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6ko77i | Why is it not possible to grow taller after puberty? | Any tricks to force the body to grow in the early 20's? | Biology | explainlikeimfive | [
"djnoxqs",
"djni3ha"
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"Linear bone growth occurs at \"growth plates\" near the ends of the bone. These plates are made of cartilage. These plates form bone by extending their cartilage matrix, which later becomes mineralized into bone as we know it. The end result is a longer bone and a taller you. During childhood, hormones (e.g, GH) stimulate these plates to do their thing, but around early adulthood, these growth plates \"solidify/close\" and cannot lay down new cartilage for further growth (this is also hormone-mediated). So once these plates ossify your final adult height has been achieved."
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bwdk1l | Is it more efficient to walk in a staircase-like pattern, or “down and across”? | I live in a city and, like most cities, it’s pretty much a grid. My daily destination is the exact opposite location of where I live. I was interested in knowing which method of walking will save me the most time, or if it matters at all? | Other | explainlikeimfive | [
"epwtifs",
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"It doesn't matter. What you are talking about is called the [Manhattan Distance]( URL_1 ) -- also known as [Taxicab Geometry]( URL_0 ). If you can only walk on grid lines, then it does not matter if you follow a zigzag pattern or all-the-way-down-then-all-the-way-across. In practice, not all grid lines are the same. You should choose the path that is the easiest for walking -- crosswalks that are less crowded and street crossings that don't have long red lights."
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63ir05 | Why does weed make me hungry? | Biology | explainlikeimfive | [
"dfug1hl"
] | [
"No one really knows, but some evidence suggests that the THC affects areas of the brain which control taste and smell, making them more sensitive. The higher sensitivity then stimulates your appetite. Other studies suggest that it stimulates the hypothalamus which blocks signal receptors that you're full. These studies are done on mice, but the brain chemistry is similar enough that the conclusion is a similar effect occurs in humans"
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f3lvd6 | What caused houses to go from having crawl spaces underneath to being on a concrete slab, no space underneath? | Engineering | explainlikeimfive | [
"fhjqmju",
"fhjsr91"
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"Slab-on-grade is the cheapest, simply put. Most houses are built by larger real estate developers these days, rather than smaller home builders, and profits are the #1 concern."
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10
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7gwo2f | Why Is Companies giving Senators a big stack of money to get there way not considered bribery? | Other | explainlikeimfive | [
"dqm9s5a",
"dqm9scz"
] | [
"Companies do not give Senators big stacks of money to get their way. Just like I could set up a group that advocates for issues important to me, and either fund it with my own money or through donations, and then in turn decide to donate money to campaigns of candidates supportive of issues important to me - companies can do the same."
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6lzz1y | How will Elon Musk's battery fix South Australias energy problem if it can only power 30k homes? | How will it force prices down as the premier claims? | Technology | explainlikeimfive | [
"djxw15d"
] | [
"It won't 'fix' everything on it's own, it's when you combine it with all their other power stations it provides (in theory) enough extra power to make up for current shortfalls. It needs to be noted also that it won't only be connected to just 30k houses, it will be spread over the grid. It provides the equivalent power for 30k homes, but this will be shared by everyone in SA. And it will do it (in theory) for a lot cheaper than the current methods (esp coal). The initial saving won't be much (maybe a few dollars on your bill) but what it means if it works is that when it comes time to build new power stations/replace old ones they have a better cheaper option available. Long term, this will mean more similar projects will be built, causing (again, in theory) prices to go down, because people will naturally want the cheapest option - as long as it works."
] | [
3
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nvxa2y | why can't we just use some part of normal storage as RAM? | Technology | explainlikeimfive | [
"h15nw79"
] | [
"We do. It's called swap space. It's a last resort because even an SSD is hundreds of times slower than RAM. A hard drive is a million times slower than RAM making the problem even worse. But honestly it's not needed as much in these days of fairly cheap gigabytes of RAM."
] | [
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jbp7zh | How does orbit work? | I have a masters degree in engineering, but I still can't wrap my head around how moons stay in orbit or why planets orbit the sun or why the solar system is a plane. Help! | Physics | explainlikeimfive | [
"g8wl2yx"
] | [
"Imagine you throw a stone directly forward, it will fall to the ground. Throw it harder, it will travel further, but still fall to the ground. Now imagine you you have this huge throwing machine that can throw stuff really far. So far, in fact, that the earth starts to curve away by the time the stone starts to fall back to the earth. The stone keeps falling, the earth keeps dropping away from it. The stone is now in orbit! Obviously there are other complicated things to consider, but those are the basics."
] | [
14
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9vjjx4 | If someone is getting rich, someone else should be getting poor? | Economics | explainlikeimfive | [
"e9cog6h",
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] | [
"Since money is fake, it’s not bound by conventional laws of balance. There is always an exchange, but it’s very disproportionate, and ridiculously hard to trace every step that led to you getting that wealth. If it’s at a job, there’s the cost of the building you work, the cost of products or service you produce, the cost of your time, the cost of the people who produced or procured the ingredients that *you use* to make your product, etc."
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bre3co | Why does using a chip credit card at the pump take so much less time than using one in the store? | Technology | explainlikeimfive | [
"eocv6ep"
] | [
"Transactions at self serve pumps are often offline, so the card will say this person is good for certain amount of money. After you've filled up, the transaction is sent to your bank and taken from your account. Transactions in the store are often online, so a request is sent over the internet to your bank to check if you have available funds. Online transactions have to go through various networks and be processed by software so it takes longer. Source: I implemented a debit card system for a bank."
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11
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i2imwd | what exactly stimulates the bladder to push urine out when sitting on the toilette. | Biology | explainlikeimfive | [
"g058eox"
] | [
"It's pretty complicated. Apparently, you can inhibit the reflex, which would at some point happen on its own, if you were not conscious. What's happening while you're preparing is that you take back that inhibition, and the reflex takes more and more control. This feels like \"being urged\", because you can't control what happens anymore. [ URL_0 ]( URL_0 )"
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77s8bx | Why different alcoholic beverages illicit a different response | Culture | explainlikeimfive | [
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"In my experience, while I know anecdotes are not permitted, the only difference in alcohol for me is the strength and speed of drinking. Ethanol gets you drunk period and strong stuff does it faster. However, our sense of smell and taste are pretty heavily wired to our memories, and we tend to have preferred drinks when we feel a certain way. I honestly believe it's bias that people \"only get crazy when they have tequila\" when usually they only agreed to have tequila because they felt like getting crazy. ( Or they don't usually drink liquor and they end up drinking tequila and blaming the taste instead of the booze. )"
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l0pfex | Why can't we just create a new liquid fuel to replace gasoline? | I'm a casual car fan and with all the news about electric cars coming i've always wondered why we dont just make a new fuel to take gasoline's place, also considering that ICE cars are pretty cheap and electrics are aiming for high prices it seems finding a way to repurpose the normal car would be a smart idea. since every chemical we make seems to be combustible to some degree anyway why hasnt this been looked into? is it because of environment issues or cost or something else? | Chemistry | explainlikeimfive | [
"gjus0f3",
"gjus6mi",
"gjusp65"
] | [
"Well, that's basically ethanol. The thing is that it's more efficient to just collect energy directly from the sun or wind and put it in a battery than it is to cover the planet in corn fields in order to make ethanol."
] | [
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ddae7y | Why is the Sabbath considered to be Sunday in Christianity but Saturday in Judaism? | Culture | explainlikeimfive | [
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"It isn't. The Sabbath is on Saturday. It's just that Christians do not celebrate the Sabbath. Church is on Sunday because the Resurrection occured on a Sunday."
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ddni0p | How do pc gamers have an unfair advantage over console players when playing the same game using a mouse and keyboard over a controller ? | Technology | explainlikeimfive | [
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"It's substantially easier to input precise movements with a mouse than with an analogue stick. So much so that PC games usually will not have aim assist enabled by default if it's even available in the game. If you think about how much travel there is in an analogue stick compared to the area you have to move a mouse, you can probably imagine it would be much easier to make fine adjustments with a mouse. In FPS titles and such it could be seen as an unfair advantage as the mouse facilitates greater accuracy with equally skilled players compared to their console playing counterparts."
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8rpino | [Biology] since male seahorses can get pregnant, why are they male and not female? | Biology | explainlikeimfive | [
"e0t695z",
"e0t6spb",
"e0t68ni"
] | [
"They don't get pregnant. They still provide the sperm, while the females provide the eggs. It's just that later the males carry the eggs to maturity."
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d7stur | How do wolves and other carnivores survive by only ingesting protein? Don’t they need other nutrients to survive? | Biology | explainlikeimfive | [
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"Meat contains more than just protein. It is high in protein and not as rich in the same micronutrients that vegetables have, but it has more than enough to sustain carnivores, especially since their bodies have evolved to expect that particular blend of nutrients. The blood in meat is really high in iron, for instance (although that form of iron can be hard for some animals to absorb.) It’s also why it’s bad to feed cats dog food. Dogs can eat just meat or other stuff. They’re bodies expect them to kind of eat whatever but cats bodies evolved to expect cats to eat only animals and all of them, so cats actually need to eat parts of the animal that we might remove, such as the liver, or else they won’t get all their nutrients. Hope that helps!"
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7e3ch6 | In the US, when a product is specified as freshly cooked or freshly baked, what does that mean and what is the lowest standard to classify as "fresh"? | Other | explainlikeimfive | [
"dq2am14"
] | [
"In the case of juice in the US, for it to have the fresh label it cannot have been pasteurized per the FDA. So almost all juice you buy in the store is not fresh and seldom will you see it on the label. Regarding cooked foods I don't know if there is a legal requirement for that or not."
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kdzp8g | How do DNA tests determine ethnic origin? | For instance my great grandmother was an immigrant from Germany, however, on my grandmother's DNA test it came back mostly Iberian. This indicates her ancestors moved from Iberia to Germany at some point, but it got me thinking. How do we determine what is German genetically or for other ethnicities? | Biology | explainlikeimfive | [
"gfzkzcb"
] | [
"They take samples from people with deep roots in a region and use that as a starting point to match against. As userbases for different services expand, they can identify more regional commonalities like that. Just keep in mind that results like that are going to be fairly loose and inexact, and humans have moved around a lot throughout history so answering questions like how far back you’re measuring makes a big difference. My DNA results come back as mostly Northern and Western European, which is correct. But if you’re going back two generations instead of 10, then I’m entirely from North America. If you go back 100 generations, my ancestors are very likely from different areas entirely. I’m not going to say the tests are inaccurate, but keep in mind their limitations."
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c40c9d | What stops websites from taking your Credit Cards? | You know when you input it to checkout or they "save it" isn't it saved in a database? Whats stop them from using it. And I'm not sure how safe sites are with "secured checkout" I don't even know how that works and explaining that would be nice. | Technology | explainlikeimfive | [
"erue7vr",
"erukygy"
] | [
"Nothing stops them from using your card, but you can see how much money went where in your banking app. If you bought a shirt for 30$, and in the app you see that 30$ went to a shirt seller and another 50$ went for something you know you didn't buy, you can call your bank to block the card and see if you can get your money back. Also, saving sensitive data into database like passwords and card numbers is usually done by encrypting it. Web developers who made that website can probably see what's in a database, but they can't read it since it is encrypted so it's useless to them. Secure checkout can also mean that your card data is encrypted while traveling from your pc to the server, so no man-in-the-middle attacks can occur (no one can intercept and read card numbers before they reach the server). There's some more stuff going on which I'm not very familiar with nor good at explaining it, so I hope my answer covers some basics."
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angtuo | Why do touchscreens and trackpads work with 'organic' materials (fingers, bananas, etc) but don't work with the majority 'inorganic' materials (metals, plastic, etc.)? | Technology | explainlikeimfive | [
"eft7g0v"
] | [
"Touchscreens work by detecting capacitance of whatever is near enough the sensors. They're calibrated to respond only to the values that are expected from human skin. The other organic stuff just happens to have similar enough capacitance to human skin. Metals and common plastics being aren't that close."
] | [
13
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8angrj | Up until about ten years ago, people in photos taken with flash almost always came out with red eyes, but now you never see people with red eyes in pictures - what happened? | Technology | explainlikeimfive | [
"dx01org",
"dx01p41"
] | [
"Two things really happened. First, the way flashes happen is engineered to give the eyes time to close the pupils, reducing the reflection. This is both the color and quality of the light, and the flickering that occur before the photo is taken. Second, the software now involved in nearly every photo-taking device recognizes red-eye and can mask it out. You can still get red-eye, especially on older cameras, with unsophisticated flash, and if you use film."
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8vvmws | What is, and what are the consequences of Thrombolysis? | My uncle got hospitalized a few minutes ago with acute stroke, and my mom (working as a nurse for 29 years now) told me, there's a very high chance of him having thrombolysis. She's too shook to explain it to me, and so am I, but I just can't stop thinking about this "scary word" echoing in my head. | Biology | explainlikeimfive | [
"e1qnzxs",
"e1qq6eq"
] | [
"thrombolysis is the process of breaking down blood clots in the blood stream and is used to treat certain types of strokes and heart attacks.. the main danger with it is unstoppable bleeding since your body doesn't clot up cuts like normal. on a more personal level, i hope your uncle recovers."
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ley0eq | How does your brain communicate with your muscle to know exactly how far to throw a football to hit a target? | Biology | explainlikeimfive | [
"gmiufbh",
"gmir8by"
] | [
"I answered similar questions over a year ago. I'll copy paste and integrate the answers below: To make any movement, you need to flex different muscles that exert forces at different angles, and at different strengths and for different durations and kinetics. If you want to for example scratch your head, you need to flex your deltoid/shoulder muscle to raise your arm, this needs to start fast but slow down such that it doesn't overshoot and hit your head, therefore an opposing muscle like the latissimus dorsi needs to begin flexing towards the end of the motion, gradually to make your arm move smoothly. At the same time, somewhere during the motion, you need to flex your elbow with a number of muscles, while turning your forearm outwards (supination). By the time your hand reaches your head, you need to flex your fingers and extended in a specific pattern to scratch your head, you use a large amount of muscles to coordinate that. So one part of the computationally heavy process is coordinating which muscles to flex at which times to get a given motion. But there's another part, the strength of contraction of each muscle. Your brain divides each muscle into motor units. Each unit is composed of a neuron and a number of muscle fibers that it innervates. Motor units vary in number (different muscles have different amounts of motor units), size (therefore force), and type of fibers (fast and powerful, slow and weak but fatigue resistant, and medium). Your tendons and muscles and so on have proprioceptors which sense tension. As your brain matures from childhood, it undergoes learning processes much like a computer, it tests different neurons and senses what that corresponds to in terms of tension from your proprioceptors as well as seeing how far the arm went and how much force this corresponds to physically by eye. You also use other senses like mechanoreceptors sensing pressure in the skin like when you grip something. Over the years, your brain calibrates itself (I don't want to drive you crazy with info, but it also calibrates how faster frequency firing gives more force in a single motor unit). Meaning, it knows which muscles are needed to start a movement, which motor units it should start with for a quick start/acceleration, which units it should recruit to increase force to the requisite level for whatever object you want to lift or move, which other muscles are needed to synergistically stabilize the movement (like shoulder muscles, chest muscles, balancing muscles in torso and legs, etc), and which other muscles to recruit and how (in terms of motor units) to antagonize the movement towards the end so that you don't overshoot and hurt a join, and also when to stop flexing the initial muscles you started with. This information is stored in your cerebellum, this is where you store how you coordinate all this stuff. But when you want to do the actual action, things often don't go according to plan, muscles may not be as warmed up, as big as you learned or as weak, or the assessment of needed force may be off, etc, so your brain actually gets live feedback during the action from the proprioceptors, eyes, and mechanoreceptors to ensure you're following the proper trajectory of motion. Any tiny deviations are quickly computed and the neural output is modified to correct course. It's actually insanely complicated, the mathematics involved reach really high derivatives like jerk, snap, crackle and pop. You know, you have for example acceleration being the derivative of velocity (so it's change in speed, or change in rate of change of position). Jerk would be the rate of change of acceleration (rate of change in rate of change in rate of change in position), and so on. Your brain computes to really high levels of these derivatives to ensure that the muscles move in ultra smooth fashions. All this information of which muscles, how strong, for how long and how (mathematically) is stored in networks of neurons within your cerebellum which is this little brain you have at the bottom back of your skill. If you do an activity many times, you brain stores this information quite strongly (the connections between the neurons in the specific network become really strong making them easy to activate again). That is how muscle memory works, it's in the brain."
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ck30lt | What is the difference between "instantly" and "instantaneously"? | Other | explainlikeimfive | [
"evip219"
] | [
"'Instantly' is relative to a preceding action, similar to 'immediately'. If something happens instantly, it happens right after the preceding action. E.g. 'I clapped my hands, and the lights instantly dimmed.' The actual act of dimming from brightness A to brightness B may take several seconds, but the word 'instantly' indicates that they did so immediately after I clapped my hands. 'Instantaneously' is relative to the start of the action itself. If something happens instantaneously, it happens very quickly. E.g. 'I clapped my hands, and the lights instantaneously turned off.' There may be a slight delay before the lights turn off, but the word 'instantaneously' indicates that they did so in an instant, as opposed to, say, slowly getting dimmer until they turn off."
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e84ukq | YouTube's monetization system when it comes to controversial but popular YouTubers, i.e. PewDiePie. | Other | explainlikeimfive | [
"fa9ffz0"
] | [
"So Youtube has a system of revenue-sharing. Advertisers will pay Youtube money to advertise on YouTube videos, and the advertisers will pay more money if their adverts will be put around popular videos that get millions of views. Youtube then gives some of that money to the people who *posted* the video on Youtube. Sometimes. But sometimes they don't give you that money, and sometimes they block ads around that video because advertisers don't want to be associated with that particular content. This is \"demonetization.\" It's Youtube saying \"we'll give you some of the ad revenue we get from your videos, but not if that video breaks certain rules.\" So sometimes you have popular Youtubers, but they make a controversial video, and that video will be demonetized, meaning Youtube is not gonna share the ad revenue with the Youtuber for that video. They might even block ads on that video altogether. The goal of this is to remove the financial incentive to make controversial content. Some controversial content, despite being socially irresponsible, still might be widely popular and receive a lot of views and engagement. That content *might* generate a lot of ad revenue, which would encourage you to continue making content like that. Youtube doesn't want to be involved in that."
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o66rhd | Why do powdered milks spoil faster when mixing with water? | Chemistry | explainlikeimfive | [
"h2qnet4",
"h2qt28i"
] | [
"moisture is a breeding ground for bacteria, in general any food product that has moisture in it will expire faster then something dry. Its why people dehydrate things like beef jerky to make meat last longer"
] | [
10
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csb3xf | Why are bugs attracted to light? | Biology | explainlikeimfive | [
"exdrpmf"
] | [
"At nighttime, Moths and such are drawn to it because they are genetically programmed to navigate by the moon. Man made light has only been around for a couple hundred of the millions of years that keeping the only source of light over their shoulder has been working for them. They insist on trying (it's all they've known for millenia) to keep the moon over their shoulder, but it's not the moon.....It's your porch light, and they just spiral into it because it's not thousands of miles away."
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no1y94 | if you picked a scab over and over again each time it formed, how would a cut ever heal? Would you have this wound forever or would it heal eventually regardless if you kept ripping off the scab? | Biology | explainlikeimfive | [
"gzxrhgk",
"gzxvr2q",
"gzy48q1",
"gzy9w10",
"gzyzmad"
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"According to the experiments preformed by a younger me you need to sleep eventually and that’s when it heals over"
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110
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60pa6z | What scientifically stops us from creating life? | We know what we are made of but what stops life from starting when we put the necessary ingredients together? Edit: I'm not talking about creating another human. But just a small single celled form of life. | Biology | explainlikeimfive | [
"df8gk8z",
"df8c9h6",
"df86ezg",
"df8an3h",
"df88924",
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"By some definitions, we already have. We can create 100% artificial DNA, use it to replace the DNA in a single celled organism, and get a new, novel lifeform that uses that synthetic DNA. What we can't do is create everything from scratch, we still need a natural organism to kick start it. The question is when does that become creating life? If I use one lifeform to create something completely new and difference, does that count?"
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iujf9a | What exactly are Pyramid Schemes? | Economics | explainlikeimfive | [
"g5l0a03"
] | [
"They are almost always scams whereby the person or group starting it put in some money to make it look legitimate, then they advertise and recruit more people who pay in to whatever the program is. Part of the program is recruiting more people who pay in to the program. And then *those* people recruit even *more* people who pay in to the program. All that money from all the levels finds its way up to the top somehow. It's called a pyramid scheme because it starts with a small group of people who recruit a larger group who recruits an even larger group so that it spreads out like a triangle or pyramid. They're considered scams since you're not really buying anything, just paying money to be a part of something. And then recruiting more people to be a part of something. And you might get *some* of that money from recruiting those people but for the most part that money just goes up. \"Multi-Level Marketing\" (MLM) operations are oftentimes associated with Pyramid Schemes, but the difference is that with MLM you're not just trying to recruit people, you're also actually selling a *real* product (like cosmetics or knife sets or encyclopedias). The problem with these is that it's generally a lot harder to sell these products than the managers of the operation make it seem, so you might buy $200 worth of cosmetics for $500 with the promise that \"you can sell this at the retail price for $800!\", but you'll be lucky if you sell it all."
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
|
m8k8om | Can someone explain the theory that the mind exists outside of the body? | Other | explainlikeimfive | [
"grhpt8i",
"grhs3u4",
"grhqytz"
] | [
"Sure. It's pretty simple, actually. We don't fully understand the mind yet. Therefore, it must be spooky magic. QED."
] | [
6
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
kq1kt0 | How do CPUs deal with dead transistors? | A CPU has billions of transistors, of which any number of them could be broken or not working - how do they continue functioning without these transistors? | Technology | explainlikeimfive | [
"gi1irui",
"gi1f3pp",
"gi2689k"
] | [
"Welcome to the wonderful world of CPU binning. Have you ever wondered why Intel doesn't just make i7s? This is why. They try to make all i7s, say a 4 core CPU (not anymore but things have changed a little bit from this a 2 years ago because chiplets). Say a transistor in 1 core runs a little slow, its not broken but it can't run at full speed. Depending on this speed, they may take this down to a lower tier i7 or an i5. Say the transistor is completely broke. They will disable that core, disable the second worst core, and call it an i3 with 2 cores. I do want to note that the vast majority of the transistors aren't transistors in the cores, most of the CPU is cache. In which case they just disable the cache block with the faulty cache, and depending on how much cache they have to disable, they might also disable cores and call it an i3. In theory these cores disabled beside the faulty cores are perfectly good (though if disabling a working core, they will disable the worst working core), in fact back in the day you could re-enable them and use them, but just to keep a consistent and small set of cpu models they will keep a few of them. Do note that CPUs don't really have transistors dying with use usually. The only errors are usually in the manufacturing process. But overall they will only throw away CPUs that don't work completely. Everything else can still be sold."
] | [
44
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
63cbgv | How do ZIP files work? How can you compress a certain amount of information in a smaller amount of memory, and then be able to retrieve it all back in its original form? | Technology | explainlikeimfive | [
"dft09zw",
"dfszvmf"
] | [
"Imagine a tool box or a sewing kit, any of those neat little storage devices with cubbies and drawers and little fold-out shelves. How much space do they take up? When the are stored away, they take up very little space. You open them up, and take all the little bibs and bobs out to use, and they take up a more space. And once your really get into your project, and have things spread out all over your workbench, they take up a lot of space. There is really no one right answer to how much space it takes up, because it is really a tradeoff between space and accessibility. Information in a file, like a story, a song, a picture, or a movie, works the same way. It can be very accessible, and take up a lot of space, or take a lot of work to get at, and be packed away tightly. There is really no magic to making it smaller, you are just making the same tradeoff between size and accessibility. When you transform a file into the small but less accessible format, we call that data compression. It works by removing redundancy (sometimes called entropy) from a file, and encoding it in a more efficient form. Text files are normally encoded using something ASCII, where each letter is assigned an 8 digit binary code: A = 01000001 B = 01000010 C = 01000011 etc. With this scheme \"A\", a common letter, takes up the exact same amount of space as \"Z\", a less common letter. Even worse, the word \"the\", takes up three times as much space as Z, even though it is more common as well. Lossless data compression figures out which sequences are most common, and assigns them shorter codes, and leaves longer codes for uncommon ones. It might encode \"A\" as 1101, \"the\" as 01101, and \"Z\" as 1001100111. For every \"A\" it encounters, it saves 4 bits and for every \"the\", 19. The cost is that for every \"Z\", it uses 2 more bits, but overall this is a big win, because there are going to be more A's than Z's. One frequent question is why can't you just compress a file over and over until it is as small as you like? When you stow your tools and fold up your tool box, it becomes optimized for space, there just isn't any more space to remove. Similarly, lossless compression removes redundancy and optimizes how data is encoded so it takes up less space. Once you remove it once, there is nothing left to remove."
] | [
61
] | [
[],
[
"http://computer.howstuffworks.com/file-compression.htm"
]
] | [
"url"
] | [
"url"
] |
|
5zosko | Why aren't washer/dryers (one machine, two uses) more mainstream? | Engineering | explainlikeimfive | [
"deztnjl",
"deztxyz",
"dezyole",
"dezyrlx",
"df01srd"
] | [
"1. In most places, space (at least the kind necessary to have separate machines) is cheap so there isn't an economic driving force 2. 2 in 1 machines are more complicated which drives up cost and lowers effectiveness and potentially shortens lifespan 3. Less efficient from a throughput stand point: with separate machines, once the wash is done I can start a second load without waiting for the dry cycle as well 4. If my washer breaks I don't need to buy a new dryer as well and vice versa"
] | [
69
] | [
[],
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
a023in | How can a battle go on for weeks? | Whenever I'm reading about a battle, they often lasted for weeks or even months. How does that work? I assume it's not just one long, weeks-long round of movement, firing, flanking, etc., but what does a weeks-long battle actually look like? | Other | explainlikeimfive | [
"eadwn16",
"eadzpfa",
"eae0jw3"
] | [
"You have your guys dug in along the front, and the other guy has their guys dug in along a different front. Movements push the line around, but holding recently taken ground is hard. The lines might be different every day but it takes a long time to gain a decisive advantage or wipe out the other guy. You see a lot less of this in modern (post Korea) times, both sides use more mobility and try to avoid direct assaults where they don't have a significant numerical advantage."
] | [
36
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
hu4qwy | How do meteorologists and climate specialists determine the percentage for whether or not its going to rain? | Mathematics | explainlikeimfive | [
"fykw2d6"
] | [
"Simply put, it's the percent of the area that they expect rain to occur. Oftentimes, a band of showers will come through, but they aren't a homogeneous mass, there are pockets of lighter or heavier activity, and sometimes nothing at all. So, the meteorologist will run the data, see if they expect the band to grow, and come up with a percent chance of showers for the area. A 90% chance means that in ~90% of the area, it's going to rain < which essentially means simply, \"I might be wrong, but it's *going* to rain\""
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
|
bftseb | How come tadpoles can breathe underwater but frogs can’t? | Why and how does that work? Edit: I guess the real question is how does something develop lungs and go from breathing via gills to breathing air? | Biology | explainlikeimfive | [
"elg9sb4"
] | [
"Tadpoles have gills, so they breathe underwater like a fish. As they mature into frogs, they develop lungs."
] | [
6
] | [
[]
] | [
"url"
] | [
"url"
] |
cctymk | What makes blood a different "type"? | What's the difference between blood in people that means we have different "types" and why are some incompatible? | Biology | explainlikeimfive | [
"etpbhj6",
"etpc354",
"etpcbqb"
] | [
"Our blood contains antibodies and antigens. Different people have different antibodies/antigens. Antibodies attack antigens of the same type. Blood type O has no antigens and both A and B types of antibodies. Blood type A has antigen A and antibody B. Blood type B has antigen B and antibody A. Blood type AB has both antigens and neither antibodies. There is a final important antigen, known as D, which people are either positive for (they have it) or negative for (they don't have it). This means that someone whose blood type is A+ has antigens A and D, as well as antibody B."
] | [
32
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
ifm9cw | So there's this video of a crocodile gliding through water. | [This is a meme but, it shows what I mean ]( URL_0 ) Sorry for the bad quality example. I would like to know why the croc. does this. | Other | explainlikeimfive | [
"g2og7jn"
] | [
"The crocodile is just floating, relaxing and using as little energy as possible. Most reptiles arent super active unless they are hunting for food. If you are asking why he floats past, there must me a current in the tank that is moving him."
] | [
5
] | [
[]
] | [
"url"
] | [
"url"
] |
fukgxb | if your skin is constantly regenerating, and our body supposedly renews itself completely every 7 years, how come tattoos and scars last forever? | Biology | explainlikeimfive | [
"fmd9xlj",
"fmd9n1n",
"fmda500"
] | [
"The reason tattoo ink stays in skin forever has to do with the immune system. When you get a tattoo, the ink flows down the tattooing needle into the middle layer of your skin, called the dermis. That creates a wound, which your body tries to heal by sending macrophages (a type of white blood cell) to the area.With each penetration, the immune system is alerted there’s a wound going on and immune system cells are sent to the site. Some of these are macrophages which gobble up the ink in an attempt to clean the area. What’s left of the ink becomes absorbed by skin cells called fibroblasts. Most of the fibroblasts and macrophages alike become suspended in the dermis where they’re locked permanently. The dye in both cells shows through the body which is why you can see your tattoo in the first place."
] | [
7
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
8jqv2c | Why do more and more websites seem to be eschewing the standard "confirm password" format on account creation? | I've noticed on several websites that I have created new accounts on that they ask for Username, Password, Email, and whatever else they need. I am not being asked to confirm my password, however. In the past I assumed that the reason for this is so that I am sure I know what I set my password as, but what reason is there for removing this feature? | Technology | explainlikeimfive | [
"dz1rcqh"
] | [
"If you forget your password they can always reset the password by sending it to your email address. This is why you may only see one field for the password but two for the email as it is more critical that you get that right. Removing any unnecessary aspects of the account creation can make it easier and fast to make an account, increasing the number of accounts registered overall."
] | [
9
] | [
[]
] | [
"url"
] | [
"url"
] |
jxe1l6 | how does a day get attributed to something? | Other | explainlikeimfive | [
"gcw0nhv"
] | [
"you just advertise it heavily with commercials, ads, whatever. and work with retailers to offer sales/discounts on products like greeting cards, candy, flowers, or whatever. the more retailers you can get on board with it, the better you'll be able to do it. \"Sweetest Day\" is one of them, and depending on where you are, it might have caught on or not."
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
|
hyktrw | How does the medicine we consume able to target specific organs of the body that it wants to cure? | Biology | explainlikeimfive | [
"fzddku0",
"fzdd1b6"
] | [
"Unfortunately many times they don't. When they do they usually take advantage of some specific property that's is specific to that organs function. Radioactive iodine treatment for example takes advantage of the way that the thyroid gland tends to accumulate iodine. In another case you can get an implant or series of implants that stay in a specific area. The medicine will naturally be in a higher concentration next to where it is being released. Some cancer therapies use radioactive pellets for this. In other cases the medicine only affects specific protiens. Lots of painkillers for example will spread throughout the body, but they only affect certain protiens related to the nervous systems pain communication. In other areas the medicine is still there but doesn't affect anything. Similar to this in targeted chemotherapy the medicine is specifically crafted to target mutated protiens related to cell replication while leaving normal protiens alone. Again the chemical spreads out everywhere, but doesn't affect things it shouldn't affect."
] | [
6
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
|
7bijye | Why aren't there any successful third party candidates in major United States Elections? | Other | explainlikeimfive | [
"dpi9zs3",
"dpia0jp",
"dpia7ay"
] | [
"First Past the Post voting, which is the system we have, encourages strategic voting, which discourages diversity. Basically if a simple plurality wins, then everyone is encouraged to pool together and vote together, and it always devolves into a 2 party system, even in mathematical models. CGP Grey has some really good videos on this. Basically everyone chooses the lesser of two evils until it's just two parties fighting for the few swing people in between."
] | [
20
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
5ryej9 | What makes Bobby Fischer better than other chess prodigies? | Other | explainlikeimfive | [
"ddb5dx2",
"ddb4zxs",
"ddb9auj",
"ddb4qzm"
] | [
"A lot of it was he grew up in a place that had almost no support for top chess players. At the time America was a chess wasteland. The best analogy I heard was imagine an Eskimo created a tennis court in Alaska, trained by himself and then won Wimbledon."
] | [
21
] | [
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Bobby_Fischer#World_Championship_match"
]
] | [
"url"
] | [
"url"
] |
|
5o29l8 | What is dry drowning? | And how can someone dry drown in a pool? | Biology | explainlikeimfive | [
"dcg6d57"
] | [
"From what I can tell, dry drowning isn't \"drowning\" in the sense that water is filling the lungs and gas exchange cannot happen. In dry drowning, inhaling a bit of water can cause the vocal cords to spasm and block the flow of air from the mouth to the lungs. There is also a phenomena called secondary drowning, which can take place up to a day after swimming. If a child inhales some water, or even small amounts of water over time, that water can accumulate in the lungs and cause breathing problems later on."
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
au9dzk | For years NSA has raised concerns about the US power grid being hacked. What can the US do to protect the power grid? Going Green is critical for all, if nations are unable to protect their power grids, will that slow going green? | Technology | explainlikeimfive | [
"eh6iylh",
"eh6j1qm",
"eh6jm06"
] | [
"First, I think you're connecting two things that aren't connected. Going green, that is using more renewable energy sources, is not connected to the security of the electrical grid. Second, hardening the electrical grid against a cyberattack is an ongoing process. Most electric companies are private organizations but they work with various government agencies to coordinate a defense and restoration plan in case of a cyberattack. The exact details of what they're doing are understandably secret but they involve things like keeping control systems isolated from publicly accessible networks and providing manual overrides in case the automated systems are compromised. You can read more in this government report if you're interested. URL_0"
] | [
75
] | [
[
"https://www.ferc.gov/legal/staff-reports/2017/06-09-17-FERC-NERC-Report.pdf"
],
[],
[]
] | [
"url"
] | [
"url"
] |
|
bpyilc | what does alcohol do to your body to make you feel drunk? | Biology | explainlikeimfive | [
"enz0xxq"
] | [
"Alcohol does a lot of things to the body. The thing that makes you \"behave\" drunk is when alcohol gets into the brain. The brain works by brain cells signalling to each other. Alcohol interferes with how they are able to talk to each other, making them slower or not signal at all. Understanding why this happens is more about appreciating how complex some of the things we do are. Something like talking might seem very simple, but actually takes a lot of brain \"power\" to do, between choosing words, assimilating language, moving all the muscles involved in the voice box and the mouth. If you slow down or weaken some of the control involved with the use of a drug such as alcohol, then suddenly speech becomes much less controlled. Alcohol is not the only drug that has effects like this on the brain, but it's the most common drug because its normal to consume alcohol. We would consider similar drugs to be really quite dangerous to take in large quantities because of the measurable effects on the brain, liver and digestive system. Alcohol gets a free pass because it's considered so normal due to its long history of being consumed."
] | [
7
] | [
[]
] | [
"url"
] | [
"url"
] |
|
he4vzm | How are movies filmed in busy cities like New York City and San Francisco? | Technology | explainlikeimfive | [
"fvp3h9y",
"fvp7cjw"
] | [
"About 10 years ago I saw them filming Transformers in Chicago. Pretty much they shut down the street and all the cars and things that you see in the movie were brought in. It was pretty cool."
] | [
14
] | [
[],
[
"https://www.youtube.com/watch?v=3t4X3mBYWEw"
]
] | [
"url"
] | [
"url"
] |
|
ce0uca | Why does a cut hurt less after you put a bandage on it? | Biology | explainlikeimfive | [
"etxlj43",
"etxkknq"
] | [
"A lot of the pain comes from your nerves being exposed to the air, when you cover it and/or put pressure on it the air can't hurt you as much."
] | [
8
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
|
9mkv8g | Why do climate scientists predict a change of just 1.5 or 2° Celsius means disaster for the world? How can such a small temperature shift make such a big impact? | **Edit: Thank you to those responding.** I’m realizing my question is actually more specifically “Why does 2° matter so much when the temperature outside varies by far more than that every afternoon?” I understand that it has impacts with the ocean and butterfly effects. I’m just not quite understanding *how* it’s so devastating, when 2° seems like such a small shift I would barely even feel it. Just from the nature of seasonal change, I’d think the world is able to cope with such minor degree shifts. It’s not like a human body where a tiny change becomes an uncomfortable fever. The world (seems?) more resilient than a body to substantial temperature changes, even from morning to afternoon. And no, I’m not a climate change denier. I’m trying to understand the details. Deniers, please find somewhere else to hang your hat. I am not on your team. =========== **Proper Edit 2 and Ninja Edit 3** I need to go to sleep. I wasn’t expecting this to get so many upvotes, but I’ve read every comment. Thank you to everyone! I will read new comments in the morning. Main things I’ve learned, based on Redditors’ comments, for those just joining: * **Average global temp** is neither *local weather outside*, nor is it *weather on a particular day*. It is the *average weather for the year across the globe.* Unfortunately, this obscures the fact that the temp change is dramatically uneven across the world, making it seem like a relatively mild climate shift. Most things can handle 2° warmer local weather, since that happens every day, sometimes even from morning to afternoon. Many things can’t handle 2° warmer *average global weather.* They are not the same. For context, [here is an XKCD]( URL_1 ) explaining that the avg global temp during the ice age 22,000 years ago (when the earth was frozen over) was just ~4° less than it is today. The "little ice age" was just ~1-2° colder than today. Each degree in avg global temp is substantial. * While I'm sure it's useful for science purposes, it is unfortunate that we are using the metric of *average global temp*, since normal laypeople don't have experience with what that actually means. **This is what was confusing me.** * The equator takes in most of the heat and shifts it upwards to the poles. The dramatic change in temp at the poles is actually what will cause most of the problems. It only takes a few degrees for ice to melt and cause snowball effects (pun intended) to the whole ecosystem. * Extreme weather changes, coastal cities being flooded, plants, insects, ocean acidity, and sealife will be the first effects. Mammals can regulate heat better, and humans can adapt. However, the impacts to those other items will screw up the whole food chain, making species go extinct or struggle to adapt when they otherwise could’ve. Eventually that all comes back to humans, as we are at the top of the food chain, and will be struggling to maintain our current farming crop yields (since plants would be affected). * The change in global average (not 2° local) can also make some current very hot but highly populated areas uninhabitable. Not everywhere has the temperatures of San Francisco or London. On the flip side, it's possible some currently icy areas will become habitable, though there is no guarantee that it will be fertile land. * The issue is not the 2° warmer temp. It is that those 2° could be the tipping point at which it becomes a runaway train effect. Things like ice melting and releasing more methane, or plants struggling and absorbing less C02. The 2° difference can quickly become 20°. The 2° may be our event horizon. * Fewer plants means less oxygen for terrestrial life. [Precision Edit: I’m being told that [higher C02 is *better* for plants]( URL_0 ), and our oxygen comes from ocean life. I’m still unclear on the details here.] * A major part of the issue is the timing. It’s not just that it’s happening, it’s that it’s happens over tens of years instead of thousands. There’s no time for life to adapt to the new conditions. * We don’t actually know exactly what will happen because it’s impossible to predict, but we know that it will be a restructuring of life and the food chain. Life as we know it today is adapted to a particular climate and that is about to be upended. When the dust settles, Earth will go on. Humans might not. Earth has been warm before, but not when humans were set up to depend on farming the way we are today. | Physics | explainlikeimfive | [
"e7fhxo4",
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"It's not just about the temperature getting a few degrees warmer. An effect of rising CO2 levels is that the global average temperature will get a few degrees warmer. That average temperature increase is a benchmark only, not the problem in and of itself. It's the other effects of the same root cause of increasing CO2 levels that are a problem. The earth is a giant thermodynamic engine that takes in energy in higher amounts near the equator where solar gain is greater than heat radiated back into space, and funnels it to the poles, where solar gain is less than heat radiated to space. CO2 acts like a blanket over the system, keeping more heat in, but the equatorial zones don't heat much, they just shuttle that extra heat to the poles through ocean and wind currents. The same air currents also shuttle CO2 up to the poles, as can be seen in [this NASA model]( URL_0 ), which further reduces heat radiated back into space at the poles. This means that the poles are heating up a lot more than 2 degrees C. More like 10. The bulk of earth's frozen water is at the poles, so this rise of several degrees Celsius in the polar regions will melt a significant amount of land based ice, raising sea levels. This is going to cost trillions of dollars to either preemptively try to deal with or as flood damage. In addition, CO2 in the atmosphere is also absorbed into the oceans. As the CO2 levels in the ocean rise, the oceans acidify, due to the creation of carbonic acid, the same acid in your carbonated soda. You may have seen of heard of people dissolving baby teeth in a can of coke, and the same thing happens to carbonaceous minerals in acidified ocean water. So organisms with calcium carbonate shells like shellfish and coral grow slower and will likely soon reach the point where their structures are dissolving faster than they grow. This kicks the legs out of the base of the ocean's food web, and will largely collapse ocean life in near shore areas with the exception of algae and jellyfish. Finally, since the earth is currently being shifted out of equilibrium, the weather patterns are behaving like a top that is starting to topple, with extreme systems swinging across the globe. We are getting high pressure systems that park themselves over an area for weeks at a time, blasting the area with heat. In the ocean, this can kill corals, and much of the earth's coral reefs are already dying off as a result of these extended heat waves. Over land they reduce crop yields and can kill people. We have a circumpolar band of wind called the polar vortex that will start to meander, bringing snow to Florida and dropping temperatures across the Eastern US by 10-15 degrees C below normal in the middle of winter for weeks at a time, killing native plants and animals that aren't adapted to being able to survive that kind of cold for that long. These shifting weather patterns also change climate in areas, such that some areas will see extended drought such that there will no longer be enough water for the people that currently live there. In other areas, heavier rainfall increase flooding and landslide events, which cause millions to billions of dollars of damage to communities and kill people. Any time the world goes through a climactic shift, it becomes less habitable to the species that were adapted to the old patterns. Because of the interconnectedness of ecosystems, these effects ripple in a positive feedback loop that drives up extinction rates in a runaway process that can radically alter the biome. This is not good for humans in the short run or the long run."
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[
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jappkq | saliva is a "weak acid", how is it good for your teeth? | Biology | explainlikeimfive | [
"g8qxqwb",
"g8qxhwy",
"g8rf2zx",
"g8rgebu",
"g8rewv3"
] | [
"Strong enough to break down the gunk on your teeth but not strong enough to get through enamel. What gets through your enamel is in the bacteria that live off the gunk on your teeth. So if you can keep the bacteria down, with general cleaning and no acidic sugary drinks them saliva can do the rest."
] | [
185
] | [
[],
[],
[],
[],
[]
] | [
"url"
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"url"
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|
aixplx | How does Proton-Beam Therepy only damage a cancerous tumor and not the tissue around the tumor? | The UK has a new £125 million treatment center that provides proton therapy which will help destroy brain cancer as surgery in this area is dangerous. *Proton therapy, uses a beam of protons to irradiate diseased tissue. The chief advantage of proton therapy is that as a charged particle the dose is deposited over a narrow range of depth, and there is minimal entry, exit, or scattered radiation dose.* How can it only work at X depth? (The wiki was too confusing...) | Biology | explainlikeimfive | [
"eer82eb",
"eer8azt"
] | [
"Ionizing particles deliver maximum energy not at the surface, but at a deeper location under the skin. This phenomenon is known as Bragg’s Curve, and is usually explained by the particle slowing down as it travels through the material, thus it spends more time interacting with matter deeper down. By tuning the particle speed, you can adjust maximum energy delivery to whatever depth you want, and kill cells at that depth. Edit: some energy is delivered to the surface, that’s what causes the particles to slow down. So the technique is not perfect, and will cause minor damage at the surface. But the majority of energy will be delivered to the tumour site."
] | [
5
] | [
[],
[
"https://en.m.wikipedia.org/wiki/File:Comparison_of_dose_profiles_for_proton_v._x-ray_radiotherapy.png"
]
] | [
"url"
] | [
"url"
] |
6cpoxe | Why do some planes leave a trail of clouds and others do not? | Chemistry | explainlikeimfive | [
"dhwf85j"
] | [
"When you burn fuel you get water vapor, carbon dioxide, and some soot. If the air is cold and moist enough then the water vapor will condense out of the air, and the soot gives it something to condense on. Some planes are flying through air that's cold and moist enough, while some aren't. (This is a simplification; rapid changes in pressure can cause condensation trails as well, but the typical con trail is from moisture in the exhaust condensing on soot)."
] | [
7
] | [
[]
] | [
"url"
] | [
"url"
] |
|
hvxvls | I hear a lot about stem cells. What are they exactly and how can they help people? | Biology | explainlikeimfive | [
"fyw3qk8",
"fyw3run"
] | [
"Stem cells are basically 'neutral' cells that haven't decided what kind of cell they are going to become. While most of our cells have the same base DNA, they are highly specialized for their specific functions - white blood cells don't look or function like liver cells or kidney cells. A stem cell isn't any kind of cell yet - it is a 'blank' that can become any other type of cell (with some coaxing). While we are still probably years away from actual stem cell treatments, the idea is that we can use them to repair any type of cell damage that we can find. Have a spinal cord injury? Inject some stem cells and they will become new nerve cells to fix the issue. Need a new kidney? Put some stem cells in the organ printer and 3d print a functioning organ."
] | [
8
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
|
c7qc86 | how does someone run faster than someone else? | Biology | explainlikeimfive | [
"esgycg6"
] | [
"Running speed depends of 2 things: the length of your steps and the time between 2 steps. To run fast you need to take long steps and chain them quickly. To achieve this the muscles in your legs must be powerful (strong over a short time) as sprinters or tennismans muscles, but not necessarily very strong as weightlifters muscles."
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
|
9sx7j8 | What exactly is an "influencer", and what do they do? | Inspired by this disturbing little [New York Times article]( URL_0 ) about a loft specifically designed for the audiences of Instagram influencers :) | Culture | explainlikeimfive | [
"e8s36k1",
"e8s42t3",
"e8s3p3r",
"e8seoyt",
"e8s7ed7",
"e8se58c"
] | [
"Someone who has a social media account with a large number of followers, and uses it to influence these followers more or less subtly to buy things, and who is paid money from companies that make those things. Most commonly they are young women who on Instagram show off a cool, fashionable (and eventually completely fake) lifestyle involving lots of expensive brand clothes, accessories, and cosmetics."
] | [
52
] | [
[],
[],
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
lem3rv | What happens if you never cut the umbilical cord when a human baby is born? | Biology | explainlikeimfive | [
"gmfdenw",
"gmfdery",
"gmfhdp3"
] | [
"The child has to wear mid-riff shirts their entire lives. I think the cord eventually detaches from the infant on its own but there is a bigger risk of getting snagged and other complications if it’s not snipped"
] | [
11
] | [
[],
[],
[
"https://www.reddit.com/r/NoStupidQuestions/comments/1lq9nx/what_happens_if_you_dont_cut_the_umbilical_cord/"
]
] | [
"url"
] | [
"url"
] |
|
97axw5 | The sudden and extreme change in size of planets starting from Jupiter. | Why is it that from mercury to mars, planets are somewhat close in size, but then an abrupt and extreme increase in planet size occurs in Jupiter and then continues until Neptune? | Physics | explainlikeimfive | [
"e46skl4"
] | [
"We don't really know. It's believed that gas giants form far from the star where the solar wind can't blow the gas away, and rocky planets form closer in. The absence of \"super earth\" planets in our solar system and their formation process is not well understood. We have observed planets in that 3-8 earth mass range in other solar systems, but it's not clear what they're made of or how they form. Planetary formation and evolution is a quickly advancing field of study right now as data pours in from planet hunting missions."
] | [
4
] | [
[]
] | [
"url"
] | [
"url"
] |
jdbj0a | Everyone is a virgin and std-free until a certain point. So where do std's originate from? | Biology | explainlikeimfive | [
"g96v60v"
] | [
"Many STDs can be traced back to animals. Maybe even all of them, but I'm not 100% sure. They eventually get transmitted from animals to humans. HIV, for example, is thought to originate with Chimps. HIV crossed from chimps to humans in the 1920s in what is now the Democratic Republic of Congo. This was probably as a result of chimps carrying the Simian Immunodeficiency Virus (SIV), a virus closely related to HIV, being hunted and eaten by people living in the area."
] | [
17
] | [
[]
] | [
"url"
] | [
"url"
] |
|
6ae4cg | Why is there such a negative stigma against nuclear reactors? | Ive done extensive research into them and all the evidence proves they are the safest and most efficient form of energy. Why does the public fear (literally and culturally) these reactors so much? | Culture | explainlikeimfive | [
"dhds486",
"dhds2ds",
"dhdyly7",
"dhe0f4w",
"dhdsber",
"dhdt7z3",
"dhds3io"
] | [
"People tend to fear a small risk of a big catastrophe more than they fear a moderate risk of a small catastrophe. It's the same reason that people fear plane crashes but not car crashes. It's just a quirk of human nature."
] | [
52
] | [
[],
[],
[],
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
751fic | How does the smoke detector know the difference betweem smoke and steam? | Engineering | explainlikeimfive | [
"do39yjs",
"do2oj1i",
"do2rd9b",
"do2sjpf"
] | [
"There is many different types of smoke detectors out there. Some can't see the difference between smoke and steam, but the more complex ones does a good job of separating the two. The ones I use at work now is: * optical. (Think LED in one end of chamber and a photo-resistor in the other end. Mesures the amount of light that get through.) * double optical and thermal. (Uses two different angels on the chamber for the optical part to guesstimate the difference in smoke and steam based on different reflections.) * optical / thermal / gas. (Reads Co2. Works like a champ in theaters, clubs etc. that uses theatrical smoke on stage.) * only thermal. (Works on the principle of fire is hot. Heat rises and sets of the detector at a set temperature or if the temperature is rising very fast.) Double optical is very good at separating steam and smoke. (Use it in kitchens and locker rooms close too the showers. No problem with false alarms.)"
] | [
24
] | [
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
c6b99i | Why are there “acquired tastes”? Why do some things, like beer, whiskey, and food delicacies take a few tries to become palatable? | Biology | explainlikeimfive | [
"es7nuwu",
"es7ig0f",
"es8e02j",
"es96h8o",
"es8k5vv"
] | [
"or even black coffee. because it takes time for your tongue to become sensitive enough to separate out the slight and subtle distinct flavors. when you try something for the first time, you just become overwhelmed and that doesn't give you a pleasant taste. but the more you try it, the more you're able to taste the subtle flavors and less of that overwhelming taste."
] | [
5
] | [
[],
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
70ncrv | What's the difference between caustic and corrosive? | Chemistry | explainlikeimfive | [
"dn4g9a3"
] | [
"A caustic will damage organic tissue, but not necessarily damage inorganic materials such as metal or glass. A corrosive can damage inorganic and organic materials."
] | [
23
] | [
[]
] | [
"url"
] | [
"url"
] |
|
jpgr8q | If you could zoom in and watch something charge it’s battery, what would you see? | Like a cell phone or a laptop. Would it be like, a stream of electrons dumping out of the charge cord and into some kind of receptacle? Would they fill in randomly or orderly? What keeps them from escaping, thus keeping the charge? | Physics | explainlikeimfive | [
"gbfl05i",
"gbempe5",
"gbem4eq",
"gbeuzpl"
] | [
"Imagine a retail clothing store that has a bunch of customers but no sales. Throughout the day the customers ruffle through the neatly folded clothes, try them on and put them down somewhere else. Completely disorganizing the entire store. That is you using your battery. At the end of the day, the employees run through using their tiny hands to pick up crumpled clothes, fold them, and reorganize the entire store. That is the charging. The electrons come in through the wall, reorganize your lithium ions and leave."
] | [
166
] | [
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
9j021g | Bible "Book of Revelation" | Culture | explainlikeimfive | [
"e6nqvx1"
] | [
"The Book of Revelation is the last book of the New Testament in Christianity. The Christian Bible consists of the Old Testament and New Testament. What Christians call the Old Testament is the entirety of holy scripture for Jews, who simply know the Old Testament as \"the Bible\" or \"the Hebrew Bible.\" The Book of Revelation contains many prophecies for the future, most importantly, it prophesies the return of Jesus Christ to the Earth and the end of the world. It also contains many fascinating numerological and mythological artifacts, including seven-headed dragons, lions with three faces, and the famous Four Horsemen of the Apocalypse. The Book of Revelation was most likely written during the time of the reign of the Roman Emperor Domitian, who ruled between 81 and 96 CE."
] | [
8
] | [
[]
] | [
"url"
] | [
"url"
] |
|
5xcyrm | The Fed announced they will likely be raising interest rates soon. What does this mean for people who are in the process of picking out a house to buy? | Link to Article: URL_0 | Economics | explainlikeimfive | [
"deh372j"
] | [
"Interest rates are likely to be higher than lower. The change is probably small, 0.25%, but you should expect that banks will pass the cost on to you. Much of the increase is already baked into estimates, so don't expect a square wave in rates the next day."
] | [
4
] | [
[]
] | [
"url"
] | [
"url"
] |
fqs21b | why does the corn acquires the shape of a popcorn when exposed to heat? | Just a shower thought (question?) I can't get my mind out of. | Biology | explainlikeimfive | [
"flruw2k",
"fls47t0"
] | [
"Dried corn kernels are basically solid balls of starch. When you expose them to heat, the starch melts, turning into a liquid. Pressure builds up until the shell pops (\"pop\"corn), and the liquid starch is flung everywhere. But it cools off and solidifies quickly, so it doesn't go far. Popcorn is basically a frozen starch explosion."
] | [
21
] | [
[],
[
"https://www.youtube.com/watch?v=p\\_7Qi3mprKQ",
"https://www.youtube.com/watch?v=p_7Qi3mprKQ"
]
] | [
"url"
] | [
"url"
] |
693329 | Nuclear Fusion Reactors | Reading about the nuclear fusion reactor in the UK . What I can't understand is how these reactors can contain temperatures as high as these folks are saying, 100 million degrees Celsius? Wouldn't that melt any material known to man? Edit 1: thank you for all the great answers! Okay, so I can understand that it's not actually touching anything, but then wouldn't the heat generated by the plasma still be cause for concern? I understand that this heat is where we are getting the energy, but then if we're constantly pulling it, wouldn't that drastically reduce the temperature of the plasma? | Engineering | explainlikeimfive | [
"dh3fyw6",
"dh3cqfw"
] | [
"The part of the reactor that is 100 million degrees Celsius is plasma (the state of matter past air) and it is contained in a magnetic field. The magnetic field keeps the plasma from touching anything, which means it can only heat things up through radiating heat, which is a slow way to transfer heat (though at 100 million degrees it would transfer heat very fast even through radiation). Why this won't melt the reactor is how the reactor generates energy. Basically you flow a lot of water around the reactor to cool it off. The water boils into steam which turns a turbine. The turbine generates electricity. Now in the actual reactor they aren't using water, but a mineral salt that melts."
] | [
4
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
5swc0y | How the notion of "a god/gods" came around | I've been wondering about this for a while, as I don't understand how we'd come up with an idea like that without being crazy (Abraham for an example heard to kill his son from some mytholigical creature). I'm just frankly interested in how did they come up with these. | Culture | explainlikeimfive | [
"ddicng7"
] | [
"I'm not really able to give an in depth answer as I'm quite tired and it's nearly midnight, but I'll try in case nobody else sees this and answers you. I think its safe to say that most cultures started off broadly animistic, so without any real sense of how anything in nature worked everything was 'magical'. Questions as broad as why the sun moves across the sky to why pebbles in streams are rounded were way out of the realms of our knowledge. People began to explain the forces of nature around them in allegorical stories in oral traditions; folk tales were the only way information (and entertainment) could be handed down through generations. I personally think an emphasis should be placed by anthropologists on how young people died back in our early history too, 15 was basically 'middle age' - and it was in no way long enough for their brains to come to logical conclusions about the world around them before having their own kids (and subsequently brainwashing them with their own oral traditions/folktales/religious teachings.) The world was a scarier place to our ancestors, and death lurked everywhere. They didn't understand disease or anything like that, so they started to sacrifice to or worship/talk to forces of nature because thats all they could do. Sometimes it would work, sometimes it would not - but of course it was always coincidence either way. As time goes on, oral traditions get more grand. Each generation adds their own part onto the stories about creation and the forces of nature until they've basically become anthropomorphism characters in stories. Hence, they are no longer just a 'river spirit' for instance, but a God. Theres some theories surrounding many cultures, about when basically the concept of a God changed from being nature based to man based. As an example, in Norse and Germanic culture, there were two sets of Gods. One was the Vanir which largely represented fertility and the forces of nature. The other was the Aesir who despite also personifying forces of nature, were also often cited as being the first tribe through which all of the Germanic tribes originated. Odin, the chief god of the Aesir (or Woden, Wotan depending on culture) was always linked to the tribal chief or King at the time. In other words, it is likely that they saw their own ancestors (and king's) actions as being divine in addition to the world around them. They were no longer just pawns being played by the forces of nature but a force themselves. Monotheism came along in the middle east - no doubt most notoriously in Judaism, but the truth is that it was tried a few times before that as a system of control. Within polytheism, you have multiple Gods and temples to which you can turn to meaning the political power of the religion is essentially split. (You're unlikely to go to the temple of Mars in Rome for instance, if you work as a midwife - so therefore the religion kept everyone's opinions on things roughly divided.) In Ancient Egypt, a rule known as Khem began outlawing other temples except that of the 'one' God, Atun (a sun God which has many parallels to Jesus it has to be said.) The move was purely political as it removed the power of the priesthood. As the Pharaoh therefore had all the religious power religion, as well as politics, could be brought to bare on the population. I think (not entirely sure) that the next ruler after him restored polytheism however. The Abrahamic faith which came out of Palestine has many parallels and borrows literally hundreds of aspects of older religions from surrounding provinces - but ultimately monotheism (especially the 'conversion' tactics) is purely a political and domination tool which has been used to scare the commoners into submission with stories of bogeymen. Admittedly, perhaps it has had some role in civilising the planet, but only after the deaths of untold millions who would refuse conversion."
] | [
4
] | [
[]
] | [
"url"
] | [
"url"
] |
bf5r7o | Why are most women crazy about shoes? Is there a reason? | Culture | explainlikeimfive | [
"elb26iw"
] | [
"Because no matter how much our body shape changes we generally stay the same shoe size. Therefore shopping for them is never depressing."
] | [
8
] | [
[]
] | [
"url"
] | [
"url"
] |
|
gjfaeu | What's the difference between rechargable and non rechargable batteries? | Like, what's the chemical process that allows one to be recharged and prevents the other? Both retain a charge in the same manner, no? | Chemistry | explainlikeimfive | [
"fqkmtut"
] | [
"Rechargeable batteries use materials that can move the electrons backwards when powered the other way. Non rechargeable batteries absorb the electrons in a way that is very difficult to reverse. They are still popular because of lower cost and higher energy density."
] | [
7
] | [
[]
] | [
"url"
] | [
"url"
] |
5lyopu | Why does one person singing out of tune sound like ass, but 50,000 people singing out of tune sounds amazing? | Aside from the emotional impact of being together in a large group - do the different out-of-tune notes somehow cancel each other out, or combine to make new harmonics? | Other | explainlikeimfive | [
"dbzfrco",
"dbzujsm",
"dbzvl4v"
] | [
"Because they all are randomly out of tune, but just slightly, so they add up around the proper notes. On average you get a sound that is more intense around the right notes and their harmonics (which makes it sound non-dissonant), and the out of tune sounds just becomes a bunch of overtones making the sound a richer and more complex timbre. [See this old comment I made]( URL_0 ) for some technical details and visuals."
] | [
164
] | [
[
"https://www.reddit.com/r/askscience/comments/4mur7n/why_do_some_objects_emit_a_pitchless_sound_when/d3yqdk5/"
],
[],
[]
] | [
"url"
] | [
"url"
] |
mwjobq | What does the stomach’s microbiome do? What role do probiotics play for the microbiome? | Biology | explainlikeimfive | [
"gvikuc1"
] | [
"Your body does a lot of things with honestly not that much genetic material, however, it's not able to do *everything* that we need. Some chemical processes are only really done by bacteria, and we coopt these bacteria, give them food, and they give us the processes. A large number of these processes occur in the intestines during food processing. Probiotics *are* those bacteria, and eating probiotic foods reintroduces them to your microbiome after they may have been killed, like in a round of antibiotics."
] | [
4
] | [
[]
] | [
"url"
] | [
"url"
] |
|
evipet | what is pataphysics about? | Other | explainlikeimfive | [
"ffwbpws"
] | [
"Hard to explain, but if you think of a metaphor as being one step removed from a literal statement, a pataphor is two steps removed from the same statement. To use one example, take the phrase \"does the Pope shit in the woods?\" It only makes sense if you're familiar with the statements \"does a bear shit in the woods\" and \"is the Pope a Catholic?\". All three statements convey the same meaning, but unless you've heard the latter two, you'd be hard pressed to know what the fuck I was on about."
] | [
12
] | [
[]
] | [
"url"
] | [
"url"
] |
|
hh9t7q | Why does some furniture use Phillips head screws, while other use hex or torx? What are the advantages between the many different types? | Engineering | explainlikeimfive | [
"fw8tdf6",
"fw8tbi0",
"fw8xgob"
] | [
"a slot screw can't be tightened with a lot of force, usually you'll slip or snap the bit. But you'll see it in common things where a lot of hold isn't needed due to being easy to find things to use as a flat head. Philips Heads are common when needing to screw in multiple screws, but they aren't ideal for things of high hold where you need to make sure they go in tight and have to be removed and reused multple times I.e beds, as the heads can easily strip making them hard to remove or impossible to reuse again. Furniture will more oftenly use hex because one, Allen keys usually give access to tighten things even in small places and at angels including the lack of need to make sure you apply pressure to the bit when tightening or loosening the screw unlike flat or Philips heads where you need to apply pressure while screwing in a screw, while the hex is also deeper and a lot harder to thred usually finding the Allen key will thred before the actually screw head."
] | [
41
] | [
[],
[],
[
"https://en.m.wikipedia.org/wiki/List_of_screw_drives"
]
] | [
"url"
] | [
"url"
] |
|
ar6vty | how is concrete + steel so strong? What makes them a strong combo? | Engineering | explainlikeimfive | [
"egl6s3x",
"eglbnoh"
] | [
"Concrete has very high “compressive” strength, which basically means it can handle a heavy load pressing on it. However, it can easily snap like pieces of a Hershey’s bar. The steel inside the concrete increases the “sheer” strength of the pour, which basically prevents the snapping. Each part absorbs those dynamics of the load making the part’s job a little easier and the whole structure stronger as a whole. This synergy makes them a strong combo, but it is also that the thermal coefficient of both steel and concrete are nearly the same. This means that they will expand and contract at the same rate. If one expands or contracts faster than the other, their forces acting on each other can cause cracks, breaks, and voids."
] | [
20
] | [
[],
[
"https://www.youtube.com/watch?v=cZINeaDjisY"
]
] | [
"url"
] | [
"url"
] |
|
7cinnr | Beveridge Model vs Single Payer system | On the Wikipedia page for [Single Payer Healthcare]( URL_0 ), the [single payer section]( URL_0 #Regions_with_single-payer_systems) and the ["Beveridge Model" section]( URL_0 #Regions_with_.27Beveridge_Model.27_systems) both have different countries listed, but aren't they synonymous? What's the different between a Beveridge Model and a Single Payer Model? | Economics | explainlikeimfive | [
"dpq6uk5"
] | [
"The answer to your question is written in black and white in the links you provided. From the Beveridge Model section: > The term 'Scandinavian model' of health care systems has a few common features: largely public providers, limited private health coverage, and regionally-run, devolved systems with limited involvement from the central government.. Due to this third characteristic, they can also be argued to be single-payer only on a regional level, or to be multi-payer systems, as opposed to the nationally run health coverage found in Canada, Taiwan and South Korea."
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
5waemd | Why does every car that I've ever heard have a different sound in reverse? | Engineering | explainlikeimfive | [
"de8ive1",
"de8iqcb"
] | [
"It's the reverse gear. Most of the gears in your car are cut with helical teeth because they're much soother and more efficient. No one cares about reverse, though, so they cut that gear with straight teeth, which in turn means it's not very efficient. A part of that efficiency loss is the whining or whirring sound you hear when the car reverses. You can see the difference [here]( URL_0 ). All of the gears have teeth cut at angles, except one on the left side, next to the biggest gear on the left (which is 1st gear), which likely means that particular gear is reverse."
] | [
34
] | [
[
"http://previews.123rf.com/images/sydeen/sydeen1110/sydeen111000007/10966490-car-gearbox-on-isolated-white-background-Stock-Photo-car-parts-transmission.jpg"
],
[]
] | [
"url"
] | [
"url"
] |
|
gqjmfw | If humans can't see ultraviolet wavelengths of light, what is a blacklight? | Technology | explainlikeimfive | [
"frt473z",
"frt7x7z",
"frt2oyt",
"frt2nel",
"frt4olv",
"frtj034"
] | [
"Florescent pigments absorb uv light that's invisible and then re-radiate some back at a lower frequency. That's why only some things glow in a blacklight. It's also how dayglo pignents work."
] | [
1122
] | [
[],
[],
[],
[],
[],
[]
] | [
"url"
] | [
"url"
] |
|
8j8dk2 | Why do white people tend to get pink or red sunburns when they stay out in the sun too long, but darker skinned people usually just get darker? | So my skin would be considered brown and whenever I go out into the sun for too long, my skin tends to darken. However, whenever white people stay in the sun, their skin usually turns bright pink or red? Why is this? | Biology | explainlikeimfive | [
"dyxpurw",
"dyxroeg"
] | [
"People with white skin have less Melanin, the component of your skin that protects it from the sun. When white people hang out outside the sun fries their skin whereas people with dark skin simply have more natural protection. White people still have some melanin and can tan a little, and darker people can still be burned through their natural protection. How long you can stay in the sun without inviting its wrath depends on the amount of melanin your body produces."
] | [
9
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
ah3z5o | How do the kidneys know the difference between toxic metals and essential metals when filtering the blood and excreting the toxic ones into urine? | Biology | explainlikeimfive | [
"eeb9lr1",
"eebgcju",
"eebe62y",
"eec3hty"
] | [
"They don't know anything. The kidneys are filters. Every substance has different density, shapes and other properties, all of which can be used to filter things out or put them back in. It's like sifting flour. Anything too big or the wrong shape can't fit and thus gets sifted out. And sometimes they put things back in, such as minerls like iron which are need in small amounts but harmful in less amounts. Those get put back in in the right amounts. It's all biological eqivilants of sifters, sorting machines, and measuring cups, only on a much smaller scale."
] | [
21
] | [
[],
[],
[],
[
"https://www.karger.com/Article/FullText/83981",
"https://en.wikipedia.org/wiki/Renal_corpuscle",
"https://en.wikipedia.org/wiki/Table_of_permselectivity_for_different_substances",
"https://journals.sagepub.com/doi/pdf/10.1177/019262339802600111",
"https://watermark.silverchair.com/edrv0045.pdf?token=AQECAHi208BE49Ooan9kkhW_Ercy7Dm3ZL_9Cf3qfKAc485ysgAAAj8wggI7BgkqhkiG9w0BBwagggIsMIICKAIBADCCAiEGCSqGSIb3DQEHATAeBglghkgBZQMEAS4wEQQMOezxQTASEhdNByYdAgEQgIIB8u8kWUo_RW68vVYSmEVzoVfcKpbR8DX-qxgThgqHFQuX_FXMrgKiZbMLDSFwxQ7GXab4dGiIZxHBlSyTDHOeTzTCtUUHopXMw_ujEMwy6grdTqpp4kHQU-iX798O87Ms2t3t0Qe2fXucytG3sQBED0DMns5lVLSBJkDjOxzzNzkPP5myuzkeAF9DWDjIUSY3PE1a3Gekfs_PNAj2CEYY1TCUCvthCskZfX6DJcbyhbOInaTsmj7o3AVE8Mt7EyojoVpFQGbaXcqVwIVbvGdVS5es2WOF73QpX0TCWx",
"https://en.wikipedia.org/wiki/Van_der_Waals_force",
"https://commons.wikimedia.org/wiki/File:Gray1128.png",
"https://imgur.com/1D6y2Cc"
]
] | [
"url"
] | [
"url"
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|
6gckhq | Clean energy and electric cars are great and all, but crude is refined into many many other things. How are those other industries preparing for the day that there isn't enough oil in the world to meet demand? | Edit: Could be flaired as either economics, engineering, or chemistry... I couldn't decide. | Other | explainlikeimfive | [
"dip7rqa",
"dip7ne1"
] | [
"Clean energy and electric cars mean more oil is available for other purposes like making plastic. Even if we eventually run out of oil there's even more coal which could be used with some more effort. Or we could recycle existing plastics."
] | [
3
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
5pb7n9 | Why hasn't USA adopted Nordic countries education and health care system? | Culture | explainlikeimfive | [
"dcpteq2",
"dcptdzb"
] | [
"*Sigh*. Some of us have, it just doesn't go anywhere for a variety of reasons. The \"core\" reason is that when the European democracies rebuilt after WWII, they developed universal healthcare systems to ensure everyone had care. This was largely an expansion of the systems Germany used to strikebreak or otherwise help industrial workers even before WWI, and it spread relatively easily in the wake of WWII - it was also seen as a comfortable political compromise with socialism, which had arrived rather dramatically on the political scene with the influence of an emboldened and expanded USSR. Giving people free healthcare and high taxes but keeping most of a capitalist economy while rebuilding from a grueling war was where people would up. In the US, things were a little different. We have a very long history of wealthy people and their corporations having a lot of say in how things are run through several mechanisms. During WWII, it was really hard to get anyone to work for a company - most young men were at war, and there were only so many women who could or wanted to work in the factories or other businesses. This caused some problems, and part of that solution was the government stating outright that nobody could be paid more than a certain amount - but healthcare insurance policies were not considered \"pay\" by this rule. So companies started competing about health insurance instead of just wages. This eventually led to a system where the government, insurance companies, and the medical industry all have roughly-equal say in how things are run - and the medical industry and insurers both have a lot of say in how the government is run, since they're fairly wealthy and we still defer to the wealthy in a lot of things. It's not necessarily smart, but it's where we wound up."
] | [
12
] | [
[],
[]
] | [
"url"
] | [
"url"
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|
gcprwb | What dictates the maximum framerate of a PC game? | Let's say my character has a specific animation that lasts exactly 1 second. was that animation not made frame-by-frame? In which case the whole animation is comprised of (for example) exactly 120 frames that play over one second. If I run the game at 60fps then it makes sense that the animation will skip every other frame. But if I run it at 240fps will it just "add" artificial frames? Thanks for helping me understand this better! | Technology | explainlikeimfive | [
"fpcr316",
"fpcqkle"
] | [
"Animations these days aren't made frame by frame, they are made with keyframes. A keyframe is a specific pose that has been made by an animator, or obtained from motion capture. Keyframes may occur at regular intervals, or they may be irregular times. When the game plays the animation it interpolates between key frames. So say an animation was authored at 30 keyframes a second, but the game is running at 60 fps it means every other frame the animation will be half way between two keyframes. The basics of interpolation are pretty simple. Imagine in one keyframe a character's arm is out straight, and in the next the elbow is bent 90 degrees. If a game's frame happens at the half way point between those two keyframes then the elbow will be bent 45 degrees. There are more advanced ways to do interpolation, but the principle is the same."
] | [
7
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
a192oz | Why Venezuela is collapsing since they're an oil rich nation; what went wrong? | A little depth to the answers, not just "***because, socialism*** please. | Economics | explainlikeimfive | [
"eanqv16",
"eansniv",
"eansr5e"
] | [
"A couple of reasons. Firstly, they relied far too heavily on oil. Before the collapse, oil made up 95% of exports. When oil prices came tumbling down due to US shale, the foundation for their economy was eroded away. Another problem was the appropriating of private assets by the government. Entire businesses were seized, and a government puppet was put in charge. Needless to say, they had no idea how to run a competitive company but could rely on government wealth to keep them running. Yet another problem was the government’s response to these problems. When their income from oil started running dry, they doubled down and threw more subsidies at the oil industry. In fact at the current prices, a single US dollar is enough to fill up your car 700 times. That is obviously absurd. In order to pay for these subsidies, the government had to print more money since they couldn’t afford it in the budget. This led to hyperinflation and the huge crisis we have today. To combat hyperinflation, the government decided to use price controls. While it technically succeeded since no shops could sell goods at increased prices, it had the obvious side effect that shops had to make a massive loss for every sale and thus closed, leading to mass shortages of every item."
] | [
20
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
jhxdzw | How does a natural food like honey never expire, unlike other natural foods like fruits or vegetables? | Chemistry | explainlikeimfive | [
"ga2sz61",
"ga2soze"
] | [
"It's not necessarily that honey is natural and fruit are unnatural. It has more to do with the moisture content. Food goes bad when bacteria starts growing in the food and begins to leave behind nasty byproducts that make the food inedible. This is normally fueled by the presence of water Sunlight is another way that food becomes spoiled and that's driven by the decay of compounds through UV light. In contrast, honey almost has no water which leads to a very hostile environment for bacteria. If a bacterium is able to start growing, the honey will quite literally suck the moisture out of it through osmosis, effectively killing it. Honey is also known to have a number of antibacterial compounds in it which also inhibits bacterial growth. Additionally, the acidity of honey is not ideal for bacterial growth."
] | [
11
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
|
b4kwpe | how do plants remove toxins from the air? | Biology | explainlikeimfive | [
"ej7cljf"
] | [
"Plants specifically remove carbon dioxide from the air through a process called photosynthesis. Although it's a complicated word, photosynthesis is just the plant version of how we humans breath (admittedly, it's more the plant version of how our individual cells breathe, but it's fine) When a human breathes, their lungs take some oxygen from the air to fuel their body, and puts some carbon dioxide into the air. When a plant 'breathes', it takes some carbon dioxide from the air to fuel itself, and puts some oxygen into the air. This oxygen is good for us humans because we need oxygen to live, and the removal of the carbon dioxide is also good because in high amounts, it can be dangerous to us. I'm not familiar with plants removing any other toxins, so I'm sorry if I accidentally answered the wrong question. Edit: plants, not pants"
] | [
4
] | [
[]
] | [
"url"
] | [
"url"
] |
|
egwcff | How are DVDs/Blu-Rays/VHS’s converted to 4K? | Other | explainlikeimfive | [
"fcaeqiy",
"fcak53v"
] | [
"Movies are always shot in a higher resolution than they are released in, for movies shot on film they just scan in 4K the original film, and newer films that were already shot in a higher resolution, so get that version"
] | [
4
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
|
fl3r6h | What exactly happens to your brain (psychologically)when you learn a second language? | Biology | explainlikeimfive | [
"fkwleck"
] | [
"The same thing that happens when you learn anything else. [Neurons that fire together wire together.]( URL_0 ) (Sorry, I realize this is not a good enough answer for this sub, but that link might help you if you don't get a better reply.)"
] | [
6
] | [
[
"https://en.m.wikipedia.org/wiki/Neuroplasticity"
]
] | [
"url"
] | [
"url"
] |
|
c5w2v7 | Why does the engine of a vehicle only require around 1-3 thousand rpm other than for accelerating? | For example riding at a constant 65 in my truck only requires 1.5k rpm, riding at 30 is the same. So why wouldn't you get substantially higher gas mileage on a long stretch going 60 vs going 30? Is the engine doing more work somehow? If so, how? | Engineering | explainlikeimfive | [
"es4g0r1"
] | [
"You do get better gas mileage at 60 for precisely that reason. The ‘how’ it does it is because of the transmission and the gear your vehicle is in."
] | [
7
] | [
[]
] | [
"url"
] | [
"url"
] |
diy3nq | Why does squinting helps with vision? | Biology | explainlikeimfive | [
"f3zjj9g"
] | [
"It flexes muscles which control the eyeballs causing the eyeballs shape to change temporarily. Changing the shape of the eyeball changes the focal point which can slightly improve vision. Though it depends on the type of issue being corrected. Could also make your vision worse."
] | [
3
] | [
[]
] | [
"url"
] | [
"url"
] |
|
c83ec9 | Why did humans develop the cold shock response? | Humans automatically hyperventilate when they are exposed to very cold waters. In fact, the "cold shock response" is the leading cause of death for immersion in cold water. Why and how did we develop this as humans? Wouldn't a response like this decrease fitness and be harmful? | Biology | explainlikeimfive | [
"esjxsk4",
"esjwxqj",
"eskmz89"
] | [
"Strangely enough, the shock reflex is not the full story. There is also the diving reflex—when a vertebrate’s face gets wet, their heart rate slows, breath slows, and blood is shunted to brain and organs and away from extremities. The point is there are a variety of reflexes—quick inhalation of oxygen in anticipation of not having enough, flowed by conservation of oxygen. The combination has evolutionarily proven to be the best chance of survival, even though in some circumstances it isn’t the best."
] | [
29
] | [
[],
[],
[]
] | [
"url"
] | [
"url"
] |
b3fzkd | What causes the ‘warm’ feeling in the stomach when one consumes whiskey or other alcohol? | Biology | explainlikeimfive | [
"eizajg2"
] | [
"When alcohol comes into contact with your mucous membrane (the tissue that lines your mouth, throat, and stomach), the alcohol has an effect on your nerve cells that detect temperature, making them more sensitive to heat. Normally, you can't feel your body heat, because your nerves ignore it, and only detect changes from that temperature. The \"warmth\" or even \"burning\" sensation that you feel in your mouth when you drink alcohol is actually you feeling the heat from your own body, which your nerve endings normally ignore. On another note, you also feel warm on the outside from drinking alcohol. This is because when alcohol gets into your bloodstream, it causes your blood vessels to dilate, which in turn causing your warm blood to move closer to the surface of your skin, where all your nerve endings are. So again, you are just feeling your own body heat that you normally ignore."
] | [
17
] | [
[]
] | [
"url"
] | [
"url"
] |
|
aydkty | What exactly is a good/high/fast metabolism? | So I am a skinny guy and always get things like 'You're so lucky to have a good Metabolism and you can eat what you want.' And that's true but I asked myself what exactly that means? As a kid I always thought it meant I have to go to the toilette more often ( if you know what I mean ) but that is not right. So what exactly does my body do that makes my metabolism good? And what does having one really mean? | Biology | explainlikeimfive | [
"ei01vkm",
"ei0fc8i",
"ehzxw73"
] | [
"The actual efficiency of your gut doesn't vary between individuals as much as some people would like to think. A more in-depth answer from another user here: [ URL_0 ]( URL_1 )"
] | [
12
] | [
[
"https://www.reddit.com/r/askfatlogic/comments/6pni4w/so\\_is\\_the\\_whole\\_fastslow\\_metabolism\\_a\\_myth/dkqss1f",
"https://www.reddit.com/r/askfatlogic/comments/6pni4w/so_is_the_whole_fastslow_metabolism_a_myth/dkqss1f"
],
[],
[]
] | [
"url"
] | [
"url"
] |
f2l86n | What is Aliasing? | Basically I was wondering what is aliasing and how does changing the sampling rate of the signal effect aliasing? | Technology | explainlikeimfive | [
"fhddgyq",
"fhdd02v"
] | [
"I'm not an expert on this, but I'll try to explain it. Aliasing is when you misidentify a signal and get distortion. When your sample rate is to low, you don't get a complete picture of what the signal looks like. Let's look at a sine wave to make it easy. You need to measure the signal several time per cycle to be able to identify it (i believe you need at least two points). If you don't measure fast enough, you can miss the peak (or even several) and catch other parts of the wave thinking it's before a peak. [Here's what that looks like]( URL_0 ). The end result in this case is that the frequency you see is slower than what you actually have. There's a special case where your sample frequency is the exact same as the signal frequency. You always see the same part of the wave so it doesn't actually look like there's a signal at all."
] | [
6
] | [
[
"https://images.app.goo.gl/N7f6VttHbcfzXMd76"
],
[]
] | [
"url"
] | [
"url"
] |
oazv4s | How can geometry produce vibrations or vibrations produce geometry? | I've seen some videos of a vibrating table with sand on top and trying diffrrent frequencies like 400hz, 700hz and the sand makes some geometric patterns. | Physics | explainlikeimfive | [
"h3kp46n",
"h3kpf0o"
] | [
"the sheet vibrates in what is called \"eigenmodes\". it wobbles more or less like a two-dimensional spring system. Some locations are near rest, called \"nodes\", and this is where the sand accumulates. The eigenmodes (and thus node structure) depends on the shape of the sheet and the frequency. Higher frequencies usually mean more/denser nodes. The shapes are symmetric as the sheet is symmetric."
] | [
4
] | [
[],
[]
] | [
"url"
] | [
"url"
] |
kf1me6 | If mRNA vaccines can get through the cell wall, what's stopping them from getting through the nuclear wall and changing our DNA? | Asking for a conspiracy theorist friend. I'm pretty sure I understand the gist of how mRNA vaccines work, but she's worried they're going to mutate our DNA in addition to what they're supposed to do. | Biology | explainlikeimfive | [
"gg5x9cq"
] | [
"Know what else introduces RNA to cell that alters the DNA locally? Viruses"
] | [
5
] | [
[]
] | [
"url"
] | [
"url"
] |
ijqt4x | How can humans tell which side they are facing? Like a gyroscope always being able to tell which side it’s on. | Biology | explainlikeimfive | [
"g3fkcmr",
"g3fvhbf"
] | [
"There is a little pocket of fluid/air in your ears, and your brain tells which way is down by how that fluid is resting. (Like how the water always sits on the bottom of a half empty water bottle no matter how you turn it)"
] | [
11
] | [
[],
[]
] | [
"url"
] | [
"url"
] |