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nzg5dj | why does it hurt when u burp through your nose after carbonated drink? | Chemistry | explainlikeimfive | {
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"The bubbles from the drink are made from carbon dioxide, and when you burp the gas back out it dissolves into water in your nose and forms carbonic acid, which stings your nose. You might find if you take a deep sniff from a bottle of carbonated drink you get the same thing, and this is also what makes carbonated drinks taste different after they've gone flat."
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nzh0kw | What about a traumatic brain or spinal injury means people (those who are fortunate enough) have to “learn” to walk again? | I totally understand severing or damaging something physiologically means messages aren’t transmitted anymore, but how some of these people “learn” to walk again. Is it a new neural pathway? What are they learning? | Biology | explainlikeimfive | {
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"Edit: idk if you edited your post or it was just displaying strange, but it sounds like you already understand most of what I'm saying. I'll leave it anyway in case it helps. *** Damaged nerves. The spinal cord is super important in sending instructions from the brain to the rest of the body. It has a TON of nerves. When these nerves are damaged or severed, the brain can no longer send (or receive) all the info it needs. Part of the initial recovery is waiting for swelling to go down --- kind of like when you squeeze a hose with water and the water coming out slows down. Nerve damage in the spine is hard for the body to repair, so there may never be as much information from/to the brain. Symptoms that cause more pressure on the nerves can also become permanent. Spinal cord injuries also often involve a long period of rest and inability to move, meaning **the muscles used to walk weaken a LOT.** So a successful recovery is a combination of healing, figuring out how to walk with reduced information transition, and rebuilding the lost muscle. An analogy: ever had head phones with a damaged cord? The sound might still come through, but it can distorted, one-sided, or going in and out. It's usually very reactive to touch, where bumping it wrong worse until you line it up just right."
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nzh7oi | Why are lighter skinned people more susceptible to skin damage by the sun? Should their lighter skin reflect more sunlight? | Biology | explainlikeimfive | {
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"It reflects more visible sunlight - but skin damage is caused by invisible ultraviolet, not visible light. All skin is opaque to UV, but darker-skinned people have more of a chemical called melanin that absorbs UV instead of the other biological molecules located in the skin.",
"The damage is caused by invisible light in the ultraviolet range. The melanin in the skin is really good at absorbing UV which stops its harmful effects. The darkening in the visible range is only a side effect and serves no purpose.",
"so to answer your question i have to first explain about melanin Melanin is a chemical compound which gives a human being their colour ..........its produced so we can defend ourselves from the harmful uv rays of the sun Darker tonned people have a lot of Melanin so thereby more protection from the uv rays Lighter tonned people have very less melanin so thereby less protection from the uv rays",
"The lightness of the skin doesn't really protect all that much, as you don't reflect a lot, especially in the UV spectrum. People with darker skin have more [Melanin]( URL_0 ) which accumulates in special parts around the skin cells and has the special property of being able to block out UV light (which is actually what damages your cells). It does have downsides though: with darker skin you heat up more, and your body can synthesize less Vitamin D.",
"There's actually a fascinating correlation between darker skinned people living closer to the equator and lighter skinned people living further away from it. Dark skin resists sun damage better than light skin, so people with darker skin can better survive in the sunniest climates, but in cloudier regions to the north where there's less sunlight, people with darker skin can't synthesize as much vitamin D as lighter skin people can. Dark skin vs light skin serves a totally logical purpose and is a natural adaptation to climate. It's insane how humans get so heated about something that makes perfect sense."
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nzhdit | Is there actual science behind the ubiquitous laser miner of sci-fi? If so, By what principle would they work? | Technology | explainlikeimfive | {
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"Are you asking if it is feasible to melt trough rock using light energy? Currently, no. This technology is beyond us. However [Plasma torches]( URL_0 ) are a thing, and even Rednecks can teach you how to build them."
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nzi14k | How come a six mile asteroid was able to wipe out the dinosaurs? The earth is 7,900 miles in diameter, were the dinosaurs all in one small area? How did the earth change because of the impact? | Physics | explainlikeimfive | {
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"6 miles is the low-end estimate; it could have been several times larger. But even a 6-mile object going many miles per second releases more energy than 10 billion Hiroshima bombs (the standard unit of disaster energy). Now the earth, a huge planet floating through space, was barely scratched; we didn't even know about the hit until not many years ago. But an explosion that big makes throws a massive amount of dust into the atmosphere that takes years to clear up. Imagine years of not enough light for plants to grow and it being extremely cold as well, and that's world-wide.",
"Imagine that you have a bathtub full of ash and you shoot a bullet into it. The bullet is very small in comparison to the tub, but the high speed of its impact causes a lot of ash to be ejected into the air. It is a similar case with the dinosaurs. The asteroid's impact itself would have sent a shockwave to and heated up the immediate surroundings, but it was the ash and dust ejected by it into the atmosphere that ended up being the dinosaurs' endgame, due to the fact that it blocked the sunlight and raised surface temperatures to levels that the dinos couldn't live in.",
"Velocity and energy Same reason a relatively small caliber hollow point can mess you up. Only a portion would have been directly effected, the rest died due to nuclear winter when the dust cloud blocked out the sun. Plant eaters died, and meat eaters died with no plant eaters to eat. If the bullet didn’t kill you, the infection did a month or two later. If that makes sense",
"Here's the current top theory on how it happened. First, a big asteroid smacks into what would one day be coastal Mexico. Several things happen. A huge wave is kicked up and destroys many coastal areas. A shockwave heads out through the atmosphere also damaging nearby life. But most importantly, an enormous amount of rock is ejected from the crater into the atmosphere and through it. It's ejected waaay up, and a lot of it arcs up into space around earth and then starts to fall back to earth. As zillions of tiny bits of rock re-enter the earth's atmosphere, they heat up with friction while falling. This heats the atmosphere too, and there's so much debris the entire atmosphere is heated to oven like temperatures. Basically, the sky is now red hot and glowing like an oven set to broil for a few hours. This ignites lots of plant life in a global firestorm, and basically cooks any animal life that can't get underground or into the water (one notable pattern during this extinction event was that the only land animals which survived were either small or semi-aquatic...the kinds of animals that could have more easily hidden from the heat). Between the fires and the huge injection of steam and soot into the upper atmosphere (plus the possibility of megahurricanes if sea surface temps got warm enough), sunlight was likely blocked from much of the planet's surface for an extended period of time (possibly a few years), and between the low light and low temperatures plants probably had a hard time growing, meaning food would have been scarce, further wiping out any surviving large animals in the ocean as well as the land. It's also thought that the impact might have kicked up a lot of sulfate rich rocks which would have caused acid rain during this time period, screwing with pH in streams and oceans. Then, after the smoke finally cleared and the sun could shine to the surface of the earth again, there was probably a period of intense global warming. The impact his carbonate rich rocks, which would have released a ton of CO2 into the air, and killing off all the plants probably didn't help either. So the world would swing wildly from much colder than usual to much hotter, further killing off surviving life. By the time everything settled down again, global ecosystems had been wrecked and the only dinosaurs left were little flying guys...the ancestors of modern birds. Oh, and at what seems to be the exact same time that this impact happened, there was an enormous volcanic eruption going on at the exact opposite side of the world in the Deccan of India...not a single volcano, but a whole area of 1.5 million square kilometers being covered by floods of basalt...it would probably have looked like something out of mordor. This seems to have started before the impact, but the impact may have shaken things up enough to cause a much larger eruption. While consensus is that it wasn't the major cause of the extinction, it may have caused climate change right before the impact that made populations more vulnerable, and an eruption resulting from impact disturbances might have made things even worse. So there you have it, broiled, smoked, chilled, and heated....all in all the KT impact was one very bad day for earth."
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nzilp4 | Inflation. Why is money worth more or less over time? | Economics | explainlikeimfive | {
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"Modern money is fiat currency - this essentially means it only has value because people agree it has value (and to an extent because governments back up the value by doing things like making cash legal tender for all debts). As a result, the value of money is going to vary based on how much money is around (the money supply), which is also typically controlled by governments or the central banks of governments. The money supply tends to increase over time primarily because that is the policy that governments and central banks have. Essentially, a stable, small amount of inflation is considered good for the economy, because it encourages people to spend and/or invest money (no point in sitting on your money if it loses value with time). Inflation is often also used to try to boost the economy (making more money available means banks can give out more loans, more money can be borrowed/invested/spent, more happens in the economy) which can go wrong if taken too far.",
"Think about robinsons fruit punch. You add some water to the juice to make it not so sweet. If you keep adding water the sweetness starts to fade. In this case the water is actual physical money, notes and coins you see. The fruit juice is the value of the money, how much resources you have. If you increase the physical equivalent of your resource without increasing your resource then the equivalent begins to lose its value"
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nzj585 | How do babies/your body know when it's time to be born? | Biology | explainlikeimfive | {
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"No one knows for sure, which is why there's still a bunch of time at the end of a pregnancy where the mother has to be prepared for it to start at any time. There are a number of different theories and there are also physical signs that it's going to happen soon (the baby descends further down into the pelvis, for example) but as for what actually initiates it, we don't really know. Similarly when a mother is \"induced\" it is done by artificially giving the mother a bunch of hormones that the body itself creates naturally during the early stages of labour - but what initiates the creation of these naturally is also unknown."
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nzj6hk | Where does the sun's energy gets lost before reaching the outer planets if there is nothing to resist in between ? | If the space is empty and there is nothing to resist or absorb the heat from the sun then why outer planets like Neptune and Uranus are so cold | Physics | explainlikeimfive | {
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"The ~~cubed rule~~ inverses squared law. The suns energy is being spread across a larger area. Imagine your car beams in fog, they spread out and get weaker the farther away. Because they cover more area, the sun is the same way Edit: the reply to my comment is correct. It is the inverse squared law",
"What other people call here the 'Inverse square law' is just the 3d version of angular size. [Here is a picture]( URL_0 ) The sun radiates its light into all directions (360 degrees). If a planet is further away from the sun, it has a smaller angular size. This means more of the sun's light will 'miss' the planet. If you spread the same amount of light over a larger area (further away) the light is less 'bright'. The total solar power (sun per square meter) decreases the further you get from the sun and so it is colder.",
"[I think this diagram sums it up best]( URL_0 ) The energy coming from the sun gets more spread out the further you go. Imagine that the square labeled A is a planet, and the other squares aren't there. (The A square stays the same size but gets further away). As it gets further away it is hit by less and less energy."
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nzjddr | When computer processes (downloads, installations, etc.) reach 100% and stay there for a while, what actually goes on? | Technology | explainlikeimfive | {
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"Have you ever finished the job and then took a moment to put away your tools?",
"It depends on rhe application. In addition to what other people have said. It's entirely possible the programmer fucked up the display and \"100%\" is actually more like 70% Like if you tell someone you will be at their house at 6 but then show up at 6:20",
"[ URL_0 ]( URL_0 ) Tom scott breaks it down really well - basically, at best they are an estimate, and at worst, a terrible guess. As for pausing right at 100% for a bit, that can be intentional as it's a way of visually confirming \"hey, I'm done\". If the progress disappeared instantly the message might not be fully clear.",
"Often it's the antivirus checking the completed file, and some general cleanup/garbage collection.",
"Some separate process that is usually fast happens. For example, after the download it may have to rename the file from a temporary to the intended filename and do an antivirus check (the latter is what probably takes the most time).",
"They receive a very stern letter from the Board of Progress Bar Certification and risk a fine or revocation of their right to use progress bars until 100% means 100% for reals.",
"Software people have to program the installer how to display the progress. It can be things like 1-10% gather all the information you need, 11-60% copy the files, 61-80% verify everything went well, 81-100% clean up after yourself. What if something goes wrong at the end of cleaning up after yourself. Operating systems like windows can take ownership of files (through antivirus, etc.) which can prevent the installer from removing them. Ultimately, to a programmer, progress bars aren’t that important so they get less care than many other areas of the software.",
"Because the programmer doesn't know how the system will handle the program. What you see as \"running in parallel\" is, for the most part, your processors switching between iterating all these programs a chunk at a time. In modern PCs there could be true parallelism but usually you might still end up with the \"multitasking approach\" where you don't really run them all at once but practically do some stuff here, then move over there and then back to something else entirely. Also what is 1% of progress? Say you have 100 files in all different sizes and you want to move them to their specific place. Do you count 1 file = 1% or do you look at the file size or do you look at the system to figure out which jump is the fastest (likely not, but possible). So it's not straight forward what a chunck of progress even means and depending on what definition you pick you can end up with either a fast start and then some delay or a slow start and then finishing instantly. Also as other's have pointed out, the cleanup phase is also part of the progress which is something you cannot really plan all that nice. So it's actually not all that easy to make a good progressbar in advance as you don't really know the system upon which the software will be installed. Also let's be real the prime objective of a progressbar has been and always will be, to indicate that the process is still running and hasn't frozen or been corrupted yet. It's a visiual cue that something is working in the background and that some progress is being made."
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nzjyh3 | Why does the little stretch and shake that we do before or after sleeping feel good? What does it do the body? | Biology | explainlikeimfive | {
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"When you sleep, your muscles lose tone and fluid tends to pool along your back. Stretching helps to massage fluid gently back into the normal position. It also activates your parasympathetic nervous system and increases blood flow to your muscles. It's thought that stretching may also release endorphins that help to reduce pain and enhance your mood.",
"Muscles that are at rest tend to retract because they aren't being used, like ropes not being stretched once in a while. The \"stretch\" you do is you flexing your muscles and stretching them to prepare for movement after docile sleep patterns. Basically you are reawakening the docile fibers in you muscles that decided to go to sleep when not in use."
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nzjz5y | Billion year old water was recently discovered on earth. How old can water get? | Earth Science | explainlikeimfive | {
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"Not sure what you mean by billion year old water? How do you define the age of water? Pretty much all the atoms on earth are billions of years old. If you see them as particles, not waves, at least... Most water on earth arrived billions of years ago. But since then almost all of it have been inside or part of countless rocks, mud shoals, bacteria, virys, microbes, plants and animals. Does it still count as \"water\" or do you start counting age from zero every time it is exhaled by a mosquito or evaporate from a leaf stomats? Even water sealed under ice or in the abyssal sea is in constant flu between being water molecules or being split into a proton (H+) and a base (OH-) component, and mostly re-form water molecules with a different atom. Is that old water re-arranged or new water?"
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nzko98 | In marble experiments to show the effects of gravity the marbles always fall into the object. Will Earth eventually "fall into" the sun? | [ URL_0 ]( URL_0 ) This is a sample of the type of experiment I am talking about. They use a heavy object to push on uniform plane then roll marbles on it. To show the heavy objects pulls everything in using a specific pattern. The same pattern is made by large objects in the universe. Particularly the solar system. The question I have is that in all these experiments the marbles eventually collide with the large object. Is the same thing going to happen to earth eventually? Are we just a giant marble falling into an even bigger marble very very slowly (from our perspective)? | Physics | explainlikeimfive | {
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"Im on phone so this will be short. Every marble starts out with a velocity just like a planets velocity. The difference here though is that on earth friction reduces the marbles velocity which results in them colliding in the middle eventually. Meanwhile in space, there is a vacuum and zero friction. This allows the planets to not reduce their distance between themselves and the sun. Tldr: friction is ruining it :("
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nzkojy | what happens if we charge our phones overnight? Does the battery life really reduce? If yes what's the science/reason behind it or is it just a myth? | Technology | explainlikeimfive | {
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"Part truth, part misleading, part bullshit, part ancient bullshit. * Truth: Batteries lose capacity over time. No matter what you do, it'll eventually wear out. * Truth: Using a battery a lot kills it faster * Truth: Overcharging a battery is a very bad thing. * Truth: Completely emptying a battery is a very bad thing. * Bullshit: Leaving a phone charging overnight is overcharging it. No, lithium won't take that kind of abuse. No modern cell phone (by \"modern\" I mean anything that looks remotely like a smartphone -- so anything made in almost the last two decades) is that stupid, and they'd start lighting themselves on fire if they were. This applies to cheap lead acid/NiMH chargers for round batteries maybe. Cell phones have nothing to do with this. * Misleading/bullshit: Fully discharging and recharging a phone does something useful. Sorta, sometimes. It doesn't do anything good for the battery. What it can help with is resetting the phone's internal estimation of the battery capacity. If your phone randomly dies at 15% it might help it readjust its internal accounting and figure out where the new 0% is. But it doesn't do anything positive for battery health. * Misleading: Optimization strategies, such as charging only to 80%, when applied to cell phones. The reality of it is that pretty much none of them do. A modern cell phone is a 24/7 device. A strategy that applies to preserving the battery life on an electric drill doesn't apply to a cell phone because you can't really not use a phone. * Ancient bullshit: Memory effect. That was a thing on an old, very specific chemistry nobody uses anymore, certainly not on cell phones. It was also barely reproducible in laboratory conditions. TL;DR for cell phone usage: * Don't let it discharge fully. That's very bad. * Plug it in whenever convenient. It'll wear out eventually anyway. * Don't use fast charging unless you need it. It kills the battery faster. * If you want to maximize battery life, and your phone has a mode for it, then use that. If you don't, you can't do the \"stop charging at 80% thing\" by hand on a phone, so don't even try. You'll just kill the battery faster. * Don't buy a ridiculously expensive phone with a hard to replace battery unless you can afford it."
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nzku53 | What do Electrolytes actually do to your body to help replenish you? | I know I’ve heard they “help hydrate”. And google says they regulate nerve and muscle function “. But how? | Biology | explainlikeimfive | {
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"Electrolytes are a fancy name for ionic salts that split into positive and negative charged parts when dissolved in water. They are important to the body because they are actually what make up a lot of the \"chemical signals\" that make the body function. The balance of certain ions, like calcium, sodium, potassium, and magnesium, can trigger your cells to do many things, like uptake or release water (this helps regulate blood pressure) or fire nerve impulses (this helps muscles contract). Electrolytes alone aren't hydrating, in fact eating pure table salt (sodium + chloride ions) will do the opposite because it will pull water out of tissues to match the relative blood concentration and help you pee it out, but the beverage (juice, gatorade, powerade) that has electrolytes in it has plenty of water to make up for it. It's important to supplement your electrolytes, especially when you perform physical activity, because sweating excretes a large amount of them, that's why sweat tastes salty. People have also died from drinking too much pure water before (Hold Your Wee For a Wii), because the excess water dilutes the concentration of electrolytes in their body so much that vital nerve functions stop working correctly. So go crack open a cold Powerade (sugar free!) and feel content in helping maintain your body's internal balance."
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nzldrm | How do Co2 emissions keep growing year on year despite rapidly expanding renewable capacity? | Pretty much as it says in the title - I've seen so many headlines over the past few years about how economies around the world are transitioning to renewable sources for both environmental and economic reasons, and it looks good and promising. And yet, today, I see that Co2 emissions are set for their second biggest annual rise ever, which is quite distressing- how is this happening? Forgive me if this is a foolish question | Earth Science | explainlikeimfive | {
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"Because CO2 emissions aren't determined by how much renewable energy we produce. We could cover the world in solar panels and windmills and our CO2 emissions would remain the same if we still *also* burned all the oil and coal we could get hold of. We're producing more renewable energy than ever, sure, but we're also *using* more energy than ever, and we're still building new coal plants, and we're still buying more and more (non-EV) cars. In order to drive down CO2 emissions, we have to stop doing *those* things. Building more renewable capacity is at best a means to an end. It doesn't do anything for the climate *in itself.* It might enable us to make those kinds of changes, or it might just provide more energy allowing us to *use* more energy, without actually cutting down on non-renewable energy sources",
"The caveat to those headlines is that we are *trying* to transition to renewable sources. There's still a majority dependence on fossil fuels. Combine that with the fact that we've needed more energy than ever, well, you'll get more CO2 than ever. Not to be all doomer about it. I actually am quite optimistic that we can pull out from this, but it's definitely the global problem of the century.",
"Emerging countries are developing fast and don't have ressources and cash ( and the will) to go \"green\" yet. Why spend 10x more money on a solar plant when I can build 10 coal power plant for the same price. Every year you have millions of people coming out of \"poverty\" in said countries. They want to live more comfortably and they decide to buy a car (we are talking about millions of new cars going on roads each year), they get access to electricity (with the new dirty coal powerplant) so they buy a fridge, an oven, a washing machine, air conditioning, a lawnmower etc..(and that demand leads to more powerplants) They are also able to book holidays so they hop on planes to visit far away countries etc etc etc Only highly developt (rich) countries are transitioning into renewable energies and limiting their co2 output by going \"green\" but imo they are mostly relocating all the dirty things in poorer countries. ( Apple has their circular hq with solar panels but the amount of co2 required to build an iphone is ridiculous) If you top that with the emerging middle class in the rest of the world you end up with a global increase in co2 emissions despite rich countries going \"green\""
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nzmkon | Where does money originate from? I get paid from my company who gets paid from its customers who get paid from their customers... | Economics | explainlikeimfive | {
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"It depends on the country, but money is created by the government or central banks. After it is created it does what you just described, it circulates (passes from one person to the next). You can think of money as the blood of the economy. It needs to circulate to keep the economy alive. GDP is essentially a measure of how much money is circulating. When money was principally bills and coins, they would get worn out and replaced by the government or central banks. Now that money is principally digital, it can circulate indefinitely.",
"From the government - they print money and distribute it to various places, particularly banks. Trade is quite useful. It lets people specialise in one thing and then trade the thing they make for other things they need, instead of everyone having to be good at making everything they need. This is the foundation of civilisation. However, trade has a problem: If you don't have anything I want, you have no way of getting this chair you need from me. This is a problem you may have experienced in various online games, like Pokemon. So, often what happens in trade economies is you start trading for something you don't personally need, but are reasonably confident you can trade to someone else in future for something you *do* need. Typically, this is something with a universal purpose that everyone needs, like grain, flour or rice. Because everyone needs it, it's something that you're pretty likely to be able to trade to someone else. Money is just the evolution of flour. Where flour still has some use besides being traded, money exists *solely* to be traded. The first currencies were directly made from gold, silver and copper, and other rare materials that had no purpose besides being currency. When society gets stable enough, these rare, useless materials gain abstract value solely as a token of trade. If everyone agrees that a silver coin is worth 2 sacks of flour, then a silver coin has value, and you can give me a silver coin for this chair because I know I can trade that silver coin for 2 sacks of flour, or something of equivalent value, should I need to do so. You may be wondering why I've taken you on a short trip through the history of trade. That's because this explains where money originates: Mines. The first system of currency (flour) literally grew on trees, and as society got more complicated, the second system of currency (precious metals formed into coins) was dug up from the earth. This sort of direct metal currency has a problem though, in that as the supply of resources rises, the value of coins need to decrease to account for it, but because there's a limited supply of gold and silver, it can't decrease. What societies inevitably have to do then is abstract their currency again. At this point, gold and silver are swapped for less valuable materials marked with an exchange value. You can go to the government and sell them your gold and silver for a predetermined quantity of money made from cheaper metals like copper, and iron. You can also do this in reverse: You can take your money to the government and exchange it for a pre-determined quantity of gold or silver. This is called having a silver or gold standard, and it's the way money operated until very recently. The value of your currency is still tied to the value of gold and silver, but it is not directly that gold or silver: The value of say 1 gram of iron as a material is less than the value of 1 gram of iron that's been shaped into this marked coin, because the government has promised that you can exchange that coin-shaped gram of iron for a specific amount of gold or silver that's worth more than 1 gram of iron. Now, the government is making money by telling you that cheap metals in particular shapes is worth more. Nowadays, the gold/silver standard has been swapped for something called floating currency. This is where the value of currency is set against the value of other currencies on the global currency market. You can no longer exchange your currency for a set amount of gold, but you *can* exchange it for a set amount of another currency. This is what gives money value: the knowledge that you can always swap it for another currency that has value. The government still makes money by telling you this piece of paper in a particular shape is worth more than the basic materials, but the value of the money is no longer tied to the value of any specific object. The government can print as much or as little as it likes. If it prints too much though, the value of the money decreases long-term, because people have more of it to spend and so sellers can push their prices higher. This is what prevents the government just giving themselves infinite money: If they try, the money becomes completely worthless."
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nzmru6 | When people have medical procedures that end with devices drilled into their body (like halos and insulin pumps) how is that not agonizing 24/7? | How does having screws and other foreign objects drilled into your body that are both inside you and outside you at the same time not constantly hurt you as much as you'd think they would? Many people operate normally with things like insulin pumps inside them and I don't understand how they're not in agonizing pain all day every day. | Biology | explainlikeimfive | {
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"Your body has an incredible ability to get used to things with constant contact and pressure. It is why you can have a cut or wound that only really hurts when you're cleaning it, can sometimes find objects sticking to or in your skin without noticing, and (most relevantly) exist with implanted objects in your body. Eventually, assuming the implant isn't rejected, the inflammation and feeling of the object being in any way unusual subsides for the most part, with only fleeting or minor reminders.",
"Insulin pumps are not implantable. Most are still connected by a thin tube so it becomes something like a third arm or tail that just gets in the way instead of doings something cool.",
"I’ve read about the people who had the implanted insulin pump during clinical trials, and they didn’t have a lot of problems with pain or discomfort. Those pumps do not have an “outside” part, that’s the point of them. Just so you know, insulin pumps are not, for the most part, implanted. Insulin is delivered through a small cannula or tiny needle into your subcutaneous fat. You don’t even feel it."
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nzmx8a | Do we control brain or brain control us? | Biology | explainlikeimfive | {
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"Depends on how you want to define 'We' (or in this case, you) The thinking you do, and the 'you' that you consider yourself, ís your brain. So I would say, you are your brain, and you control yourself.",
"I feel like in a way it's a moot question because we ARE brain. It's like asking \"do you control yourself or does yourself control you?\""
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nzmxq8 | How is a leech or tick able to get lots of blood from anywhere, but a nurse with a needle has to hit a vein? | Biology | explainlikeimfive | {
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"The nurse with the needle is trying to get a lot of blood. Poke your finger with a small needle and a drop of blood will come out. A drop is quite a lot for a small animal. (also, the saliva of these animals has anti-clotting agents preventing the wound from closing, keeping the blood flowing)",
"The leech saliva has a numbing chemical. It secretes its saliva and bites using razor sharp teeth (leaving a wound which is shaped like the mercedes star). This bite is on the skin surface only and the blood that oozes out of it is sucked by the leech. So over a period of few minutes it may suck out few tens of cc's of blood. And that blood is from a wound which is about 3 mm x 3 mm size. The nurse actually uses a needle to draw blood out of a much much much smaller (needle) wound. So to draw blood out in a reasonably small time she needs to find a deeper vein."
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nzn0fp | When a YouTube video starts buffering, why does the picture freeze first but the sound continue for a brief moment? | Technology | explainlikeimfive | {
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"Sound takes a lot fewer bits than video. The video runs out of bits, and puts up the buffering symbol so you know. The sound just stops when it runs out of bits, but the bits on hand last longer than the bits on hand for video. Not a lot longer, the buffers take the smallness of audio into account, but they are not managed down to the bit, the \"chunks\" of audio are about a second long."
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nzn75a | Why do our brains give us nightmares? | Biology | explainlikeimfive | {
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"It's probably not \"giving\" it to you. Your brain is thinking. Sometimes it thinks about the past or the future. And sometimes those things make you anxious or scared. Sometimes your brain is just feeling anxious in general and that anxiety cues other memories of anxiety inducing things because it feels similar. And in the process of making a dream, all that junk just kinda topples out and you have a nightmare.",
"The honest answer is we have no idea. Despite being studied a lot there is no scientific theory that explains why we dream at all. Plenty of data and correlations, but we still just don't know.",
"I have chronic pain and was told in my sleep my brain will make up reasons for why I hurt. So when my back hurts my brain will tell me a big ass monster is trying to eat me."
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nzneh0 | why can there be such a big difference in temperature when the conditions and locations are the same. | Eli5: if I'm in the same area one day apart it can be 25c+ and then a good bit lower the next day. All conditions appear the same, no cloud, wind etc | Earth Science | explainlikeimfive | {
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"The atmosphere is constantly moving, and not always the same way from day-to-day or even minute -to-minute. For example, even though you are in the same place, the air around you yesterday might have come from closer to the equator and been warm and humid, but today is air that was most recently from the arctic and much colder. To add: we can predict which way the air will move with any accuracy only a few days into the future. After that, all the little changes that are random or unknown (called \"perturbations\") add up and our predictions are useless (called \"chaos\"). Even for weather the next day or a few days out, we can only look at the conditions (temperature, humidity, pressure, winds) and say what usually what happens when the conditions are like that. That's why the weather person is *always* wrong."
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nzp14u | How do the muscles of the eye close the eyelid? | Muscles can only contract (pull, not push) and there is no space across the eyeball for a muscle to span, a ring of muscle (sphincter?) around the edge (orbit?) of the eye could close it like a drawstring but that is not the case as the corners of the eyelid don't move, two muscles anchored at the corners of the eye could close a slit but the eyelid has to follow the contour of the eyeball so contraction at the top and bottom wouldn't have a closing effect only a compressive effect on the eyeball, it can't be that the eyelid is just relaxing as both eyelids work to an extent upside-down. I'm stumped but I'm sure there is a simple explanation. | Biology | explainlikeimfive | {
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"> it can't be that the eyelid is just relaxing as both eyelids work to an extent upside-down \"Relaxing\" doesn't mean that it just lets gravity take over; it means that it goes to it's untensed state. So if the untensed state for the eyelid is closed, it will return to that state (as best it can) whenever the muscle relaxes. For another example of this, place your hand, palm up, on a table. If you completely relax your hand, your fingers won't lay flat; they'll be curled slightly upwards off the table. If you force your fingers to lay flat, you'll notice that you are exerting yourself a bit; the natural state of the fingers is to slightly curl, so even to \"allow\" gravity to pull your fingers requires your muscles to exert some force."
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nzpm99 | -How does hanging from a pull up bar help your spine? Should everyone do it? | Biology | explainlikeimfive | {
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"In the best case scenario, it puts your spine in traction so the disks aren’t compressed and the nerves get more blood flow. That would be more effective if you hung upside-down. However, it takes a lot of core and upper body strength to get in and out of that position, not to mention landing. I don’t recommend it: • without a spotter (if you’re upside down) • if you have shoulder issues (hanging) • if you have knee and ankle issues (landing) • if you have wrist and finger issues (holding on or regrasping the bar) • if you have bridged or fused vertebra, especially in your cervical spine (may actually be painful) • if you have issues with your trapezius or sternocleidomastoid muscles (may worsen your pain) • if you have a weak core (safety) So as you can see, once you’re about 25, there are lots of precautions you need to take"
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nzq1e8 | Why do we get aroused when watching other members of our species mate? | Biology | explainlikeimfive | {
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"Part of natural selection results in beings generally wishing to reproduce. In many instances, the male reproductive goal is to get yours before the others do so that it's your sperm that makes it in there. In fact, the penises of humans and other primates are flared out at the head so that they can actually pull semen out of a vagina--if someone has been there before you, you can get in and pull some of their semen back, giving yours an advantage as it is deposited further down. Thus: you see people getting it on and your mammalian brain wants to get in there too. It's all very much a primitive response."
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nzqmh1 | How and why are “decreasing birth rates” a problem? | Economics | explainlikeimfive | {
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"Most first world economies are predicated on a model of perpetual population growth, which is of course unsustainable.",
"It seen as a negative because most nations have built tax, wealfare and healthcare with the then assumed idea that the population would continue to expand. Healthcare costs, social security and other programs are less solevant financially with these programs. Another aspect that is troubling is that with a steady population size you less upward mobility. Take a look at Japan. Many mid and upper level positions are being held by long time employees that have been in those positions for decades. Without an increasing population the companies have no need to create new jobs this forces some stagnation in the work force.",
"Economics. You want a robust workforce to drive the economy, especially when the older populations will put more and more strain on social systems that are funded by said economy.",
"Think of it less as a population issue as a whole and more an issue with a national ecosystem. The anxiety is that there won’t be enough young workers to keep a country going and economically viable as its population ages.",
"It's the rate at which it's decreasing which is a problem, alongside lengthening life expectancies. More people are going to be living into their 90s and in need of full time care, with either no children or just 1 child to provide that care. Take into account the people who are not willing or able to care for their elderly parents and you end up with a huge burden on the state to provide care for the masses. Can you even find enough care workers to look after your elderly population, letalone pay them? It's a huge problem waiting to happen.",
"All this talk about the economy is really just about social security taxes. Those taxes workers pay go directly to pensions of living individuals, less workers means less money to pay out. Essentially breaking the system.",
"1. The global economic model is based on growth. CEOs get paid based on how much they grow a company, not how high quality their products are. The capitalist system needs ever more bodies to work to increase growth or the whole system collapses. Capitalism is a zero sum game, so if your country or region has fewer people, those economic gains you COULD have made are going to someone else, maybe a competitor. 2. If population evens out, you have fewer people paying into pensions and social services, while people live longer and need ever increasing amounts of medical care in their senior years. The fear is that there will be a \"bubble\" in a few decades where there will be more seniors than working people and the whole system will collapse. This doesn't mean that decreasing birth rates are actually bad, just that the systems we've implemented in our societies depend on that growth. These systems might need to be changed and people don't like change. The real truth is that a stable population is better for economic security, education, global pollution levels, and climate change.",
"Generally speaking an influx of labor is good for the economy, this goes for birth rates and for immigration. The long term problem with lower birth rates is that eventually you'll have a huge older population that can no longer work and a smaller population of younger workers trying to provide for them. In other words, the taxes paid by 50 young people won't be enough to cover the social security for 100 old people. As long as birth rates are increasing, you'll have 150 young people paying taxes to provide for 100 old people.",
"In general it is a good thing however it creates some temporary issues with the age profile of the population, specifically a large number of retired persons and a smaller number of working people generating money and tax income to pay for services the elderly may require.",
"I think it has to do with workforce numbers and things like that. Using the workforce example, in U.S. the current senior population, we'll call generation 1, usually came from larger family groups (6 kids per family is considered high in the present day U.S. but is typical I orevious years). So as all these folks are retiring or dying out, the next generation 2 steps up... which is a smaller population that came from 3 - 4 per family. My generation 3 will then step up to fill that second generation's job openings and most of us came from one or two kid households. So my generation is mostly not having kids for generation 4 .. There are now empty jobs which hurts the economy. So our population is probably 1/6 th of the numbers from our grandparents generation .... TLDR: less able bodied people in the workforce, which hurts the economy and stability of society",
"Part of the \"American dream\" is to get a well paying job, and then pour your income into something that will appreciate over time like a home. Once your kids are grown you can sell the home for more than you've put into it and move into a smaller house while living off of part of that increased home value. This only works if there is a steady increase in population. If there are less people around than when you bought your home, then there is less demand for houses by the time you sell it. You'll end up selling it for less than you put into it once inflation is adjusted for, leaving you less money to retire on. The same concept applies to most people's retirement funds as well. Money placed into the stock market depends on steadily growing demand to increase in value. Less people means less demand, means most money placed into stocks for people's retirement funds will shrink rather than grow. Japan is currently facing the problem of declining birth rates, and seeks to offset it by encouraging immigration."
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nzqphd | Why does the pain from banging your nose against something feel so distinctively different than other limbs/body parts? | Biology | explainlikeimfive | {
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"Probably because the nose cartilage gets hit and gets squished between the vomer bone right behind the cartilage. Also the nose have many nerves and the olfactory bulb....so maybe the feel of that it different from a limb.",
"Our nose is part of our sinus system. It's a series of cavities and canals that connect our nose, throat and eyes and ears. At breathing, seeing and hearing are pretty much the most important stuff we do, we have evolved to really protect these parts of our body. When you hit the nose you most likely do some damage to the sinus, It really depends on how bad. But that is most likely what you are feeling. In a way it's almost a similar feeling to being hit in the eye."
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nzrbf6 | Why inbreeding causes offsprings to be inferior? | Biology | explainlikeimfive | {
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"Statistics. Two related parents are more likely to share the same copy of genes that lead to undesired traits. Their offspring, then, would also be more likely to receive one or both copies. It can be more nuanced than that, with how genes are actually expressed for a given disorder, but it's largely consistent. These statistics add up over subsequent generations of inbreeding, but aren't inherent to inbred couples - any parents that are carriers to genetic disorders are more likely to pass them on when both are carriers. Genetic screening is a valuable tool in informed parenthood.",
"Concentration of bad mutations. Quite a few bad genes are only a problem if you have two copies of them. This is called a recessive trait. When inbreeding occurs there is a higher likelyhood that these bad genes will stack up since both parents will have the same bad genes.",
"We all have mutations in our DNA. Some of these only have an affect if both parents carry a particular gene. Inbreeding takes you to the shallow end of the gene pool, and vastly increased the probability of both parents carrying a problematic gene.",
"A lot of genetic mutations are expressed as recessive genes. So you need two copies of a gene in order to get the disease or defect. You’re more likely to get two copies of a recessive gene if the parents are related, since they’re more likely to be genetically similar.",
"Our genes come in pairs. Often there is a dominant and receive gene. So if you let' say have a dominant gene to not have a disease, and a receive gene to have the recessive, you won't show any symptoms. Our genes are full of thousands of these kinds of pairs. When we mate we both randomly pick one from the mother from their pair, and one of the father from their pair. If you ever have the bad luck to pull the receive gene from both the healthy father and mother, bang you have the genetic disease. Now different people who are diverse from each other carry different deceases from their genetic pairs. So let's say you are Bad/Good for disease A and Good/Good for B. And your mate is Good/Good for A, and Bad/Good for B, you have 0 chance of your offspring showing either disease's symptoms. But if you mate with someone close genetically to you, you now have Good/Bad and Good/Bad. So now there is a 1/4 chance of someone getting Bab/Bad and showing symptoms. Play these odds over hundreds of genetic defects, and you become very likely to create sick offspring."
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nzs5gd | How do animals of different species communicate? Is there a universal language or are there any non verbal cues? | Other | explainlikeimfive | {
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"The same way animals communicate to you. The way they move, the way they sound, the way they look at you. There is not a lot to be communicated in the wild, besides \"Let me eat you\", \"Fuck off\", and \"DANGER\". You understand animals as well as they understand each other.",
"Well you are an animal, think of how do you communicate to animals of different species, and the other way around.",
"They don’t. There’s no need for animals of different species to communicate - they are either prey or predator, competitor or can be ignored. Very very few cross-species commensal activities have been observed (badgers/coyotes, honeyguides and humans, monkeys/deer) and they don’t communicate as much as one interprets the behavior of the other."
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nzsptw | why do cuts hurt? You hear of people not knowing they're cut until they see it, then it starts to hurt. What makes a cut hurt? | and follow up, why do small cuts like a paper cut, sometimes hurt more than larger cuts? | Biology | explainlikeimfive | {
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"Sheets of paper are not as smooth as they look. Under a microscope, you can see that the edges are rough. When they cut you, they don’t cut cleanly - they more tear the skin than slice it. Whereas an extremely sharp scalpel, for example, is smoother, and gives a cleaner cut.",
"I don't know about the first question, I'm not a medical doctor or something, but I bet it depends on pain receptors and where the cut happens. About paper cuts, I think it's just a matter of perception: paper cuts tend to happen on finger tips (because that's where we usually handle paper sheets), and finger tips are very rich in nervous system terminations and receptors (for obvious reasons). Any cut on finger tips is painful.",
"Adrenaline can dull pain immensely. I had a platoon sergeant in the Army who was in some of the bloodiest parts of the Global War on Terror. He told us a story once of one of his guys running towards the enemy while seeking cover, having his entire foot missing. He didn't feel it, or even notice it was missing until it was pointed out to him. He was just running on adrenaline, training, and instinct.",
"The purpose of pain is simply to remind you that a part of you is injured so be careful not to do further damage. If you bang against something or whatever you may have felt it initially, but dismissed it as being no real damage. Then when you see blood you realize oh there is something wrong, I'd better be careful.",
"I believe there is a component to pain where some things hurt more because we expect them to hurt. If we don’t see a minor cut, we may not pay too much attention to the signals that our nerves are sending to our brain so it doesn’t hurt very much. But once we see the cut, we may expect it to hurt and then pay more attention to those signals and therefore it hurts more."
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nztm2a | How do QR codes work? | How are QR codes able to direct me to a website/ fill out correct information on blank fields? | Technology | explainlikeimfive | {
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"QR codes are a really cool way of encoding information in an image. You'll notice of to look at one, there are a few obvious landmarks that all QR codes share, the large nested squares in 3 corners, and the smaller nested squares in the final corner. These landmarks allow the decoder to determine the scale and orientation of the QR code. Once that's determined, the remainder of the QR code is a lot like binary, it's a grid of squares which are either filled or unfilled, like binary 1s and 0s (this is a simplification of the actual encoding mechanism which is quite complex and allows for a bunch of redundancy, which is why you often have a company logo over the QR Code, obscuring some of the grid, but it still works) The decoder then reads the \"binary\" message from the grid, and it comes out as a URL to a website or an app, or some instructions that the reader so can act upon.",
"You'll notice that there are some big concentric squares in usually 3 out of the 4 corners? with maybe a smaller concentric square in the 4th corner? These are the alignment anchors - the scanner detects these 3 relatively easily, and now can determine the extents of the code and its orientation. The relative thickness of the outer black and inner white rings in those gives the scanner some concept of scale. So it knows how big a bit is from the scanner's viewpoint. Also it knows there's a white space - equal to 1 bit's thickness - around each of those anchors, so no data is there. Then the \"bits\" get scanned starting from some known starting location in the code, and keep reading until the scanner reaches the end of the QR code boundary. The bits read are then turned into bytes and then into characters. All a QR code contains, datawise, is literally a string of characters. In the case of a QR code to open a website, its the URL: \" URL_0 \". All the Photo/camera app or whatever is \"reading\" the QR code has to do is throw the URL to whatever default handler your operating system has assigned to handle URLs starting with HTTP://.... if it was just text it would probably open a blank browser tab or a text reader. If it was a Spotify URL, it might open Spotify - what opens to read/take action on what information is in the code is largely up to the device operating system that is reading the code.",
"QR codes are read in a predetermined way (just like English speakers know to read books left to right). The black and white squares correspond to 0s and 1s which computers understand. The computer/phone translates those 0s and 1s into ASCII characters that humans can understand. Therefore a QR code is nothing more than a string of text translated into computer and printed out. Any string of text can be a QR code. You can use your name or a sentence or anything you want (assuming it's smaller than some specified length) The real magic comes when this string of text looks like a website URL. If, after the translation, the QR code looks like URL_0 , most phones will go ahead and open than in a browser for you. Now any website can be printed as a QR code. And the last bit of magic comes from the fact that you can use URLs to prepopulate information on certain webforms. But all that looks like a regular URL, which is just text, which can therefore be used as a QR code"
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nzufv9 | Why are smartphones incapable of setting two timers to run concurrently? | Technology | explainlikeimfive | {
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"> for some reason the iPhone just can't seem to handle that colossal computing task. The technology exists my friend, and the iPhone... from a required computing power standpoint - is more than capable of it. But Apple has decided that _normal_ users clearly wouldn't need such a feature. Therefore you don't get it. By default I should add. There's tons of timer apps in the app store that do this. It all comes back to Apple's iOS design aesthetic - you can only do one thing at a time; by default few apps are allowed to even run in the background. To switch you have to go \"home\"... you don't even have a button choice. You have one button. DO as we say and do it how we say you should do it! Typical Apple. ** In any android's clock/timer app, its right there: \"Add Timer\" and you can have a bunch all going at once. So... TL;DR - why? _Because Apple hates you_ and only pretends to like you because of your money. ** while Im not an iOS developer (so what do I know), my honest software developer suspicion is that iOS is just a garbage operating system - they could totally do this... and have lots of background stuff going on, but I iOS is just not designed to do multitasking very well. So adding lots of background tasks would expose this and shatter the utopian user facade that Apple so polished. If iPhones (or their apps) crashed as much as some androids or Windows ones can, no one would pay $1000 for an iPhone.",
"There sure can be, they just don't care enough to implement it. That's it, nothing more than that. Sorry for disappointing you. [Try third party applications from people who give a damn about that specific issue?]( URL_0 )"
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nzus1c | why does wood rot, what is the treatment that keeps some wood from rotting vs fossilizing? | Biology | explainlikeimfive | {
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"Bacteria and other microbes eat the wood, digesting the cellulose fibers. Basically to preserve wood, you need to break their digestive process - either be sealing them out, making the wood toxic to them or preventing access to the components needed (water and oxygen) to consume the wood. Wood under water lasts a long time due to the reduced availability of oxygen. Sealants keep out moisture. Pressure treatments infuse the wood with substances that kill the bacteria."
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nzusq5 | Why can't we watch over the airways broadcasts through the internet? | It is 2021, how come we can't just watch network tv (CBS, NBC, ABC, and Fox) over the internet instead of having to hook up a digital antenna and having the hassle of moving it around to ensure a strong signal? Yes, I am aware that broadcast tv can be viewed over paid streaming services like Sling, Hulu Live, and YouTubeTV. There are also stand-alone paid services like Locast. But why can't watching a network broadcast be as simple as connecting directly from your internet where your IP matches to the local tv market? | Technology | explainlikeimfive | {
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"When you have a satellite or cable TV hookup, the signal that the provider is sending out is \"Multicast\". That means they only need to broadcast one signal, and everyone can listen to it. With the Internet, multicast is generally a bad thing. The main difference is that anyone can be the source of a signal on the Internet. If we let anyone multicast their broadcast, it would be very easy to overwhelm all the connections and grind the Internet to a halt. So, multicast isn't generally used. That said, some ISPs do offer IPTV, and that *is* a multicast signal (for the broadcast stuff at least, not for on-demand). However, the ISP is the one controlling the signal. Even if you get, for instance, NBC through that IPTV service, it's still the ISP rebroadcasting the stream from NBC over multicast, so they control everything about it.",
"That's a great idea, and back in 2012 a company called Aereo tried it. Basically they developed a circuit board that had several individual tv antennas on it. Then they would set up their equipment in an office in a major city that had broadcast stations. As long as you were in what was considered the local market for those stations you could sign up to receive those stations. You would pay rent for a specific antenna and live TV would be streamed to you. You weren't paying for tv like cable, you were simply renting an antenna. I was an early alpha tester for the Houston, TX area. I live about 50 miles from Houston. The service worked great. Unfortunately the major broadcast companies didn't like the idea and they took it all the way to the Supreme Court and they ruled against Aereo. I believe they made a mistake, it would be no different than if I rented space on a tower in Houston and ran a 50 mile cable back to the tv in my house. URL_0"
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nzvq16 | why are lasers typically red? | Physics | explainlikeimfive | {
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"The diodes and components required to generate red laser light are cheaper and simpler than those required to make other colors. That's pretty much all there is to it.",
"Another non-trivial note: they are safer. Red light laser pointers are low enough luminosity, and low enough energy per photon that a standard blink reflex and turning away *should* prevent serious permanent eye damage. Which is important for something you hand to a random person two flail around entertaining cats. Even if they never point then at a person's face, it's quite easy to bounce it off the random reflective surface. Other colors are far more dangerous to eye sight. To the point that they really shouldn't sell green and blue \"over the counter\"",
"In order to make a laser you have to energize particles and excite them to emit the type of color you want. Red lasers require a lot less energy to make, so you can use cheaper batteries and put them in smaller devices and make them more affordable in general.",
"because they are very cheap to make, and also red color diodes are easily accessible. different colour has different properties. red colour has a wave length of around 600 nM",
"They're red because that is what is cheapest to make, the materials are widely used and abundant. The actual laser bit in a laser pen is usually very small, maybe width of a hair. They use the technology that makes computer chips to make the diodes. Interestingly the first ever laser was a red laser but made with a different material, ruby (not so cheap)."
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nzwaqq | What is the point/difference of using coffee creamer instead of milk? | I get especially confused when sometimes BOTH creamer and milk are used. I've worked at starbucks and to my memory, all our drinks are made with milk (unless otherwise requested) but never ever creamer. edit: is coffee creamer also similar to heavy cream and half and half? or totally different? | Other | explainlikeimfive | {
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"Half & Half - mix of cream and whole milk - makes the perfect mix of bitter black and creamy white. Cream - coffee flavor gets lost behind the overwhelming creaminess. Putting in less isn’t the same as half/half. Whole milk - does a good job on milder coffees. Not quite as full-bodied as half/half. 2%, 1%, and non-fat - Blah. Really good for cooling your coffee and watering it down. Also good for low/no-fat eaters. Non-Dairy Coffee Creamer - taste closely matches half/half but not quite there. Only solution for the dairy-intolerant who want that cream flavor. Almond-Milk, soy-milk, rice-milk —- Why, Coffus, god of coffee, hast thou forsaken me?",
"Coffee creamer is shelf-stable and light...much easier to store, much more portable. Milk needs a fridge. I have absolutely no idea why you'd use \\*both\\* in one drink, unless you just really like that particular flavour profile.",
"Creamer has more delicious fat molecules than ordinary milk. It's also more expensive and has a shorter shelf life. Those two non-taste reasons probably make milk the default at $B."
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nzwm8w | How do plant roots uptake nutrients? | ELI5: How do plant roots uptake nutrients? Im a amatuer gardener and I'm trying to better understand how plants uptake nutrients. I'm sure there is more to it than the root touches a nutrient and absorbs it. There must be a chemical process to it. I guess I'm looking for a simplified chemically based description of how roots uptake nutrients. | Biology | explainlikeimfive | {
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"You’re right that they absorb it, for the most part. Some nutrients are dissolved in water and absorbed along with that. Some plants (mostly trees) can also get nutrients from fungi (and sometimes other plants) by exchanging them through adjacent roots. Some plants will “trade” for nutrients they need by giving away sugar or other nutrients. This is called ectomycorrhiza.",
"You sort of answered your own question. Roots mainly take in nutrients through diffusion. This means that there is a higher concentration of nutrients outside of the cell than inside. When this is the case, the nutrients will move to the area of lower concentration (into the cell). The plant then sends the nutrients to other parts of the plant. This lowers the concentration again and allows diffusion to occur again. So the plant’s major role is to send nutrients away to allow the process to continue. Diffusion is an amazing process that sustains life.",
"Nutrient uptake in the soil is achieved by cation exchange, wherein root hairs pump hydrogen ions (H+) into the soil through proton pumps. These hydrogen ions displace cations attached to negatively charged soil particles so that the cations are available for uptake by the root. Some five year olds might get it. A proton pump is an integral membrane protein pump that builds up a proton gradient across a biological membrane. An example is employed in the ATP process. The root hairs cause the soil nutrients to become electrically charged which then allows them to pass the membrane in reverse, entering the plant. Or something like that."
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nzxfi1 | Why are keys of a computer keyboard arranged in that specific way? | Technology | explainlikeimfive | {
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"There are lots of different arrangements, but if you're referring to Qwerty, it's because the letters are offset such that more commonly used keys are next to less commonly used keys. This is because back when mechanical keyboards had arms that flipped around as the keys were pressed it could cause problems if two next to each other were pushed in quick succession. By placing commonly used keys next to uncommonly used ones the chances of this happening were reduced.",
"Real fun fact: the story everyone is quoting here about typewriters jamming has been debunked. [ URL_0 ]( URL_0 ) > While it can’t be argued that deal with Remington helped popularize the QWERTY system, its development as a response to mechanical error, has been questioned by Kyoto University Researchers Koichi Yasuoka and Motoko Yasuoka. In a 2011 paper, the researchers tracked the evolution of the typewriter keyboard alongside a record of its early professional users. They conclude that the mechanics of the typewriter did not influence the keyboard design. Rather, the QWERTY system emerged as a result of how the first typewriters were being used. Early adopters and beta-testers included telegraph operators who needed to quickly transcribe messages. However, the operators found the alphabetical arrangement to be confusing and inefficient for translating morse code. The Kyoto paper suggests that the typewriter keyboard evolved over several years as a direct result of input provided by these telegraph operators. Oh and edit, this line was good: > This theory could be easily debunked for the simple reason that “er” is the fourth most common letter pairing in the English language.",
"On old typewriters, if you would strike 2 keys at the right time too closely together, the striking arms would push against one another and lock up and jam ruining your flow. They organized the keys in a way where it could avoid those lockups in most scenarios based on frequency of hitting certain keys next to each other. This keyboard layout is called \"QWERTY\" based off the first letters in the sequence. There are other layouts, such as Dvorak, which is supposed to improve efficiency and speed up typing so long as you learn that new system, but we're mostly locked into QWERTY now at this point."
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nzyapj | How do companies that specialise in planning & developing suburban cities (Like the Dennis Family in Australia) get permission & funding from the government? | I've always wondered this as in Australia there really is only about 5 or 6 families that are developing the vast majority of our suburban areas, they're all private companies I've always wondered how they are able to literally form brand new suburban areas & even small cities as private companies. Like for example, one of the Dennis families developments, they secured a giant patch of land in the 80's and started building on it in 2002 and now the area is basically a small suburban city, how do they do this? I'd imagine a serious amount of paperwork and money is involved. & #x200B; | Other | explainlikeimfive | {
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"Well, your laws of course vary from place to place, but generally speaking the legal process of taking a large piece of land and making it into smaller pieces is called \"subdivision.\" Your government sets out laws for what has to happen in order to subdivide land. It might be a requirement that a certain percentage of the area be converted into parks, for example. The people trying to subdivide will be required to build roads and utilities, etc."
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nzyk73 | what’s the difference between gasoline and diesel? | Chemistry | explainlikeimfive | {
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"Basically it comes down to the size of the molecules. Both of these fuels primarily come from petroleum. Gasoline is composed of hydrocarbons that have 4-12 carbons per molecule. Diesel is composed of molecules that have 9-25 carbons per molecule. This lends itself to being more energetic per unit volume, so diesel is more efficient on a per-gallon basis. Diesel and gas also differ based on how they are ignited in the engine. Gasoline uses a spark whereas diesel is compressed to the point of ignition (the ideal gas law states that increasing pressure will increase temperature). Diesel, due to this greater thermal efficiency, also has more power and torque, which is why large trucks use diesel instead of gas."
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nzzkib | Why are High Ohm Headphones better then Low Ohm Headphones? | Technology | explainlikeimfive | {
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"Think of the electrical coils inside a headphone as a wound up garden hose. Push water (current) through it and the hose expands and can push other things (electromagnetic field). In a headphone, the coils generate a magnetic field to move a diaphragm back and forth, making sound waves. If you want fine control of the diaphragm, you will need more windings or finer wires in your coils. Both of those generate more impedence for the current to travel through much like water having more resistance when going through a longer or thinner hose. Typically, higher impedence headphones have more complicated coils to generate better sound than lower impedence headphones. This assumes you have the right amplifier to drive them and applies to dynamic driver headphones, not planar magnetic."
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o00uyc | what is the gas inside plant air pockets | For example when you cut open a pepper the inside is hollow. What gas occupies this volume? Similarly, what gas occupies the space in those pod-shaped kelp that you find on the beach. | Biology | explainlikeimfive | {
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"text": [
"Peppers have air inside, the membrane surface of the pepper allows air in slowly as the pepper grows. Hopefully someone else will know the kelp answer."
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o013li | The current housing market despite the ridiculously high unemployment rate. | Economics | explainlikeimfive | {
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"text": [
"Unemployment rate is higher than it has been in recent years, but it's recovered very well all things considered, sitting around 5.8% as of last month. Compare that to the near 15% of April 2020, or the over 6% in 2014, or the peak of around 10% in 2009. As it stands, homebuilders are being impacted right now pretty heavily with logistics and materials, so not as many houses are being finished as quickly as before. Mortgage rates are down, which means more people than previously are looking to buy. Sellers on a whole are not super eager to sell their house and move (potentially to other parts of the country) in the midst of a pandemic with less job certainty on the far end so not as many sales are happening. Ultimately it's less of a \"more people are buying\" than it is \"less sales (of new and existing homes) are happening, so the people who are buying have to pay more to secure the sale\".",
"Investors (often foreign) buying property as an investment. Also now during the pandemic interest rates are at all time lows. Once the pandemic officially ends and everything opens however were going to see high inflation and increased interest rates which means many may be in trouble.",
"1. The unemployment rate in the United States is not “ridiculously high”. Not by a long shot. 2. The number of houses on the market is actually really low, due to issues getting building materials. When the supply of something goes down, it gets more expensive."
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o017cn | What is the Mandelbrot set and why is it important? | Mathematics | explainlikeimfive | {
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"The Mandelbrot set is a kind of map of how multiplication and addition interact with each other in the complex numbers. Complex numbers are, basically, two-dimensional numbers. Whereas real numbers convey the concept of bigness and smallness (magnitude), and forwardness and backwardness (sign), complex numbers expand on this by adding 'sidewaysness'. We represent normal 'real' numbers visually as existing along a number line. Complex numbers exist in a number *plane*. Suppose I give you the instructions: - Pick a number. - Now square that number , i.e. multiply it by itself. - Now take the result, and add your original number to it. - Now take the result, and square it. - Now take the result, and add your original number. - Repeat the last two steps forever. A few different things might happen, depending on the number you picked. If you pick 1, then it goes like: 1 squared is 1, add 1 makes 2, squaring 2 makes 4, adding 1 makes 5, squaring that makes 25... Your number just gets bigger and bigger and grows toward infinity. If you pick 0.1, then squaring that gives 0.01, adding 0.1 gives 0.11, squaring that gives 0.0121, adding 0.1 gives 0.1121... things seem to stay pretty small. If you pick -1, then things are a little weirder! -1 squared is 1, then adding -1 gives 0, squaring that gives 0, adding -1 gives -1, squaring that gives 1, adding -1 gives 0... and we're in a loop. So if you liked, you could count along the entire real number line and check what happens to every single number if you play this square-and-add game with it, and shade it one colour if it remains small or goes into a loop, and shade it another colour if it grows toward infinity. The Mandelbrot set is basically the result of doing this over all the numbers in the complex number plane. Why is it important? For most people, it isn't really. It's just something to marvel at and think \"Wow, how amazing that such an intricate shape comes from such a simple rule.\" But if you're very interested in advanced mathematics, the Mandelbrot set contains hints of a lot of other branches of math. For instance, this add-and-square-and-add-and-square game is closely related to the [logistic map]( URL_0 ), which is used for modelling a lot of natural systems, chaos theory, and even has some connections to the [distribution of the prime numbers.]( URL_2 ) [This Veritasium video]( URL_1 ) is a good overview of some of the different domains of math which are touched by the logistic equation, and its deep connection to the Mandelbrot set.",
"The Mandelbrot set is a set of complex numbers that match a certain condition. To be clear, it's not *important*. But it is *interesting*. The condition that these numbers match causes the shape of boundaries in the function to exhibit self-similarity at every scale, i.e. it's a \"fractal\". You can zoom in on a part of the boundary as far as you want, and you will continue to see the exact same shapes no matter how deep you go. The perimeter is infinite, but the bounded area is finite. Is this useful? Not really. But it's cool.",
"The Mandelbrot set is one of the first iterative math functions calculated and displayed by computers by Benoit Mandelbrot in the 1970s. This is important because it was the start of the study of Fractals and chaos theory in a significant way, and was the first time that computers were used to visualize complicated math and physics phenomena (remember that back then graphics were primitive if you had graphics at all, and most computer output was text only). It's also important in the sense that it's easy to code, generates beautiful graphics, and illustrates chaos in a simple and direct way that makes chaos accessible to a wider audience. At a high level, the Mandelbrot set is a mapping of the behavior of Julia sets, which are both chaotic, iterative math functions.",
"So, the mandlebrot set happens to be an extension, in the complex plane, of something called the 'bifurcation map'. (Don't worry if none of these words mean anything to you, I'll ELI5 the parts that are important.) Basically, think of the mandelbrot set as a big map of how different parts of math transform into each other. Look at it one way, and it's a map of the prime numbers (and thus a map of multiplication and division). Look at it another way, and it's a map of complex exponentiation (and thus a map of how feedback loops work). A bunch of different mathematical processes all happen to have critical points, when their numbers line up with interesting places on the mandelbrot set. So you can actually look at the mandelbrot set, look for an \"interesting\" place on it, and ask \"huh, I wonder what kind of math equation is hidden in this structure?\" - and if you have the right kind of math intuition, you can use that to discover new math, which can immediately lead to new discoveries in physics, biology, engineering, you name it.",
"Well one note of importance is that they're used to create random number generators, weirdly enough",
"Anybody who thinks fractal geometry is unimportant needs their head examined. We live in a world of fractals.",
"So when you look at the graphic for the Mandelbrot set you are seeing where the equation z_{n+1}=z^2 _{n} + C Does not diverge given a complex number C. So for it to diverge as we keep solving the equation over over and over (iteration) the numbers will become much larger and as we iterate out to infinity the solved number will approach infinity. For example take C= 1 as we iterate the number gets bigger. If we start with z =0 and iterate the the next z = 1, then z =2, z=5, z=26, and so forth until it gets really really big. So C=1 diverges and is not part of the set. Now for C=-1 then the z’s you get are -1,0,-1,0-1,… you can iterate as much as you want and it won’t change. So for this we say that z is bounded, and it is part of the set because it does not diverge. What people see when they look at an image representing the set that has all of the colors and stuff they are looking at what values of C do not diverge, and how quickly they converge to a number or become bounded. The Mandelbrot set is cool because there are several relationships that can be seen it. If we look at the bulbs that sprout off and their antenna we can see the Fibonacci sequence in the number of antennae the bulb has. If you take the bulb directly to the left of the whats called the main cardioid it has 2 antenna. The bulb directly about the main cardioid has 3 antenna. Between them is one with 5 (2+3) and between the 5 and 3 is a bulb with 8. If you continue to zoom in the pattern still holds. If we take values on the real number line then we can see a relationship between the Mandelbrot set and what is called the logistic map which is a simple equation that does well to model population growth. The reason the Mandelbrot set is important is because we can see the various relationships it has with other important sets, functions, and numbers (they have even found a relationship with Pi). It’s also graphically beautiful (as most fractals are) and mathematically beautiful for producing these results as a very simple equation."
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o01cyx | why do we always hear about diseases that originated from animals and spread to humans and never diseases that originated with humans? | Biology | explainlikeimfive | {
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"Honestly? It's because we are the ones that are creating news or online information. And this news or information is what we pay attention to WAY more than information about animals. Here's a headline. > Cows in a village all die of random unfounded disease Humanity's response? Geez, shut down that farm and stop breeding those cows! Cows don't travel much, so hey, we've contained the disease! Yay. Problem solved! Compare that with > Humans in a town all die of random unfounded disease That's headlines! Make it the top news story before the humans there travel across the globe and spread it everywhe... oh shit too late. We think about ourselves more than we think about other species. edit: corrected typos."
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o01uad | why were dinosaurs so big? | Biology | explainlikeimfive | {
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"First of all, it's kind of a bias. There were many small dinosaurs but the big ones were really impressive and that makes them memorable. Dinosaurs were on Earth for about 200 million years. That's an incredibly long time and it allows for a lot of species to rise and fall. We think of the era of big dinosaurs without even realising that more time separates stegosaurus and tyrannosaurus and than tyrannosaurus and humans. And we have plenty of large animals today. The blue whale is the largest animal that ever lived. And biologists define megafauna as any animal that is at least 40kg. The overwhelming majority of all life is microscopic or at least very small, just like it was in the age of dinosaurs. But we still have plenty of animals that count as megafauna. Anyways, species grow large when the advantages outweigh the disadvantages. And that can happen for various reasons. One of the big advantages of being large is safety from predators. Another is being able to store a lot of energy reserves in a large body. Big bodies are also very energy efficient in extreme cold. A tiny animal like a mouse is almost all surface area losing body heat. But a large animal has much more volume compared to its surface area and retains heat better. The big disadvantages are that you need a lot more energy to be that large. That means requiring more food. And you can't hide as easily from predators. Take the blue whale for instance. This is the largest animal that ever lived and its an extreme specialist. Very few places can supply a blue whale with enough energy for that enormous body. That's why it travels around the world for krill blooms. These are annual events where microscopic creatures called krill reproduce in enormous numbers. During these krill blooms, blue whales eat enormous amounts of krill in the arctic seas to pack on enough fat for the energy reserves to travel around the world. Their size protects them from the cold water. Their size allows them to pack on enough fat to survive without eating until the next krill bloom. And their size makes them fast enough to make these long journeys in time. Because their journeys will take them from the cold arctic seas to warmer waters to have their babies. And then back again to the arctic for the next krill bloom while they nurse their babies nice and fat to survive the cold. A smaller animal could not have managed this extreme lifestyle. The cold in general also creates a phenomenon called arctic gigantism. As mentioned, larger bodies simply retain more body heat in extremely cold environments. Many arctic species grow larger than their relatives in warmer climates. From the crustaceans on the sea floor to the bears and seals on the ice. Island gigantism is a phenomenon where lack of evolutionary pressure causes size drift. Under most circumstances, being big really isn't much of an advantage. You're more easily spotted by predators, you need more food to survive, and you have a harder time hiding or burrowing. Simply put, there's evolutionary pressure against growing too big. But on some isolated islands that are devoid of predators, species lack this evolutionary pressure. They slowly evolved to be bigger than their mainland kin. Not because it's an advantage but because nothing is stopping them. There's no lack of food preventing them from growing big. No predator that eats the individuals that fail to hide etc. Many large dinosaurs lived during periods in Earth's history where the Earth was extremely fertile. Warm and humid, the Earth was practically a greenhouse. This situation removed the main obstacle to growing really big by providing abundant food for herbivores to grow big on. And with prey animals growing big, predators inevitably followed suit. But it's important to remember our biases. There were a great many smaller dinosaurs. We've found dinosaurs the size of a hummingbird. And we've found plenty of dinosaurs the size of chickens, cats, sheep, horses etc. Still megafauna but not what you're thinking of. Not to mention that dinosaurs weren't alone in their world. There was plenty of life of an unremarkable size that simply wasn't a dinosaur.",
"Scientists used to think it was because there was more oxygen, but recent studies and analysis of amber don't agree with that. The current theory is that because it was warmer and there was more carbon dioxide in the air, plant life grew more. Herbivores, (plant eaters) tend to grow bigger than carnivores (meat eaters) because they are harder to catch and eat. Similar to elephants, giraffes and hippos etc today. Sauropods (long necks) would have evolved similarly to giraffes. The ones with the longer necks could reach more food and had a greater survival rate than those with shorter necks that had to compete with other dinosaurs too.",
"It's partly survivorship bias. The big ones were more likely to form fossils that we'd be able to find today. There's also benefits to being big. A lower surface area to volume ratio helps large cold blooded animals stay warm.",
"All brontosauruses are thin at one end, much, much thicker in the middle, and then thin again at the far end.",
"The vast majority were not. Veloceraptors were the size of chickens. Some were herbivores with an almost limitless food supply and no predators so..",
"Apart from the fact that there were a lot of small dinosaur species, there's also that dinosaurs were more towards the R rather than K end on breeding - lots of offspring, few surviving to full maturity. After all, they (mostly) laid eggs. T Rex, for instance, grew very rapidly from hatching until it was about man-sized. Then there was a pause for 10 years or so, then another growth spurt until it was a one-ton teenager, then a pause, then growth to full size at 5 tons. So a dinosaur ecology had lots of small young running around, filling niches that in a mammalian ecology would be occupied by other species. The advantage to size in this ecology is that the larger you are, the more breeding you do (as with fish today)."
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o027vi | does the temperature of a water change its thickness? | I feel like water thats close to freezing is thicker than room temperature water. Is that true and if so why? | Chemistry | explainlikeimfive | {
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"Yes: colder water is thicker; the technical term is that it's more \"viscous\". [Here's a table]( URL_0 ) showing a couple of diferent measures of water's viscosity over a range of temperatures; higher numbers mean \"thicker\". As for why, hotter liquids have molecules that are moving faster (that's what having a higher temperature means) and so each molecule is less bound by its neighbours and so it's easier for the liquid to change shape faster.",
"In a adittion to the above reply ( nice one btw) you may also wanna take a look on the bose-einstein condensate and the superfluids, some elements like helium, can be freeze into a state that they have no viscosity anymore.Its not meant for 5 year old, but is quite interesting"
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o02pqh | What are antitrust laws? | Because MLB has moved its All Star game out of Georgia, some politicians are talking about removing MLB's antitrust exemption status(i do not want to discuss that law in GA nor MLB's decision at all). I've tried to look up what this means and i just can't seem to figure any of this out. What are antitrust laws? How does MLB's antitrust exemption status effect them and what would happen if it was removed? Aren't there independent baseball leagues out there... but do antitrust laws prevent another league from being as big as MLB in the United States? | Economics | explainlikeimfive | {
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"Ah, way back in olden times, companies would get together in trusts - large companies or holding companies that owned the smaller ones. Or the boards of directors were shared. These companies could: * \"Fix prices\" - set what the retail or wholesale price was to shut out other companies or raise prices at the expense of the consumer. * Rig the market so that new companies can't get started. * Buy up smaller or newer companies to stay big. In the US, monopolies are illegal and any attempt by companies to \"fix\" prices or collude against a competitor is illegal. Sports leagues have been exempt however. The laws and courts have sided with sports leagues (with certain concessions - the NFL can't compete directly with college football). In [Federal Baseball Club v. National League]( URL_0 ): > \"In a unanimous decision written by Justice Oliver Wendell Holmes, the Court affirmed the Court of Appeals, holding that \"the business is giving exhibitions of base ball, which are purely state affairs\"; that is, that baseball was not interstate commerce for the purposes of the Sherman Act.\" Now that exemption exists due to the wording of the legislation as interpreted by the courts. Congress can change it at any time AND since most of the big leagues are monopolies, there are a lot of exemptions carved out for them by Congress.",
"> What are antitrust laws? Anti trust laws are also know as laws regulating monopolies or to be more correct, about monopolistic practices. Now its not illegal to be a monopoly, however, if you are, there are certain things you can't do with the big one's being a) artificially raising prices since you're a monopoly and people must go through you and b) acting in an uncompetitive manner in the industry. There are many exceptions and rules and this is an entire field of business, economics, and law itself. > How does MLB's antitrust exemption status effect them and what would happen if it was removed? MLB has one of the strangest rules on the books regarding any business. Like not kidding, this is weirdly strange. The origins aren't important, but about 100 years ago there was a supreme court case involving MLB and a really strange ruling came out that they couldn't be charged with any antitrust issues. They are generally considered to be exempt from antitrust as a result of that and later cases. Its incredibly odd, but its also irrelevant as you'll see. However... it doesn't really affect them, or you, or the sport or anything, its more a quirk and not something to has any real world effect. > Aren't there independent baseball leagues out there... but do antitrust laws prevent another league from being as big as MLB in the United States? Yes there are a variety of other leagues, and no, for practical and business reasons, this antitrust exemption does not affect that. People talking about removing the exemption are just spewing shit. Now it should be removed, because its nonsense, but it wouldn't have any effect."
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o02q25 | how does an astronaut suit protect the person from the cold of the space and the hot unfiltered radiation from the sun? | Physics | explainlikeimfive | {
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"Someone will do a better job of this than me but here goes! In the word of physics there is really no such thing as cold, there is only more heat and less heat and zero heat (absolute zero). So you are not worried about the “cold soaking in” to the space suit, you are worried about the heat getting out. Heat is the movement or vibrations of atoms and when heat is transferred it means the first atom slows down its vibrations and the second atom speeds up its vibrations. Since space is mostly a vacuum there are not a lot of atoms to transfer that heat too, you just need to create a warm air pocket in the suit and not let that air escape and that’s about it. As for the suns radiation.. it doesn’t take a very thick layer of a dense material like lead or gold to block most radiation, and since you are weightless in space it doesn’t matter if the space suit weighs 250 lbs.",
"Space is not good at transferring heat, because space has no temperature at all (contrary to your post, space itself is neither hot nor cold). The only way heat can transfer in space is through radiation, which is not all that efficient. Space suits have multiple layers of thermal insulation and an outer white fabric layer which reflects a lot of infrared radiation. Heat is usually much more of a concern than cold, because the astronauts generate a lot of body heat when they work. They have to wear a special kind of long underwear with tubes sewn into it. Cold water is circulated through the tubes to keep them cool, otherwise they would overheat and die. I'm not sure what you mean by \"hot unfiltered radiation from the sun.\" If you're talking about infrared radiation, I addressed that above. If you mean other kinds of radiation like UV or charged particles, UV doesn't penetrate the suits, but the suits don't offer any real protection against charged particles or high energy rays like x-rays or gamma rays."
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o02tlm | What is jamais vu? | Can someone explain what jamais vu is and why/how it happens? | Other | explainlikeimfive | {
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"If I understand your question right, jamais vu ,is the opposite of deja Vu, it happens when you feel like it's the first time you're living a experience, even though it's a daily experience. For example, you are washing the dishes, like you done the last 4 years but you suddenly feels like this experience is completely new into your life. It happens when the link of the long-term memory and the perception of the present is Broken, it can happen when you're high, or tired.",
"Jamais vu translates (from French) to \"never seen.\" It refers to the feeling of not recognizing something even though you've seen it before, perhaps even many times. Now as to why, I'm not too sure. Wikipedia cites epileptic seizures as one cause though."
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o03t8q | when taking pictures of a computer or tv screen on your phone, why is the picture occasionally distorted and streaked with odd light effects that vary if you zoom in or out? | I noticed this occurs sometimes when I am recording a video or taking a picture of a tv/computer screen but not all the time. | Technology | explainlikeimfive | {
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"Your TV or computer screen isn't constantly displaying a static image, even when it's displaying a static image; it is getting data for each row of lights and updating them faster than we can typically see (a standard refresh rate for a PC monitor is about 60 hertz, or 60 refreshes per second) - depending on the screen and technology used, it may only update half of the rows (but not like, top half/bottom half, but every other row) at a time. Usually if you take a picture and that's happening, you captured some of the lines in refresh. This is kind of hard to avoid unless you're using a ridiculously fast shutter speed (forgive me, I'm not a photographer so I don't really know what all goes into it, I know some of the terms that are about capturing light for the image) If you're taking video, what your camera is doing is, in essence, taking a picture a certain number of times per second and then playing them back really quickly. So if your capture frames per second is not an exact multiple of your screen's refresh rate, it will have some of that going on through the video. Bonus info: To make this not happen on screen (for instance, if you are shown a picture of a phone screen in a movie it doesn't do this) a movie or TV show's crew will either get specialized cameras that are in sync with the phone's screen, or the editors will go in and add in the animated screen as a special effect."
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o03zry | real numbers in math | Taking a math class and I don’t understand the concept of real numbers, rational and irrational numbers. Please help! | Mathematics | explainlikeimfive | {
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"Let's start with **natural numbers**. Count 'em - *1* apple, *2* apples, *3* apples -- feels pretty natural to me! We probably called them that because it tallies nicely with what we would naturally count in real life. (We also have **integers**, which include negative natural numbers like *-1 -2 -3)* But a-ha! What if I want to describe... half an apple? Well that's still sensible. One might even call it **rational.** We would say you have 0.5 apples. More formally, a **rational number** can be expressed as a fraction, in this case 1/2 (*1* half of an apple, of which there are *2* parts). A number like 0.5 or 1/2 is not 'natural'! But they are closely related to their cousins, the natural numbers. Both of them refer to concrete things we can see in everyday life. One might even say they are rather... **real.** So **real numbers** are just an extended family of natural and rational numbers! So we've met the rational numbers. Does that mean there are **irrational numbers?** Yep, these are the black sheep of the family -- the non-conformists. And more precisely, unlike their rational counterparts who can be defined as a fraction (e.g. 1/2), these irrational numbers ain't gonna conform to no fractions. These are numbers like pi (3.14159265....) or Euler's number (e). You can't quite represent them as a fraction -- they just are! You can approximate them with a fraction, but that's as close as you'll get. Edit (thanks u/NRLight): But as much as irrational numbers are different, they are still part of the family, that is the family of **real numbers.** Finally, you might think, well, we have *real* numbers, does that mean there are numbers that aren't real? One day you might need to take the square root of a negative number and you'll realise 'oh crap, how is that even possible?'. Don't worry, some guy just imagined up a new number that's defined as literally the answer to that question. Then he called it an **imaginary number.** That's it.",
"You are probably overthinking real numbers. Real numbers are any number that is not imaginary. Imaginary numbers happen when you multiply by the square-root of negative 1. This does not exist, but we work around that by assigning that number to the value \"i\" and treating it like a variable (except that if you ever square it, it turns back into -1). We do this because there are practical reasons that you would need to do this in fields like electrical engineering where it's just inconvenient to have a formula not work. But basically, if at any point you're multiplying by the square root of negative 1, you're now in imaginary numbers. If you haven't, you're still in the realm of real numbers. Rational and irrational numbers are both numbers that are not whole (so they have a decimal place): the difference is that a rational number can be represented as a fraction (definitions often say \"ratio\" here, but in this context it is synonymous with how you would use \"fraction\") of two whole numbers. For instance, 0.8 can be written as 8/10 or 4/5 so it is a rational number. Irrational numbers cannot be represented by a fraction without either the numerator or denominator being a non-whole number. If memory serves, the square root of 2 is an irrational number and we can prove that formally in a really simple way. Pi is also irrational, but the proof of that is more complex. There are a few other notable irrational numbers but those are the main ones you'll probably deal with if you're not going into STEM.",
"I have a degree in math, so maybe I can help. So first we have natural numbers that came about from counting things, like 1, 2, 3, 4, so on. This turned into integers, which include negative numbers and 0. Then came along fractions, where, for example, you might want 1 out of 4 pieces of a pie. Eventually this was realized that 1/4 fit in between 0 and 1. Many ancient mathematicians saw math very differently from what we see today. They saw things much more geometrically and much less algebraically. So to them, the only way to get a number between two integers was a rational number. A rational number is just a fraction with a simple rule: that both the top and the bottom have to be integers, so 1/3, 5/2, 100/1, and so on. One important thing to note is that any number that you can write down in decimal form is a rational number. Decimal form is really just a notation where the bottom number is a power of 10. So 1.23 is 123/100. Or 0.918 is 918/1000. So any number you are able to write in decimal form is a rational number. Also, any number that repeats itself in a pattern can be turned into a rational number through a trick, so even .3 repeating, which looks weird at first, can be shown to simply be the rational number 1/3. Also, any integer can also be considered rational as you can just make the denominator a 1. As you can see, pretty much any number you deal with day to day is going to be a rational number. So then the question became does a number that is not a rational number even exist? It would require an infinite number of decimals that does not repeat. Existence in math is a hard and nebulous question, so let's change it to how the ancient mathematicians would see it: is there a situation where a number that isn't rational would be useful outside of theoretical mathematics? Many ancient mathematicians would have given you a resounding no. However, the answer ended up being yes. The most well known of these is a constant we call PI. PI is the ratio of the circumference to the diameter of a circle. It doesn't matter the size of the circle, all circles have a ratio of circumference to the diameter of PI. PI is around 3.14159. However, the 6 digits I wrote don't accurately describe PI, they just approximate it. Using 6 trillion digits wouldn't accurately describe PI. PI is indescribable from just writing numbers down, which is why we use the word PI to describe it instead of numbers. That PI is irrational is hard to prove but it has been proven. Other famous irrational numbers are the square root of 2 and e."
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o044do | DNA in chimpanzees and humans is 99% alike but how is it that bananas share approximately 40-60% of our DNA and what does that mean? | Biology | explainlikeimfive | {
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"Reasonably speaking, a good part of your DNA is about making cells, not the macrostructure you think of as you.",
"A lot of this depends on what you mean by \"shares DNA with\". For example, did you know that the King James Bible and the lyrics to \"Baby Got Back\" both use exactly the same 26 letters to form their words? Did you know that thr Great Gatsby and Fight Club share more than 90% of the same words, if you count each version of 'the', 'and', etc as contributing to the similarity? These are pretty different things from saying \"these two term papers share 80% of their sentences and paragraphs, I think one was plagiarized.\" It's super important to clarify where we draw the lines when saying \"98%\" or \"60%\" or whatever, otherwise you get weirdness like \"wait, scientific American says I share 98% of my DNA with monkeys, but 23andme says I only share 27% DNA with my half-brother? What the hell?\"",
"There are many, many proteins and cellular functions that are required for anything alive. Like the basics of how a cell is structured, how cells divide, how a cell produces energy, all that sort of thing. The genes that code for those levels of things are the same across many, many organisms.",
"Oooh I can answer this! The “humans share 50% of DNA with a banana” factoid is a bit misleading—it’s based on the ~~number of~~ *~~genes~~* ~~we share with the banana plant~~ **average percent similarity between our amino acid sequences**, not the total number of base pairs that are identical. I do not know what percent of DNA we actually share with bananas, but for other plant species it’s more like 10-15%. [Here is a nice breakdown of the accuracy of the \"50% banana\" statement.]( URL_3 ) The “percent relatedness” statistics you hear about are not all calculated in the same way. Some, like the banana plant fact, are based on amino acid sequences. Some are based on numbers of similar genes. Some are based on the similarity of the “exome,” or the DNA that is actually expressed as genes (which is only a small fraction of our DNA). And others are based on whole genomes. We share about 98% of our entire genome with chimpanzees, for instance, but previous studies also placed that number at 95% because they were doing a different calculation. [Here is a short 23andMe post on human relatedness to other species]( URL_2 ) **that compares number of genes** that are similar--note the difference in percentages! 44% for fruit flies, 18% for plants, 92% for mouse, etc. [Here is an example]( URL_0 ) of a time when our \"percent relatedness\" to chimpanzees seemed to change from 98% to 95% due to a study (circa 2004) that used different methods. Compare that to [a more recent article]( URL_1 ) from the same source (2014) that revises the number back to \\~99%. I've done the whole genome comparison between humans and chimps myself (not from scratch though lol) and can confirm that it comes out to around 98% :)",
"Think of this way. All life on Earth shares a common ancestor depending on how far you go back. DNA is an instruction book on how to build life. At some point in past plants and animals had a single simple ancestor with DNA that had instructions for how to make that life. The 40%. This is the stuff we share with plants. Now two members of this ancestor evolved down different paths one became plants and the other animals as this happens their instructions got more complicated but they don’t just throw out the 40% they share they build on top of. This branching happens again and again during evolution but the closer (in time) the branch of two species the more DNA they share as they’ve not had time to diverge as much. Plants and Animals diverged a long time ago where as humans and Chimps diverged only minutes ago in evolutionary terms.",
"It means that we all descended from common ancestors (single celled organisms which lived billions of years ago), which we inherited our genes from. The genes we share with bananas are mostly for growing, operating, and maintaining living cells. Since all known life forms are based on a cellular structure, it makes sense that those genes would be necessary for and shared across all life.",
"DNA is a blueprint for making stuff. For example building a house. A human is a 2000 square foot house. A chimpanzee is a 1700 square foot house. And a banana is a trailer house parked outside. The human house and chimp house are almost identical. They use the same building materials both are lumber frame both have windows. One is a lot smaller than the other but when you're ordering parts to construct the houses, 99% of the stuff is the same. The trailer house though shares a lot of similarities as a human and chimp house. But it uses metal siding, it skimps a bit on insulation, it has wheels. So when you're ordering parts for that trailer house, only about 40% of the stuff is the same. It still needs nails, wood, electrical wiring. The other 60% though are things like gasoline or a steering wheel etc. DNA is all the details, from the parts you need to order or make all the way up to how you put it all together. So a 1% difference is actually incredibly different. And 60% different is astronomical. Just remember the difference between black hair and blonde hair is just a little less paint.",
"Search \"phylogenetic tree\" and you'll find a lot of good info on these relationships, which are directly related to the similarity of DNA sequences across all life: [ URL_0 ]( URL_3 ) [ URL_2 ]( URL_2 ) For example, there are big DNA differences that prevent humans from looking like a banana, but there are lots of similarities...both bananas and humans have similar DNA (genes) that code proteins that carry out cell functions we both have (cell replication, building cell parts, etc). Interestingly, if you only look at one gene, and plug in the DNA sequences of that gene from different animals into special software ([ URL_1 ]( URL_1 )) it will end up building the same tree-of-life due to the small changes that occur over time.",
"It means your ancestors were bananas. Do you like sun?, Do you change color in it? You sir, are a banana.",
"DNA is the blueprint for everything that makes up a living organism. While you might not think you have much in common with a banana, you actually do. If you look at your cells and a banana's cells through a microscope, you could identify a lot of common cell structure and processes. These similar cell structures come from the that shared DNA, passed down for for over 1.5 billion years from our common ancestor.",
"Most of our DNA is taken up by instructions for how to make a functional cell. Almost all life on earth use the same basic instructions for building a cell, reproducing cells, storing sugars and converting those sugars into energy, and converting genetic instructions into proteins. All multicellular life uses the same basic instructions for forming a nucleus, avoiding transcription errors, bonding with other cells in the vicinity, signaling to other cells and receiving those signals, and many, many other mechanics that are absolutely required to make a multicellular organism work at all. That's a lot of instructions. We usually don't think of ourselves on a cellular level, but cells are really, really complicated things. The rest of the DNA is taken up by the instructions that distinguish you from a banana, and that is comparatively minor. (Humans share this amount of DNA with ALL multicellular life. Bananas are just used as the example because bananas are funny.) Of course, the more closely related you are to another organism, the more of its DNA you will have in common.",
"You have basic Lego sets, thematic sets an even robotic sets . Lego sets with the same theme share a lot of pieces, but even between basic Lego and Lego mindstorm you'll find the same building blocks for the main body of the set.",
"**DNA isn't about building a human, a monkey or a banana. DNA is about building LEGO and then assembling them into a human, monkey or banana.** The more similar two things are the more LEGO pieces they'll have in common and the more similar the building plan is. And a whole lot of pieces are *everywhere*. Each animal or plant cell needs to do a lot of the same or simiar things: * produce energy * break apart some things * build other things For example every animal, plant or microbe produces and consumes a molecule called ATP because for cells that's a very handy form of energy. This means everything that's alive has one part in their DNA that produces ATP and one part that consumes ATP. And the same goes for *A LOT* of other substances too. And for everything from humans to monkeys to cats and dogs the building plan is going to be somewhat similar. There's a section for legs, arms, head, eyes, teeth, a heart, a stomach and so on. The details of these sections vary but again, every section for legs is gonna have a subsection for upper legs, lower legs and feet.",
"I've actually always found this claim a bit frustrating as by any normal definition it's just not true. What is implied is that roughly half of a human genome is exactly the same as a banana genome; however this is not true at all. This is because the vast majority of our DNA (98%) is non-coding. This means it does not encode for any protein, though some of it may play some other roles. However, this non-coding DNA is highly variable even within species. There is very little similarity between humans and bananas in this respect. If you look just at genes (1-2% of the genome) and then select only those genes that humans and bananas share (about 60% of those, covering things like biochemical pathways and cell structures) and then look at the protein that is encoded by each gene then there is about a 40% similarity in the amino acid sequence of the human protein and its banana counterpart. Note that this is not the DNA sequence, which can actually vary without the protein sequence necessarily changing. So in actual fact human genomes and banana genome share almost nothing in common at the DNA sequence level, unless you compare the protein encoded by very specific sections of human DNA with matching sections of banana DNA and ignore everything else.",
"I posted this reply to this question 5 years ago, hopefully it helps: EDIT: [link to the previous question, as there are some other answers there that might be helpful.]( URL_0 ) ___ If you wanted to build a motor vehicle, you need an engine, a chassis and a method of transforming the energy from the engine into movement of the chassis. An aeroplane and a car are very different, but both have a chassis, an engine (at least one) and a method of transforming energy into movement (propellers or jets in the case of the aeroplane, a drive-shaft and wheels in the case of the car). Apart from that they don't have many other similarities in how they operate, what they can do or what they are used for. A bus and a car share many more features in common, and in terms of the components they require to work are very much the same (at least much more so than an aeroplane and a car). However, they are very different machines, have different methods of operation and are used for different things. A family Ford and and a luxury Aston Martin are, apart from physically, almost identical machines, especially when compared to an aeroplane or even a bus. Very similar components, similar mode of operation and similar purpose. However, the differences are still very large even though they are basically the same machine, and you would not confuse one with the other. At the end of the day, they are all motor vehicles, because they all have engines, a chassis and a method of using the energy of the engine to move the chassis, but as soon as you start introducing differences between motor vehicles, even relatively small ones, you can get vastly different products. Life is like this too. There are many basic traits that are shared by all life-forms, seen through similarities in DNA. This is how we know they are life-forms, in the same way that an engine, a chassis and a way of transferring energy into movement are how we know something is a motor vehicle. However, differences in DNA, even small ones, result in very different forms of life. So when we say that we share 98% of our DNA with chimps as opposed to 50% with a banana, it's sort of the same as saying that a Ferrari is extremely similar to a Toyota, but has a lot less in common with a fishing boat, even though they're all motor vehicles."
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o09f60 | Why are intramuscular injections given on the deltoid and not on any other arm muscle, like the bicep or something else? | Biology | explainlikeimfive | {
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"It is given to the biggest muscles so the absorbtion is as quick as possible. They could give it to your bicep, but not only would that be uncomfortable, but it would also slow down absorbtion, which is the whole purpose of the shot."
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o0b3zg | Why are all image files four-sided? | Every type of image file I've known is quadrilateral, even if you have a .png of a circle, there are still transparent pixels filling the corners into the shape of a square. Is this because of some technology limitation that only allows images to be this way? If so, elaborate. Or on the other hand was this decision made purely for convenience and no one ever bothered to try making image files in different shapes? Edit: Thanks for the amazing responses guys : ) | Technology | explainlikeimfive | {
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"It is not a limitation of the technology as such, more a concious decision to limit the file formats to rectangular images. This makes it easier to make the file format as all images can be represented as the same type of data matrix of pixel values and defined using only their height and width. And things like the compression algorithms used only works on rectangular images as they can make quite a lot of assumptions about the relative possitions of the pixels. Not all image formats are rectangular though. I have worked with TIFF files that represent the output of scientific experiments where they need to encode all the raw data but this raw data is not collected in a regular rectangular grid. However these formats are very rare and most image applications are not able to display them correctly.",
"Yes, it's convenience. Computer screens are rectangular, and the pixels are arranged in a grid. You could create a circular screen and a circular image, but why would you?",
"As far as I know there are 2 methods of dealing with digital images. One is raster graphics and one is vector graphics. So lets say you have an analog photography that looks something like that: [ URL_1 ]( URL_0 ) (In case you can't see it or don't want to click the link, it's a simple house drawn with a bunch of straight lines) Now you want to send the information to a friend but you can't send the photo itself but are only able to describe it to them. So the raster graphic approach would overlay that image with a grid and for every cell of that grid it would determine one color and one color only and tell the list of colors and grid positions to your friend. Then you're friend would draw the grid, color it's cells et voilà your friend would have a copy of your picture. Now for that approach using a rectangular shape is very convenient as you only need to give them two coordinates x and y then afterwards you could basically just name colors and your friend might fill them in left to right, top to bottom, for example. So sure if you cut off the areas that you don't need for a circle or that are blank in my example, you'd have less pixels to worry about, but you'd also need to supply your friend with an additional information of where the pixel actually is either on their screen or relative to idk the first pixel. So in most cases you might end up with more information that you need to deliver not less. And that approach is so successful that basically all modern image recording devices use that. Meaning an image is created by having light pass through the lens of a camera that is directed on a grid like pattern, where sensors determine the color by the intensity of the light that passed through a red, green and blue filter for each of those picture elements (or pixels). As well as the vast majority of image displaying devices, like computer monitors which also operate on a rectangulare shape that is subdivided into pixels that change change their color. Now that we've gotten to know raster graphics, the alternative to that is vector graphics. So instead of telling your friend the color and position of each pixel, you tell them to draw simple geometric shapes and where they start and stop. So you basically write them a recipe: \"put your pen at coordinate (0,0) and then draw a straight line to (0,3) with a thinkness of 2\". That way you avoid to tell them any of the blank spaces and if you want to you might even work with general descriptions such as \"half the screen size\" to even avoid having to tell them specific coordinates as to where to place the pen. Which is massively interesting when you want to be able to present an image at different sizes. Because doubling the size of the image is easy, just double the length of the lines, done. Whereas for a raster image, you don't need to know anything about what is displayed on the image and therefor also can't really double it without having it look pixelated. Because you simply drawn the pixels bigger, without adding additional information to make it smooth again or guessing how it could look like. The downside is that you need to describe your picture really well so every line and it's relation to other lines has to be noted somewhere which can get messy real quick. Now those are basically a list of commands how to draw an image rather than the image itself and once you want to see it you still have to feed it to something that essentially translates it to a raster graphic (computer monitor), but as said you can easily rescale it up or down to make it beautiful no matter the size. Edit: fixed some spelling errors."
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o0c76y | What makes haemoglobin toxic to the human body? Isn't it essential for carrying oxygen in our blood? | Biology | explainlikeimfive | {
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"Haemoglobin is, as you say, essential for carrying oxygen. But technically, we do not have haemoglobin in our blood. Haemoglobin is a protein that is bound in erythrocytes, red blood cells, and that is very important. Another protein is haptoglobin, that forms a complex with free haemoglobin. This happens when a RBC is destroyed, and haemoglobin is released in the bloodstream. This happens all the time, and is mostly no biggie, the haptoglobin-haemoglobin complex will just go to the liver, to be broken down. However, if enough RBCs are destroyed, there won't be enough haptoglibin to bind haemoglobin, and you end up with free haemoglobin in you bloodstream. Free haemoglobin binds very easy to oxygen, that's the intention, but this oxidative property can lead to inflammation and tissue damage if it is not contained in the RBC. All in all haematology is a very complex subject, but to sum it up: haemoglobin in RBCs is not the same as haemoglobin in blood"
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o0czwt | Swatting a fly... a slap or a punch? | I was asking my colleagues why a slap style swat would be better for killing a fly mid-air than a punch. Some thought it would not be more effective, none of us could give a suitably physics reason to support our thoughts. Can you help? EDIT added "mid air" | Physics | explainlikeimfive | {
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"Neither, you clap. You can only move your hand so fast, and it's typically slower than the fly can dodge. Clapping effectively doubles the speed you close the distance between the fly and your hand. Plus, you need to smack the fly *against* something to kill it or else you're just kind of tossing it. If you want to kill the fly, clap. If you want to shoo it away, slap. If you want to look like a nutjob, punch.",
"Neither. And not just because of air as people are suggesting. It's airborne, so there's no resistance to keep the force of your swing from transferring into it and just sending it flying. What kills you when you hit the ground from a skydive isn't just ending the ground, it's the sudden stop where the rest of you keeps going. You're essentially being crushed by rapid negative acceleration. If the ground were made of some breathable gelatin that slowed you signifying slower than top soil, you'd be fine. So instead you rely on something like a table, wall, or your lap to forbid the fly from being thrown with your swing and to force the fly's exoskeleton to crumple under the force resulting in a crushed fly.",
"Well slapping would mean your hand is open meaning more surface area to hit the fly with. So based on that alone I’d say slap. Beyond that the differences are pretty minimal.",
"Neither will kill a fly. The faster you try to hit it the more air you'll be forcing at it and blowing it away from your hand. You won't hit it with enough force, they have a sturdy little exoskeleton",
"Either way, the mass of the fly compared to strength of the materials (exoskeleton) it's made of mean that you'll just knock it through the air, not kill it. As u/Belazael said, the size of the surface area you're hitting with affects the odds of hitting it. Punch or Slap, you'll probably not even knock it silly (er)."
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o0dchh | How and why do some banks offer annual interest on the money in your savings account? | Economics | explainlikeimfive | {
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"Banks make their money on loans and mortgages. In order to sell those, they need money to actually give out. They do this by incentivizing other people to save their money with them, so they can use some of it for loans. In return, the people whos money they use get a little cut of the profit from those loans in the form of interest on their savings account.",
"How? By lending that money to other people at a higher rate and keeping the difference. Why? So you'll keep your money with them so they can lend it to other people at a higher rate and keep the difference ;-)",
"Banks have a few ways of making money: Interest income, which is the money they make by lending people and companies money to buy things. Mortgages for a house, credit cards for every day things, business loans, etc. They also have non-interest income, which are the fees they charge for services (like money orders or wire transfers) or overdraft, gains from selling mortgages or securities, and things like that. To make that money, they have to attract customers. Without customers, they have no money to lend out, and nobody transacting with the bank who will use the services they charge a fee for. So the opposite side of income is expenses. Most people can think of employee salaries, buildings, technology, etc., which are referred to as noninterest expenses. Interest expense is the money that is paid to customers for leaving their deposits in the bank. Generally, the more money you are willing to bring to the bank and the longer you are willing to leave it there, the better your interest rate will be. So the banks basically use interest rates as a marketing tool to acquire customers, so they can make loans and charge fees."
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o0dt3i | How do Artificial Neural Networks work? | Technology | explainlikeimfive | {
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"Let’s think of something an artificial neural network could do. How about predict the weather? We’ll just tell it to try and figure out how warm each day will be, to make things easier. So the output we’re looking for is “tomorrow’s high temperature.” Now we need to give it some inputs. We can give it things like the last 5 days’ high temperatures, and maybe the temperatures from a city to the west. You could tell it last year’s temperatures for the same day, or maybe the last 5 years. Just any information that you think would help. The system makes its first guess, based on all that data, added/ subtracted/ multiplied together. Then tomorrow we see how close it is to correct. That information goes back into the system, and the system adjusts its math to try and get closer. Over time, the system starts “learning” which data matters, which data doesn’t, and so on. In this example, the learning process can be slow, since it takes a full day to figure out how right it was about its guess. But we could give it all the information from a year ago, and let it guess its way through all the information we have just as quickly as it can do the math. In short, then, artificial neural networks are just self-adjusting math equations, and are only really as “smart” as the information they’re given.",
"It's basically large scale trial-and-error. You have a bunch of individual nodes. Each node takes as input some number of numerical values. It then adds them together and multiplies it but a number called the \"weight\" then produces an output. By having lots of nodes which feed into each other, and by tweaking the weights to get the desired output of the system as a whole (when comparing it to known data), it can become good a predicting and classifying unknown data correctly."
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o0e7tv | Why does bleach make things white? | Chemistry | explainlikeimfive | {
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"Most dyes are rather complex organic molecules, which need to have a very specific structure in order to have color. Bleach is just a strong oxizider, it oxidizes those molecules and alters their structure enough to make them lose their color."
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o0ehb3 | How does a hailstorm in 80F weather work? | Earth Science | explainlikeimfive | {
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"Temperature at sea level is different than the temperature at cloud level. As long as the trip from the clouds to ground level isn’t flash boiling the rain or hail the storms can form properly"
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o0evad | Why have most prices been continuously increasing for several decades but wages haven’t been at the same rate? | Economics | explainlikeimfive | {
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"European here. From my viewpoint the US seems to have chosen to give most of the increase in national wealth to the top 1% of earners rather than the lower 50% American exceptionalism or something.",
"Rich people used their money to bribe politicians into changing the rules so they could keep and make more money. Then they did it again. And again. Then they used that money to buy all the major media everythings and used THAT power to convince all the poor and middle class people to fight each other for the scraps left over instead of realizing the problem was those rich people.",
"That's what capitalism does. When everything is controlled by markets, those with the most ability to buy will buy all the food and land, then hold everyone else as hostages. Wages haven't increased because the ownership class owns your wages, and if you decide to fight them on that they send out the cops to kill you. The only times things have ever gotten better for the people who work for a living rather than the people who own for a living are when the workers realized they are more powerful together than their masters could ever hope to be.",
"There's a lot of what I'd call \"folk economics\" that makes its way into the public discourse. If people see a price increase, their \"folk economics\" tells them its bad. Based on the data I've seen, though, wages have basically kept up with inflation for the last 50 years or so. Before that, there was real wage growth, i.e. the inflation of labor prices was higher than inflation in general.",
"Wages *have* been increasing, but only for a few people. All of the increases in wages have gone to the top fraction of a percentage of people. CEOs today are making about 1000% more than they were thirty years ago. Average worker pay has increased about 10% over the same time."
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o0evi3 | How come moving on something such as a horse or bike for example feels faster from your point of view than when playing on a video or watching someone else? | Physics | explainlikeimfive | {
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"Because it's impossible to measure \"absolute\" velocity (unlike acceleration), you always have to measure it relative to something else. Our brains aren't great at this, and our perception of speed is *heavily* biased by what's moving, how big the moving thing appears to be relative to us, how fast it's moving relative to us, how its motion affects us, and the state of our emotions at the time. For instance, if you're in a skyscraper looking down at a car on a street below, it wouldn't look like it was going all that fast, but if you were on the sidewalk and nearly hit by that same car, it would seem much faster. Adrenaline, perspective changes, perceived threat - they can all make things seem faster or slower than they actually are."
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o0f0z2 | Why are air quality readings in Canada and the States so different? | So I’ve recently seen that apple has put air quality readings on their Weather App. I used to travel from Toronto to LA allot and so I was curious as to the difference in air quality but could see AQHI was used in Canada and AQI in the US. Is there any at to compare these two and what is the difference? | Earth Science | explainlikeimfive | {
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"From the Canadian Government: > The Air Quality Health Index (AQHI) reflects current knowledge of the health effects associated with air pollution. The traditional Air Quality Index (AQI) is based on air quality standards and takes into consideration both environmental and human health concerns. AQHI is looking at health science. AQI is looking at legal standards. So AQHI is \"will the air make you sick\" and AQI is \"Is the air polluted more than is allowed by law\"."
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o0finl | Why does tapping/denting the edge of an unopened jar lid make it easier to open? | Other | explainlikeimfive | {
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"By compromising the jar's airtight seal you allow air to enter and the pressure inside will equalize to the pressure outside. You'll no longer have to work against the weight of the atmosphere."
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o0fkci | how can cancer be both caused and treated by/with radiation? | Biology | explainlikeimfive | {
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"Different levels of radiation. Radiation that causes cancer is when you get enough radiation to damage DNA to the point that the cell repair mechanisms can't recovery it, you get a mutation, and runaway cell growth follows. Radiation to \\*treat\\* cancer is much higher dose...it's radiation so intense that it kills cells, particularly cells in the middle of reproduction. You target it fairly tightly to a specific region (the tumor) to preferentially kill the cancer cells. You're not really worried about mutating the cancer cells, they've already jumped the shark, you want to kill them.",
"Radiation can cause damage. A little bit of damage to a cell's genetic code can cause mutations that (eventually) cause cancer. These mutations lead the cell to make copies of itself outside the body's control. The cell \"goes rogue\" as it were, and starts growing into a mass called a tumor. This in itself can create problems, depending on what type of tissue the tumor is made out of or where it is located. For instance, a tumor made of cells that produce hormones can cause nasty effects throughout your body as your hormone balance gets all out of whack. Or the tumor might interfere with the healthy tissue around it (e.g. cut off blood supply, press on a nerve, or what have you). One tumor can be okay, though, if it's not too badly placed (and not made of the wrong type of cells). For instance, a tumor on your skin is unlikely to cause serious problems directly. The real problems start when the tumor become *malignant*, which usually when we properly start calling it cancer. What this means is that cells start to break away from the tumor, and travel trough the blood or lymphatic system to other places in the body, and then settle there and grow new tumors. Once that happens, you can start having tumors grow all over your body, which is more likely to cause problems (even if the original tumor was \"well-behaved\"). The mutations that cause tumor cells to become malignant can also be caused by radiation (but also by other types of damage to the cells' genetic code). So that's how radiation can cause cancer. How can it be used to treat it? Well, a little radiation can cause a little damage, but more radiation can cause more. In particular, enough radiation can destroy cells. So, if you know where the cancer cells are, you can target them with radiation that destroys them. You cannot target individual cells with this - the technology isn't as precise as that. But you can use it to target tumors. Ideally this radiation treatment will destroy the entire tumor, or else at least reduce it to almost nothing. Often some healthy tissue gets destroyed as well, as it's better to err on the side of destroying too much and make sure you get the whole tumor, rather than destroy too little and leave too many cancer cells alive. Radiation treatment is an alternative to operating, and in some cases this is preferable. It's less invasive and doesn't require surgery, but that doesn't mean it's without side effects as you do often end up damaging healthy tissue too. So in short, it's all about the dose of radiation and targeting it to the right place. A low dose may cause damage but not kill cells, and that can lead to cancer. A high dose of radiation in the wrong place could kill you or make you very sick. But a high enough dose of radiation in the right place can get rid of a tumor."
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o0goj1 | The relationship between stall speed and angle of attack? Can we just reduce Angle of Attack instead of adjusting air speed? | For reference, I have studied King's Ground School and this video: URL_0 * I'm starting with the equation that Lift is proportional to Angle of Attack times the Airspeed. Meaning that if one goes down, the other has to go up to maintain lift. * My assumption is that the equation above assumes regular airflow over the wing. Therefore, stalling happens when you hit a certain Angle of Attack because the air ceases to stick to the top of the wing. That angle is labeled as the Critical Angle of Attack. We can't increase airspeed to compensate because this would not restore regular airflow. This is an upper limit of sorts. * So my understanding is that stall speed (Vs) is the minimum speed that you can fly to maintain lift = weight? For any given Airspeed, can we reduce the Angle of Attack to prevent stalling? * If apparent weight on the aircraft increases (e.g. while turning), why does stall speed increase? Is it because the previous the previous stall speed is no longer sufficient to maintain lift? | Physics | explainlikeimfive | {
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"Yes, when a stall occurs the immediate response is generally to push the stick and reduce angle of attack (it also tends to increase airspeed). Usually stall is a concern when climbing to altitude, so yes you could reduce angle of attack (to a point) but then you'd never climb to your desired/cruising altitude. Taken to an extreme, if you're just going to sit on the ground, you won't ever stall, but a car is a much less expensive way to get around. Critical angles tell you the maximum climb rate of a given plane, which can be important for knowing if you can climb above an obstruction for say a strip in a narrow valley or you're dogfighting or something similar (so yes you could reduce angle of attack, but in both cases you have a very good reason to really want to be climbing at that moment). The stall speed increases because you need more lift as the apparent weight increases. Yes."
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o0h88u | How does the computer physically store information in the memory (RAM)? | I know that the RAM is for storing temporary information that can be accessed very fast. How is this information physically stored? I do web development (nothing low level like Assembly) and I use variables to store information but how is that physically stored? Are there any elements that hold the electric charge or in any other form? Is it similar to how information is stored on a hard disk which are (as far as I know) magnetic slots that can have a direction? | Technology | explainlikeimfive | {
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"RAM typically uses capacitors and transistors to hold onto an electrical charge. A \"high\" electrical charge (above half a volt) is a 1 and a \"low\" charge is a 0. It's much faster than reading and writing to a hard drive, but is volatile (only works while the computer is powered)."
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o0i9fo | Why are peanuts and almonds oily inside? What purpose in nature does nut-oil serve? | Biology | explainlikeimfive | {
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"Oil is fat. Fat is, like in animals, a store of energy. Legumes, nuts, and seeds are all seeds--that is, plants grow from them. Seeds need energy to grow their first roots and sprout their seed leaves. Oil in the seed provides that."
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o0ivby | When a bee hive/ant colony is destroyed, what happens to the remaining bees/ants? | Can they survive independently without an existing structure or will they just die? Will they search for a new colony and, if found, will they be accepted? I understand it may be speculation because we can’t exactly follow an ant around for a week. But if anyone knows how they function outside of society, it’d be interesting. | Biology | explainlikeimfive | {
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"This was written by another Redditor and applies to both bees and ants. & #x200B; > It depends on a few things: **The queen was not killed:** They will attempt to rebuild the nest **The queen was killed, but some queen larval cells are still intact:** The workers will continue to raise the new queens. The first one to emerge will become the new colony queen and mark all of its sister queens for death by painting their cells with a pheromone which causes workers to attack those larval cells. The bees will attempt to rebuild. **The queen was killed, but some worker bee larval cells are still intact:** Surviving worker bees will select a worker bee cell and feed it royal jelly to grow a new queen. Larvae which grow into bees are essentially neutered by how nutritious their diet was as a larva. If fed royal jelly, which is higher in protein and fat, any young larva could develop into a new queen, mate, and the colony could recover. **The colony was completely obliterated:** The surviving worker bees might try to rebuild, and without a queen to suppress their reproductive processes, will begin to lay eggs. These eggs are not fertlized by a male however, and are unlikely to develop into new bees. Even if they do the offspring will only be male drones which are useless. The colony, along with any surviving bees, will be finished. In most social bees, new colonies are only formed by newly fertilized queens and only at a specific time of year. It is unlikely an established colony would ever move in response to a catastrophe.",
"Antkeeper here. ~~I don't know much about bees, but afaik they can only have one queen. Once she dies, I guess the other workers will keep doing their daily business, but eventually the colony will die out.~~ (There's a better answer about bees in this thread written by /u/CurveOfTheUniverse. Refer to that one for the answer about bees) For ants however there's many different possibilities, depending on the species. * Monogynous colonies: single queen. Once she dies, the ants might still live for a while, but the colony will also die when they die of old age. They do not search for a different colony to join. Lasius niger (European black pavement ant) is an example. * Polygynous colonies: multiple queens in one nest. Once a queen dies, there's still others to take over their job. Example: Myrmica rubra (European red stinging ant) * Oligogyne colonies: the workers will tolerate multiple queens, but the queens themselves won't. So they stay in separate chambers. DNA-wise you could say that multiple colonies live together in the same nest in this case. Once one of the queens dies, the workers still work together with the others. Example: Lasius flavus (yellow meadow ant) . Then there's some very weird exceptions, such as species that can lay fertile eggs themselves, without even having a queen. E.g. Pristomyrmex punctatus. But this is definitely not a general rule and more of a freak-accident in the ant-kingdom. In captivity it's also possible to introduce a new queen to an existing colony if the colony is still very young. But the chances of success are very slim. I doubt that it ever happens in the wild. Edit: note that the other answer that was given about bees definitely does **not** apply to ants. Except for species that allow inbreeding (few do), it is impossible for a colony to generate a new queen that will join the own colony. Edit2: oh, and there's also parasitic ants! Two types come to mind: * Social parasites (E.g. lasius fuliginosus): These will intentionally invade a nest, kill the queen, and take over its place! She will lay eggs herself, and the workers of the existing colony will take care of them and still forage food. * Slave makers (E.g. Formica sanguinea): these will steal workers from other colonies and add them to their own as slaves. So if a colony is without a queen, in this case you could say they \"joined\" A different one indeed."
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o0ixbl | whether ion technology hairdryers do anything | Half of the hairdryers in the shops are "with ions", promising that they dry your hair gently, without frizzy ends, and faster than regular hot air. Do they actually do any of that? How? | Technology | explainlikeimfive | {
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"*not a hair drying expert but I know some stuff about ions, here's my take on the situation. The theory with ionic air movement and improvements in how it dries your hair are that the removal of ions can reduce static electricity. I know this works on a purely scientific level because I do it everyday at work. But when I do it I'm trying to remove my new quantities of static electricity in micromanufacturing processes, we're talking about stuff that's measured in nanometers an angstroms. Seriously, literally microscopic stuff. But the real question is, will that benefit your hair? Maybe. I tend to think not, but the manufacturers of them would have you believe otherwise. If you got extremely frizzy hair maybe they might help, but I doubt it. There's just too much too many factors at work in drying your hair, air speed, air pressure, relative humidity, air temperature, ambient temperature etc etc etc. I can't see an ionic hair dryer producing radically different results than a normal one."
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o0jyak | Why are different instruments tuned to different keys? | A violin is tuned to the key of C. A french horn is tuned to the key of F (sometimes). What does this actually mean? Does an F played by a french horn sound the same pitch as a C played on a violin? If so, how is that possible, given that they (presumably) have the same frequencies? If not, what does it actually mean, and why are the instruments like that? | Other | explainlikeimfive | {
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"This is called transposing. It is done mainly for wind and brass instruments to keep fingerings consistent. Transposing instruments are said to be \"tuned to a key\". If a clarinet is tuned to A, then when the clarinet plays a written C the sound produced will be an A.",
"For brass instruments, the \"key\" refers to the fundamental pitch they can play without pressing any keys, or in the case of the trombone, with the slide fully in. So a French horn will be able to play an F and all its harmonics (F, F, C, F, A, C, etc. ascending) in its open position. For woodwinds; it's slightly more complicated, but they all have fairly similar fingerings where most fingers depressed will play a written C, and then a C major scale can be played lifting up one finger at a time in order. This sounds like a C major scale on flute, but the same fingers play a Bb scale on tenor sax, Eb scale on alto sax, and a Bb scale in the second register of a clarinet, so those instruments are referred to as being in Bb or Eb. This makes it fairly intuitive to switch between the instruments and read music when it's transposed for them.",
"It basically comes down to making it easier for the player to read and switch between instruments. Brass and woodwind instruments all follow the same fingering/overtone pattern (within their family) starting on the fundamental note of the instrument. And the length of the tube determines the fundamental note. Now, it's not *necessary* to make them transposing instruments, meaning the written note sounds different. You could write the true note for each instrument. But doing that has two consequences. One, some instruments are in ranges that don't sit nicely in a treble or bass clef. So players would either have to read in less common clefs like alto or tenor, or read notes on leger lines really high above or far below one of the common clefs, which is tough. Two, it would be really difficult to switch between variants of instruments like the trumpet or saxophone that have multiple transpositions in their family. You're basically faking the note for the player so they can use the same fingerings on different versions. As an example, the written note G on a saxophone is played with the three fingers of the left hand regardless if it's an alto (sounds as a Bb) or tenor (sounds as an F). That is so the player can easily switch between the two without completely relearning fingerings for each. Basically it takes the complexity of different instruments having different fundamental tones, and puts it onto the composer/arranger instead of the player. As to the second part of your question, the key of the instrument is the note that sounds when it plays a written C. So when a French Horn plays its written C, it sounds like an F for the piano (concert pitch)."
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o0jyy0 | When I’m on speakerphone, how does the person I’m talking to not hear the videos that I’m playing and hearing while we’re talking? | Technology | explainlikeimfive | {
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"Because the phone knows what sound waves it is putting out, and chooses not to transmit them. The computer inside your phone knows that the sound the speakers are putting out “looks” like, the sound waves, so at when it is also receiving sound to send on a call it is “looking” for those same waves getting picked up again. When it spots them, it removes that sound data from the data it is sending along to the other phone on the call."
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o0kcy4 | Why are the sugar in fruit good for you but the sugar in candies bad for you and make you gain weight? | People use "sugar is not bad for you because fruits have sugar" a lot. So i wanna be prepared next time someone use this line on me | Biology | explainlikeimfive | {
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"It's not just about the sugar alone - it's about \"a piece of fruit\" vs \"a piece of candy\". One medium apple has around 19g of sugar according to the FDA, along with 4.4g fiber and 15% of your daily vitamin C, plus a handful of other vitamins. It comes in at around 95 calories. One Snickers bar has 30g sugar, 1g fiber, and almost no vitamins at all. It's also got 14g of fat (22% of your entire daily limit), with 5g saturated fat (25% of your entire daily limit). You'll get that for 280 calories. So: the fruit has less sugar, less calories, more vitamins, and will keep you full longer - while the candy has more sugar, more than double the calories, massively more fat, no vitamins, and will leave you hungry sooner. Even though the apple \"has sugar\", it's still far better for you.",
"Surprise, surprise: the sugar in fruit isn't any better for you than the sugar in candy. And in fact, humans have bred fruit to have *vastly* more sugar than they did in nature. Now, *fruits* are better for you than candy, but that's primarily because they don't contain as much sugar as candy does, and fruits typically have plenty of fiber and vitamins that you'll get along with that sugar. One of the biggest scams in human history is the idea that fruit *juice* is good for you. You hear about people trying to avoid refined foods. Well, fruit juice is literally the process of squeezing out nothing but the flavor of a fruit and eliminating almost all of the nutritional benefit. It's Kool-Aid, made by a tree. (Yes, there's still some vitamin content, but the massive amount of sugar completely overwhelms any health benefit you'll get from fruit juice.)",
"Sugar in fruit is usually balanced out by the amount of fiber and antioxidants that they have. The fiber in an apple means that it is absorbed less quickly than sugar in a Snickers Bar, even though apples have 19 grams of sugar as opposed to the 20 grams in the candy. The issue of fiber is also why eating a whole apple is better than drinking apple juice.",
"Sugar has received some bad press in recent years, but not all of it deserved. There are a couple factors coming into play here. Let's talk about 3 big ones. 1. The amount of sugar your body actually needs on a daily basis 2. The state in which that sugar is found (is it simple or complex) 3. Other nutrients that are also found in that food First and foremost, sugar is sugar. Sugar in apples and bananas is going to do the same thing as sugar in a Twinkie and Moon Pie. But you do need to understand how much sugar is actually in each one of those things. To give a theoretical example you might find that one bite of Twinkie has the same amount of sugar as an entire apple. This would mean that eating that two pack of Twinkies gets you a lot more sugar than the apple. I'm not sure of actual sugar contents. Second, how much of that sugar is simple sugar and how much is complex. Sugars are often found as lone molecules (monosaccharides), paired up in two's (disaccharides), or in longer chains of complex molecules (polysaccharides). Simple sugars are the first two. Complex sugars are things like starch. Simple sugars are good for getting quick energy now, whereas complex are good for storing energy for later. You need a diet with both, but generally speaking you don't want THAT much simple sugars all at once. It can overwhelm your body, increase sugar in the blood stream which can cause other problems. Third, you need to take into account of other nutritional benefits from foods. Does your food just have a lot of sugar? Does it have other nutrients with it that are important. Cold cereals get a lot of flak in recent years, but most cold cereals are infused with other nutrients. Ever read that label on your Fruity Pebbles and realize that you're getting tons of riboflavin, vitamin B12, zinc, and other things you don't generally get in other places now-a-days. While it might be better to have a lower simple sugar content, there is good to having foods that artificially/naturally have other nutrients your body makes. Some of those nutrients your body CANNOT make on its own. TL;DR So to make the long story short, it's less about sugar being good or bad, but more quantity. Would you serve someone 15 lbs of pasta? No. It's obviously too much. We innately know that would not be good for our bodies. ***But diet is more than just the quantity of food you eat. It is also quality.*** *An apple may end of being the same quantity of food as a Snickers and a bad of chips, but the quality of the food is much different.* Fruit has a better balance of nutrients and complex sugars than the sweet treats we know are bad. They also have more naturally occurring nutrients that make the apple beneficial."
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o0kl5g | How do Rappers flex so much physical cash ? | How do rappers withdraw like 50K/100K cash ? Do banks allow people to withdraw as much as they want to ? ATM’s don’t even have that much money, do they have to ask someone that works in their bank ? | Economics | explainlikeimfive | {
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"If you want a pile of cash you can call your bank and order it. It may take them some time, but they'll get you your stacks. If you just want to make a video you buy prop money.",
"Its not real my dude. You can buy fake money for movies or whatever right off Amazon. It looks convincing enough for a music video The nice cars are usually rented as well",
"Well my guess is that a lot of what you see (especially in mainstream videos) is fake money produced specifically for use in movies and music videos. However, if you are referring to more underground/ drill style videos the explanation is that the way some artists make money is by selling drugs which is almost exclusively done in cash and often left unbanked anyway.",
"From a commercial point of view, thats really not that much cash. When I worked cash control for a medium sized grocery store, we'd routinely deposit $100k in cash to the bank daily. That was the output of a single store, and cash was only about 10-20% of our business. If a production studio wants to make a video with a ton of cash laying around, its very easy. First, you can just strait up order currency from a bank. You specify exactly when and where you want it delivered, and what denominations you need it in. The bank will probably charge you a fee on top of it, but thats just the cost of doing business. If that's not sufficient, and you need like a pallet of cash, you just need to make the stuff the camera is going to see look convincing. First, you build a hollow box on top of the pallet, but a little smaller. That way you don't have to fill the pallet with cash. Then every cash bundle that isn't going to be touched on camera can just be a stack of green paper with a real bill on top. If your actors need to pick up a few stacks and flash those about, you put a few real stacks of cash on top and point them out to the actor. They know to only grab the real ones while on camera. Lastly, you never zoom in on the cash. Pulled back shot of the pallet of cash first, cut to a close up of real cash, cut to another pull back photo. Your audience is totally convinced and you only needed a few grand in real cash to pull it off."
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o0l0o0 | how do oceans become land? For example, the Alps, and other parts of Europe used to be seabed, but now it a massive mountain range? Are there any other regions undergoing uplift too? | Earth Science | explainlikeimfive | {
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"Someone else has commented an answer i think makes sense, however, im intrigued by your example - The Alps used to be seabed? is that true? seems a bit odd to me.",
"Tectonic plates. If you’re familiar with what those are, their movements slowly shape the planet by moving away or into each other. Mountains, for example, are tectonic plates wrinkling when shocking with one another.",
"Hold your hands out in front of you with your fingertips touching. Push your hands together. What happens? Your fingertips move upwards, forming a peak. This is essentially what happens. Massive rocks called techtonic plates collide with one another which forces one over top the other one which creates the mountains.",
"Basics: the crust of the planet is made of large plates that float on the mantle. These move based on heat patterns within the mantle. When plates collide they generally do one of two things: one sinks beneath the other, or they both are forced up against each other resulting in mountain ranges. It's generally why we see mountain ranges where two plates meet, such as the Indian plate and Eurasian plate causing the Himalayan mountain range, or the South American and Nazca plate forming the Andes. Land can be formed if a plate sinking forces the rising plate above sea level.",
"Tectonic plates have been mentioned, in north there is another force callled ice age rebound. The ice caps during ice age were compressing the local crust, which is still recovering. There are areas in Finland where ground rises faster than sea level due to global warming.",
"It's mostly due to tectonic plates shifting over time. These are gigantic separate chunks of rock on Earth's crust. Because the core of the planet is molten, there is a lot of moving and shifting of these plates. Sometimes they push against one another, sometimes they go over or under one another. When those movements happen, some parts of the crust settle while others are pushed up. That pushes the land masses on top of these plates to settle at higher or lower heights."
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o0l1fo | What is the literal meaning of, "the exception that proves the rule?" | I understand the colloquial meaning behind the phrase, but I don't understand the literal meaning. Why does an exception to a rule somehow prove the rule is true? Wouldn't that simply prove the rule is false? | Other | explainlikeimfive | {
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"The phrase is actually used incorrectly most of the time. It refers to when a rule isn't specifically stated but an exception is, and from the exception you can infer the rule. For example \"Restaurant is Open for Brunch on Sunday\", or a nightclub advertising \"No entry fee for women on Friday night!\" From these exceptions you can infer that the restaurant doesn't serve brunch on other days of the week and that men would have to pay for entry to the club on Friday.",
"If you see a sign that says \"No Parking on Sundays\", it implies that parking is allowed every other day. If parking was prohibited for any other day, it would also be put on the sign. Thus, the rule (\"parking is allowed...\") is proven by the exception (\"... except on Sundays\").",
"It's not that it's proving that the rule is universally true or always correct, but that by deliberately pointing out the exception, you are validating the existence of a baseline rule (in the sense of a rule-of-thumb or a pattern/normal that is almost always true; this isn't about physical laws of the universe). For instance, if you saw a sign that said \"No swimming allowed after 10 PM\" by a pool, you are given the exception (no swimming at that time) from which you can infer the rule (swimming is allowed) and that it's valid in all other cases (swimming at all other times).",
"It actually comes from the English (and languages before that) that also means “to test”, i.e. a Proof House for weapons. It does not mean that an exception means the rule is correct. URL_0",
"I think of it like this: if there is no rule, then there is no point to exceptions either. If an exception exists for the minority of instances, so must a rule exist for the majority of instances. So, basically what others are saying, but using different words in different order."
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o0l5ho | What happens to your body physically when you get struck by lightning? | Other | explainlikeimfive | {
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"Lightning is electrical energy and electrical energy 1) wants to head to \"ground\", usually, literally, the ground and 2) generates heat as it moves through things. So depending on where you get struck, the lightning is going to travel from the strike to the ground. So if it hits your knee, it'll go straight down to the ground. If it hits your left arm, and doing a cartwheel, it'll travel across your chest into your right arm and into the ground. it terms of damage to the body it'll A) cause burns because of the heat, those can be pretty nasty and B) cause electrical damage to your nervous system. A relatively weak electrical charge can stop your heart mid-beat so if the lightning crosses your chest that's usually bad news."
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o0l96q | Does female orgasm play any role in fertilization? | Biology | explainlikeimfive | {
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"Yes, in the sense that reaching an orgasm is an inherently pleasurable experience, and so people are likely to try and do it again. A woman is fertile a few days per cycle, so having sex one time completely at random is unlikely to get her pregnant; by encouraging her to repeatedly have sex, the orgasm greatly increases the chance that she will actually have a child, which will almost certainly inherit the genes for experiencing orgasms.",
"The “upsuck hypothesis” proposes that the contractions associated with female orgasm can draw sperm closer to the uterus and lead to higher sperm retention and increase the likelihood of fertilization. There is some data to support this hypothesis but it has not been broadly studied.",
"Not that we know, at least not in humans. There might be some sexual and social selection events where female orgasm plays a role, but I can't remember any hypothesis that has been demonstrated with hard science, all there is are claims that pleasure may contribute to females wanting to engage in intercourse, but observation in other animals species (even most mammals) proves that's not necessarily the case. It seems to be relevant for human culture, but not necessarily in fertilization from an evolutionary point of view. In vertebrates in general, female orgasm may exist because male orgasm exists, the structures that allow for male orgasm are also present in females because sexual differenciation consolidates quite late during embryological development (in anatomical terms). With \"late\" I mean, not during the first weeks. So females possess many of the same anatomical structures as males, but in a more vestigial form, and the same is true for males, they possess many female anatomical structures in vestigial form (like nipples), and they don't play any role that is relevant for natural selection. They belong to the same species after all, so there will always be some overlap with sexual specific structures and physiology."
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o0mj65 | Why does hitting the TV remote make it work? | Technology | explainlikeimfive | {
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"The only way this would happen is if the batteries are not seated properly. The rest of the remote has no moving parts, hitting it should do nothing.",
"Rust/Dirt on the battery contacts or not properly seated batteries can both be solved by a physical jolt. But either way you're better of removing the batteries and reinserting them a few times"
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o0nga4 | What actually is that slimey vaginal discharge that women get? | I get it everyday and when i asked this to women around me, they just say it's normal wihout explaining what it actually is and what causes it. | Biology | explainlikeimfive | {
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"Mucus. Vagina is covered by mucous membrane like mouth, the inside of nostrils etc. Mucous membranes are covered by a layer of mucus that enables their function (keeps the right ph balance, right micro biome, and because it has no layer of dead epidermis it protects it from drying out). In vaginas it also serves to flush out foreign bodies like bacteria that can cause infections. In case of infections that develop discharge can increase, change in texture, smell or colour because it contains other things like dead antibodies etc",
"The discharge women get most of the time is a mix of cervical fluid (a mucus) and water. It keeps the vagina clean by flushing out bacteria. Over the course of a woman’s menstrual cycle, the amount of cervical fluid can fluctuate. Before and after a woman gets her period, discharge is usually more watery. Around the time of ovulation, however, the discharge has more cervical mucus and gets thicker and “stretchier.” This is because, in addition to keeping the vagina clean, discharge actually helps a woman get pregnant. During ovulation, stretchy mucus makes it easier for sperm to get to the opening of the cervix so that they have a better chance of finding and fertilizing the egg. Finally, a woman can also secrete *transudate* (a thin, slippery vaginal lubricant), particularly during periods of physical arousal. This makes sexual penetration easier and more enjoyable.",
"It's a fluid (also called mucus) that comes from the vagina. Its purpose is to keep the vagina moist and clean, it also protects from and fights against infections. There is more information on health websites, like the NHS or even kids health.",
"So cool thing about vaginal discharge. It basically acts as a \"mood ring\" to let us know what is going on down there. Changes in colour, smell and consistency of discharge tells you a whole lot about what's happening down there. Examples: Thick, white, cottage-cheese texture discharge with no smell generally indicates you have vaginal thrush. Usually also accompanied by itching or burning feelings down there. Fishy or generally bad smell can indicate possible infections. Same with green or yellow discharge. Best have it checked out. What we eat can also affect the smell (maybe taste?) of our discharge as well. Stuff like asparagus and pineapple can change the smell and taste (?) of our discharge. (source: a nurse i spoke to growing up. Would appreciate if anyone else has a better source, i may be wrong).smoking, alcohol and drug use can also affect taste (?), smell and quantity of discharge. As the above commenters said, discharge consistency changes depending on our cycle as well. And depending in the pH of our discharge can \"bleach\" our underwear- it happens. If you are at all concerned about your discharge or have questions for whatever reason, have a chat to your local pharmacist or doctor. Don't stress yourself out. We've heard it all and are here to help. Source: pharmacy intern."
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o0nzl1 | Will siblings get the same results in DNA kits like URL_0 ? | Biology | explainlikeimfive | {
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"Theoretically yes, but alot of those DNA tests are based on sketchy science. A couple investigators tried out the DNA tests using twins and triplets and got widely different results for each of them despite having exactly the same DNA. It's a question of how the genetic results are interpreted, and there's a reasonable chance that several of these companies just straight up fabricate the results while selling what information they discover to other parties.",
"It depends. Let's first talk about genetic markers. Certain genes are common to certain areas. (think red hair and Ireland). You can use these gene markers that are in your DNA to link back that you have relatives from those areas and that's where you got it from. Sometimes these genetic markers aren't always a physical characteristic or so easy to see. Some of these markers are also not 100% accurate. Most of these companies build up their DNA databases using standards of people generally from that area to compare against. This means that not ALL of the markers are truly reliable. This is generally why most of these genetic tests should be taken with a grain of salt. They are good to get a general idea, but they are far from being very accurate. Now, if you and your brother are identical twins, you should receive the exact same result from the same company. If you're fraternal twins, just skip to as if you were brother/sister) This is because your DNA is identical. If you did two different companies (say 23andMe and Ancestry) you would likely get *different* results because the genetic markers that they use are different and their databases are different. Not to mention none of this is really an EXACT science that we're \"100%\" sure these markers come from a specific place. Some are really good and others not so much. Now, if your sister did it, even with the same company you have a decent possibility of getting slightly different results. Its highly unlikely that you'd get drastically different results, but you might see percentages change a bit or perhaps other regions might have a 5% of something else. While your DNA is very close to what your sisters is, it's not exactly the same. Depending on the markers that each company uses as well as their database. EDIT: the biggest factor in having your results be the same/different would be the company you check your DNA on. If YOU were to check your DNA again with another company, you could very easily see different results.",
"Imagine you are mixing up a recipe. Half of the ingredients come from your dad and the rest of the ingredients come from your mom. The issue is this: even with siblings, your ingredients won't mix the same as your sisters. Like soup, you may end up with a bit more carrots while she has more celery. But, in the end, you can tell it's from the same pot of soup. That's the way it is with heritage. You may pick up a bit more French while another sibling picks up a bit more English. It's the roll of the dice...which exact DNA strands you pick up. The biggest issue is when you expect chicken noodle soup and get a steaming bowl of Menudo. That means mom has some explaining to do."
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o0o8sw | Why do men tend to have erections in the morning ? | Biology | explainlikeimfive | {
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"Penis tissue needs regular blood flow to stay healthy so every healthy guy will get an erection every so many hours to keep blood flowing into the tissue. This commonly happens over night when your body is doing a lot of its \"maintenance\" to keep you healthy."
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o0ohop | How does carbon dating work? | In some other post I've seen that there was a spear found on the bottom of the sea and scientists managed to carbon date it 16000 years back. How can we tell that this is the time when spear was made or submerged? What makes the spear different than the material it was made of? Thanks Edit: typos | Physics | explainlikeimfive | {
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"So most things have Carbon-14 in it. This is a form of carbon that is radioactive, and will decay over time. However, the time it takes for half of it to decay is very long. Because of this, we can measure the activity (measured in counts of radioactivity per minute, or Becquerels) and figure this out as a proportion to its half life. So if it has a half life of say, 10000 years and its activity is at 75%, we can tell it was from 5000 years ago as it is halfway through its first half life.",
"A relevant part that the other posts have missed is that Carbon-14 is continually produced in the earth's atmosphere. Some omic radiation that hit Nitrogen-14 turns it into Carbon-14. So there is a quite constant level of radioactive Carbon-14 in the atmosphere because of the production. So you can date something because the percentage of Carbon-14 when the plant grew was constant. & #x200B; There is some fluctuation of carbon-14 levels and human nuclear testing increased the amount so there was almost double the normal amount in 1963. Today it is at around 10% over normal. So in the future, there will be problems dating stuff that grew recently."
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o0osqt | Does human body have analogues to electric circuit components? (capacitors, transistors, etc.) | Biology | explainlikeimfive | {
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"Yes. But they work within cells or across a few cells rather than the human body acting as a a giant electric circuit. Neurons are cells that use electricity to communicate from end of the neuron to the other. But neurons do not use electricity to communicate across neurons - they use chemicals for that. So while your brain is often portrayed as running on electricity running around your neurons, it is actually electricity running through a neuron, a chemical message to the next neuron, then electricity running through the next neuron. You do not have electric current running through your brain.",
"It may do, we don't really know. There seems to be a lot more to nerve cells than we first thought, but we don't know exactly what that more stuff is yet. To explain this I'm going to explain the entirety of how nerve cells work, not just which specific cells exist, because I think it's interesting and because it may give some insight into how humans differ from computers. First, the cell establishes a difference in electrical charge inside and outside the cell, by pumping positive ions outside it. This creates something called the \"resting potential\", which is typically at around -70mV iirc. That is, the inside of the cell is 70mV less positively charged than the outside. Don't ask me why it's measured in volts cos I have no clue, it just is. The membrane of nerve cells contain things called voltage-gated ion channels. when these channels open, ions flow through them down the charge gradient. This results in the inside of the cell becoming more positively charged: the electrical potential reduces in a process called depolarisation, to the point where the inside of the cell is about 30mV more positive than the outside: +30mV. The \"voltage-gated\" part of this means that these channels only open when the potential falls to about -55mV. As you may have figured out by now, this means that if the charge of the cell increases to -55mV, for any reason, the channels will open, increasing the charge to +30mV - which is high enough for the next voltage-gated ion channels in the cell to open. Since nerve cells are long and thin, this causes a rapid wave of depolarisation all the way down the cell. Once this has finished, the cell sets to work re-establishing that original resting potential, so that it can fire again later. The end of the cell has a slightly different structure. When the depolarisation reaches the end, the end of the cell (called the pre-synaptic membrane) releases a kind of chemical called a neurotransmitter into the water-filled space that exists between two nerve cells, called the synapse. This is where nerve cells get interesting. There are proteins in the surface of the next nerve cell (the post-synaptic membrane) that can stick to these neurotransmitters. When they do, they open up, causing a small amount of positive ions to flow into the start of the next nerve cell. This raises the internal voltage slightly. If the voltage can raise to -55mV, then wuh-hey, that's a new wave of depolarisation in the next nerve cell, and the message is continued! The start of most nerve cells takes input from a lot of other nerve cells. This means the nerve is kind of unconsciously doing addition. Multiple cells will be giving it a small number of positive or negative ions which will increase or decrease the internal charge accordingly. If the sum total of all these different sources causes the internal charge to be -55mV or higher, the cell will fire. If it doesn't, then all the incoming messages end there. So, nerve cells don't just propagate messages, they can also determine whether or not they *should* fire based on inputs. Computers can use a bunch of and, xors and or gates to do addition that outputs a complex binary number. The nervous system can do pretty complex addition in just one cell. Now, I know basically nothing about how computers work but I'm pretty sure this means the brain is basically running a system with more options than binary and I'm pretty sure that's what makes quantum computers so fancy. Now you have a basic understanding of what a nerve cell does and what causes it to do it, I can describe a few of the types of nerve. Nerve cells fall into three basic categories: Sensory neurones, relay neurones and motor neurones. Sensory neurones initiate messages upon some spontaneous change in themselves. Relay neurones receive incoming messages and send them to other nerves, and motor neurones receive incoming signals and instruct a muscle to do something as appropriate. Now we know what these do we can start building some \"circuits\". Let's start with a really, really simple one. You're a small immobile animal living on the sea floor. You have a shell which you can withdraw into, and you only need to contract one muscle to do it. The only reason you would need to do it is if you think there's a shark above you. So, you evolve two neurones: A light receptor neurone that sends a message when it detects a reduction in light level of X or more, and a motor neurone that causes that muscle to contract when it receives a message. This is simple: When the light receptor fires, the muscle contracts. Was there a shark? You don't know, you don't need to know, but if there was you're protected now. But you're not a small immobile animal living on the sea floor. You're a small immobile animal living on the sea floor *who reproduces sexually*. That means if you want to have kids, you need to make sure your potential mates can access your egg tube. As it happens, the males of your species are really big and can swim. This means when one swims above you, it causes a reduction in light just like a shark, and if it were to swim above you your simple nervous system will cause you to withdraw, blocking access to your egg tube. So you need a way to be able to distinguish between sharks and males. Fortunately, males of your species emit a pheromone - a specific chemical. You have a second sensory neurone that detects this chemical and sends its own message when it does. You also add in a relay neurone, which both this nose and eye connect to. The nose neurone floods the relay neurone with negative ions when it sends its signal, which will make it less likely to fire itself. This means when the nose neurone detects the pheromone, it can send what is effectively a \"don't contract\" signal which overrides the \"contract cos there's a shark\" signal by preventing the relay neurone reaching -55mV. As such, you still contract when shadows happen, unless those shadows smell like men. This illustrates the role of relay neurones: they can give multiple different outputs by taking into consideration multiple different inputs. Really complex nervous systems like those of humans are just the result of having a whole fuck ton of different sensory, motor and relay neurones so the system can take into consideration loads of different things when determining whether or not to take an action."
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o0p68c | how do soldiers who have to stand still for so long never cough or sneeze? | Other | explainlikeimfive | {
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"They definitely still cough or sneeze. And you aren't really expected to keep your composure e.g. refrain from covering your mouth/nose; you just cover your mouth/nose appropriately and then return to position. Besides, almost every time that you are standing in formation for an extended period of time, the formation leader will put the formation \"at ease\" which allows for some minor relaxed movement. But seriously, even if you're at attention, no-one is going to rip you for breaking composure to cover your mouth.",
"As a retired Soldier, you cough and sneeze the trick is to do it when the eyes arent on you. But yes years of formations have taught me how to hold it in"
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o0q4j8 | why do billionaires exist? | Economics | explainlikeimfive | {
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"You start a company. The company does something new and novel better than any other company. Or, you ruthlessly crush competition. Very quickly, you own 20% of a stock-market traded company that gets valued as being worth $20 billion. You can’t give that all to charity, or you lose control of your company. You aren’t ready to turn it over to new CEOs. So, you are worth $4 billion without doing anything more than any other ambitious business person. You really can’t start giving that money away until you are ready to quit the company."
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o0qjwg | Aftermath of Medieval wolf hunts | What did they do with the wolves once they were dead (for time period, maybe between 1200 and 1400?). Did they just leave them lying in the forest or wherever the hunt took place? Did they burn them? Did they skin them and sell/wear the pelts (I read somewhere that this was unlikely)? Did they eat the meat? | Other | explainlikeimfive | {
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"Some probably took souvenirs - pelts, paws, heads, tails, doubtful that many were eaten, most probably left to rot. Some probably burnt."
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o0qy6p | What is anti-aliasing? | What does it do and how does it work? | Technology | explainlikeimfive | {
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"If you look really closely at a screen rendering 3d graphics, any lines not at vertical or horizontal angles will tend to look \"jagged\" and like stair-steps rather than a smooth surface. It's especially noticeable if you lower the render resolution way down. This effect is known as aliasing. Anti-aliasing is a way for the computer to interpret this meeting of two different shapes, and average the pixels in the stair-steps to smooth out the image. I used to play with making a similar effect in MS Paint: make an angled black line on a white background, and then out from each black pixel into the white, make successively lighter shades of gray. When you zoom out, it will look a lot nicer than the abrupt change from one color to the next. Photoshop/other full-featured editing programs also do this automatically when you choose a brush with soft edges. Hope all this helps. :)",
"When there is a diagonal line in an image it fades the edge so it’s harder to see the jagged edge of the pixels. It can make lower resolution screens less noticeable.",
"anti-aliasing is basically blending out pixels that make a line, to make the line they're part of appear smoother from further away. here's a good pic of what it looks like both from far away and zoomed in: URL_0"
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o0rvdc | why was the spice trade so important if European food isn’t spicy | Economics | explainlikeimfive | {
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"Cinnamon, ginger, nutmeg, clove. These are spices but are not \"spicy\" in the way you are thinking. The spice trade wasn't just hot peppers.",
"There are tons of spices that aren’t spicy — things like peppercorns, cinnamon, cumin, cloves, coriander seed, etc. and they were of even greater importance back in the day as a means of masking rancid/bad food that nonetheless had to be consumed due to lack of fresher food"
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o0sllv | How exactly does a bee hive work, and how does the honey production cycle work? | Biology | explainlikeimfive | {
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"Bees live in a beehive, mostly workers and one queen. The queen lays eggs in honeycomb cells in the center of the hive. The outer areas are filled with pollen, nectar, and honey. Pollen and nectar are collected by the worker bees from flowers. Honey is created when a worker drinks honey in a second stomach and starts digesting it. They they spit the honey into a honeycomb cell and fan it so that the water starts evaporating. Once enough water has evaporated, they cap the cell to store it for later. This is what gets collected by beekeepers to process and sell.",
"Beekeeper checking in - queens are produced from the same egg as workers. The egg selected to be a future queen is fed more royal jelly which changes her physiology when she is developing. Once born, she will battle any other queens to the death. She then matures for about a week, then flies off for mating. She typically mates with 15-25 drones. After returning to the hive she will start laying eggs within a week or so. At here peak she will lay approx 1,500 eggs per day. Workers are all female, but do not typically lay eggs. They have different types of roles in the hive based on age. In rare instances they will lay eggs, but since they never mated, the eggs are all male. Drones are males with no father, but a grandfather. They do no work to improve the hive. Their only function is to spread the genetics of the hive. They are driven put of the hive in the late fall since they have no value at that point. Honey is nectar that is collected, concentrated and processed with enzymes. A forager bee brings the honey into the hive and passes it to another worker. They then store it into a comb. During this time enzymes in the bee start processing the honey. Once stored the comb is left open until the concentration of water drops to around 17% and then it is capped. Workers live about 6 weeks, unless it is winter and they can live up to 4 months in the hive. Queens live 2-4 years assuming they are not killed by another queen."
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o0sudt | How does hypnotherapy actually work (does it actually work at all?) | I’m assuming here what we see on TV - someone going under and remembering a traumatic repressed memory with vivid clarity - is oversimplified, if not completely inaccurate, but I’m a dummy about this so I’m just wildly guessing. Does anything specific actually happen in your brain or is it just one of those things that has varying results for different people/is dependent on suggestibility (not that there’s anything wrong with that, I feel like I’m probably highly suggestible as a person)? | Other | explainlikeimfive | {
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"According to the linked source up to 28 percent of subject's hypnosis memories were verfiably false. URL_0",
"The goal of hypnosis is to enter a relaxed mental state. The veracity of the practice is up for debate, and results largely depend on the willingness of the subject. In a sense it's like a placebo effect; willingness is integral to success. Does a subject's brain activity change under hypnosis? Sure; it also changes when angry, sleepy, etc. So-called \"real\" hypnosis is very much akin to guided meditation, which also seeks to quiet the conscious mind so the subconscious takes center stage. Like the other guy said, the accuracy of recovered memories is suspect, but that's true for any memory. Same reason eyewitness testimony is so often wrong. A burgundy sedan becomes a red coup, a goatee becomes a full beard, etc."
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o0swk7 | how do local anesthetics such as novocaine work? | Chemistry | explainlikeimfive | {
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"all local anaesthetics are stabilizing membranes by reversibly blocking na ion channels. by saying stabilizing membrane i mean they decrease the rate of depolarisation of excitable membranes, when the membrane can’t depolarise, an action potential can’t arise and the signal conduction is inhibited. that means it can’t send the signals of pain, touch, temperature, proprioception and motor. so basically local anaesthetics are blocking the nerve cells to block their actions."
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o0sy0k | How does turning off your computer with the physical power button cause file system damage? | I was always told never to turn off my computer (or even gaming consoles) with the power button because it can mess up the file system. But I never understood how it happens, or why it happens. Do you think computer technology will ever advance past this obstacle? | Technology | explainlikeimfive | {
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"Files systems are slow. Your computer and game console will sometimes keep data cached in RAM and commit it to the file system at a later time. If you turn off the power before the data is written to the file system then it could result in data corruption.",
"Imagine it like this -- you're at work, filling out and filing your monthly reports. Someone asking you to come by their office after you're done is like shutting down through the OS. You have whatever time you need to complete your reports. Someone forcing you to stop now and come with them is like the power button. Now you have a bunch of reports that aren't fully filled out, or done properly. Except with a computer the reports are files, and unlike our office scenario you can't just come back to them later because RAM is volatile and needs continual power to not forget everything.",
"Basically, writing files to disk takes time. Significantly more time than writing something to memory. So your system is setup to write things to memory quickly, and then to disk eventually. If you hard-stop the system, then it is possible that there was a file in memory that never was written to disk. That means you could lose data. Worse yet, you could have two files that are supposed to be updated in tandem, and one could have been written to disk, but not the other one. This creates an inconsistent state between the two files -- whoever wrote the program may not necessarily have thought of this situation, or even if they did, there might not be a good way to recover. Worse yet, these don't necessarily need to be some text or config files. They could be actual executable code that is being updated. That is really hard to work around, and will basically always require some sort of repair job. Worse yet, it could be the windows update code itself that handles bad system files. There's no backup for that! If that gets corrupted in an update, you definitely need to do an external OS repair to fix it!",
"Computers have a series of tasks that they are completing in their normal operation. One of the major issues is that in order to work quickly with files they are copied from relatively slow long-term storage into \"memory\", an extremely fast form of data storage that has the downside of being unable to hold its data without constant power being available. Normally a computer will copy the files it needs to use into active memory and modify them there as it goes, until at some point they are written back to the long term storage. The physical power button on your computer will, if held down for a period of time, simply cut power to the computer immediately. Any data that is held only in memory will be lost, and if the computer is currently overwriting a file that it modified then it would stop in the middle resulting in a corrupted file. Computers are *extremely* complex and the file that will be corrupted isn't necessarily just your Word document or whatever, it might be a file that is very important to the operating system itself. One process the computer does for example is when writing a file to storage it will keep an index of where the file is stored, which is often split between several different locations. Being interrupted while modifying this index can be bad news even for unrelated files. There are various ways to \"advance past this obstacle\", the most straightforward way being to simply remove the user's ability to actually cut power to the system directly. You see this on phones and tablets where the power button simply requests the device shut down gracefully; the user isn't given the freedom to directly cut power because they aren't considered competent enough to use it wisely.",
"Imagine a doctor falling asleep, in the middle of performing surgery. This is essentially want is happe jng if your computer looses power in the middle of an update or other major action. Shutdown properly allows for it to make sure every can shutdown gracefully and not risk corrupting anything."
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o0twsd | how do those water dispensers heat and cool water so quickly? | Like those water dispensers that have the hot and cold water. How does the hot one produce near boiling water and the cold one really cold water directly after one another? | Other | explainlikeimfive | {
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"There is a small holding reservoir for each side, that is heated or chilled. It is not an infinite supply, and you will eventually run out after filling multiple water bottles, and would eventually get room temperature water.",
"Because they do it in very small amounts at a time, with maximized surface area exposure. When you think about the flow rate of these devices, you are usually considering a very small amount of water being dispensed at a time. By spreading out the area of contact between the water and a refrigerated coil (or a resistance heating element), temperature change of the fluid can be very swift.",
"I am so happy I visited this subreddit, I have had this thought about the BOILING hot water that comes out of the dispenser at my job."
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o0uj5l | Why do mosquitoes fly around a bunch, then just stop and wait? Same with flies! What are they doing? | Biology | explainlikeimfive | {
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"Don't you think that's a lot like asking 'why aren't birds constantly flying'?",
"They're waiting for you to have both your hands full / occupied with something. Picking the right time to strike. You can't swat at them while holding grandma's casserole dish.",
"Well they also look for something to eat, and if there's another potential sexual partner around, they look for that too in order to reproduce. In the case of females, they'd be looking for a place to deposit their eggs too. But they generally don't do much. They are not very complex in terms of behavior, so they just do the basic functions of any living animal: the look for food, to reproduce, and some safety.",
"mosquitoes are also one of the slowest flying flies. they fly at most 1.5 miles an hour…. so if they look like they’re just “floating”, they kinda are…. super slow guys."
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o0v5l3 | how is lysergic acid diethylamide (LSD) manufactured? | Chemistry | explainlikeimfive | {
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"text": [
"An ELI5 of LSD is an oxymoron. It’s a difficult, sensitive synthesis. You can find details on Erowid",
"get a bunch of rye, get the rye to grow ergot fungus. Use a bunch of very dangerous chemicals to extract a specific chemical from the ergot. Use some more chemicals to change that chemical into LSD. Most of this process has to be done in a dark room."
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o0vlgi | how does Live Photo starts few secs before I snap photo | So the Live Photo records few seconds before you snap. But how does the phone know I’m going to snap the photo in few sec? Does that mean my camera is always filming me? | Technology | explainlikeimfive | {
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"text": [
"It is sort of recording all the time, and then immediately discards frames as soon as 1.5 seconds have gone by. It's only 15 fps (frames per second) instead of 60 fps like if you recorded a video, so it's not very intensive to hold this data for a short time and then to discard it.",
"The feed from a modern camera is always running, and continuously running filters / facial recognition to find faces etc (that's what makes smartphone photos look way better than what it's lens/sensor can do physically), so it's more like it normally discard the footage after a few seconds unless you take the photo, that's when it writes in-memory footage into somewhere more permanent",
"There's no way for it to \"know you'll take a pic soon\", so yes when that mode is on, it's constantly recording and temp-saving just the most recent few seconds (like how a closed circuit security cam works, always recording the last few hours and constantly taping over the oldest footage). When you snap the pic it saves the most recent few seconds permanently."
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o0wbkv | what it means when assets are liquid and why that can be either good or bad | Economics | explainlikeimfive | {
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"Liquid assets are either cash or something that can be turned into cash very quickly while retaining their value. They are good, because if you need money, you can turn your asset into money very quickly and spend it. No risk of losing money in the conversion. Think, cash, money in the bank, some types of investments (stocks, bonds, mutual funds). Things that aren't liquid: real estate, some types on investments, car, boats, planes, jewelry, etc. You want to have some liquid investments, because if you lose your job, you want to be able to sell them to pay your rent and buy food.",
"Liquidity essentially boils down to “how fast can I convert this into cash without it losing value.” Something like a factory or building is not very liquid because if you needed to “liquidate” it, it takes time, effort, and money to receive it’s full worth in cash. Because of this, fast liquidation of these non-liquid assets usually means losing value. The benefit of high liquidity is that you can quickly get cash out of it and use that cash in various financial projects. However, high liquid assets usually don’t provide the same returns as long term assets. A factory might be hard to liquidate, but it can yield a lot of money. There is a happy medium of having liquid assets and cash to carry out the day to day operations, and also having long term assets which usually yield a higher rate of return.",
"Liquidity is a measure of how easy it is to sell or trade an asset. Cash as an example is a very liquid asset because its very easy to trade with. If you want something and all you have is cash, then you are in luck. Just buy it. A house on the other hand is not a very liquid. If you have a million dollar house, you technically have a million dollars in assets. You just wont be able to actually spend that million dollars until you find a way to liquidate that housing asset.",
"Cash solves problems. The more literal the cash, the better and faster it solves the problems. \"Liquidity\" is how much cash you can access within a given time period. For home finances, this is usually what you can pull together within a couple of days. The most \"liquid\" cash is a sack of money under your mattress. Less liquid would be a savings bond or Certificate of Deposit that you can technically cash out early with, but with big penalties. Stuff that takes weeks to actually sell to the point that you have literal cash in your pocket would be Cars, Houses, and the like. Cash & Liquidity are good because it means you can make a move NOW given the opportunity. Or you can just use that cash to solve the problem of not having a job so you can cover rent & food for a couple of months. Cash is bad because a sack of money under your bed only solves problems as a reaction. It doesn't make you any money and never grows as an investment. That's why being \"too liquid\" is bad. You can make any move in the world, but if you don't make one, you're making just as much wealth as the poor kids down the street. So it's best to maintain a balance. In home finance, it's usually advisable to keep 6 months of cash savings as liquid assets. That's usually enough time to float one curveball from life and figure out a new normal. Once you have 6 months of cash stuffed under the bed, it's best to start investing your money elsewhere. Sure it's not liquid (because you can't cash it out quickly), but you can cash it out eventually with more than you started with. Probably."
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o0xfhf | - Why is space black? If their is so much light every where? | Any thoughts? | Physics | explainlikeimfive | {
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"Much of the light we are \"supposed to see\" is coming from the early days of the Universe, when it became transparent to photons. Because of the expansion of space, the energy of these photons has been redshifted to microwave wavelengths. This is what we call the cosmic microwave background radiation and we simply can't see it with our naked eyes. If you look at the sky with a camera sensible to this radiation, the sky is definitely not as dark!",
"Space is big. Really big. You just won't believe how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space.” Thanks to the inverse square law, light sources decrease in intensity with the square of the distance, they get fainter faster as you get further away. Within a few hundred light years, even the brightest stars are only a small smattering of photons to an observer."
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