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7a8z27 | Why do girls menstrual cycles sync up when they live in close proximity to one another? | Biology | explainlikeimfive | {
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"They don’t. It’s been studied and the idea that they do is a combination of confirmation bias and misunderstanding of probability.",
"The latest research shows that syncing doesn't happen. What people perceive is observation bias. Also factors include bad records, varied definition of when a menstrual cycle begins, and bad scentific methods."
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7a9e3h | Why does semen “ball up” and get hard when introduced to water? | Biology | explainlikeimfive | {
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"Semen contains a lot of protein. Proteins are rally long molecules made of amino acids (mostly Carbon, Hydrogen, some Nitrogen and Oxygen). In their \"normal\" state they are nice long strings, but under the right (wrong) conditions they tangle up like the headphones in your pockets and become a weird ball. Same happens when you cook an egg. Cold water is your friend when cleaning up.",
"For a full explanation and link to af fun video, see [here]( URL_0 ). In short, semen has 2 important proteins: one that binds it and one that dissolves it. Together, they keep your sperm together to help make the perilous journey through the vagina. The current theory is that water interferes with the dissolving protein. With nothing to counteract the binding protein, semen hardens/becomes more solid. This is actually pretty similar but also the opposite of glue, which contains water. Glue is like the binding protein and water in the glue is like the dissolving protein. When you take glue out of the bottle, the water starts evaporating and the remaining glue can start being sticky. Edit: fixed link"
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7a9o7m | How does someone build up a tolerance to alcohol? | Biology | explainlikeimfive | {
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"There are proteins in your body called enzymes. There are many enzymes in your body that breakdown drugs so your body can get rid of them. When you ingest more of a certain chemical over a period of time, your body makes more of the enzymes that are used to break them down. Since the chemical is being broken down more quickly, you need more of the compound to get the same effect.",
"Couple of reasons why. Tolerance is mostly physical, slightly psychological. The psychological part is where you know how drunk you are and how much of yourself you're able to keep in check. The physical part, has to do with your brain and your liver. Alcohol, behaves similar to a neurotransmitter called GABA in the brain. GABA works to tell neurons to 'sleep' or stop transmitting, and the effects of alcohol are explained by more parts of the brain turning off or functioning differently. When the brain is exposed to alcohol for some time, it changes the number of neurotransmitter receptor sites, and increases the transmission of other neurotransmitters like glutamate, that help keep you awake. This means it takes more alcohol to make you as drunk as before, because your body is compensating for the impairment. The liver also makes changes by increasing the amount of machinery needed to process all the alcohol. That's what causes the liver to enlarge in people who drink for a long time. This means that the liver is able to process more alcohol faster, which is why you can handle your liquor much better than lightweights who barely drink; your liver is used to handling the load. Tolerance depends on how much and how often you drink. It also varies slightly based on your genetic make up, gender and ethnicity. Some east-asians have lesser enzymes to clear alcohol, so they get drunk really fast. Women also tend to get drunk faster because their body frame is smaller and they also have lesser enzymes for metabolizing alcohol compared to men."
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7a9pr1 | Why are video game graphics just now becoming so detailed and in depth? 10 years ago, you couldnt see reflections or walk up stairs properly, but now you can? What has happened to code writing that's allowed this? | Technology | explainlikeimfive | {
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"It’s not code really. It’s waaaay more powerful processing being widely available. Both CPUs and GPUs. All of those details take a ton of processing power to do, processing power that 10 years ago wasn’t so readily available.",
"In some cases it can be coding, with programmers learning to do new things, but the big thing would be processing power. 10 years ago, the average consumer computer was much weaker than it is today. The computers could only do so much at once, while maintaining a reasonable framerate to make the game playable. A really good example is the movie Toy Story. Looking back at it, by today's standards, it is pretty basic, but at the time in 1995, it was cutting edge. To add to how hard it was to make, each **frame** took 45 minutes to **30 hours** to render. And this was done at 24 fps at 1536x922 resolution. And even then, it took about 300 processors to render all of that. At the time, that was pretty impressive for a film that could probably be rendered in real time with a modern day machine.",
"Computers got more powerful. It isn't the code. We take for granted the sheer amount of computation needed to render stuff in games. Just take a look around you in the room you are in, you are probably in the presence of a light bulb or the sun. This is a bit more fun to think about with a light bulb, but just take a look around you, at all the shadows, how everything is lit up, the reflections, ect. Light radiates out predictably in a straight line and this makes our calculations possible. The computer has to calculate all that, it has to calculate if there is line of sight between an object and a light source to see if a shadow is applied to behind it, it has to calculate how that shadow will look like based on blocking it. You can do all this by hand theoretically, it is just algebra and trigonometry, but you would likely die before you finished all the calculations needed just for one second. Colors as a result of lighting as well, and even the player's line of sight has to be calculated. And it is all done at the very least 30 times per second. All done on a rock that we tricked into doing calculations."
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7a9rqj | Does getting hit on the head have to do with losing your taste buds? | Other | explainlikeimfive | {
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"Your tongue has many taste buds which send small signals to your brain whenever it tastes different things. When you hit your head just right, you can make it hard for those taste buds to communicate effectively. This can mean you lose one of your senses. Personally, I'd hate to never be able to taste chocolate again!"
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7a9s00 | What is Price to Earning Ratio | Economics | explainlikeimfive | {
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"Exactly what it sounds like\" The price of a companies stock, divided by their earnings per share. The idea is it's supposed to let you compare how expensive a stock is. If i want to buy a stock for $200, is it cheap, or expensive? There's no way to know without more context. You could have a $200 stock that is raking in tons of earnings (or is expected to in the future), or a $200 stock that is doing pretty \"meh\". You can think of it as \"how much does it cost to get $1 worth of the companies' earnings?\" The average P/E is ~20-25."
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7a9vlh | How did we arrive at a 40 hour work week? | Other | explainlikeimfive | {
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"Through constant struggles between workers (through unions) and employers, which currently sets it at a compromise at 40 hours. There is a pretty strong movement to reduce it further, usually 30, 32 or 35 hours, but we are not there quite yet. I suspect it will happen. Increasing automation means that we will have to decide between: * less time worked per person; * mass unemployment; * people doing \"fake\" or \"constructed\" jobs of little real value. Of those alternatives, less time seems the best.",
"Here's something I remember from my grandparents, who were involved with the unions in the 1930s - my grandmother was involved in the Textile Strike of 1934 and my grandfather was a member of the IWW and their attempts to organize railroad workers (he worked for the Southern Railway at the time). They both had a saying: \"Eight hours of work, eight hours of sleep, and eight hours of what we will.\" So five days of work at eight hours equals 40 hours. That was their goal. I believe this saying originated in England and was brought home by American soldiers who had served overseas alongside British troops. So that's my understanding of the \"40-hour\" week.",
"The short answer is: Blood, violence and death. In the fully developed industrialsation, around the end of the 19th century up until the early 20th, workers had very little rights. You worked 12 or more hour shifts, you got paid by results (kg of coal found - you only struck rock today? Well, bad luck for you!). They were basically (ELI5) modern slaves, the employer could set rules, remove pay, they had no insurance for illness or retirement. They lived in very small flats, and beds (!) often were rented out to strangers - you do do not need a bed when you are working, right? If you annoyed your employer, you lost a job in a time without any social welfare and no way to safe up money. If you had an accident at work, you might have been brought to the hospital ward, which was conveniently outside of the factory area which means that if you die after your (work) accident it happens outside of the factory/mine and this means your family cannot get pay. After all, you did not die at work, right? (The list goes on and on) Then people got fed up with it and went on strike. Often that was to the dislike of the state which send the police and the factory owners who sent strike breakers (workers and muscle for punching). This went on and on, workers formed Unions to fight back and over time the violence led to peaceful strikes which leads to the systems, workers' rights, social security and welfare you have today. Even the whole environment-debate is part of this, as by now we decided that the health of a countryside is more important than the profit of the factory-owners. In some countries all that is better developed than in others. --- Now, why we do have to work more than in past times (40 hours a week) is a whole different matter. I doubt Neanderthals worked more than some 30 (or something rather low) hours *per month* for getting food and firewood. The pay and recreation options were probably just cheaper. ;) [And since so many \"nice\" people asked so \"nicely\", here is some link [Wikipedia]( URL_0 ) but because they were such \"nice\" people I am not willing to do more research for such \"nice\" people.",
"8 hours to sleep, 8 hours for yourself, 8 hours to work. 5 days a week. Weekends cuz God. 40 hours",
"Interesting read. In my country, Denmark, it's 37 hours a week. Some political parties are fighting to lower it because of stress and family life and because we get paid enough to lower it, it's not unrealistic.",
"Not sure if this is allowed, but this link I found explains how auto workers first went on strike to demand a work week that wasn't as harsh for the workers, attempting to scale back from a 48 hour week to a 40 hour week, several other strikes followed, along with a terrible fire at a shirt factory that led to the Fair Labor Standards Act that established the 40 work week as the standard. Let try that link: URL_0",
"A lot of things went into it. workers were pushing for better conditions, unions started forming, people died from shitty work conditions, and then [Henry Ford set the 40 hr work week in place]( URL_0 ). Ford was one of the biggest companies then so that was a big deal. Then in the 30s, the fair labor standards act was passed and I think thats what standardized the 40 hr work week"
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7aa45g | what is a strong and weak type of language in programming? | What does this mean? What are the advantages and disadvantages? | Technology | explainlikeimfive | {
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"It simply has to do with strictness. A strong typed language requires precise declarations where as a weak typed language does not. In PHP for example $ represents a variable and it can be any type. We can assign $myname = \"me\" or $myage = 20 and PHP automatically recognizes that one is a string and the other is an integer. But in Visual Basic we need to define the variable type before we can assign a value so, dim myname as String and dim myage as Integer, then we can assign the values myname = \"me\" and myage = 20. Thus, PHP is weak typed and Visual Basic is strong typed. This strong and weak paradigm extends to all assignments including how values are passed to and returned from functions and objects. Some languages incorporate levels of strength and can be useful to require explicit declarations to intentionally produce more or fewer errors."
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7aa9nz | How are car batteries able to be charged up with a jump start, if Car Batteries use chemicals for energy? | I am confused about Car Batteries and how they get external charged by other electrical sources if a car battery's electricity is chemical based. Can you eli5? | Chemistry | explainlikeimfive | {
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"The jump start doesn't charge the battery, it just starts the car. When the car is running, it charges the battery.",
"In a battery, you have electrons moving from one of these chemicals to the other (it's a one-way road), and that motion is the \"electricity\" we use. Think of the chemicals as workers : when they run out of energy (let's say they ran out of food), you do not need to get new workers, but could get them food instead. That's what the charging process is about : you are bringing electrons back to the part of the battery that has been losing electrons while you were using it."
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7aaagx | how to count cards. | Mathematics | explainlikeimfive | {
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"The principle is quite simple. You have a better chance of winning a hand of blackjack if there are lots of high-value cards left to be dealt. The dealer plays a fixed strategy, and having lots of high-value cards left makes it more likely that the dealer will bust and you'll win. So you keep a count as you see cards being dealt, adding 1 when you see a low-value card dealt, and subtracting 1 when you see a high-value card dealt. The higher the current count is, the more likely you are to win and the higher your bet should be. You can get more complicated rules for better results, perhaps counting some cards as 2 points or 0.5 points, but that's the basic idea behind it."
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7aaex0 | Decimal factorials | I understand how factorials with integers work, but how do you calculate factorials with decimals? Aren't there an infinite number of decimals between any 2 integers? | Mathematics | explainlikeimfive | {
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"Using the [Gamma function]( URL_0 ). The Gamma (Γ) function is a continuous function that fulfills the following requirement for every positive integer n: Γ(n)=(n−1)! So you can calculate the factorial of any real number X by calculating Γ(x+1)."
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7aaiv9 | what is the final factor when you die of "natural causes" | Biology | explainlikeimfive | {
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"basically organ failire. dying of something like a heart attack or kidney failiure is natural causes if you die at 20 or 80. if its an internal cause thats not causes by any external disease or external chemical factor..."
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7aaot9 | Why do pots sometimes fall in the middle of the night, even if you put them away just fine? | Other | explainlikeimfive | {
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"Fall in what way? Are you hanging them up, or putting them away in a cupboard? Heavy vehicles (especially the kind that typically are used at night) can cause vibrations in the ground, which could disturb them. The ground and your house itself will contract a little bit as well due to the lowering temperature at night, which can cause small shudders that could jostle things. This is from what most of the old creaky house noises originate, alongside the wind and combined with the relative silence of the time it occurs compared to the noisier daytime where similar noises would simply go unnoticed. Or you could have rats."
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7aay7a | How do people can make a game console emulator and how they extract game files from physical cartridge to digital files ? | Other | explainlikeimfive | {
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"First up: emulators An emulator takes the machine code on a cartridge and either interprets it - that is, translates it piece by piece as it runs, or uses JIT compilation to translate it. The second one is much more complicated, but often more efficient. They can translate like this as often the CPU is not custom, and the GPU is either simple (for older consoles) or is not too far from industry standards, as this makes it more likely for developers to make games for the console. The switch, for example, runs on almost the same processor as the nVidia shield tablet. As it is being translated, it also runs on the computer. This is the main reason that emulators for new consoles need so much more power than the actual console - they need to translate the code as well as run it. Second: Game files This is usually done with an adapter, it will be detected as storage by a computer and copied across in its entirety. If necessary, it can then be adjusted slightly for use with an emulator. Of course, nobody would *ever* distribute such a file, as that would be a breach of copyright law.",
"Think of programming an emulator like you would create a virtual version of a computer. You'll sort of create a CPU, a GPU, even RAM depending on what you are doing, and the BIOS: that means you program what the machine should do when you turn it on (e.g. memory checks, load data from the cartridge, etc). And then you'll get the raw binary indictive from the cartridge and run it through your emulator. There's a blog detailing how a very smart guy made an awesome Gameboy emulator that runs on your browser: URL_0"
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7ab1rx | how Marijuana gets you "high" | Biology | explainlikeimfive | {
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"Mandatory \"I'm a doctor\" disclaimer. In your body you have cannabinoid receptors scattered throughout your physiology (CB1 in the CNS and CB2 in the PNS). These cannabinoid receptors are specifically designed to be triggered by a substance manufactured by the body (endogenous) called anadamide. Anandamide that has many functions within the body associated with fertility and immune function. Current working theory is that the level gets extremely high right after childbirth. Common side effects of marijuana intoxication include short term memory loss, increased appetite, Euphoria, and paranoia. The same side effects would be beneficial immediately after giving birth including short term memory loss causing you to forget the pain you just endured, increased appetite to replenish lost nutrients during childbirth, euphoria making you happy with your new baby, and paranoia preventing anything detrimental happening to the child. Again, this is working theory, and there is a lot of research currently in the subject.",
"It contains a chemical (called Tetrahydrocannabinol aka THC, the white dusty crystals). When that is inhaled or ingested, the chemical gets into your blood stream. THC is a psychoactive thing, meaning that when it gets into the human brain, it causes a reaction that messes with the brain. Depending on who you ask, THC may be there to protect the plant from being eaten - predators wouldn't want to go back to something that made their heads go weird. It just so happens that some humans like the reaction it causes!",
"I'm at work right now so I will come back to edit and provide sources. We have cannabinoid receptors. When synapses in the brain \"fire\" a chemical is released to these receptors that prevent that from firing again for some time. THC blocks these receptors and allow these synapses to fire multiple times without a resting period. So if I remember correctly, these synapses are all firing randomly. This effect take solace in the reward center of the brain. I found a nice [video]( URL_0 ) that'll help anyone understand.",
"Dopamine is one of the brain's most important painkillers. When you're not in pain, the brain releases neurotransmitters into the system that inhibit the release of dopamine. When you experience pain of sorts, your brain releases a natural cannabinoid called anandamide that binds to the receptor that triggers the release of the inhibitory neurotransmitters, which allows dopamine (uninhibited) to then flow freely into the brain's synapse. When you smoke cannabis, THC (the main psychoactive compound in cannabis) mimics the natural cannabinoid anandamide and binds to the same receptor that prevents the release of the dopamine inhibitors. It doesn't mimic the actual neurotransmitters like dopamine and serotonin (the way drugs like meth and cocaine do) and so it doesn't cause your brain to work in reverse, which is why using cannabis in moderation doesn't appear to do any seriously long-term damage to your brain. This is a cool interactive explainer on how different drugs affect your brain that we used in middle school health class (requires flash): URL_0"
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7ab6yw | How does a company separate from a parent company, or rather, how is the parent company compensated for the lost value? | Economics | explainlikeimfive | {
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"Any company, be it parent or a subsidiary/child company, has shares, meaning who owns the company (Simple way to imagine it would be- if a company has 100 shares, each share is 1% of the company, limited liability companies simply have owners, who own some % of the company). The shareholders can be other companies, or physical people. If a majority of shares are owned by another company (more than 50%), it is a parent company. In order for a subsidiary to gain independence from the parent, someone else needs to obtain a majority of shares from the parent. When people say that a company separates from it's parent company, it, most likely, means that the parent has sold its shares in the subsidiary and the subsidiary has a new majority shareholders, and the parent has been compensated for these shares. Also, to discuss one of your examples, in case of Bungie, Microsoft retained its right to the Halo franchise, which was most of the compensation, while still remaining a minority stakeholder. So Bungie came to an agreement with Microsoft, that it would give up the franchise for it's own independence, since franchises like this are worth more than any physical assets the company might have had. You might think that a large part of the value of the company came from the employees that worked and developed at Bungie, however people can't be classified as assets, therefore the only real value in the company were its franchises."
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7abey2 | Since US coins were originally made of valuable metals, why are nickels worth less than dimes despite being larger? | Economics | explainlikeimfive | {
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"Contrary to other answers here, it's *not* to make the value of the metal in the nickel equal to five cents! The real answer is apparently government pork. The first nickels were minted at the end of the Civil War, when gold and silver were being hoarded. The US government introduced copper+nickel coins whose value as metal was much less than the value printed on them. The first was a 3-cent piece, and the 5-cent nickel came soon after. The director of the US Mint at the time wanted to make a nickel weighing less than 3.9 grams, but a congressional committee upped that to 5 grams. The congressmen said this was to make it a nice round number in the metric system, but it just so happens they were good friends with wealthy industrialist Joseph Wharton, who had a near-monopoly on nickel mining in the US. Wharton's congressmen were also the folks who suggested the 3-cent nickel piece in the first place. So it seems that the nickel is big because congress was in the pocket of a guy who wanted to sell more nickel. URL_0"
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7abgzv | If plants create oxygen with energy they get from the sun, how do they make oxygen or get energy when the sun is not out? | Biology | explainlikeimfive | {
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"In short, they don’t. During the day plants combine carbon dioxide and water to make carbohydrates (oxygen is a byproduct of this), some of which are burned then for energy and some of which are stored (in sap etc.) or used for growth. During the night, most plants don’t do much growing, and use the stored carbs to keep themselves ticking over. During this time they use more oxygen than they are producing.",
"They don’t “make” oxygen. The oxygen we breathe comes from the light reactions in photosynthesis. Basically, to capture the energy of the sun, they split a water molecule (H2O). They steal some electrons from it and use the suns energy to excite those electrons so they can do useful work. When the water molecule gets split, two oxygen atoms meet to form O2 which is where oxygen comes from. This part of photosynthesis occurs when light is present, so during the day",
"They get energy at night by burning sugars just like us. They take in oxygen and expel carbon dioxide. Photosynthesis isn't to give the plants energy, it's using sunlight to build sugars out of carbon dioxide and water. Oxygen is a waste product, not something that they are exactly trying to make. It just so happens to be quite a useful waste product that they can then use to burn sugar with, just like carbon dioxide is a useful one that can be made into sugar. Photosynthesis to make more sugars obviously does not happen at night, which is why plants need light in the first place."
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7abkud | Why are most canned foods high in sodium? Doesn't the canning process eliminate the need for preservatives? | Chemistry | explainlikeimfive | {
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"Eh. Not entirely. A few things. First, depending on the food we're talking about, salt might be an inherent part of the process, either of canning in particular or just the food in general. Pickles? Olives? Gotta have salt. You just do. Salt is also a critical ingredient in any number of fermented foods, many of which are canned. Second, salt is a flavor enhancer. Processed food manufacturers have tended to add loads of salt to a wide variety of foods for the better part of a century as a way of making their products tastier. Canned foods are hardly unique here. Third, while canned vegetables are certainly saltier than their raw counterparts, they're not necessarily as salty as you might think. [One 30g slice of white bread]( URL_0 ) has a little less than *three times* as much sodium as [28g of canned green beans]( URL_1 ). Fourth, while canning certainly *tends* to kill biological organisms, it's not magic. Some organisms are merely weakened. Some may even survive, though in small enough numbers that they can't cause a problem if the food is eaten within a year or two. A little salt goes a long way towards ensuring that fewer bacteria survive, and those that do stay dormant. But lastly, bacteria aren't the only things that contribute to food spoilage. There are other chemical processes that have nothing to do with bacteria that can make food go bad, or at least lose quality over time. Discoloration comes immediately to mind, but that's not the only thing. Flavors can change. Textures can break down. Foods can take on flavors from their containers. Salt creates an environment inhospitable to bacteria, to be sure, but it also tends to interfere with some of these other processes, making it useful as a preservative even in a largely sterile environment.",
"To make up for the flavor lost when processing and storing. Even though the nutrition value does not really change, the flavor does. Sodium is very versatile. For example normal salt (sodium chloride) for a salty taste, but also msg (monosodium glutamate) for umami. Most processed food flavorings contain multiple sources of sodium.",
"The canning process kills a lot of bacteria but it also kills flavor and introduces a small amount of bitterness to the food. This is countered by adding salt because it's one flavoring ingredient that is chemically stable.",
"~~Too lazy to find the article, but~~ I remember reading that bitter compounds are produced in the canning process. To balance out the bitter, additional salt is added for flavor. I believe the article was on researching chemicals that act as 'bitter blockers'. The idea was that they could be added to canned foods to balance the bitterness without all the excess salts. Edit: [Found the Article from Discover, 2005]( URL_0 )",
"Humans also have what is known as a 'bliss point' in which foods are perfectly balanced and we love them. It's true for sugar and salt. So food companies want to give you that 'bliss point' and they have been engineering food for years to have fat, sugar and salt levels that make you achieve said 'bliss point' and crave these foods time and time again. Finland realized that they were eating too much salt in the 70s and started an informational campaign on lowering salt contents in their foods and making better labels to indicate if the food had high levels of sodium or was healthier. The government informational campaign, along with their food industries, were able to lower their population 'bliss point' for salt and their sodium intake diseases has gone down. URL_0 also, people traveling to the US often say that their find american food extremely salty",
"Canned soups are produced in retorts. Effectively, these are giant pressure cookers with two main variations: Rotary and Hydrostatic. Hydrostatic, as the name implies, keeps the cans static during the processing. Rotary, as the name implies, rolls the cans in a big spiral to help mix the soup. Because rotary mixes the soup, processing times can be much shorter than hydrostatic. Static cooking can sometimes be 9 times longer than rotary. Another way to think of this is that rotary induces convection in the can whereas hydrostatic only induces conduction. Both process at temperatures well above boiling. These high temperatures for 90 minutes or more sterilize the food. There's a lot of science that goes into pinpointing exactly how much time and temperature needs to be applied to the product to make it safe to eat. However, major food companies obviously prefer to err on the side of overcooking because that ensures their products are safe for the masses. It is important to note that, at least in canned soup, *sodium does not play any role in the safety of the food.* Food safety of the canned products are 100% guaranteed by the heating process they undergo. Salt content is just for flavor. Many products lose their flavor in steam retorts over long periods of time. Something that doesn't lose its flavor at these high heats is salt. Sodium is universally delicious, present in almost every cuisine in some form or another. It's a cheap way to build back some of the flavor that is degraded from the retorts. I think it's been very clear in the last 20 or so years since more evidence has come out about how sodium influences high blood pressure, more consumers are trying to lower sodium in their diets. Even the RDAs by the US Government have lowered the maximum limit of sodium in one's daily diet. As a result, many companies have tried to lower sodium in their products. Retort technology is improving, slowly but surely, so I anticipate that sodium will decrease over time in canned foods.",
"For a five year old: When you can foods, they get exposed to a lot of heat and pressure. This destroys a lot of the compounds that give food it's flavor, so canners add in lots of salt to try and make up for it. The salt can also extend how long it's good for.",
"It would be helpful to know which foods you mean. Canned vegetables, for example, aren't typically high in salt - I checked my nearest supermarket's website and the figure for carrots is exactly the same (0.1% sodium) canned or loose. Canned peas contain less salt than frozen, though frozen peas are still less than 0.2% salt. Tinned tomatoes contain less salt than fresh, and chickpeas again have essentially the same amount (i.e. virtually none) between canned and dried. I thought maybe the story would be different for meat, but canned sausages contain less (1.28%) sodium than fresh packaged sausages (2.2%), and their meatballs in tomato sauce contained only slightly more than their fresh, packaged meatballs (without sauce) - 0.8% vs 0.7%. I'm especially surprised by this because I'd have thought meatballs that have been prepared with sauce would be quite salty (they are when I make them!) Maybe the story is different in other countries, but it would be helpful if you could cite a few different foods that are saltier in cans than their fresh/dried/frozen counterparts.",
"Salt makes the food taste better by enhancing other flavours. Better tasting food sells better. Companies want to sell more.",
"During the creation of corn syrup, they add a strong acid HCl to maximize the amount of sugar that they can extract out of the corn. Later in the process, they add a strong base NaOH to neutralize the acid. The combination of the acid and the base create salt NaCl and water H2O."
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7abujp | Why is a decreasing population considered a bad thing for a country? | Why is a decreasing population seen as a negative for industrialized countries? Doesn't increasing automation technology mean that with less people everyone will have more? Surely cities being less crowded with higher average wealth is a positive? What am I missing? | Economics | explainlikeimfive | {
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"People are an input into the economy, just like oil or farm land or machines. As a general rule, the more people you have, the more you can produce. So, on a surface level, a shrinking population is bad for an economy in the same way that a dwindling oil supply or lack of capital is bad. Unlike most of those things, people also create demand, not just supply. So fewer people can also mean that people aren't out there looking to buy new stuff---especially land and houses. which can also upset the economy quite a bit. On top of that, shrinking populations also usually mean aging populations. As people get older they tend to go from being net producers to net consumers, especially when health deteriorates. This can force a country to make hard choices about how, and how much, to support an older population that increasingly can't support itself. This is made worse by the fact that some jobs simply aren't suited to older people (There are very few 80 year old coal miners, or 70 year old ER nurses, and even when people are only 40 or so they may find that family and health makes it hard to work the kind of job or hours they could have worked when they were 50.)",
"The most important factor is that these are the young generations which decrease in numbers. A small generation of kids now will have to support the bigger generation of their parents in a few decades. Population ageing is already a big problem in industrialized countries, and it's only getting worse.",
"Because it means in future years there will fewer people to tax and fewer people to buy goods and services to keep the system going.",
"Many industrialized countries have welfare systems where younger workers pay taxes for programs to assist the elderly. If the ratio of elderly to workers gets out of wack, the government either has to cut benefits to the elderly, raise taxes on workers or borrow money.",
"The negatives of a declining population are that there are fewer people for the lower-tier jobs, even though demand for those jobs remains high. 30-year-olds don't want to do jobs that 20-year-olds tend to do; fast food/restaurant industry, construction, manufacturing, services industries (call centers, secretaries, cashiers, etc). This is largely due to the fact that they have already worked in those fields, or have experience/education that allows them to bypass those fields. Yes, automation helps, but it isn't at the point where we can rely on it to replace a rapidly ageing work force. If these kinds of jobs make up the backbone of your economy (like farming does in the US, for example), your economy is going to suffer. This is a bad thing. However, there isn't a country on the planet that is in real fear of any of these problems at the moment. It'll likely even out really well in places with high quality of life measurements.",
"A decreasing population doesn't result in more jobs for fewer people. Because there are less people, fewer products will be needed, therefore fewer factories and resources will be needed for those products, therefore fewer jobs will be needed to run those factories, and then a new equilibrium is established where people are once again saying \"there aren't enough jobs for all these people\". At the same time, you have that peak generation right before the population decrease thats too old and weak to work, with not enough production to support it, but they still consume resources, so everyone becomes poorer overall. Also, while automation is increasing, it is nowhere near where it needs to be for our society to become a utopia running on auto-pilot. Still a ways to go. Until we all have Mr. Handys, you better get to work."
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7abvq2 | What is the point of the standard deduction in tax returns? | Economics | explainlikeimfive | {
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"The Congress created the standard deduction in 1944 to make tax filing simpler for most Americans. Rather than keep receipts and fill out complex paperwork to file for dozens of specific deductions, the standard deduction allowed a taxpayer to just reduce his/her taxable income by 10%. The Congress in 1964 changed the deduction to a dollar amount, so as to permit the poorest Americans to avoid paying taxes altogether. The deduction still serves those dual purposes today -- making filing simpler for most Americans, and eliminating tax liability for the poorest Americans. URL_0"
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7ac3h0 | WoW's current expansion, Legion, has been trademarked a day before announcement. WoW's next expansion is likely to be announced tomorrow (and still hasnt been trademarked). How can that be "safe" for them? | Other | explainlikeimfive | {
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"1. If you don't know what the next expansion is called, how do you know they haven't trademarked it? 2. The scenario you describe is possible. It's a subset of \"cybersquatting\" (the more common scenario being the person who registers a domain associated with someone else, usually to hold it for a high ransom). The US has laws to try and thwart this, but they're not always successful. Blizzard has deep pockets and the squatting person would have to find some sort of legitimate use to avoid losing their trademark, upon which Blizzard would just scoop it up."
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7ac6mx | What makes rejection cause the brain to desire a person more? In what ways can you combat this responsive behavior? | Other | explainlikeimfive | {
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"It may help to be conscious of the fact that the brain is not a passive recipient of emotion. In fact, the brain doesn’t react to stimuli based on emotion at all, it is in a mode of constant prediction and then compares its prediction to the stimuli and adjusts or filters from there. It’s powerful to know that the brain is actively creating emotion on the go, and that this creation of emotion is largely influenced by affect, the bodies general sense of being. If you are interested in understanding the contemporary science behind emotion development I highly recommend “How emotions are made” by Lisa Barrett"
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7aceea | Why do white Lego bricks turn yellow-ish over time? | Chemistry | explainlikeimfive | {
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"Some plastics are not UV stable (ultraviolet light damages or degrades the material), look at stuff that sits in display windows hit by sunlight for extreme and obvious examples. This causes discoloration over time (and/or cracking), either fading of the color or whites yellowing.",
"Plastic often has additives to give it better properties for its function. For example a form of Bromine is often added to make plastic more flame retardant. These additives are not 100% stable within the plastic and over time can react and change to form other substances, causing discolouration. This is most obvious with white plastic and I would guess is the reason why white Lego bricks become yellow-ish."
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7acl5p | How is life expectancy calculated? | Is it a simple average of the age in which all people die including babies who die young, e.g. SIDS? What got me thinking about this was the fact that the life expectancy would be pulled downward by things like babies dying or college guys doing stupid shit. However, once you make it past those stages are 40, then your life expectancy is higher than that average that includes these folks. | Mathematics | explainlikeimfive | {
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"> Is it a simple average of the age in which all people die including babies who die young, e.g. SIDS? More or less, yes. > What got me thinking about this was the fact that the life expectancy would be pulled downward by things like babies dying or college guys doing stupid shit. However, once you make it past those stages are 40, then your life expectancy is higher than that average that includes these folks. Again, yes. This is why life expectancy long ago was so low. High infant mortality. Once you survived past childhood, your life expectancy was very similar to what it was today, but the high death rate among the young drew the average down.",
"There are two ways to measure life expectancy: what is the average age that people die at, and given that you are age X, you on average can expect to live Y more years. With the first one, you are correct, it will include infant mortality. But if you take a look at the [actuarial chart]( URL_0 ) the US Social Security Administration uses, you will see that the longer you live, the higher your expected age at death is. A baby boy born today can expect to live to be 76, but a 60-year-old can expect to make it to 81."
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7acq9a | Why does the propensity for motion sickness increase as you get older; e.g., riding roller coasters or other rides at amusement parks? | Biology | explainlikeimfive | {
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"Balance is controlled by a group of small organs in the ears, called the vestibular system. These organs detect two different kinds of motion: rotation and movement in a straight line. The way straight line movement is detected is that there are tiny little bones shaped like bits of stone that sit in a kind of sac that is lined with tiny hairs. When you move in a straight line, the little stones press against the hairs, which send signals to the brain that say “hey, we’re moving forward!” or “hey, we’re tipping over!” The way rotation is detected is with three rings inside your ears. These rings are filled with fluid and more tiny hairs, and they are arranged in a way so that no matter which direction you move, the fluid presses on the hairs, too. So, if you did a cartwheel, one of the rings would say to your brain, “hey, we’re doing a cartwheel!” If you spin around like a ballerina a doing a pirouette, a different ring would tell your brain, “hey, we’re doing a pirouette!” And if you nod your head up and down, a third ring tells your brain, “hey, our head is nodding!” The fluid in our ears is roughly the same as blood. Sometimes, that fluid thins out, which makes movements seem more intense than they actually are, which can cause problems with balance. Sometimes the little hairs in the organs will break away, and the spot where they were either sends too many signals to the brain, or none at all. This can also affect balance."
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7acunj | The Combined Federal Campaign and what they do? | Economics | explainlikeimfive | {
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"It's the federal government's charity fund raiser (it's also the world's largest and most successful annual workplace charity campaign). They combined all the agencies separate charity fundraisers into one combined effort. Federal employees designate to have charitable donations removed from their next year's paychecks (in the past they could donate directly, too). Many agencies have some fun attention and fundraisers (like a talent show, or casual Fridays if you make a donation)."
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7acv4v | Tax Cuts and Jobs Act proposal | Middle class myself, I've been trying to wrap my head around this the last 10 minutes but just cannot seem to figure it out. | Economics | explainlikeimfive | {
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"So, one of the things that the Republican party is doing right now to try to look a little more competent and generate buzz is that they're passing the same bill back and forth between the house and senate as a skeleton outline. In the process as usual, what happens is that one of the two chambers writes a bill (and there's a bunch of rules about who starts what bills), then they send it to the other house to either be approved, amended, or rejected. If it's amended, it's sent back to the first house. So if the House passes a bill, it goes to the Senate for approval, and if the Senate amends it instead, it goes back to the House, who can amend, pass, or leave it. What they are doing right now is passing 'skeleton' bills. They're taking turns adding a detail and then passing it as a way to highlight the 'high points' in the bill and to convince people to get onboard with it before the other shoe drops on the costs of the bill. So far, the high points include: 1. They're going to change the number of income brackets from 7 to 4. This includes a massive tax cut that scales up for the more wealthy, and a tax increase for part time minimum wage earners (the poor). If you work full time, you will experience a tax cut. 2. They are doubling the standard deduction, so for most people it will almost always be cheaper to take the standard deduction than to try to file a long tax return unless you're so rich that you'd hire someone to do this for you anyway. 3. They are eliminating the dependents deduction. If you have 1 or fewer kids, the standard deduction doubling will more than compensate, but if you have three or more kids, unless you're pulling in hundreds of thousand of dollars a year, the tax cuts and jobs act will be a tax increase. 4. They are increasing the child tax credit. The dependents deduction is like ~~8~~ 6-7 times the size of the increase though, so you won't notice it. 5. It reduces but does not eliminate mortgage and property deductions. Any homeowner will notice a squeeze on this side, but landlords who are paying dozens of mortgages on rental properties will probably be bankrupted by it. 6. It repeals the estate tax, so that when the super rich die (the estate tax only ever affected the top 0.2%), their entire vast fortunes are inherited whole by their children, instead of a share going to the government. But I urge you to keep in mind that this is just a skeleton. This isn't the bill's final form, and not only are all of these points up in the air, but they are using this to delay announcing the drawbacks and downsides of the bill. Try to keep from mentally evaluating it until they do, because like with part timers, 3+ child families, or real estate speculators you may yet find that you'll get a tax hike out of this bill, and they haven't yet made clear how they are going to pay for this massively expensive tax cut either."
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7ad7oj | Why does food, meat and dairy in particular, smell worse cold than hot? | Chemistry | explainlikeimfive | {
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"I’m a cook and i genuinely ask myself this everyday I open a bag of cooked chicken breast. Someone please answer this lol."
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7adag9 | Why is it called The World Series? | Other | explainlikeimfive | {
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"The best baseball has always been played in the USA. Baseball was invented in the USA, and while other countries play baseball, the highest level of play is in Major League Baseball - with 29 teams in the USA and one team in Canada (the Toronto Blue Jays) The World Series was first referred to as the \"The Championship of the United States\" and also the \"World's Championship Series,\" which later shortened to World Series. While the two teams contesting this year's World Series both represented American cities, they had players from the USA, Latin America, and even a couple of players from Japan (notably Yu Darvish and Kenta Maeda of the Dodgers)"
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7adeul | Why the common logarithm base is 10? | I know that it's because engineers used 10 a lot but it just doesn't seem to be a good reason to me. | Mathematics | explainlikeimfive | {
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"It comes from the days of slide rules. To see how a slide rule works, imagine trying to perform basic addition by using two normal rulers. To add 2 + 3 you could find 2 on the first ruler, then line the end of the second ruler up with it. You then find the 3 on the second ruler and see what number it lines up against on the first ruler: 5. Slide rules use the same concept, but instead of adding simple numbers it adds the log of numbers. This is useful because of the identity that Log(A) + Log(B) = Log(A\\*B). That means that we can convert a multiplication problem into an addition problem, then solve that addition problem using the ticks on a scale. There's an issue with this, though: what happens if you try to add 13+13 using 12-inch rulers? You run out of space! To avoid that same problem from happening on a slide rule the operator is expected to keep track of the powers of 10 themselves. This is why scientific notation is used–it's the exact format that's conducive to using a slide rule! This means that instead of computing 127\\*7,891 you would use the slide rule to compute 1.27\\*7.891 and then manually compute 10^2 \\* 10^(3) (which is just 10^(5)). You split the logarithm up into an easy-to-compute whole number and a difficult-to-compute but finitely sized decimal. That only works when it's really easy to compute the whole number. If we use base 10 for the logarithm then that's as simple as counting the digits (or, in scientific notation, it's just given to us). This makes the base-10 logarithm the obvious one to use. It's also worth noting that once you can compute one logarithm you can compute any logarithm. If you want the base 2 log just take log(n)/log(2). Since you only need one logarithmic scale on a slide rule it makes sense to use the one that helps other operations most directly.",
"well its not just engineers, we literally operate on a base 10 system. That is why we count from 1-10, because we have 10 fingers. Logarithm base 10 tells you the order of magnitude (how many digits your answer is going have), and is thus extremely useful for visualization.",
"Is log 10 really more common than log e, aka ln?"
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7adiqe | Is it "couldn't care less..." or "could care less..." Why? | Other | explainlikeimfive | {
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"\"I couldn't care less\". \"I could not care less\". means that you are at the bare minimum of caring. saying \"I could care less\" implies that you care at least a small amount, as it would be possible for you to care less. Both are accepted colloquially, but \"couldn't\" is correct."
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7adjo4 | How is a satellite able to transmit so many channels in HD/SD to so many TV dishes across the globe at once? | Technology | explainlikeimfive | {
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"It doesn't have to transmit to each dish. It transmits each channel a single time, and then as many dishes as there are can listen. It's the same for radio or other broadcasting technologies. This is opposed to streaming, with say Netflix, where Netflix servers need to send continual two way traffic between their servers and each user for a personal stream. A satallite could definitely not handle with traffic to the user base of satallite TV. As an analogy, satallite TV is a guy with a megaphone communicating a message to a crowd of 1000 people. Netflix is 1000 messnager carrying out a conversation with 1000 people to convey the same message.",
"The number of dishes receiving it doesn't matter. Satellite TV is a broadcast system, it just sends the signal out for anyone with the right equipment to receive. It's not like the Internet where it has to send a separate copy of the data to each user."
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7ae0qe | How come we can go days without water, weeks without food, but only minutes without oxygen? | Yeah i know that this question is probably stupid but im still curios | Biology | explainlikeimfive | {
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"It's the fuel our body uses for all metabolic, or energetic, activities. If you disconnected gas from your engine your car wouldn't work, same goes for your body. Oxygen allows everything else to work. Food is stored in fat in the body and sugar in glycogen in the liver so you have stored up nutrients. Same for water, there's places your body can store both food and water but the only place for air is in the lungs and it's the most vital and runs out quickly."
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7ae5e1 | Why do raccoons steal/collect/wash things? | Biology | explainlikeimfive | {
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"The stealing and collecting should be self-evident: They are scavengers and that is how they get their food. Why exactly they wash their food is less obvious. Previously it was thought this was to remove debris but that doesn't check out because they don't wash dirty things like earthworms. Instead it seems they lack ridged texture on their paws and have somewhat poor eyesight, so dunking the object in water will allow them to feel the texture and determine what exactly they have grabbed better than if their paws are dry."
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7aehxp | [Physics] How do we know the speed of light is constant? | For example, time dilation illustrations require the speed of light to be constant. How do we know this? Especially when scientists have successfully slowed down the speed by changing the medium. Thank you for your help. | Physics | explainlikeimfive | {
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"The speed of light is the speed light travels in a vacuum. So changing the medium doesn't invalidate the constant.",
"Scientists can't slow the speed of light down. Changing the medium just makes the light take a less efficient path through. But its going the same speed. and we know it is because we can measure it. We had all these mirrors put on the moon and would send a laser at them, and measure the time it took to reflect back to us. This was consistent with things like the amount of time between seeing an explosion and hearing it.",
"> How do we know this? We can measure the speed at which light travels. It is invariant with respect to the movement of the observer. > Especially when scientists have successfully slowed down the speed by changing the medium. The speed of light refers to the speed of light in a vacuum. When you are measuring the speed of light in a different medium, you aren't, actually, measuring the speed of light. Rather you are measuring the propagating interaction of the electric field from the light, with that of the material. The light itself has essentially ceased to exist as a unique entity."
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12,
6,
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7aeuka | Do we loose/gain blood vessels/veins as we grow/shrink throughout or life or are they always there? | Do we have the same amount of blood vessels/veins in our body throughout our entire life span? How about when someone looses a lot of weight or gains a lot of weight? Does our body make more veins and vessels for the increased size we become? What happens to the veins/vessels when we shrink? | Biology | explainlikeimfive | {
"a_id": [
"dp9fnhk"
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"text": [
"They can change. You can grow new blood vessels through a process called neovascularization for a variety of reasons. One well known one is that if you wear nonporous contact lenses for too long you starve the cornea of oxygen. In response the body grows new capillaries. This combats hypoxia in the tissue but you can't see through them. I don't know what the reverse process is called but you can lose blood vessels as well."
],
"score": [
3
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7af9dw | How did old guitar effect pedals actually produce effects such as reverb & delay? | Technology | explainlikeimfive | {
"a_id": [
"dp9k52t"
],
"text": [
"I'm not too sure about delay, though there were some 'tape delay' units that worked like cassette tapes, except the tape was in a small loop. It had both a record head and read head running on one tape, so it would record the input from the guitar and play it back after a short delay. You could adjust the delay by adjusting the tape speed. In theory you could adjust the delay by changing the distance between the heads also, but I'm not sure if this was done as it would be more complicated. For reverb the old school way (might have been others) was called spring reverb. They stretch a string between two moving coils, which work similar to how a speaker and microphone work (electrodynamic speaker and mic, anyway). One end of the spring is vibrated by applying the input signal to the coil, making it move like a speaker. The waves would run down the spring and go back and forth, and interact, kind of like how sound waves would bounce around a room and interact, and reverberate! At the other end of the spring, that coil would be used as a microphone to pick up the sound and add it back to the signal that's being fed to the amplifier."
],
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11
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|
7afcly | What is the ozone hole and why does it matter that it's so small? | Other | explainlikeimfive | {
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"text": [
"The Ozone layer is a part of our atmosphere made up of Ozone (which is a molecule with 3 oxygen atoms. Oxygen in the air we breathe is O2, Ozone is O3). It is important in that it protects us from the full blast of Ultraviolet rays that come in from the sun. Back in the 1980's we noticed that there was a gap, a hole in the ozone layer near the south pole. It was determined that some of the chemicals we use (Chloroflourocarbons or CFC's) were the cause of this. These were commonly used as propellants in spray cans, like cans of hair spray as an example. As we started reducing their use, the hole in the Ozone layer has actually been getting smaller (which is a good thing).",
"The earth is this ball with small creatures on it. This ball is covered by a bunch of layers, and in one of them is the ozone, the ozone has a normal thickness of 300. It's job is to protect the creatures on this ball from direct sunlight called \"ultraviolet rays\". When the creatures use chemicals like \"CFCs\" (Fridge cooling, Air conditioner, etc...) gases fly up to the ozone and decrease it's thickness (not causing an actual hole) from 300 to something lower than that. and by this the direct sunlight will be more powerful than the ozone and it will hit the creatures which will cause blindness, skin cancer, etc..."
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10,
4
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7afd6e | For drug junkies like meth and heroine addicts, how do they lose their teeth? | Biology | explainlikeimfive | {
"a_id": [
"dp9hmbi"
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"text": [
"I believe it's something to do with the dry mouth effect (for meth at least) and also the consequent neglect of basic oral hygiene that comes with addiction"
],
"score": [
3
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|
7afedy | How/why do we lose our voices? | After a night of loud shouting/singing at a concert I have sometimes lost my voice. What is actually happening and how come it only takes a few days to come back? | Biology | explainlikeimfive | {
"a_id": [
"dp9iet9"
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"text": [
"We have folds of skin in our larynx (we call them vocal chords) that vibrate the air. This is what makes the noise part of our voice (our mouth shape also has an effect, which is why when you whisper it still sounds like your voice). When we lose our voice, it's because these folds get inflamed and plump up, so they can't vibrate the way they used to."
],
"score": [
6
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} | [
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7afnv9 | Why are salts like table salt and sodium glutamate flavor enhancers? | Why aren't other non-toxic sodium salts flavor enhancers also? | Biology | explainlikeimfive | {
"a_id": [
"dp9lbdi"
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"text": [
"Glutamate is related to a natural amino acid which the body already produces, and that's what's responsible for the *umami* taste. Table salt and eg salt-free Mrs. Dash® are flavor enhancers because they respectively contain sodium and potassium, which are both *electrolytes*, used to carry signals and impulses to and from the brain."
],
"score": [
3
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7aftjn | what is an “Opportunity-adjusted touchdown” (OTD) ? | Fantasy football | Other | explainlikeimfive | {
"a_id": [
"dp9lrub"
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"text": [
"It measures how often a statistically average player would score, given the same opportunities the player in question has had. It allows you to evaluate whether a player is scoring just because they get the ball a lot, or because they are making plays."
],
"score": [
8
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7ag16e | There are a lot of rats, insects, etc. in our sewage system. How come they don't show up in our toilets? | Other | explainlikeimfive | {
"a_id": [
"dp9nflk"
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"text": [
"There actually aren't many rats in your sewage system if your citiy's infrastructure is fairly modern. Rats aren't interested in swimming around in mostly airless pipes, and modern sewers are not the cavernous masonry structures commonly portrayed in media. That said, rats can and will swim up your toilet if the trip is short enough. So will snakes, crabs, and lots of other weird critters."
],
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3
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|
7aghk1 | Why do pores form on the round red & white peppermints when you suck on them? | Just a curious gal | Chemistry | explainlikeimfive | {
"a_id": [
"dp9sxpv"
],
"text": [
"You dissolve the candy as you suck on it, the sugar being what lends it the taste. As it erodes it exposes bubbles within the candy which are the \"pores\" you notice."
],
"score": [
14
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7agmg6 | is brand name toothpaste bought at dollar stores real? | Other | explainlikeimfive | {
"a_id": [
"dp9sr2f"
],
"text": [
"If it is a Dollar Tree in the US, then yes. They are a great retailer who work with suppliers specifically to develop products that can be sold for a low price. Might be a smaller size, or cheaper packaging, but is legitimate."
],
"score": [
7
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|
7ago0h | How does a magnetic strip (such as on a credit card) store information? | Similarly, is a full swipe of the strip through a reader needed to process the data it holds or does only a portion of it need to be swiped? | Technology | explainlikeimfive | {
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"dp9ut6q"
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"text": [
"You know how magnets have a north pole and a south pole? The mag stripes are made up of small magnetic particles. By applying a strong magnetic field, you can orient the magnetic direction of those particles one way or the other. The particles themselves don't move, just the direction that they are magnetized. When you move the stripe through a reader, the changes in magnetic direction [induce small pulses of electrical current]( URL_0 ) in the reader, which are then amplified and turned into digital data. A stripe can contain redundant data, so you may only need part of the stripe to be read. It depends on the card. There are commonly 3 \"tracks\" on a stripe, where a track is a lengthwise section of the strip. Each of those tracks is used for slightly different things, but 1 and 2 quite often contain the same data. So even if one is unreadable, the other one might be OK. Usually the critical information (such as a credit card number) doesn't go the entire stripe length. So a partial swipe could work."
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6
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7agpix | Why do lightbulbs go out, but not the lights that illuminate screens on TVs and phones? | Is it even possible for them to go out? | Technology | explainlikeimfive | {
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"it is, DLP tvs for example used a honest bulb (though very bright and powerful), and it had a life of a few years. LCD screens use edge lighting, most are LEDs these days (all cell phones), but they used to use compact florescent lights (rarely still do). both have absurdly long lifespans, longer than the devices they are in. but its possible for the backlight to fail. the newest phones (and some TVs) are OLED, which means the screen itself are itsy bitsy LEDs that generate the light themselves. again, super long life.",
"Really the more interesting question is **why do lightbulbs go out** rather than why the light sources in screens don't. Afterall, the lightbulbs 100+ years ago had the same lifespan as modern ones -- why hasn't the material science made any progress there? The answer is that lightbulbs are one of the first, and most egregious case of planned obsolescence. They are *designed* to go out, because if they lasted forever, there would be little demand for new lightbulbs. From 1920s to 1940s the lightbulb makers formed the [Phoebus cartel]( URL_0 ) which explicitly ensured that no manufacturer sold lightbulbs with more than 1000 hour average lifespan. The cartel has gone, but the practice still continues.",
"They most definitely go out. On LCD TV's and less than flagship phones it's called a cold cathode backlight. And it's a physical part, which can fail."
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"https://en.wikipedia.org/wiki/Phoebus_cartel"
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7agzzs | how anesthesia works | I mean the putting you to sleep kind | Biology | explainlikeimfive | {
"a_id": [
"dp9zndw"
],
"text": [
"The specially trained doctor administers three drugs. One reduces your consciousness, making you drowsy, or unconscious or comatose. Another paralyzes the body so it doesn't move during surgery. A third numbs the bodies sensation of pain. Three doctor makes sure you have the right amount of each by watching your vital signs, like heart rate, oxygen saturation, so you are unaware, still, and not suffering."
],
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16
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7ahaj4 | how do people come up with the age of a tree without cutting it down and counting the rings? | Other | explainlikeimfive | {
"a_id": [
"dp9yt31",
"dpa1cbo"
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"text": [
"They take a core sample and count the rings. Also, another tree of the same species could be cut down and counted. The growth in the rings of that tree in comparison to its diamiter would offer a close estimate to the tree in question. The rings will vary in size depending on the growth each year so the estimate wont be perfect.",
"Some trees do not have annual growth rings. (In the tropics, for example.) For these trees scientists take a core sample from the center of the base of the tree. In effect, they're aiming for the part of the tree that was the sapling when the tree was very young. With that core sample they can do radio carbondating. This technique was relatively new ~20 years ago and they dated trees in the Amazon at 1,000 years old. And guess how they calibrate radiocarbon dating? Tree rings! They have data from trees that they know the age of (via counting rings) and use that data to estimate the age of trees, not to mention the other living and formerly living things which they test using radiocarbon dating."
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7ahca9 | it's said that we're not really touching anything because our atoms doesn't touch, so what it is that we're actually feeling when we 'touch' something? | Physics | explainlikeimfive | {
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"> it's said that we're not really touching anything While you can find this claim often, it is highly misleading and needs a very weird definition of \"actually touching\". For all reasonable definitions, we do touch things. The electron clouds that make up most of the volume of atoms even overlap a bit. You are more than just touching an object, you are entering it a tiny bit!",
"This gets asked a lot so you should do a search. It's the force of the outermost electrons in the touching objects repelling each other. When you put your hand on a book to open it, it's the outermost electrons in the outermost atoms of the outermost skin cells on your hand repelling the outermost electrons in the outermost atoms of the cover of the book.",
"> it's said that we're not really touching anything because our atoms doesn't touch Only by people who don't understand physics. Either we touch things, or the word touch has no meaning and should be banned from our language. > so what it is that we're actually feeling when we 'touch' something? You are feeling the repulsion of electrons. From a distance, atoms are electrically neutral, but when you are very close, the negative charge of the electrons is nearer than the positive charge of the nucleus, resulting in a repulsive force.",
"[Sixty Symbols did a lovely video on this topic.]( URL_0 ) This idea of \"touching\" doesn't make sense on the really small scale in the same way that we normally think about. This makes the claims that things aren't \"really\" touching itself not really make sense. If two atoms are \"touching\", then they are close enough that the electron clouds of each atom are interacting strongly. Are the electrons touching? Well electrons have no size, so it makes more sense to describe the electrons themselves as the cloud or space that they tend to occupy around the nucleus or at least the area where they can exert a strong force on other charged particles. So are these two atoms touching? Yes. We can define this distance based on different things, but essentially they are touching."
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7ahdom | Is there a difference between clinical depression and depression triggered by a traumatic event? | Biology | explainlikeimfive | {
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"text": [
"Not diagnostically. You’re depressed if you meet all the criteria in the diagnostic and statistic manual of depression. However if you have a traumatic even occur a good therapist or doctor will conduct a differential diagnosis to see if you have what is called an acute stress disorder, adjustment disorder, or post traumatic stress disorder. A lot of things look like depression but could be something else because it’s more complicated than that. Additionally you could have PTSD and depression.",
"TLDR; the difference between clinical depression and depression caused by trauma (reactive depression) is severity of symptoms and the initial cause of the depressive episodes. Major depressive can be caused by biology, genetics, trauma, etc, while reactive depression usually occurs in reaction to trauma and extreme stress. Psychology student, depression sufferer, and clinician here. There are actually a lot of different forms of depression, and they normally differ in diagnosis by how the disorder came about and the length of time it’s gone on for. Here are the majors ones: 1) Major depressive disorder, a.k.a. clinical depression, is what most people think about when it comes to depression. It’s characterized by the classic symptoms of depressed mood, feelings of hopelessness and worthlessness, loss of interest or pleasure in hobbies, fatigue, and thoughts of death or suicide. This form of depression is normally based in a person’s biology and genetics, but can be trauma-based in cause as well. It can develop if other types of depressive disorders are not treated. 2) Dsthymia is characterized by a chronic state of depression that has lasted for at least two years. This is a type of chronic depression that lasts for years on end, but deals with less intense symptoms than major depressive disorder. 3) Reactive depression is a form of depression caused in reaction to trauma, and normally follows along the same general symptoms of major depression, though the severity of symptoms can differ. The main difference is what is thought to be the main cause of the disorder, in this case normally due to trauma. 4) Seasonal depression, or seasonal affective disorder (SAD), is normally attributed to depression caused by the changing of the seasons. 5) Postpartum depression is a form of depression that occurs after a woman gives birth, and about ten to fifteen percent of women experience this type of depression after birth. 6) Bipolar depression is a part of bipolar disorder, which is a disorder in which a person cycles between two emotional extremes of mania and depression."
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7ahi85 | How we found the void in The Great Pyramid of Giza? (how Muon Tomography really works) | Physics | explainlikeimfive | {
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"ELI18+ is the Wikipedia article. There are particles with high energy hitting the atmosphere. In the collisions, muons are produced, tiny particles that don't live long. The muons travel downwards (typically not directly vertically, but still downwards) until they are stopped. Rock stops more muons than air. If you put a muon detector somewhere, the amount of muons you detect depends on how much rock is above you. If your detector can detect the direction of muons as well, you can detect the amount of rock in all directions above you. If you expect 100 meters of rock from the pyramid in some direction, you can calculate how many muons you expect and compare that to the measurement. Fewer muons? - > more muon-stopping rock in the way. More muons? - > Less muon-stopping rock in the way. Repeat that measurement in multiple places and you get a rough idea how much rock is where in the pyramid.",
"A very basic example that physics student do sometimes (provided they have a campus with a mountain on only one side) Take a muon detector point it to the sea-side and count muons. Then point the muon detector toward the mountain and count the muons. You'll see that there is less muon coming from the mountain than from the sea. Now, muon attenuation in material is known, and muons are produced by cosmic ray which have a known spectrum (but a few points with large uncertainties at extreme energies) so you can compute the expected muon rate from a direction. If there is an obstactle on the way you can compute the attenuation of the obstactle. Muon imaging does the opposite, you count the muons arriving, and you deduce the attenuation. The main difficulty is to collect enough muon to see \"small difference\" in attenuation"
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7ahrh5 | Why do domesticated pets have shorter lifespans in comparison to humans? | Biology | explainlikeimfive | {
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"This isnt true for all animals. Many animals when domesticated have much longer lives. Could you clarify what animal you are talking about?",
"Do you mean why don't domestic animals live as long as humans? That's mostly because longevity is super hard to breed for. Because at a certain age, animals stop being able to reproduce. That means there is no evolutionary advantage to living longer than that. Many, like chimpanzees rarely live past the age they run out of eggs.",
"Because animals that are possible candidates for becoming pets are much more desirable as pets if they have undergone selective breeding to enhance their desirable qualities. Animals with short lifespans are much easier to selectively breed because you can raise several generations during one human lifetime, enhancing the desired characteristics a little more with each generation. Longer lived animals are more difficult to selectively breed because you have to wait longer for each generation to come along, with its associated opportunity to select for desirable characterisics.",
"All animals have a natural lifespan. Most animals that we keep as pets happen to have shorter lifespans than humans. The animals that live longer than us are generally ugly and not entertaining - basically not the kind of animal we want to keep around as pets."
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7ahxey | How does stomach acid stay in the stomach? What stops it from mixing with water and getting digested? | Biology | explainlikeimfive | {
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"dpa3f00"
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"text": [
"It doesn't really \"stay\" in the stomach. The stomach constantly produces stomach acid, and the next part of the digestive system, the duodenum, neutralizes the acid by constantly producing a base."
],
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13
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7ahzwl | How is Banksy's identity still anonymous if there are public statements made by him, the location of his house is known, and parties are held to unveil his new works? | Other | explainlikeimfive | {
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"His inner circle is very tight knit. Everybody who deals with him directly has an interest in maintaining his anonymity. For those who interact with him professionally, this anonymity is a still significant contributor to the value of his work. For those who are his friends and family, protecting his anonymity is about respecting his desire to live and work this way. There are photos of him out there, but this tight knit inner circle is effective because there is never a verifiable confirmation by anybody who knows him personally to say \"yes - that's him\". So the photos and \"Is This The Real Banksy???\" headlines are just left hanging out there. Statements can be released through spokespeople. Works done in public spaces might be created by Banksy, but put up by other people. Anyone brought in from outside to be involved in a work will only deal with Banksy's crew, not Banksy himself.",
"Banksy's identity has been known for a long time. Google it. Though a) it's no one you've otherwise heard of and b) he and his people will never confirm it. Ultimately it's irrelevant. I could tell you his name is Bob Sampson a 48 year old builder from Frome. Because you've no idea who Bob Sampson is, that information barely registers to you. Doesn't matter. Only if I told you it was Gary Barlow from Take That would it pique your interest. Thing is, everyone prefers not knowing. His identity already Is Banksy. Outing him fully, with confirmation, would just mean Banksy stops making work.",
"Goldie, the D & B guy said it was 3d from massive attack. he let it slip in some interview, I think he actually said 3d was the boss, but banksy is really a collective. their work appears (or used to) suspiciously close to where massive attack where touring...",
"I watched a show about it not that long ago and Banksy, is not one person. It's a group of people, like a secret club. By being more than one person, it makes it impossible to track them or hunt them down. A lot of people really think it's one person, but it's not. It's a group of artists.",
"I went to the opening of his movie “Exit through the gift shop” at Sundance years ago. While sitting in the theater waiting for it to start I pulled up a google image search of who Banksy is supposed to be on my phone. I looked up and saw the exact same guy sitting 4-5 rows in front of me. The guy left the theater about 15 minutes before the end of the film. After it finished, we all walked out of the theater to find a new Banksy rat painted on the side of the theater. So basically yeah, your google search will provide the actual identity of Banksy but without catching him in the act, he can always deny Edit: Not sure why so many people find this hard to believe. It’s not unheard of for a director to attend the premier of their movie at Sundance",
"Banksy is a collective, though the principal member and funder is likely 3D from Massive Attack. Someone noticed that tour dates coincided with new Banksy pieces popping up in the same cities, either a day before or after the concert. This means that Banksy gets paid ever time [House MD]( URL_0 ) airs anywhere in the world.",
"I've come close to Banksy's circle. There was a weird system where in order to receive something from him, we had to be told it wasn't from him. Whilst we weren't told this, there was a strong indication that Banksy started as one person and then more joined so I'd say it's a group. I wouldn't be surprised if Del Naja was involved. Many Banksy pieces (the 2D pieces on walls) are collages, created by using a laser cutter to make multiple templates built from the image made in Photoshop. Whoever figured out that technique and applied it to street art is the original Banksy. Then I suspect Del Naja or someone like him found Banksy and they had a political affinity, so his work was expanded and costs funded. Because Banksy has committed multiple acts of vandalism, he is likely wanted in many countries for several petty crimes. So it's in everyone's interest that he remain free, hence the lack of confirmation of his identity by those that can prove it. Edit: typo",
"[how I imagine my reaction will be when he does get revealed ]( URL_0 )",
"I love the \"3D is Banksy\" discussion we are having in here because Massive Attack is fucking amazing and maybe it will turn some people on to them.",
"My guess is that people well connected to the art scene know perfectly well who he is, but the \"anonymity' shtick kicks ass from a marketing standpoint, and people aren't going to burst the bubble. You don't talk about fight club. I had a geologist friend that had to do some work in Death Valley. He tells me that one of the first things he was told was basically \"You shall not solve the mystery of the sliding rocks\".",
"I'm of the opinion that Banksy is a team of people and Robert Del Naja of Massive Attack is one of them.",
"There was a tradition in Baltimore for an anonymous man to drink at Edgar Allen Poe's grave every year. URL_0 For what it is worth, graves sit ignored and unvisited 99% of the time. The media made the Poe Toaster story a thing. Investigating the story, I'm quite sure people have seen the Toaster (to prove it happens at all) and they know who it is. They intentionally keep him anonymous because it makes the story more interesting.",
"Interesting article I read after visiting an exhibition: URL_0 (Unfortunately it is German, tell me if I should sum up in English)",
"Used to be a regional rep for a major fine art auction house. The reason that the identity of Banksy isn't known is that Banksy is a contrived concept created by a network of art dealers. There doesn't have to actually be a specific person. Yes, someone makes the art (or a group of people), but attributing the work to a particular real-life human being is unnecessary. Pros for the art dealers include not having to pay 50% of the profit to the artist, and the dealers don't have to worry about the issues they've had with other people, like if an artist dies young or creates a PR problem that impedes the market for the product. (Eg: We squeezed works out of people like Jean-Michel Basquiat, but when the guy dies young, it just doesn't pay off like someone who could have produced 10x the amount of work.) Oh, and no...having limited amount of work isn't better in an enormous and hungry world art market. The movie \"Exit Through the Gift Shop\" is an extension of this brand. The entire movie is contrived with lots of hints to tell you that \"this entire thing is contrived\"...hence the name \"BANKsy\" and the concept that the dealers are directing the buyers like cattle to a purchasing opportunity. The movie was nothing more than a huge advertisement for the brand. This is what the high-end art business is about. We manufacture \"desire\" in a variety of different ways (even having art created) and manipulate the buyers to spend as much as possible. I'd be happy to talk more about how this happens, but here are a few resources: Here's a [great book]( URL_0 ) that explains everything. Here's an [article]( URL_1 ) about when the auction houses got caught price fixing. So laughable because it's what we do every day. It's the way the whole system is set up. We're just a little more savvy now."
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7ai47c | The metal guard on the wheel of a cigarette lighter | Other | explainlikeimfive | {
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"text": [
"It's a child safety feature. It makes it much more difficult for children that somehow get access to the lighter to actually light it."
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7aigke | Why some cities charge employees an "Occupational Privilege Tax"? | Economics | explainlikeimfive | {
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"There are lots of taxes outside income tax so the idea of paying another tax on your earned income isn't a novel idea. Cities can apply taxes for a large variety of reasons and without knowing that specific city your are talking about its difficult to say exactly what their justification for it is, but it's most likely a city with a high demand for space already that they cannot accommodate and this is an effort to control office/housing costs by making the location somewhat less desirable and/or compensate the city services for the high demands of business/homes. Edit: depending on how the tax is structured it may also be an effort to collect tax from employees who live outside the city, therefore pay no taxes for the city services they use 8+ hours a day.",
"I know that one city's council initiated something like this, heavily political, hitting the suburban employees of a huge corporation persuaded to stay using deep tax breaks. So if it's not the corporation, then hit up its privileged workers."
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7aihsz | Why are so many crunchy fruits/vegetables mostly water? Does more water biologically make things crunchy? | Cucumber, celery, lettuce, watermelon, etc. These all have top water-to-mass percentages, like more than 95% water, and they all have a really pronounced crunch. But water is not a crunchy substance, why is it so prevalent in these foods? | Biology | explainlikeimfive | {
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"Not exactly *because* the have water. Partly it's the other way round. They are \"crunchy\" as they have stiff cell walls. That means thay can have a lot of water inside and not collapse under the weight. However you could also say that in order to hold more water, they have to have stiff cell walls so are crunchy.",
"For some vegitables like lettuce and celery, the crunchiness is really the ability to retain water. Water is used to support the plant, to ensure the stalk pushes the leaves into the sun, that the leaves are spread to collect as much sunlight as possible. Once you cut the stalk or leaves and cut off the water supply, it begins to dry out and become soft and lose the crunch. That's why fresh celery is so crisp, but two week old celery gets tough and gummy. For some fruits, crunchiness depends on ripeness. An unripe pear is hard/crunchy and not very tasty. This is to prevent animals from eating the fruit before the seeds have a chance to mature. Once the seeds have become mature, the fruit \"ripens\", the meat becomes soft and more flavorful, which then signals the animals they can eat the fruit and thus the seeds get dispersed. The more ripe the fruit gets, the softer it gets; unlike vegitables, the cell walls inside fruits are set to get soft as it ripens. Fresh watermelon may be crisp, but as it ripens it gets much softer to the point where it is easily mashed, but still have a high water content. Then there are some thick skinned fruits like citrus, grapes, berries, which are never really crunchy but can still have high water content.",
"I think you're falling for a bit of confirmation bias. What is the water content of non crunchy fruits/vegetables? I believe the crunchiness in plants comes from cellulose, which is the primary component of their cell walls. I would doubt there is any correlation/causation between water mass and crunchiness."
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7aiidv | What exactly are the “butterflies” in our stomachs when we are feeling excited or nervous? | Biology | explainlikeimfive | {
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"text": [
"Its a stress response from the adrenal system. Your brain senses some sort of stressful stimulus, and sends a signal through your body. Your adrenal gland produces epinephrine and norepinephrine, which are the chemicals responsible for the adrenaline rush you get in fight or flight situations. The butterflies you feel are just one of your bodies responses to those two chemicals."
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7aiiv3 | Why does doing good things for someone make you feel good in turn? | Biology | explainlikeimfive | {
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"text": [
"Humans are social animals, and most of us like to do good things. When we do good things we get rewarded with a rush of dopamine, which is what makes us feel good. That's the biology of it. The psychology of feeling good has to do with empathy, sympathy, and compassion. We do good because it feels good."
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7ail2e | why would a company ever go public and accept investor money, which they have to pay back indefinitely, over loaning money, which only has to be paid off with interest? | Economics | explainlikeimfive | {
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"Companies only see the money earned by the initial public offering. (IPO) The money exchanged during further trading does not go to the company, nor does money earned from selling stock come from the company. Stock represents a share of ownership of the company, and if you hold enough of it, you get some level of say in the company's operation. Only if the company chooses to buy back the stock does the company pay out to stock holders.",
"The company doesn't have to pay the investors anything. Don't know why you'd think that. The company sells shares at a certain price to raise capital. That's it, they never have to think about loans or paying anything more. They got money for free (except they sold a part of the company)",
"Risk management. When a company decides to expand or enter rapid growth phase it needs a large sum of capital. Banks will be unwilling to loan that kind of money at that level of risk. What will they take as collateral? Next best option is to raise little bit of money from many individuals who believe/bet in company’s success.",
"The first thing to understand is a company is only a group of people (or other companies) that act in concert to make money. It only serves that purpose, not to continue its existence or make money over the long run. Companies need money for a few reasons such as to fund growth, pay off debt or give money to existing share holders for taking risks in the business. There are two main ways to do this: Issue debt or Issue equity. The difference between these two really comes down to this: Debt has mandatory ongoing interest payments and the need to be paid off at some time in the future usually between 3 and 7 years. Equity, does not need to be paid off and doesn't require ongoing interest payments. Companies will usually choose which option to go with based on what it is trying to accomplish and which method best serves that end."
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7ailxt | How come photons travel in waves rather than just going straight? | Physics | explainlikeimfive | {
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"text": [
"Photons don't travel in waves, they are waves. Those waves do travel straight, they just undulate as they do so, no lateral speed lost. So they sort of do go straight, its like if you pulled a spring along behind you car (without friction), the shape of the spring doesn't really affect how fast its moving.",
"It depends on what you are referring to. A single photon (in free space) will go straight. Multiple photons emitted in different directions will appear to be traveling as a wavefront. However, a photon itself is the elementary excitation of the electromagnetic field. That is to say: it's the smallest possible electromagnetic wave. But that elementary wave still travels straight (again, in free space)."
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7aitfj | How did fire arrows not extinguish themselves when they were fired? | Chemistry | explainlikeimfive | {
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"text": [
"because the film team makes sure the wrap is dowsed in gasoline or some other accelerant before they're fired. fire arrows weren't actually used in history. it was made up for tv/movies.",
"They did. Fire arrows in the sense of literally just being a regular arrow but on fire are essentially a myth."
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7aj6ew | What exactly are PACs and SuperPACs. I know the acronym, but I don’t understand what they do. | Economics | explainlikeimfive | {
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"You are getting a lot of bad answers. Literally no answer in this thread (at the time I'm writing this) is completely correct, and most are way off target. First let's separate the concept of a traditional PAC and a SuperPAC. From both a legal and practical standpoint, they are very different things that do things in very different ways. **Traditional PACs** Traditional PACs (Political Action Committees) are committees set-up under rules laid out by the IRS. Many are setup to support candidates for federal office and have to also comply with rules laid out by the FEC. Others are setup to support state or local candidates, and may or may not have to abide by FEC rules and/or rules governing local elections. Focusing just on traditional federal PACs, there are several different varieties. Sometimes they're formed by clubs or organizations with money coming from members. Sometimes they're groups of employees. Other times, they are groups formed by legislators themselves. In all cases, with all traditional federal PACs donations must come from individuals. A corporation cannot, under any circumstances donate to a federally-qualified PAC. When people say that \"Big-Company-X gave to Mr. Smith for Congress\", they actually mean that employees of Big-Company-X gave money to Mr. Smith. Whether it's pooled in an affiliated PAC or individually, all federally qualified donations come from individuals. **Super PACs** Super PACs are a relatively new phenomena that started after the Citizens United SCOTUS ruling. In order to understand how they came about, it's important to look at the background. Several political funding reform bills were created in the 20th century to crack down on the influence of big money in politics. Campaign finance reform has always been a battle of protecting the right to free speech while also limiting the corrupting potential of money. Before Citizens United the law of the land essentially said that only individuals had the right to make contributions to candidates, or engage in any political activity that was considered \"PASO\". PASO activity is anything that **p**romotes, **a**ttacks, **s**upports or **o**pposes a candidate for federal office. Further, there were limits in the amount of money that could be spent to do PASO activity. The legal support for those rules was based on the idea that at a certain point, money spent on PASO activity would create the potential to corrupt a candidate. If I was spending money to help a candidate, the idea was that they might be corrupted by my support. That potential for corruption created the legal basis by which congress had the authority to limit my first amendment right to support a candidate. In Citizens United, there was a group of people who spent a lot of money to make a video that attacked Hillary Clinton. They wanted to release their video, but federal law said that they couldn't spend money to do PASO activity within a certain amount of time leading up to an election. They sued the government in order to allow for them to release their video. They argued that since they were not working directly with any candidate, there was no potential to corrupt. How could they corrupt a candidate (they argued) if the candidate had no say in what they were doing, and they didn't make any asks to the candidate? In a 5-4 ruling, the SCOTUS agreed with that argument. The opinion of the court essentially said that an independent group not directly tied to a candidate that doesn't give directly to a candidate has a right to speech. Further, the supreme court essentially ruled that since such a group has no corrupting potential on a candidate, congress could not limit the amount of money it could raise or spend, nor could congress limit who gives to such a group. From that ruling Super PACs were formed. Unlike traditional PACs (which can give directly to candidates and can coordinate with candidates), Super PACs are limited in what they can do. They can't give money to a candidate. They can't coordinate with a candidate. They can't do and say certain specific things about an election, but they can do certain PASO activity. In exchange for those limits on speech and coordination, Super PACs can raise and spend unlimited money from a much wider variety of donors. Contrary to popular belief, Super PACs must disclose the money they raise and spend (for the most part). There are other dark money committees that don't have to disclose their finances for certain activity, but they aren't Super PACs."
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7aj959 | Why are video games almost always rated between 6-10/10 with 6 being considered a terrible game but movies and tv shows seem to be rated between 1-10/10 with 6 being decent. | Technology | explainlikeimfive | {
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"Game journalism is very different compared to movie reviews. Most game journalists will not even finish a game before putting out initial impression reviews. Movies are only 1-3 hours long. Many games can be 60+ hours and the competition to get your review out as soon as possible is real. Like you see with the movie industry with many critics, the companies who produce the content have relationships and deals with the game reviewers. Big developers often give their reviewers perks like advance copies of big titles. Reviewers want to maintain their good relationship to keep getting these perks, and AAA publishers know that 1 bad review could seriously harm their multimillion dollar investment into a product. Part of it is probably just a different culture. That's what reviewers are used to doing and used to seeing, as lame of an excuse as that is. I also personally believe most people don't really know what goes into making a game good in terms of level design, music, pacing, animation, level of polish in all those details, ect. so it's difficult for many people to be displeased with a game when they don't really know what makes a game good or bad. Also, anchoring.",
"Because a lot of education systems see 70% as a bare passing grade. So people grow up with that mindset. You see a 5/10 game and think \"oh that must be horrible\", even though that should be just average. That's one thing I like about Destructoid and Jim Sterling's review scale, it actually reviews games out of ten. A 7 is still a good score BotW fans.",
"The ratings mean the same thing: roughly, \"watcheable\" or \"playable.\" The difference is watcheable means you spend 30 minutes to 2 hours of your life getting an average experience while playeable means you spend 30 to sixty hours getting an average experience. Is not that the ratings mean different things, its that your time has value and if someone offered you 30 hours of an okay experience, you'd probably take a hard pass.",
"Also to consider there are many more factors to include in a game’s review. You have graphics, frame rate, gameplay, controls, UI, replayability, difficulty, load times, multiplayer, balancing. On a tv show or a movie, there isn’t any of that stuff to consider. So if a game comes out with a great storyline and campaign, but the frame rate is lousy, controls are awkward and doesn’t give the gamer the ability to modify them, game is too easy, and offers nothing after beating it, that could bring it down to a 7 and with those negatives, could be considered bad. Also must consider the cost. A movie is $13-15 bucks and a couple of hours. If it sucks it’s not as big of a letdown if you dropped $60 and 25 hours into a game."
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7aknuw | why is the existence of an indefinite electromagnetic field different from the presence of a luminiferous ether? | If light is a propagation of energy in the electromagnetic field, how is the behavior of a electromagnetic field different than the behavior of the luminiferous ether that was disproven in the Michelson-Morley experiment? | Physics | explainlikeimfive | {
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"text": [
"It has to do with frames of reference. The ether was meant to serve as a sort of absolute reference point that every thing moved relative to. The electromagnetic field is not an absolute frame of reference. We choose the frame of reference for the part of the field that we care about and calculate things relative to whatever that is."
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7aky9q | Do neurotransmitters remain intact when an organism dies? If so, could eating certain meats contribute to our feelings and emotions? | Biology | explainlikeimfive | {
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"text": [
"Kind of, but not really more than any other foods. Most neurotransmitters would be broken down by enzymes in the stomach. But amino acids, such as tryptophan, are necessary for the body to produce neurotransmitters such as serotonin, and you can get those from eating meats. But you aren't going to feel your hamburger's happiness."
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7al2hu | Why do we stop growing? | what tells our bodies to stop growing, instead of being 6 foot tall at 60 years old, why not 12 foot tall etc/ | Biology | explainlikeimfive | {
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"Our levels of growth hormones as children are regulated by the pituitary gland. As to why it's at 6 feet tall, it has to do with our bone density, skeletal structure, and other biomechanical things regarding our circulatory system and internal organs: our hearts work optimally for veins/arteries in people about 5-6 feet tall. Much more, and the heart has to work harder to get blood to our extremities. This is in part what caused the death of Andre the Giant. Gigantism is caused by a tumor on the pituitary gland that blocks the incoming receptors of HGH and causes it to produce and release excessive amounts of the hormone, which super-charges growth. This in turn leads to lots of health issues. Most people with full blown gigantism end up having relatively early deaths, as in dying in their 40s and 50s.",
"Bigger isn't always better; bigger organisms require more energy, and resources in biological systems aren't infinite. So our bodies only grow when they need to. Bodies grow for lots of reasons, but cheifly in response to hormone production. Once a person reaches a certain size/age, their body will stop secreting the hormones/secrete less of them/alter them, and parts of the body that were adding height will stop doimg so. Once the growth regions of your bones (especially the ones involved in height, like your leg bones) close up for business, there's basically no reopening them. If you want more details on the specifics, check out Crash Course videos on Youtube, or similar (this is explain like I'm five so I don't wanna overdo it lol) Additionally, after a certain point, some cell lines are differentiated to the point that can't be reversed. This means they have \"decided\" what they want to be, and then, although they can keep on dividing, they can't divide and go on to be a different kind of cell. This is why stem cell research matters; a stem cell could grow up to be a retinal cell, or a brain cell, or a liver cell, or anything. A muscle cell can only be a muscle cell. Skin cells actually have slightly flexible stem lines, so they are good at repairing. This doesn't relate to your question about height, but it explains why we can't just grow back our arm after one gets cut off."
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7al3ec | Why is the inside of a refrigerator cold, but the sides hot? | Physics | explainlikeimfive | {
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"Refrigerators cool your food by pumping heat energy out of the inside of the fridge. They then dump that heat into the air around the outside of the fridge, typically from the back of the unit. As long as the fridge has sufficient insulation, the heat doesn't really get back in.",
"Refrigerators and air conditioners work by moving heat from one area to another. While an air conditioner moves it from indoors to outdoors, a refrigerator moves it from inside to the outside. Some use the sides to dissipate the heat. Others use the rear or bottom.",
"This is like asking why the space on one side of the broom is clean and the other side is dusty. The broom has moved the dust. That is it's purpose. Similarly, the fridge has moved the heat. That is its purpose.",
"When you compress a gas, it heats up. When you expand it, it cools down. But this doesn't change the energy in it. Your fridge has some gas in it, like freon. It expands that gas until it's colder than the inside of the fridge and pumps it inside. Heat flows from your food into the freon, removing energy from the food and adding it to the freon. Then the fridge pumps the freon out and compresses it. Now it's hotter than the room, and it can cool off, warming your room. That makes the inside of the fridge cold and the outside warm."
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7al6co | Noise Isolating headphones vs Noise Cancelling | I see lots of headphones that are Noise Cancelling or Noise Isolating. What's the difference and how do they work? | Technology | explainlikeimfive | {
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"noise isolating. consider this ear plugs that have earbuds in them. THey block outside noise by providing a noise reducing barrier. In fact my isolation earbuds are so good I use them as Earplugs when using a circular saw or mowing the lawn. NO music and not even plugged in. Noise Cancelling Headphones that essentially listen to ambient noise and produce an opposite sound wave to blank out the unwanted sound. Fill your bathtub with water. Drop two rocks into the tub one at each end. When the waves collide you will see a spot where the water seems calm because the waves are cancelling each other out. Noise cancelling headphones produce this negative wave by listening in to the outside noise and producing the opposite wave to cancel out the wave just like in the water.",
"Noise isolating headphones block sound. Noise canceling headphones effectively add anti-sound. Anti-sound is identical to the original sound, just out of sync by half a wavelength. A sound is just a pattern of high and low pressure air waves. By adding another sound that has high pressure when the original one has low pressure and vice versa, you cancel out the sound. Noise canceling headphones generally require their own batteries in order to analyze sounds and make the corresponding anti-sounds. Noise isolating headphones just need to cover your ear with something that doesn't transmit sound very well.",
"Noise isolating is like using insulation to keep your house warm. Noise canceling is like adding a heat source to the house.",
"ELI5: can noise cancelling headphones mess with my hearing? I mean, that signal being pushed into my ears over time. Especially as someone who suffers from tinnitus.",
"Imagine you're standing on the long rope bridge at the playground and Jimmy is on one side of the bridge shaking it up and down. When he shakes the bridge like that, you move up and down, and that's kind of how sound works. For a noise isolating headphone, imagine that we lay down a bunch of heavy blankets all along the bridge to weigh it down. Jimmy's still shaking the bridge up and down just as much as before, but you don't move around quite as much. That's like how a noise isolating headphone tries to quiet down the sound waves that are coming to your ear. For a noise cancelling headphone, imagine that I'm standing on the ground in between you and Jimmy. While he's shaking the bridge, every time he lifts the bridge I pull down on it, and every time he pushes down on the bridge I lift up on it. The better I'm able to perfectly counteract Jimmy's shaking, the more it's like you don't feel any shaking at all. That's like how a noise cancelling headphone tries to cancel out the sound waves that are coming to your ear. Please don't hang out with Jimmy at recess anymore.",
"\"Noise isolating\" headphones are like earplugs with headphones in front. The sound outside your ears hits the earplugs first, which makes it quieter. Since the headphones are on the ear side of the earplugs, they don't have to be as noisy for you to hear them over the noise the earplugs are blocking. \"Noise cancelling\" headphones use a neat trick to make sound \"disappear\". For every sound, there's an \"opposite\" sound. If both sounds happen at the same time, you \"hear\" no sound. So \"noise cancelling\" headphones have a microphone and a computer. They constantly and quickly sample the noise around you, create the \"opposite\" noise, then add that noise to the music you're hearing. To your brain, this sounds like \"I am in a quiet room and this music is playing\". Because of this, \"noise cancelling\" headphones need batteries even if they have a wire, because the computer and the microphone need a little bit of power to work. They tend to be fairly big and bulky if they work well. Since \"noise isolating\" headphones are just earplugs, they can be smaller and don't need batteries to work. Unless they're wireless, but that's unrelated.",
"Lots of good explanations here. I'll just add more info as a headphone collector. Noise cancelling (also known as ANC/active noise cancelling) headphones generally sound worse because of the \"anti-sound\" that they make. They also produce nauseating sensation that can make you feel fatigued. If you don't need to deal with constant and regular noise (e.g. engine noise), avoid ANC headphones.",
"Noise isolation is just insulation. Noise cancelling uses a tiny microphone to \"listen\" to the incoming ambient noises and cancel them out with destructive wave interference before they reach your ear.",
"The noise isolation ones are passive, like the ones you find on construction zone. They isolate you from the environment by blocking the exterior sound from reaching your ear. The noise cancellation one are active. They usually have one or several microphones to listen for the exterior sounds and cancel them by sending the same sound \"reversed\". Imagine you meet your boss and shake hands. You are both sounds and the eardrum is your handshake. You want to have a firm handshake (no noise or no movement of the eardrum). To do that you need to kinda apply the reversed hand movement of your boss. In this way, you will both move your arms but the handshake will have a fixed position."
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7al7hu | How is the wind capable of making 20 m high waves? | I understand how wind can make waves but how can it make huge waves that moves very slowly? Like wouldn't the wind just go past the waves long before it reaches that enormous amount of energy? | Physics | explainlikeimfive | {
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"The wind blows consistently over a very long distance of ocean. It isn't one single strong gust which blows a wave up, but a sustained force that puts lots of energy into the wave.",
"At first the ripples from the wind would be completely random, the larger ripples, or often when 2 or 3 intersect, and get to be higher than the waves around them, they have a higher windage - or area \"in\" the wind, putting more energy into this wave. Next - waves, are, well waves, meaning they really are an oscillation of energy. So over time as more energy in transferred from the wind to the face of the wave, the water forms a more regular pattern, and multiple waves are generated, as part of a more regular oscillation. Similar to if you touch the surface of water, you can't make just ONE wave, even if you try to construct an experiment to make a single wave, the energy get dissipated into multiple waves. They - actually do not move that slowly, the speed is the same as smaller ones, as the waves get bigger their period gets longer, but the speed of propagation is essentially the same.",
"20 m waves are rare, and are usually formed under special conditions. Waves of that size in California f.ex are usually formed by storms off the coast of Alaska. A forceful storm creates significant waves with a high frequency (distance between each wave). As the waves first form they will create a current inside each wave which amplifies the effect of the wind. Imagine a barrel pushed down the street by the wind - the rotation of the barrel makes it easier for the wind to make it go even faster. The high frequency is also important as waves can work against each other. Lastly, when waves that have built up a lot of energy approach land they will be affected by the bottom of the sea. If the sea bottom is a long, gradually increasing incline (like the Atlantic side of the US) then the sea bottom will remove the power of the wave - constant resistance over many miles. In surf spots in Hawaii and Australia the sea bottom rises quickly and the first mass that impacts the waves is often a large coral reef. So the wave is coming in at full speed, the space for the water is suddenly very restricted and it has nowhere to go except upward. So you get really tall waves. The places with the largest waves recorded - a handful of places that \"compete\" for the largest waves recorded - all have similar features. These features are: a rapid incline followed by a bank or reef, coinciding with a funnel shape of land - these factors jointly force the waves upward and you get gigantic waves. For an example of the effect [here is a video of big wave surfers in Nazare, Portugal]( URL_0 )"
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7al9x6 | How is energy reserved? | Say if I clap my hands, where does the energy go that I used to bring my hands up and push them together? If the energy goes into making heat and sound, then once the heat has cooled and the sound has gone, where then does it go? | Physics | explainlikeimfive | {
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"> then once the heat has cooled and the sound has gone, where then does it go? Heat doesn't cool, it dissipates. It spreads out so a particular area cools but there is still the same amount of heat out there in total. The sound is dampened into heat as well. That heat will stay on Earth until it eventually is radiated away into space. But even in space it keeps on going.",
"Ok, so you know how when you fart, it smells pretty bad at first, but then goes away slowly? The fart molecules didn't get destroyed or anything. They just started spreading out into the air, and eventually they were so spread out, so dilluted, that you couldn't smell them anymore. Like if you dumped Kool Aid into the ocean, it wouldn't become fruit punch; the molecules would spread out to the point they'd be imperceptible. The idea that concentrations of stuff(fart smells, kool aid particles, etc) will naturally shift until concentration is equal is key. Heat behaves more or less the same way. It \"wants\" to spread out until it is equally hot everywhere in the area it can reach. You stop feeling it because it has dissipated, but it's still there. You know how a down coat is warm, but, say, a suit of armor wouldn't be? The tiny fluff of the down feathers creates tiny pockets of trapped air, thus trapping the heat. In your hand clapping example, there is less to stop that heat from escaping, so it naturally goes to areas of less heat until it has dissipated to the point that you can't feel it any more. It is also relevant that heat energy isn't really available to living things to do the job of living. It is effectively \"gone\" to us in the sense that it can't often be used, but it is still physically there."
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7amw6w | Why were there naval battles in the American Civil War? | Other | explainlikeimfive | {
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"The Union blockaded Southern ports to stop them from receiving goods from international trade that could support their economy or war effort. The naval battles were around this blockade."
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7amy7d | why do foods taste different once they've been melted. For example: chocolate, cheese etc. | Chemistry | explainlikeimfive | {
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"Because the taste receptor TRPM5 (which picks up sweet, bitter and umami tastes) sends a stronger electrical signal to the brain when food is warmer."
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7an0uy | Since there is no up or down in space, how do we know that Uranus’ rotation is tilted? | Physics | explainlikeimfive | {
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"Its tilted relative to the orbital plane. Most planets rotate somewhat perpendicular to their plane on orbit around the sun. Uranus on the other hand is weird and its poles basically face the sun.",
"\"tilted\", just like up, down, speed, ect, is a relative term. In this case it is relative to its orbital plane. Just as earth is tilted (but much less so than uranus) relative to its orbital plane and is the reason we have seasons",
"Put your right fist on a table, with the thumb sticking up, like you're giving a \"thumbs up\" to your computer screen. Uncurl and curl your fingers again, and notice how your fingers move when you curl them in. If you look straight down, with your thumb pointing towards your eye (don't poke yourself!) Your fingers will be moving counter-clockwise when you curl them. This is called the \"Right hand rule\" (it doesn't work with your left hand, so if you need more planets, find some friends to help). When a planet is rotating, put your thumb along the axis of rotation so that when you curl your fingers they move in the same direction as the planet rotates. If you've done it correctly, the direction your thumb points is called \"north\". If the table is the solar system with the sun is in the middle, and your hand-planets are rotating around the sun along the surface of the table, most planets will have the thumb pointing up-ish (earth's axis is 23 degrees off, but it's close enough for our purposes). There are two exceptions: Uranus would have a thumb pointing sideways and Venus would have a thumb pointing down. We use the orbital plane of the earth (the surface of the table, in our example) to help tell us what \"flat\" is, and then we can compare angles against this flat part."
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7anb8i | The interaction between unemployment and wage stagnation. What pressures are acting to keep wages flat? | In theory, it seems that low unemployment would drive up wages as companies are competing harder to find talent. What other pressures are acting on the job market to keep wage growth flat despite really low unemployment and an economy that’s growing? | Economics | explainlikeimfive | {
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"Automation and international labor (outsourcing, offshore manufacturing, etc.) are two huge pressure-relief valves that open up whenever wages start to climb. An employer will quickly say \"why pay higher wages, when for that price I could have a computer/robot/machine customized to do this job, or have it done in a cheaper country?\" The latter is extra scary since that cheaper country may also have lower environmental protections and labor protections. The former is extra scary because automation, once figured out, is easily copied in large numbers and just gets cheaper.",
"Employers taking advantage of workers job insecurity, the non existence worker organization. The collusion of wall street and Washington to even further reduce the rights of workers. I'd recommend Richard wolf for more information",
"I'm no professional but I am employed, after having looked for a job for 9 months. To me, those in a similar situation don't care about z raise - they want stability. The reality is, if the new guy pushes for a raise, he is easily replaced. Even those with seniority understand how shaky their position is",
"The low interest rate and low inflation also keeps wages down. Low inflation or deflation means there is no opportunity loss in holding on to your savings. Inflation tends to increase consumer demand, and because of inflation they get comparable wage increases - often overlooking the fact that home value are also rising and personal debt is decreasing in real value. Which increases further the disposable income, and drives demand growth, and feeds the inflation and feeds the wages."
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7and65 | Why does ice stick to the bottom of the glass? | Chemistry | explainlikeimfive | {
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"There is an adhesive force between the ice cube and the glass mediated by a thin layer of water. Basically, when any two things get close enough together, there are both attractive and repulsive electrostatic forces that occur, called Van der Waals interactions. These forces can overcome gravity in certain situations, like when a gecko crawls on the ceiling. Water is a permanent dipole, which means the molecules act kind of like tiny magnets. It sticks to itself very well (coheres) and sticks to other things pretty well (adheres) depending on their surface chemistry. If your ice cube is smooth and flat enough that a large, thin film of water can adhere it to the glass, it will stick. If it's light enough, it can probably hang vertically from the bottom of the glass."
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7anktu | How do smoke signals work? | How the divisions in smoke clouds are made, and what is the code to read them? | Other | explainlikeimfive | {
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"The one drawback of using smoke signals is that the enemy could also see them. For this reason, there wasn't a set code for transmissions, and each tribe had its own system. The meaning of the message was predetermined and only known to the sender and receiver of the signal. A tribe might send a message that the enemy was near or that sickness had fallen over the camp. They would also commonly use the signals to announce the outcome of battle or to call for reinforcements. In order to send signals over greater distances, tribes would set up a chain of fires to relay the message from one to the next."
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7anq7b | Isn't all soap anti-bacterial? | Chemistry | explainlikeimfive | {
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"Both regular soap & anti-bacterial soap kill germs or simply help wash them away. One of the benefits of regular soap is that it preserves healthy bacteria on your hands. Like the rest of our bodies, our hands have healthy bacteria that we need for various bodily functions. You might know that consuming too many pills might require you to need a fecal transplant because the pills can kill the good bacteria you need. Anti-bacterial soap kills germs, yes, as does regular soap, but also is anti-bacterial in nature so it kills the healthy, necessary bacteria on your hands as well. Not a disclaimer against anti-bacterial soap because you'd have to use it a LOT for it to be an issue, but those are the differences between them."
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7aoc1x | How does a loading bar work? | When a game or a video is loading up, most of the times we can see a bar being filled until it is completely full. How does it work? I mean, is it just an "image" being multiplied several times? (Obviously I know there's a bunch of codes behind it) | Technology | explainlikeimfive | {
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"It can be done in many ways. Having multiple whole images of of the loading bar at various percentages is common. But just as common is generating it programmatically - describing it, not as whole lot of pixels, but as a drawing - a rectangle with rounded corners, and a thick line with sharp corners for the progress bar. Another way is having two images or animations, one of the full progress bar, one of the empty, layering the full one over the empty one, and only revealing the leftmost part of the full one, progressively revealing more of it as time progresses. More interesting is the logic for guessing how far through a procedure you are. Parts of the process will go faster than others, and some of it will be unpredictable. For instance, when Windows copies files, it only knows the number of files it has. If the first files were large, it will predict that this will take days, until it hits the lots of short files at the end and if finishes quickly. Now, you can fix this by checking the sizes of all those files when you start, but that takes lots of time. So you have to trade off better accuracy in your estimate against time taken."
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7aoikc | what's the differences between anti-bacterial, anti-septic, anti-germ, and anti-microbial? | Biology | explainlikeimfive | {
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"Anti-bacterial - Kills bacteria or otherwise messes with them in some way (e.g. prevents them reproducing). Antiseptic/anti-germ/anti-microbial - Kills bacteria, viruses, likely also fungi and parasites like protozoa. This is stuff like strong alcohol (60-70%), bleach, chlorhexidine, iodine, etc. which will kill most things. May or may not work on particularly hardly things like prions or bacterial spores."
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7aoke6 | Why are interest rates so low for me if I deposit money, but so high for students who lend it? | Economics | explainlikeimfive | {
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"Because you're a very small fry and the bank makes almost no money on your deposit. And you want *services*, like ATM fee forgiveness, customer service, cash back credit cards, and just putting up with your smell is going to cost you half a percent! People with very large accounts can get 'OK' interest rates on a deposit - up to 4% for multi-millionaires who decide to keep millions in cash on hand. Because multi-millions makes a lot more for the bank than small fry's do and they don't require much more in the way of *services*. And students get juicy bank anal lovin' because they are risks. The *real* risk is just about zero because the government buys the loans, but they like to pretend students are a big risk to lend money to. So they jack up the rate to pay for the students who can't ever find good jobs, sell the loans off to the government to eliminate the risk, and laugh all the way to the bank, only they are the bank, so they are just enjoying a hearty laugh at how they forced you to work through the motherhood years and now you're a haggard old crone and can't afford a 3rd mortgage to coax one of your rotten eggs into becoming a baby."
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7aoopu | If the Big Bang happened +/- 13.5B years ago, and if matter - and thus the universe - has been expanding outward ever since, shouldn’t there be a massive void in the center of the universe? | Other | explainlikeimfive | {
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"This is a common misconception. There is no center of the universe, the Big Bang happened everywhere at once. The point is that *everywhere was very close together.* The entire universe was basically in the same place; not that all matter was in the same location, all **locations** were close together. So the universe expanding is all locations becoming more distant, not mass itself traveling through space. The mass might as well be stationary.",
"The term \"Big Bang\" can be misleading for this very reason. It can give the impression that the BB was like a conventional explosion, which is inaccurate. A conventional explosion occurs within space-time and local matter is forced outwards. The BB was the expansion of space-time itself. The expansion isn't just happening at the center; it's happening between every point in space. Therefore, the [cosmic microwave background radiation (CMB)]( URL_0 ) shows a very (but not absolute) even distribution throughout the observable universe. Tiny fluctuations that occurred during inflation resulted in the formation of galaxies, which makes the universe appear lumpy on relatively local scales, though the density fluctuations become very small on the cosmic scale.",
"The universe expands outwards from every point. Its almost like the universe is the surface of a balloon and its being inflated. There is the same amount of matter, except in this case its infinite matter, the matter just spreads further and further apart.",
"The matter hasn't been expanding away from a single specific point. Every bit of space in the universe is expanding away from every other point. The Big Bang was not an \"explosion\" in the usual sense. Imagine an infinite rubber sheet with a 1\" grid on it that represents the dense universe before the Big Bang. Now, stretch it out so that the grid lines are now 2\" apart from one another.",
"Instead of thinking of it as a ball of matter exploded outwards, imagine instead that the space between each atom in that ball of matter expanded. As its understood, there isn't anything that the matter could have \"exploded into\", it could only have the space between it expand. Think about zooming in on a graph on a calculator. The space between the lines appears to be further a part, but that's not to say the lines actually separated. It's not a perfect metaphor but I hope it helps a bit",
"its not that everything shot out from the center of the universe, its that everything shot away from everything else. So matter that started at the center (even though there isn't really a center according to the common understanding but its easier to visualize if we pretend there is) would not be moving at all. Matter that started right next to it would be moving very slowly, and the velocity would increase as you move further away. Except because there is no actual center of the universe, you could arbitrarily define any point to be the center for the purpose of mathematics (for example where we are observing from) and this relationship would always hold true, with everything moving away from you at an increasing velocity with distance. This relationship was found through direct observation and is described by the Hubble constant.",
"The big bang was not an explosion **in** space, but rather an explosion **of** space. The only \"center\" of the universe that one can define is the center of the observable universe, which by definition is always centered on the observer. The greater universe may be and may have always been infinite in extent. We don't know. As such, it can't necessarily get any larger, but it is expanding in that every point in the universe is getting further away from every other point. This is, in fact, why there is such a thing as an \"observable\" universe at all. The further away you get from the observer, the faster space at that distance is expanding away from you. At a distance of 46 billion light years, space is expanding away at the speed of light, so any events occurring beyond that distance will never have any causal relationship to events at the observer's location. Anything beyond effectively does not exist, although we know it is there, we can't \"see\" beyond that boundary."
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7aovex | why aren't video game graphics as good as current animated features, like Zootopia? | Other | explainlikeimfive | {
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"Movie graphics can be created over a long time and polished for release while game graphics are created on the spot. Movies are also rendered in giant computing farms while games run on personal hardware. It is the difference between needing to make a video frame every few hours vs 60 per second.",
"A movie doesn’t have to deal with changing inputs and scenarios like a video game does. It all has to do with how fast the computer processing the game is capable of loading the environment, other characters etc.",
"Think about what is necessary for good graphics. A computer must run a specific amount of calculations to render whatever frames it needs to. The quality of the graphics is determined by the quality of the frames, and the speed at which they are generated. In animated movies, the calculations are done at Disney supercomputers and over the course of many weeks. Contrarily, the graphics for video games are generated on your not-so-great home computer in an instant."
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7aozis | How does shaking up a soda increase the pressure inside the bottle? | Obviously it’s science, but I can’t see how it happens because the carbonation is already in the container with the soda. Even if it separates, the volume should be the same... Right? | Chemistry | explainlikeimfive | {
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"It's because the carbonation actually has two different states, a gas and an acid. When you take carbon dioxide gas and put it under pressure next to a liquid like water or soda or cider or beer, that CO2 actually reacts with the water to form a fairly unstable acid called \"carbonic acid\". It's unstable enough that as soon as the pressure goes away, the carbonic acid molecules start breaking back down into water and carbon dioxide molecules. Open a carbonated beverage container and over a little while the breakdown transforms all of the carbonic acid back to carbon dioxide, the carbon dioxide bubbles off, and the container of liquid goes flat. And a shock makes the instability a lot worse. If you increase the instability by pouring a just-opened beverage from on high, the shock causes the carbonic acid to rapidly break down, which is why pouring soda too fast causes a huge foam-up. Ditto when you tap a glass of beer with another glass of beer. And if you shake the bottle or can of soda without opening it, you're breaking a whole bunch of carbonic acid into carbon dioxide - a gas - and it really increases the pressure in the can because all that CO2 can't leave. But wait a while, and the pressure will force the CO2 to form back into carbonic acid... and the pressure will reduce so it won't blow up when you open it."
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7ap1k2 | How do decongestants work? And do they affect the way our body fights infection or illness? | I've got probably the worst cold of my life with some rather unpleasant, if not downright severe, sinus pressure. Mucinex is my decongestant of choice and when taking it just now I wondered how exactly it does what it does. And if, while removing mucus from my sinuses, does it also remove any functionality of my immune system? Would I shake the cold quicker if I were to tough it out? Surely the mucis is there for a reason? Thanks in advance :) | Biology | explainlikeimfive | {
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"Plain Mucinex is not a decongestant, it is an expectorant. Look on the back of the box at the ingredients. If only guafenisen is listed you have plain Mucinex. What that does is thins the mucus in your lungs so that it is easier to cough up. There is some question about how effective it is over just drinking plenty of water, but it isn't going to hurt you. If pseudoephedrine is listed as well, that is the decongestant. If not go to a pharmacy and pick some up. It works by making your body constrict the blood vessels in the nasal region which reduces inflammation and how much mucus is produced. Dextromethorphan may be another ingredient. That is a drug that helps stops coughing (antitussive). None of this stuff will make your cold longer. There is no reason to tough out a cold"
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7ap6nc | When an employer makes you take a personality assessment test, what are they really measuring? | Other | explainlikeimfive | {
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"> And how serious is a company evaluating you based on the results you get? Are you smart enough to pretend to be a functional human. That's it really. The answers should, generally speaking, be obvious. The tests are all garbage and none of them actually measure anything worthwhile other than whether or not you're smart enough to lie about the amount of stealing you're going to do.",
"There are various such tests. They can screen for mental illness, dishonesty, or aptitude for a particular kind of job.",
"Are you introverted or extroverted, do you work with a team well, do you have consistency in your answers"
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7ap98k | Why is it that you can develop things such as allergies & asthma later in life? | Biology | explainlikeimfive | {
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"... and why do some people \"grow out of\" allergies? For example, I used to be allergic to chicken eggs. Especially under cooked chicken eggs. But, I no longer have problems eating them. I also no longer get chocked up and I also no longer get stomach pains and or gas after eating them.",
"I have heard of people growing out of those things, but not of developing them later in life. My guess is that you were exposed to something you were always allergic to but weren't around it enough to know, and which perhaps you interpreted as being allergic to several things, and that allergy also cause asthma like symptoms. Personally I am allergic to cats but didn't know it until I grew up and moved to a place that didn't have cats. I had always been pretty sure I was alergic to something but the doctors decided it was just dust bothering me. Then when I moved out the asthma I had all my life seemingly went away, because it had always been exacerbated by the allergy.",
"The real answer is, we dont know. People get sensitized and desensitized to a variety of particulate environmental stimuli. If the immune system recognizes something you encounter as a threat, then it mounts a response, which you see in the form of an allergic reaction (ie histamine release from monocytes). Asthma's pathophysiology is very similar, but involves the Lungs and has to do with broncoconstriction, mucous production and increased heart rate... which is relieved when the relevant receptors which induce inflammation are blocked when you take your blue inhaler. Asthma, Rhinits and eczema are all related and are called \"atopic\" conditions, which can be thought of as an unnecessary response to a harmless substance. Children who grow up in a super clean environment do not get exposed to as many allergens so when they do , their naiive immune system mounts a response. Even when pregnant, exposure to certain allergens has been shown to reduce the incidence of atopy in the child. (ie pregnant mothers with dogs have children who are less likely to have an atopic condition) This is called the hygiene hypothesis. However, the hypothesis has little to do with the development of allergies in later life. TlDr: We dont know why people get allergies in later life."
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7apd9i | the sinking feeling in your stomach.... | Biology | explainlikeimfive | {
"a_id": [
"dpbtuqt"
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"text": [
"It is due mainly to the stimulation of the Vagus Nerve, though it is not fully known. This thick cranial nerve originates from the brain and travels downward to the mid abdominal cavity. It branches around the relative areas of the stomach and heart. And is stimulated with emotional and stress responses. This is the reason there is a \"gut feeling\" or a \"feeling in my heart\" or if your heart/stomach drops, the Vagus Nerve."
],
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6
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|
7apgxj | Why is it more comfortable to lay on a certain side? | Other | explainlikeimfive | {
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"dpbwavs"
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"text": [
"Something to do with the position of your stomach, aparently you're more likely to get acid reflux laying on one side compared to the other."
],
"score": [
4
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7aq0l1 | Why do cinema screens get slightly wider just before the movie starts? | Other | explainlikeimfive | {
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"text": [
"It's simply to accommodate the aspect ratio of whatever is being shown. Some previews or ads might be narrower, while some movies on release use very wide aspect ratios of e.g. 2.35:1.",
"Films aren't all recorded in the same aspect ratio. Unlike a monitor, a film projector can project in multiple aspect ratios. Before the movie starts, they adjust the curtains to make whatever aspect ratio the film ends up being in look \"natural\" and fill the whole scree."
],
"score": [
3,
3
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7aq4sx | CPU Overclock | I have just bought a new laptop. The Dell Inspiron 7577 i7-7700 3,8 Ghz laptop. however when I looked at the specs I only had 2,8Ghz. When I looked further I saw that it was 3,8Ghz overclocked. But I have no idea what I mean. I searched google and they say it is maxing out the potention of the pc. But never do they say how, or they give a professional 4 page essay. Thats why I thought I would ask reddit. | Technology | explainlikeimfive | {
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"text": [
"It's probably an automatic overclocking for when the computer is subject to heavy operation. If you play a demanding game, the computer can \"put the pedal to the metal\" for you to make the game run smoother. This will however require more power which drains the battery faster and makes more heat. Computers will even clock down if you're not running any demanding applications as a power saving feature. BIOS overclocking is however rather unusual on consumer laptops due to the cooling systems having to trade efficiency for weight and laptop makers liking to squeeze your wallet for a tiny bit more speed. As for an ELI5 on overclocking itself: The \"clock\" on the processor is a bit like a metronome. It ticks at a certain beat, supervising the rhythm of which the processor works at. Overclocking essentially means ramping up the \"beats per minute\" of the processor.",
"Overclocking is the purposeful setting of hardware registers to operate beyond manufacturers recommended or \"stock\" settings. Results vary extremely wide based on a dozen or so factors, half of which are environmental. In the case of your laptop, there is likely a \"turbo boost\" option in the bios to unlock that extra ghz. Laptops are generally poorly suited to overclocking as they lack good aftermarket cooling."
],
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6,
3
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7aq5ry | Why do different races look so distinct from each other? | Biology | explainlikeimfive | {
"a_id": [
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"text": [
"In some areas of the planet, people who could run fast and to catch their food were more likely to survive, and therefore breed, and therefore make more people that looked like them. In other places, people with pale skin were able to synthesise more vitamin D in areas of low sunlight, so they were more likely to survive and breed and make more people that looked like them. Rinse and repeat for hundreds of thousands of years and you have very different looking people around the world.",
"They don't, which is why race is purely a cultural thing. It exists on a gradient and there is no clear, distinct line you can draw that everyone agrees on to group people based on it.",
"Circular question based on a false premise. Even people of exactly the same 'race' (however defined) look distinct from each other."
],
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11,
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|
7aqb4e | How fiber cabling is faster than standard cabling. | Technology | explainlikeimfive | {
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"text": [
"Standard cable uses copper wiring to send electric pulses that send data from one place to another. It's fast, near instantaneous for simple signals like telephony and SD cable. Fiber-optic cable uses mirrored flexible tubes to divert pulses of light, instead of electrons. Using fiber-optic cable, you can send different frequencies of light at the same time, increasing the number of channels available and increasing the speed in which information is transferred. This results in higher quality video, more variety of cable channels, faster internet, and clearer calls.",
"Individual signals inside both fiber and electrical cables do travel at similar speeds. But you can send way more signals down a fiber cable at the same time as you can an electrical cable. Think of each cable as a multi-lane road. Electrical cable is like a 5-lane highway. Fiber cable is like a 200 lane highway. So cars on both highway travel at 65 mph, but on the fiber highway you can send way more cars. If you're trying to send a bunch of people from A to B, each car load of people will get there at the same speed, but you'll get everyone from A to B in less overall time on the fiber highway than you will on the electrical highway because you can send way more carloads at the same time."
],
"score": [
18,
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|
7aqhbw | What qualifies as the "middle class"? | Economics | explainlikeimfive | {
"a_id": [
"dpbzvi2"
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"text": [
"Middle class is more a matter of how you feel about your financial situation. The poor know they are poor. They know because they can't afford things and have to make sacrifices in life in order to live. The rich know they are rich. They are beyond concerns of debt and spending limits. These are the people who never have to sacrifice. They simply buy whatever takes their fancy. The middle class is everyone in between. People who have things, can buy things, but still have to budget and worry about how much their debt is balanced against their income. This is why 200k and even 400k people consider themselves middle class. They still have huge mortgages and car loans, just for bigger and better houses and cars. They are trying to live within their means even if they have greater means. They still stress out because a few hundred dollars could mean they're no longer making the mortgage on the $500,000 house. So in the most simple terms I can think of: Can you afford a mortgage? Then you're middle class. If you cannot, you're poor. If you bought the house in cash, you're rich."
],
"score": [
11
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|
7aqhcd | Why do certain medicines (like nusinersen) used to treat rare and life-threatening conditions have exorbitant prices to them (say $125,000 per dose) making them inaccessible to people that need them to live? | Economics | explainlikeimfive | {
"a_id": [
"dpbzjfb"
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"text": [
"In the USA, companies are free to invent new medicines at their own expense. These are their property, and they are free to keep them secret, or to give them away, or to offer them for sale at any price they choose."
],
"score": [
5
],
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|
7aqiix | How come in plenty of markets, it seems like we always end up with a handful of major players, but for cars, you still have dozens of brands from many countries that compete against each other? | Economics | explainlikeimfive | {
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"text": [
"Excluding specialty and high-end companies, there aren't really dozens of independent car brands. Most of them are owned by a few [large conglomerates]( URL_0 ). Volkswagen, GM, and FCA all own 10 or more brands. And there are a lot of other partial ownerships. FCA owns 90% of Ferrari. Nissan owns 34% of Mitsubishi and Renault owns 43% of Nissan.",
"There are plenty of markets with wide competition. Cell phones, for example. People talk about Android vs iPhone vs Windows vs Blackberry, but both Android and Windows (especially Android) have multiple manufacturers competing with each other. Motorola, LG, Samsung, Lumia, ZTE, and more. Computers work the same way, with \"PC\" encompassing dozens of manufacturers from Dell to HP to Alienware In fact, I can think of more industries that have a lot of competition than ones with only a little.",
"Only a few industries are limited to a small number of major players. Typically this happens because of *network effects* where you're better off having the same brand as other people -- for example computer operating systems, where you want lots of apps to work on your computer. Sometimes it happens from *economies of scale* -- it's easier for one company to run 20 supermarkets in the same city than for 20 companies to each run 1. Most industries that have a large number of consumers also have a large number of companies as suppliers.",
"I drove a truck for a very short time. But I noticed. Many many loads were finished bulky items. You haul a lot of pipe. Then there were dense loads, sheets of metal used to make pipe. Not as many loads. A car is a bulky item, lots of air inside. You have to be careful with it when shipping. You cannot pack it tight like you do sheet metal. All Japanese cars used to come from Japan, a long ocean trip. Now many of them are made in the USA. A car is many components made a lot of places. Once assembled it is more difficult to ship than the components. There is a lot of advantage to having multiple assembly points around the world. Other things can be built in one place and shipped easily. There used to be a method for deciding where to put a factory. The weight of all the components would be determined. On a flat map a pin would be placed at the source of each component. A comparable weight of washers would be tied together and strung from the pin. A string from that weight would be tied from the point of origin of the resource. All the strings would be tied together. The center of the strings would be where the factory should be located for the least cost of shipping. In other words a steel plant would be located between the source of coal, the source of the iron ore, and the destination of the steel. Exactly where depends on the weight or amount of each component. Now steel is made with electricity and steel plants are near waterways with barges.",
"Alot of car companies are under an umbrella. [article] ( URL_0 )",
"I would say that's relative, the automotive industry for a while was just a handful of players and while international trading has made it seem like there is a lot of choice, if you look back on the history of the industry, lots of other companies have folded or been absorbed into the companies you know today."
],
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[
"https://en.wikipedia.org/wiki/Automotive_industry#Top_vehicle_manufacturing_groups_by_volume"
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"http://www.monitor.co.ug/Business/Auto/Who-owns-what-in-the-auto-industry-/688614-2272688-jc9mq8z/index.html"
],
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} | [
"url"
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|
7ar2ay | Why does Carbonated water that has gone flat taste worse than Regular water | Chemistry | explainlikeimfive | {
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"text": [
"Because it is acidic. The CO2 reacts with the water creating carbonic acid, which is what gives carbonated drinks their bite. When it goes flat, you just have regular water with the acid but no bubbles.",
"**Okay here is the ELI5, detailed below answer below. Flat water tastes different than regular water because even though the CO2 leaves the water it still leaves a large enough mass of bicarbonate that the water tastes bad (compared to regular water). The key point here is that the dissolved carbonate species (bicarbonate and carbonate) don't leave solution, just CO2. *Detailed* The answers about increasing acidity are not correct. When the bottle is sealed it is supersaturated with CO2, which forms H2CO3 in water which then forms H+ and HCO3- which forms a miniscule about of H+ and CO32-. This is acidic. When the water goes \"flat\", the CO2 leaves causing a shift in the equilibrium to the left, ie causing HCO3- to react with an H+ to form H2CO3. This *reduces* acidicity and causes the water to be more basic. You are probably tasting bitterness of \"basic\" ions (bicarbonate), not sourness of acidic ions. *remember this is ELI5, I'm using terms like basic and acidic loosely. For knowledgeable, I mean increase hydroxide and decrease in hydronium. Yes, still acidic, but less so. (bicarbonate is not really a\" basic\" ion and I hate that term anyway. It has a pKa around 6.5 meaning it's a pretty good circumneutral buffer...it does taste bad though) **You can try this at home. Take some baking soda (sodium bicarbonate) and add it to water. It does not taste good. Like \"flat\" water. Or try baking powder if you have that.",
"This is actually why Guinness made their stout partially infused with nitrogen. They wanted to make the beer less bitter, but keep the same recipe. By replacing some of the CO2 with nitrogen, the carbonic acid is reduced, thus lowering the amount of bitterness. They were the first to do this. It also makes for a more silky mouthfeel with the smaller bubbles. Yummy",
"A lot of folks are answering correctly here, but I think the thing that is difficult for me to understand is why bubbles/carbonation should hide/mask the acidic taste so dramatically.",
"The bubbles are made by adding pressurized CO2 to the water in the factory. After the water has gone flat, a little bit of the CO2 stays dissolved in the water, and it tastes a little bit acidic. Is the same thing that is happening in the oceans with climate change, acidification because more CO2 is being dissolved in the waters (~~I'm assuming a higher temperature and pressure means CO2 becomes more soluble in water~~ EDIT: so neither temperature nor pressure are key factors in ocean acidification, just CO2 concentration, thanks for the clarification).",
"Dissolved CO2 in water will form carbonic acid, mostly HCO3- and a bit of H2CO3 in equilibrium. So, when there's a lot of carbonic acid or a catalyst (mentos and coke everyone?) the carbonic acid will form CO2 bubbles that scape the beverage. But when a significant amount of carbonic acid has been consumed by this reaction and we say that the water has gone flat, you still have some carbonic acid but not enough to form a bubble. The water is still acidic so it tastes weird. If you know something about thermodynamics and/or surface science, you'll know about how nucleation requires oversaturation, overheating or a catalyst. In any case you can look up the reactions so you can see how there's equilibrium.",
"Another reason that I haven’t seen mentioned here is that a lot of times carbonated water will also contain a lot of minerals, TDS of 500 and higher. Manufacturers actually often carbonate mineral water to hide the taste of mineral water - once the fizziness ‘runs out’ you get to taste all the micronutrients that you otherwise wouldn’t. You can try ‘Medicinal water’ with TDS 1500 and higher and you’ll feel the taste immediately. Source: I work in a drinking water industry.",
"The same reason that carbonated water that is still fizzy tastes worse than regular water - because the carbon dioxide in it makes carbonic acid. *Ducks the ire of angry Germans*",
"I'm not an expert in chemistry but I'll give this a shot. To carbonate water , carbon dioxide is added to the water. But carbon dioxide is slightly soluble in water(it can dissolve in water, but very slightly), that's why rainwater does not have a pH of 7. As acids taste sour, the carbon dioxide dissolved forms carbonic acid. This acid gives it the sour taste, which tastes worse than regular water. When the carbon dioxide escapes, carbonic acid is still left behind. Therefore, the sour taste still remains."
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7ara2h | Why do peoples singing ranges change if they don’t sing as often as they used to? | For example, I used to be in choir and was a Soprano 1 and could hit all of these insanely high notes that all Soprano 1’s typically can. But I’m not in choir anymore and I can still hit a lot of high notes that I did while in choir, but instead of being able to hit all of these really high notes, I can now hit these pretty much Alto 2 notes, that I’ve never been able to do. I’ve heard of this happening to other people but have been unsuccessful in finding a legitimate answer. | Other | explainlikeimfive | {
"a_id": [
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"text": [
"Singing is like training/exercise for your vocal chords. When you stop training them, they will change. When you were in choir you were singing for the highest section, so you were pretty much only singing high notes. You were in this way training and exercising your vocal chords to hit high notes so that's what they were focused on. Now that you're not in choir your vocal chords aren't trained the same way they used to be; because you aren't singing high notes on a regular basis, your vocal chords are no longer focused on hitting those notes and have become relaxed. Because your vocal chords aren't focused on high notes and are consequently more relaxed, you're able to hit low notes that your soprano-trained vocal chords couldn't have."
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