep the \"special\" image alive."
] |
Why is it that some people retain accents after learning a language while others don't. For instance my girlfriend was born in Iran, moved to the US at 12 and has no accent whatsoever. While others have lived here for 20 years and sound fresh of the boat. | [
"People's brains just work differently. Variables include, but are not limited to - Age, natural linguistic abilities, desire to change, use of language(s), etc. I would suspect those that maintain their accent tend to use their native language when speaking to others who also use speak that language natively. Wher... | [
"Unlike today, circa 1965 there were probably few, if any Vietnamese Americans in the US military. Unlike Chinese, Japanese, or Filipinos, there was not a sizable population of Vietnamese living in the United States in the years before the Vietnam War. The large number of Vietnamese living in the United States, Au... |
Would driving/moving at the speed of light feel the same as going 500 mph on a plane? | [
"You only feel acceleration. If you're inside a sealed ship moving along with it, you cannot tell your state from one that is at rest. This is one of relativity's fundamental assumptions."
] | [
"Doppler effect. Think of sound as being invisible waves emitting from the source. Imagine an engine sitting still 100 yards away. It emits 1 wave per second. This is the \"normal\" sound. When the engine is traveling towards you, it is still emitting 1 wave per second, but between each emitted wave it is getting c... |
Why do Operating Systems need increasingly more minimum hardware requirements when their primary function seemingly continues to be file organization? | [
"[DOS](_URL_1_) and [Windows 7](_URL_0_) both organize files; which would you prefer to use? The increased requirements come from adding features, some of which you might prefer not to use and some of which you might use without really knowing it (compare plug-and-play support between Windows 7 and, say, Windows 98... | [
"Specializing helps with optimization. Cows can't eat meat, but their teeth and multiple stomachs are ideal for eating grass. Humans have to have sharp teeth for meat and grinding teeth for plants and our digestive system is inefficient at processing plant matter. Versatility is obviously useful, but there are trad... |
How much lower can a person comsume from 1200 calories a day and still be healthy? | [
"If you have adequate fat stores, water and take a multivitamin, zero kcal. People talking about starving are wrong; if you have fat on you, it will be used instead. You're starving when this is almost all gone. A lack of food is called hunger."
] | [
"It really depends on what type of components are in the computer and what sort of power state they are in during the break (eg. standby mode, or just running with a screen saver). But in general the components in computers don't work like that. They use relatively constant amounts of power. Using a theoretical com... |
Steam files being downloaded are the full size of the game before finishing | [
"It's reserving the amount of space it will need. It's done so that you don't accidentally fill up the drive before it's finished, preventing it from finishing."
] | [
"To the first point: for whatever reason, and there are loads of analytics to back this up, most people don't want YouTube videos all the way through, especially when they're over about 10 minutes in length. So Google realized they could save bandwidth by greatly reducing the amount of buffering they did for videos... |
How can a high-wealth individual effectively drop their income tax rate to zero? | [
"One of the more effective ways for a very high wealth person to have their income tax rate go to 0, is to show minimal or no income for the year, and spend money borrowed against their long term assets. Borrowing money isn't an income generating event, but it allows them to maintain a high standard of living while... | [
"\"Hello, I'd like to dispute a charge on my credit card.\" \"Okay, sir. What was the amount of the charge?\" \"Two million dollars.\" As others have said, electronic transactions are not acceptable for precisely this reason. Even cash might not be acceptable because it can to an extent be tracked, but the ease of ... |
Fresno, California is almost always at or near the top of "worst American cities" lists for some attribute. What are the factors in Fresno's history that led to the city's excellence in being so awful? | [
"As a followup question: I live in Modesto, which is nearly always at the bottom of these sorts of list as well, and I'm also curious as to what sort of factors caused these Central Valley cities, which have a surprisingly large population collectively, to consistently be placed on these lists."
] | [
"Karachi (largest city in Pakistan) is currently experiencing some large problems; both in crime, and politically. This is in part due to [Altaf Hussain](_URL_0_) who is the founder and leader of the [Muttahida Quami Movement](_URL_1_) - a political party in pakistan based in the city of Karachi. The problems surro... |
Is the apparent speed of the sun constant, or does it just seem to be moving faster at dawn/dusk because the horizon provides a reference? | [
"The Sun's motion across the sky is best described by a sine wave. It moves at a constant angular speed across the sky, but at sunrise and sunset that motion is almost entirely in the \"up down\" direction, while at \"high noon\" that motion is almost entirely in the \"east west\" direction. So, as it gets closer t... | [
"There's a chemical called melanin within skin cells that protects the skin from harmful sun rays. As these rays increase melanin moves to the surface to protect you more. As these rays decrease, the melanin is no longer needed, and so it moves back and so you 'lose' your tan. (I know this is a simple explanation b... |
Why aren't the vast majority of animals hermaphrodites? Wouldn't that be exponentially more useful, biologically? | [
"A couple things to note: 1. Evolution doesn't allow organisms to pick and choose what the \"best\" option is. Regardless of whether or not a \"more useful\" option exists, evolution just works with what it has. 2. Hermaphroditism comes with a substantial energy cost; it's not trivial for organisms to have the abil... | [
"They don't contradict each other, each model just works to different ends. Guessing that all are male is appropriate if you want to maximise the number of correct *individual* guesses. Assigning a 55/45 split is appropriate if you only care about the ratio of sexes in the group as a whole. For instance, suppose y... |
what stops lighters from exploding when you use them. | [
"For combustion, you need oxygen. There is no oxygen inside a lighter. When the butane inside a lighter is released, it reacts with oxygen in the air to make fire. Because there's a much higher pressure inside the lighter than outside it, oxygen can't get in while the trigger is flipped \"on\" since butane gas want... | [
"There is no 'correct' answer at this point because it's still a debated issue without an official and detailed response from Samsung. My best guess: they tested prototype models specially made from in-house production lines. These models would have a far smaller margain of error in production and their assembly pr... |
Does tectonic activity contribute to sea level changes? | [
"Tectonic activity can certainly affect sea level. It depends mostly on the speed at which the plates move, which in turn affects the age of the material on the plates. Consider that at a divergent plate boundary, material is being added to the plate. This fresh material is hotter and less dense. Because the plate ... | [
"The historians I've worked with relied on a lot of Geertz's work to explain the history of insular Southeast Asia, as well as other anthropologists. Perhaps one of the largest and first being Edmund Leach and his study *Political Systems of Highland Burma: A Study of Kachin Social Structure*, which helped explain ... |
Why do college professors curve test grades? Wouldn't that just encourage laziness and be an example of the failure of the instructor's efforts to ensure students learn? | [
"I had a professor say once, \"If you ace my test, I haven't tested you at all.\" The goal of the test is to determine what the student have learned. By making the test difficult, you are able to determine both the upper end and lower end of the abilities in your class. This is a good thing, as you are able to unde... | [
"For any given flight, typically 5-10% of the people with reservations won't actually fly. So instead of having empty seats and charging everyone more, the airline try to guess how many people won't show, and sell some extra tickets. When you buy one of those, you wan't get a seat assignment until you get to the ga... |
What would happen if we launched all our nukes at the moon? | [
"I initially imagined the moon exploding and the tides and everything being messed up and then the movie 2012. But then I decided I want a real answer as well. I'm here for that. Pretty good question, OP."
] | [
"Not enough energy to. It's like lighting a match in a snow storm and expecting it to melt everything. Sure, the match is hot, but theres a lot more cold than there is hot."
] |
Spanning Tree Protocol | [
"I'm going to go early 5 year old on this one. You have more than one way to get to something on the network. Spanning tree picks the best way, and blocks the other ways so things don't just go around in circles. Then when your best way breaks, it opens one of those other paths."
] | [
"TTP stands for Twitch Plays Pokemon. There is a stream on _URL_0_ where users can type b, a, left, right, etc to control a game of Pokemon. As you might imagine, thousands of people trying to do this yeilds interesting results."
] |
Why couldn't artists from the 16th to the 18th century create hyper-realistic paintings, as we can today? | [
"Check out Johannes Vermeer, he worked in the early part of the 17th century and is especially noted for making hyper-realistic, almost photo-realistic painting. (Keep in mind, when you look at his paintings that they are nearly 400 years old and show their age somewhat). I'd say it's safe to say that it was defini... | [
"Its not completely uncommon - for example I was associated with this study in 2006 _URL_1_ where using a new imaging methods we found the anatomy was not as described in most dissection studies. The upshot was that the way of doing the dissection masked the relationship between the tissues. New imaging methods all... |
Is it possible for an embryo to continue growing without developing into a fetus? | [
"Theoretically, the cells that form the inner cell mass of the blastocyst could progress through division without initiating the process of differentiation, however, that would result in the spontaneous abortion of the embryo. Basically, even if it did just continue to divide, the embryo would be deemed unviable by... | [
"> It doesn't kick upwards, it's just propelled. Its feet never extend It *does* kick upwards, and its feet *do* extend. It just happens very quickly, and is only fully visible in [a single frame of the video](_URL_1_). You can check out all of the individual frames [here](_URL_0_)."
] |
Why is it so terrible to release carbon from the ground if it came from the surface originally? | [
"It's probably not going to end the world, just make it less habitable."
] | [
"A simple example to augment the sciencey explanation: Basic idea: *Materials have a point of no return* A simple sheet of printer paper can flop back and forth for eternity with little adverse effect. As soon as something puts a crease in that piece of paper, it is pretty much permanently changed. That crease will... |
Why is spray deodorant cold when it comes out of the can? | [
"A few reasons, first you may remember from high school chemistry the ideal gas law. PV=nRT, where P=pressure, V=volume, n= number of moles, R is a constant and T is temperature. If you spray a pressurized gas (the propellant in the can), which is typically butane or propane, as the gas comes out of the spray nozz... | [
"Most microwaves heat food unevenly, so even though parts of the dish are heated to the point that they are too hot to eat, other areas are still relatively cool. Much of the 'rapid cooling' of microwaved food is just redistribution of heat from the hot areas to the cool areas, while heat lost to the environment is... |
Is it possible for a solid to be so thin that it can't be seen with the naked eye? | [
"Graphene is a one-atom thick material that is a solid, and it is invisible to the naked eye."
] | [
"The best way we have now to cool down a molecule is with “laser cooling”. We reached the lowest temperature ever, bringing a 3-atom molecule to withing a thousand of a kelvin of absolute zero. Molecules are a lot harder to cool down than individual atoms. The technique works by causing an electron bound to the ato... |
Sleep is good for humans, but why do especially newborns, babies and children then have a hard time falling asleep with lots of crying and obvious resistance? | [
"Children are constantly growing and learning new things. Those new things excite them and stimulate brain activity. So even though they need to sleep, their brains are hyped up with all this new info so they fight falling asleep. A lot of babies need help relaxing enough to go to sleep, and young children need a r... | [
"Please use the search function. _URL_11_ _URL_12_ _URL_13_ _URL_11_ _URL_12_ _URL_11_ _URL_12_ _URL_13_ _URL_12_ _URL_13_ _URL_13_ TL;DR: Why is a bad question with no good answer. We can't tell entirely with other animals, because we can't directly communicate though anecdotally, many seem to."
] |
If skin cells are one of the fastest replicating cells, how come moles, and birth marks don’t disappear over time? | [
"Moles are still skin cells. So imagine you have an area of skin, and some part of it is “mole” cells and some is regular cells. Both parts are sluffing (losing skin cells) at similar rates, and then replacing those cells at similar rates. So the shape and structure of moles might change overtime, but on average th... | [
"Building a car is easier than *rebuilding* a car that's been obliterated in a ghastly accident. You can follow the same steps to build the new car every time and it'll work every time. Rebuilding the totaled car is a lot trickier. Each case is unique. What's damaged? How badly? What can be saved? What needs to be ... |
What would you be experiencing inside an elevator descending at 50% terminal velocity? | [
"Keep in mind terminal velocity is a certain speed that doesn't change, meaning there is no acceleration. If there is no acceleration, the laws of physics remain exactly the same. It would feel the same as you sitting in your chair right now. Things only feel different when you start introducing acceleration!"
] | [
"Im getting tingly while laying in bed just thinking about standing on the edge of a tall building or cliff."
] |
Why do TV prices shoot up from $3-4K for an 80 Inch model to $120K for a 110 Inch Model? | [
"Flat screens come on sheets out of ,essentially, [a \"printer\".](_URL_0_) That printer is only 80 inches wide. Like paper, they can cut smaller sizes out of that sheet easily. To go bigger, they have to \"sew\" two sheets together, with is costly. Imagine taking two pieces of paper and gluing them together in... | [
"Your coworkers likely don't know how tax brackets work. That's unfortunately common. Here's a basic example of how they work and how your coworkers think they work. Let's say income between $0 and $50,000 is taxed at 20% and income over $50,000 is taxed at 30% - So if you earn $40,000 you will pay $8000 in incom... |
Why can't a phone connect to multiple speakers via bluetooth? | [
"It can--there are some new technologies out now that allow it, but only with certain hardware, and the new Bluetooth 5 spec appears to allow streaming to at least two devices at once. We're getting there!"
] | [
"For the Heinsenerg part: When you try to localize an object within a very small space, the energy of this object will be very big. That's actually something more fundamental than H.U.P., it's actually related to the fact that very localized functions have very broad fourier transforms. Essentially, you cannot have... |
Why are jeans bad at keeping legs warm during the winter? | [
"Real denim (not that garbage made with nylon or spandex) is actually one of the best fabrics for keeping out the wind, and keeping off the cold. Like /u/toadog said, old-fashioned 100% cotton Levi's keep you pretty warm, synthetics (like nylon) not so much. If you put on a pair of thermal underwear (classic long j... | [
"[They do freeze. They just don't normally freeze solid. In the more extreme climates, like North Dakota, engineers incorporate heating systems into the tank design...](_URL_0_)"
] |
why is red light better for your eyesight in the dark? | [
"On headlamps the red light is for hunting and night hiking. It uses less power and isn't as bright so your eyes adjust so you can see more of things in the periphere that aren't lit up. But, more importantly, I've heard many animals can't see red light (Edit: many nocturnal mammals especially lack L-cones), or at... | [
"Having the white bars provides depth perception. You can now tell with certainty if something is closer or further away, by whether or not it is in front of or behind the bars."
] |
Why does rainfall happen all at once instead of slowly and overtime? | [
"I take it you've never lived in the Pacific Northwest? Rainfall in that area starts in late September and ends for a short break in February. This isn't a sudden and heavy downpour, but a never-ending drizzle. Sometimes it's only a few drops per foot, or shows up as a mist instead of droplets heavy enough to conde... | [
"Kind of like if you're looking through some legos for a number of different parts, you usually come across one that you need so your search goes quickly until there's one last part you need. It might take you awhile to find that last specific part. That explanation is probably wrong but that's what I would say to... |
Almost everyone has different handwriting. Since we all learn the same letters, why does this occur? | [
"We are human, so we cannot print exactly the same letter every single time we write a letter. We make errors that then become habit. People also hold the pencil differently which can lead to different hand writing and pressure on the point."
] | [
"I'm not 100% sure, but I feel like it's because the person who sang it perfectly is really only interested in getting all the notes and stuff correct. Whereas the other, just wants to sing it whether it's perfect or not. It's sort of the same with jazz music. There's white jazz, and there's black jazz... White jaz... |
What exactly was Egypt's territorial height at the pinnacle of its power, during the New Kingdom? | [
"[Map: New Kingdom of Egypt c. 1550 BC–c. 1069 BC](_URL_0_) [New Kingdom of Egypt - Wikipedia](_URL_1_) -------------------------- Hopefully someone will make a correction if this is inaccurate in any way."
] | [
"While not a scientific answer to your question at all, I want to suggest the excellent movie [Before the Fall](_URL_5_) (German Titel: Napola – Elite für den Führer) to anyone interested in this topic, which is a story about pupils in an elite high school in the German Reich."
] |
Why does the door close so loud when I have a window open? | [
"When you close the door, a bunch of air is displaced, and it has to go somewhere. If you don't have a window open, the only place the air can go is to rush out the door gap as you're closing it. This is difficult to do, and so the air forms a higher pressure \"cushion\" which prevents the door from closing as hard... | [
"It has nothing to do with the file. It depends on whether or not the program says it's done with the file. Your word processor says \"hey I'm using this file\" for as long as it's open; apparently, your media player says it's done as soon as the song is loaded."
] |
Why are civilian drones just now cheap and widely available? Haven't we had this kind of technology for years? Or had we simply not invented them yet? | [
"The biggest hurdle to consumer grade drones (usually quad copters) was a battery powerful and light enough to give you a decent flight time."
] | [
"Building is often done in bulk, dozens of houses at a time, which means you get economies of scale, not just in the materials etc, but in the laying on of services. Building a row of houses needs a trench dug for the sewer connections, for example, but you can do the whole row at one time - likewise the foundation... |
What makes fats and oils taste good? | [
"Fats and oils are essential to a healthy life, and (in moderation) are required for proper growth of the human body. Because if that, we have evolved to prefer the taste of fats, when mixed in with other nutrients, like protein (meats), vitamins or minerals. Too much of it can be a bad thing, but the overreaction ... | [
"Neural adaption. Basically, your brain only cares about a *change* in stimuli rather than every stimulus that comes along. Your brain knows how to ignore a stimulus if it isn't changing. So, if you are tasting/feeling the same thing all the time, your brain is going to ignore it."
] |
Does a rainbow extend into the invisible part of the spectrum? | [
"It also extends into the infrared, which is how that type of light was discovered. A prism split sunlight, and then thermometers placed past the Red got hot. Edit: [More info on Herschel's experiment](_URL_0_) /u/fosighting [link to try it yourself](_URL_1_)"
] | [
"I recommend listening to Feynman describe the sum-over-histories model of quantum electrodynamics (for which he and two other men won the 1965 Nobel prize in physics): [Here's the video.](_URL_0_) There are a lot of amplitudes, phases, and little spinning clock analogies involved. Essentially, light takes all poss... |
Why do games cap frame rates? | [
"In most cases I'm aware of, it's simply because the game was developed for consoles and then just ported to PC without taking things like this into consideration. In some cases though, it might be necessary because things like ingame physics are tied to the framerate and they would not work as intended with an un... | [
"When you watch a video it only needs to send the video as fast as it needs to in order to play it back. When you download a large file from Steam it attempts to get you the file as quickly as possible."
] |
What exactly is predestination? Why do followers like Calvinists believe it? Why do they ideally try to be good people? | [
"It is the belief that God controls all thing to such a minute detail that there is no free will. Those that God decides will go to heaven will always go to heaven and everyone else will go to hell. It does not matter how bad you are as a chosen person, and it does not matter how good you are as an unchosen you can... | [
"If you know the full Hamiltonian for your system and the initial state, you in principle know how the system will evolve for all time. The time evolution is governed by the [time-dependent Schrodinger equation](_URL_0_). However you don't necessarily know what the results of measurements will be. For example, if y... |
Why can't I just eat gummy vitamins, protein supplements, iron supplements, etc. and survive? | [
"Apart from the supplements lacking many vital components that are found in actual food, the rate at which you absorb the vitamins and the rate at which the actual solids pass through your body do not allow for adequate intake of the nutrients. Eating just supplements and not any solid food will just give you very ... | [
"Those websites aren't interested in what happens when SHTF. They are interested in what might happen this week, namely that people might send them money. They are definitely in favor of people sending them money. If sending you gold, or MREs, will get you to send them money, then they are all over that. Since the ... |
Why can we walk for hours without our legs hurting but standing still for less than an hour starts to hurt | [
"We evolved to stand as a way to walk, and everything about it is adapted to that purpose. Our balance is better when walking than standing still, circulation better, everything about it revolves around movement. To stand still is inefficient, joints don't work as well because they're not being regulated by a rhyth... | [
"Two reasons, though my explanation may be incomplete: 1. In humans, the central retina is densely packed with cones, giving excellent sharp vision, but very small \"pixels,\" if you will. The outer retina is more dominated by rods, which react to light but not color, and the \"pixels\" are larger. Therefore activa... |
What is going on on someone's head when they pass out at the sight of blood? | [
"Vasovagal syncope, in certain people, seeing blood causes the brain to wrongly stimulate the vagus nerve, which would cause a sudden decrease in heart rate and a widening of blood vessels; this would reduce your blood pressure and the amount of blood going to the brain. The brain, in response to loss of bloodflow,... | [
"[Rogue](_URL_1_), but seriously there are several studies on this. [Here](_URL_2_) is a news article. [This](_URL_0_) is a scientific article that relates epinephrine to loss of pigment. Epinephrine is linked to flight-or-fight response system. Hypothetically stress, or a \"shocking experience\" indirectly would ... |
What through history has allowed India to achieve its enormous population? | [
"You might want to check the [FAQ](_URL_0_), as we have a section dedicated just to this question! Enjoy!"
] | [
"If you're really asking 'why', no one knows. Luck. Chance. Possibly something else entirely. It's a deeply philosophical question. If you're asking how, tools. Tools made the difference. Humans were lucky enough to learn to use tools, to develop fire. That was what pushed us into the dominant position."
] |
What's happening with the atoms on a mirror when I step in front of it? | [
"Nothing is happening to the mirror itself. A mirror just bounces photons (light) off of it. If you throw a tennis ball at a wall and it bounces off the wall, the wall hasn't changed at all because the ball bounced off of it."
] | [
"Think of it like a hose... and a room made of sponge. The light bulb is a hose, spraying water (light) everywhere. The room is a sponge, absorbing the water (light) all the time. The moment you turn the light off, it's like closing the faucet to which the hose is attached. It stops spraying water (light) everywhe... |
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