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kzhwm3
|
why ten year olds can brush off injuries but adults take several days to recover from the same injuries?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjnwqiz",
"gjonzsf",
"gjoqwax"
],
"text": [
"different factors, for one due to their body being younger it can sustain more visible damage that actually isn't that bad, than theres also the fact that their bodies are usually in better physical shape in general and lasty: They are growing, if they can increase their body sizes yearly by that much than healing some wound is just some side project that is easily done.",
"Me at 10: Falls off bike at high speeds into gravel. All scrapped up but gets back on bike and forgets about it until I get home and mom freaks out. Me at 30: Lightly stubs toe on coffee table. In hospital for three days with internal injuries. Drafted final version of last will and testament. Everything goes to my cat, Mr. Yippers. Dies alone.",
"Just wait until you get even older and instead of taking a few days to recover things just never recover."
],
"score": [
13,
7,
4
],
"text_urls": [
[],
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|
[
"url"
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[
"url"
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|
kzi7u0
|
For medicine/vitamins that come in pill format, where the dosage is more than one pill, why are the pills not just made bigger so that the dosage is just 1? Would it not also be cheaper that way?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjnyog4"
],
"text": [
"The dosage is customized to the patient. It's just a lot easier to make a standard size and then have certain patients take multiples - especially with the most obscure medications. Where you should really get annoyed is with the prescriptions that call for *half* a pill since this requires a pill cutter (and oval pills don't generally work in pill cutters)."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzibul
|
Why is inflation such a bad thing?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjnzg5h"
],
"text": [
"Major issue is currency keeping up to par with income. In the US especially, it is a wide margin. We grew up with stories of our parents and grandparents making $1.95 an hour, but standards of inflation equates that to roughly $17 depending on the year (I was going off of my parents). Currently in the US, minimum wage is $7.25 an hour. The older generations wonder why we can't live as flavorently as they did, but they don't see the actuality of inflation disparity."
],
"score": [
6
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
kziho9
|
How do Rancher, Docker & Kubernetes work together?
|
I just learned about these pieces of software while doing some research for my new home network. It makes me feel not very smart. Please - ELI5
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjob2jt"
],
"text": [
"Docker - creates containers in which applications can run. A container is like a lightweight Virtual Machine; rather than sharing one physical machine with multiple VM instances (which each require their own Operating System), you're sharing one single OS kernel with multiple container environments. Kubernetes - orchestrates containers. Allows you to easily manage multiple containers across multiple machines, including automating the creation/destruction of them. For example if you want to run a cluster of Docker images that automatically scales based on load, Kubernetes could do this. Rancher - adds a nice GUI on top of Kubernetes and simplifies the installation and creation of Kubernetes clusters."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzinzz
|
How do kids grow out of allergies/lactose intolerance?
|
When I was a kid, I was severely lactose intolerant. So much so that I would break out in hives. I grew out of it by about 6ish years old, and now I drink a glass or two a day. How is that possible??
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjo1q1s"
],
"text": [
"In your case, you ended up cultivating the proper bacteria in your gut; species that come with their own equipment to break down the milk sugar, *lactose,* that your body doesn't have, or doesn't have enough of, naturally."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzitpl
|
; How does tearing a muscle while working out suddenly give it space to regenerate and make MORE muscle. Why do muscles get bigger?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjo3vaj",
"gjod03q"
],
"text": [
"You do not increase the number of tissues in your muscles. Instead, when you exercise a muscle a random selection of fibers in that muscle break down (but do not disappear). Depending on the extent of effort a varying number will do so. Afterward, those muscle fibers will rebuild and will be a bit larger. Depending on the energy source for the muscular effort there may be some soreness. This is why most training varies from day to day emphasizing different muscle groups. It's better to allow muscles to rebuild while they're (comparatively) resting. Thus, more frequent break-down and rebuilding event will cause muscles fibers to get bigger and bigger each cycle.",
"Muscles \"grow\" through two types of hypertrophy: sarcoplasmic and myofibrillar. You never really increase the number of muscle fibers. That number always stays the same. What changes are the characteristics of the fibers that you already have. Basically, exercise induces microtrauma/microtears in these fibers. Like most other cells, when there is damage, your body will seek to repair the damage in a way that will prevent future damage. With exercise, your muscles will repair themselves to be ever so slightly stronger to prevent future exercise from hurting you. This type of hypertrophy is called \"myofibrillar\" hypertrophy, where you grow more contractile proteins (sarcomeric actin and myosin). Your muscles become stronger and much denser (thicker). This is predominant in power athletes (e.g. powerlifters, olympic weightlifters, etc). Alternatively, sarcoplasmic hypertrophy is induced in a similar manner. However, this type of muscle growth is usually due to an increase in the size of the cells themselves. You increase the volume of the cells generally because you need to accommodate for greater energy production (mitochondria) and stores. Your muscles become much larger and can work under resistance for longer. This is predominant in bodybuilding. These two forms of muscle growth occur at the same time and are very rarely independent."
],
"score": [
32,
4
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
kziuqg
|
What are those dust motes we see floating around made of? How do they form?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gjo393b"
],
"text": [
"Most of the dust particles that you see wafting around in the sun are organic. These come from plants or animals that have dried out and can break down into smaller and smaller pieces over time. Because these eventually very tiny bits are usually not made out of heavy atoms like the kind that are in rocks and stuff, dust from organic sources is often very light, and so it pretty much floats given the lightest whiff or current of air. Humans and their hairy pets produce a lot of dead flakes of skin and tiny bits of hair that really can contribute to household dust. The next time you have a thin sliver of sunlight coming into where you live, some of the bits that are floating around in there... are very likely yours."
],
"score": [
12
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
kzj48m
|
How do food companies figure out when that food expires?
|
also which flair would this apply to
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjoe0wy",
"gjofvnh",
"gjojof6"
],
"text": [
"Very cynical comment from the other poster. The less late-capitalist-dystopian answer is that food companies just know by experience; that's to say, testing in conditions that customers are expected to store their products in. They can leave milk in a refrigerator and sample it every now and then, and once it goes bad beyond a) limits set by food safety laws and/or b) what they consider the minimum quality for their brand, that's the expiry date. Repeat enough times with enough milk samples and you'll get a statistically accurate picture how long the product stays good. Add in a bit of safety margin and you're all set.",
"I worked for a food production factory that did organic & processed soups. The company had products on the shelves for years when I worked for them, and had an establish quality control team to take samples & run tests on *very old* soups. They'd take a solid 30-50 packages out of a run of thousands, so it was no real loss to the company or the customer. Every 6 months or so they'd go through the stock of samples and test them. Generally speaking, as long the the package's seal was intact, the food was edible. Beyond that it was down to an issue of quality, and brand, like Campbells wouldn't want dissolved noodle paste in 2+ year old chicken noodle soup, even if it *was* edible. And most of the products we made stuck with that 2 year expiration limit as a baseline. There weren't too many products that strayed from that, mostly due to the *quality* of the soup, even if it was technically edible up to 5 years after. Most of it comes down to the seal on the packaging, or otherwise the packaging & processing design itself. Something like ground beef only has a few days because your super market is only covering it with a layer of plastic. Something like a can of soup is pretty much good for decades or unless the packaging is dented/the seal is compromised.",
"For very fast perishable. literally having a couple product placed in a observable place and record mean time to expire. For shelf stable food items that takes years to expire, most company start with a baseline expiry date (usually 2 years) where its guarantied to not expire. Then set up a observable sample to fine tune it."
],
"score": [
24,
13,
4
],
"text_urls": [
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|
[
"url"
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[
"url"
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kzj6mi
|
Are calories from drinking processed the same as calories from food? How are some heavy drinkers thin?
|
Pretty much the title. Is 1000 calories from food processed the same way as 1000 calories from beer? Do you absorb all of the calories in both or does your body reach a maximum capacity of calories before it "throws out" the rest?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjo87w4",
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],
"text": [
"“Heavy drinkers” may appear “thin” because they tend to lack a balanced diet and often lack essential dietary vitamins, which prevents proper absorption of other essential nutrients. Notable dietary deficiencies tend to be folic acid, thiamine (vit b12), magnesium. They also can be chronically mildly dehydrated. There are myriad of symptoms related to these deficiencies; thin or brittle nails and hair, headaches, fatigue, pale skin, dry skin, poor circulation, anemia, heart palpitations, arrhythmias... obviously a non-exhaustive list. If you have ever heard of an alcoholic getting a “banana bag” IV hung, either for detox treatment or as a precaution if one is ever admitted to the hospital, it is just these essential vitamins and saline. Other precautions usually include a mild benzodiazepine to prevent detox seizures.",
"I don’t think the form that the calories come in (solid or liquid) will affect how your body absorbs them. But different foods do get absorbed differently. Sugar is absorbed and processed faster in your body than fat. So you absorbed more of the calories as the food passes through you when it’s from high sugar. When you eat fats and high fiber foods, it takes longer for your body to break it down and absorb it, so you end up passing the food without absorbing all of the calories. At least that’s my understanding."
],
"score": [
6,
3
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"text_urls": [
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|
[
"url"
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[
"url"
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kzjmp7
|
Why an RX 6800 graphics card uses 12gb VRAM when playing Warzone, but a 3070 would run the game fine with only 8gb Vram?
|
As the title reads. My amd RX 6800 graphics card uses 12 - 13gb of vram when playing Warzone and other games. How would a 3070 or a 3080 for that matter with only 8gb or 10gb VRAM run the game in similar or better performance? Does the VRAM not really matter?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjoakut"
],
"text": [
"Most likely the game detects what size vram you have and loads everything it can into it, which would look like you need more vram but it's just basically cramming more into it because it can.. Think of it like you are planning 2 vacations you have a choice between a smaller suitcase and a larger one. The smaller one is big enough to fit one vacation with of stuff in, but you would need to repack between vacations. The bigger suitcase had enough space to fit both vacations. It's not a perfect metaphor as the vram is constantly being loaded and unloaded depending on what you do in game. More in all likelihood, when if you had 20gb of cram the game would saturate that too. While in reality the vram is so fast, you realistically only need 3 or 4 gb to never notice a difference."
],
"score": [
3
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
kzjtli
|
why is it so easy to go cross eyed but so hard to make you eyes look in the opposite direction?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjo8tr3",
"gjob801"
],
"text": [
"Your eyes are meant to cross. They will basically always be crossed, more so when the object you're looking at gets closer. Under no natural context are your eyes meant to point in opposite directions.",
"When you go cross eyed you are focusing your eyes on one thing and that's what they are good at the one thing is just close by. Having your eyes look in opposite directions isnt beneficial to you because your brain cant connect the fis to make a picture in your head that makes any sense so your eyes don't do that"
],
"score": [
15,
3
],
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|
[
"url"
] |
[
"url"
] |
|
kzk557
|
Why is fresh saliva out of the gland liquid but becomes instantly thicker once it's in the mouth?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjob8ul"
],
"text": [
"Fresh saliva is made up of water, mucus, salt, and other trace minerals. Water being by far the main component. When it leaves your gland, much of the water absorbs into your skin (gums, tongue, lips etc) to keep it wet, and since water IS the liquid, your saliva becomes thicker. It's why your saliva is very thick when you're thirsty."
],
"score": [
3
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
kzkf88
|
How will the journalists who entered the Capitol for press get away from being prosecuted and indicted for trespassing?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjod67p"
],
"text": [
"There is no exemption for journalists. If law enforcement officials want to charge them with trespassing during the course of their investigative duties, then they will. It's entirely possible that officials will *choose* not to charge journalists, but that's their decision to make."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzkfrd
|
Why are ski mountains groomed with a groove pattern opposed to something flat?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjocqv9",
"gjorg9o",
"gjp5zl5"
],
"text": [
"If they groomed it smooth, it would melt and refreeze smooth, and you'd get an inclined ice skating rink, which is no fun to ski on. With the grooves, it melts and refreezes unevenly, meaning it likely to break up when the ski edges dig in. Which is more fun to ski on.",
"If it gets packed down completely flat, you’re essentially using a zamboni and the slope will freeze into a big ice rink. Skis can’t gain traction on ice. The ridges create a surface ski edges can dig into, and keeps the slope from freezing so that skiers can turn and stop without falling and slipping",
"It also helps the skiier with depth perception vs a smooth slope that can get very reflective."
],
"score": [
77,
22,
7
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"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
kzkhkp
|
how come a split atom will release so much energy?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjocxf5",
"gjofwxy"
],
"text": [
"A lot of energy is tied up keeping the nucleus together, it's called the strong nuclear force. Splitting the atom releases all this energy.",
"All the reactions we're used to in terrestrial life on earth are the interactions of atoms, which are based entirely on electrons on the outside of atoms interacting with electrons on other atoms. The fundamental force of nature involved in this is the electromagnetic force. Everything, even really energetic stuff like gunpowder or explosives or regular rocket engines, is releasing energy stored in rearranging electrical bonds between atoms. None of it does anything to rearrange the atomic nucleus itself. The nucleus is held together by a whole other force, called the strong force. It's about 100 times stronger than the electromagnetic force and can react \\*much\\* faster. When we split an atom, we're \"breaking\" strong force bonds. These hold an insanely larger amount of energy than we're used to in regular chemical reactions. It's, literally, a whole other realm of physics."
],
"score": [
11,
8
],
"text_urls": [
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
kzkj1m
|
How do universal remotes work
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjodjtf",
"gjodf2p"
],
"text": [
"Typically they have an IR sensor, you put it in programming mode, push that button you want on the original remote and it records the pattern of flashes. Some also have a lot of the signals for major appliances preinstalled.",
"They store the patterns for tons of devices and let the user either cycle through them or enter codes to activate them. It’ll continue using that set of patterns until programmed otherwise. I had a remote in the 90s that had an IR receiver on one and and you could program that remote either by cycling through the codes or by actually using a current remote and it’d detect the patterns. It was also voice activated which was neat when it worked."
],
"score": [
4,
4
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
kzkqwf
|
Why do minor chords make us feel negative emotions and major chords positive?
|
It can’t just be that we associate these sounds with these feelings, a minor chord innately makes us feel sad or angry.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjotg7x"
],
"text": [
"Much of it is context. A single minor chord probably isn't as impactful as a song with sad lyrics in a minor key. Listen to Moondance by Van Morrison for an example of a song in a minor key that doesn't really sound sad/negative. Beyond that, the root/tonic and third notes of a minor scale are closer than the tonic and third of a major scale. The closer two notes are together, the more dissonance or tension we hear."
],
"score": [
4
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
kzkyqc
|
What's the difference between a real Mona Lisa and a replica made with machines and computers that can copy the original in every single aspect?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjon2fa",
"gjogk6s",
"gjot0at",
"gjp0m2v",
"gjosqk1"
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"text": [
"That's an issue with counterfeit currency. If you can perfectly simulate something, it's real. But 15th century paint can't be simulated because of all the radiation around since the 1950s.",
"Only about 500 years and the fact that it was painted by Leonardo davinci..... other than that they would be about the same I guess.....lol..... oh and the fact that the real one is absolutely priceless!",
"You can only program what you already know to program. So, perhaps the surface could be replicated, but the underlying layers can not be (at least yet). This means that any subtle coloration from the underlying paint may not be visible, or the canvas was reused and some of the original “appears” on the visible surface(as texture or something else). In short, one can not fully replicate an original.",
"On a molecular level there are certainly differences (materials, etc.) but I don't think that's what you're asking. From the perspective of art subjectivity, there isn't a difference. If you took an unknown piece of art and showed it to people and they didn't know if they were looking at the original or a print, they would like it or dislike it entirely based on their preferences. We place a psychological value on an original piece, though, which is entirely unrelated to the quality of the art itself. This is something that is part of human emotion and behavior and is deeper than art (perceived worth is present in many, many areas of life, like buying a brand name for example) and is somewhat outside the scope of your question and simultaneously my ability to explain.",
"The replica is not a piece of history which is what you are buying with the real piece. It is possible to tell the two apart with analysis of the aged pigments and radiation and a whole bunch of other stuff. Essentially, the replica doesn't come with bragging rights."
],
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25,
8,
7,
6,
5
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|
[
"url"
] |
[
"url"
] |
|
kzl02i
|
What is prion?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjogxmd"
],
"text": [
"A protein that has been folded wrong and doesn't work. When it hits a protein that has been folded right, it refolds it to be folded the same wrong way it's folded, which means it can hit other right proteins and fold them wrong. It's dangerous because in most cases, to get rid of them you have to heat it up to the point where proteins break up, meaning all the other proteins break up, leaving you with nothing but a charred inedible mess. Regular cooking won't fix it."
],
"score": [
10
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
kzl2gi
|
Electricity.
|
My mother always unplugs appliances that aren’t being used bc they “waste electricity”; does this still ring true today, or are appliances updated & don’t waste as much? Obviously, the fridge, hot water heater and washer & dryer use the most power; how can I see which other things use the most power & is it worth it to still unplug them?
|
Physics
|
explainlikeimfive
|
{
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"gjogrfl",
"gjoi034",
"gjogr7x",
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"text": [
"Depends on the appliance. * Lighting: No, the switch completely disconnects it. A lamp does not need to be unplugged. * Motor devices: No, the switch completely disconnects it. Example, vacuum, blender. * Heating device: No, the switch completely disconnects it. Example, kettle, hair dryer. * Electronics: Yes, they have a power supply that produces the low voltage DC power they run on. Even if they use nothing, this power supply is still making DC power and consuming some electricity. Beyond this, they still often have varying degrees of rest modes rather than off. Your TV is waiting and watching for a TV remote signal for example. Example, TV, computer, phone charger, video game console. * Mixed devices, with any sort of electronic controls: Yes, these devices are a small computer paired with something else. The main part turns fully off by the computer, but the computer is still running. Example, an oven with its clock. A washing machine ready for you to hit a button. Etc. How much do these electronic devices draw? We're talking maybe up to $5 a year of electricity for a device, but you do have a lot of them. If you use the device daily, it might not be worth it. If you don't use the device for 16 months, might want to consider unplugging it.",
"It's a real thing, it's known as phantom electricity, or phantom loads. Sometimes this comes from a small flashing LED to show the device has power when powered off, or to sustain a device in a stand-by mode...like a game system or computer. It could lead to lower bills by unplugging everything, or switching off a power strip your devices are plugged in to....but unless you have a ton of stuff plugged in it probably won't lead to a noticeable decrease in your bill.",
"You don't have to take anyone's word for it. For this experiment, pick a day where there will be an average amount of electricity use. You'll need two days where the time of day, household use, and outside weather are almost the same. Plug everything in, go to the side of your house and take a meter reading (google instructions if you need them). Then, after, like, four to six hours or so, go take the meter reading again. This will tell you exactly what you used for that block of time. The next day, unplug everything. Go out at the *exact same time*, and take the first meter reading. Then, after the exact same amount of time passes as the previous day, go out and take the meter reading again. Compare the two days. If the difference is negligible, then your parents are wrong to unplug things. If the second reading DOES save lots of money (and the two days were pretty much equal), then your parents are right to unplug everything You might want to repeat the experiment a few times to eliminate as many variables as you can.",
"There are still a ton of devices which use electricity even when not turned on. You can verify this with a “kill a watt” meter. Most will use a very small amount of power URL_0 How critical it is that you unplug them is subject to opinion. URL_1 Average is about 50 cents worth of electricity per day ... $165 per year on average",
"Applicances that have a mechanical switch generally do not waste power because the switch disconnects them just as much as unplugging. Think the switch on the back of a computer power supply. Also toasters and Kitchenaid stand mixers. Toggle switches where on and off are the same physical position, anything with a clock or touch screen or remote control, are always on.",
"While power load is less than what it was, it is still a thing. We call this \"vampire load\" because even though the device is \"off\" it's still using electricity. We use it for things like maintaining a clock, providing enough power for memory, listening, or keeping a circuit closed for \"waking\" from a sleep or idle state. It has to be somewhat \"on\" to even listen to turn fully on. Think of it like being asleep. Your body has to keep doing some things on to you know, not die. That low consumption is your \"vampire load.\" If you fully unplug from the wall, a doctor has to use the paddles to \"plug you back in.\" But ideally we are always plugged in so there will always be a small draw. Though we have less power consumption in 2020, we do have more devices that require that vampire load to power passive features. Edit; Every device tells you it's draw so you can decide if your power bill can take it."
],
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76,
16,
8,
7,
6,
4
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[],
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[
"https://money.howstuffworks.com/personal-finance/budgeting/how-much-save-unplugging-appliances.htm",
"https://www.nrdc.org/sites/default/files/home-idle-load-IP.pdf"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzl41k
|
Why is scar tissue so different than normal tissue?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjojf5h"
],
"text": [
"The purpose of scar tissue is to close your wound ASAP to prevent infection and to continue the healing process. It does this by skipping some steps of skin creation, mainly with the skin tissue and how it's aligned. Imagine you have to knit a scarf. You're given a week to do so, and all the tools and more are right there. Pretty easy right? You can even add some pretty patterns and make sure the scarf is warm and strong. This is how regular skin is made and replaces dead skin. Now imagine you're given three hours to do so, and only the bare minimum of tools are there. Chances are, it's not going to be a very good scarf, but it'll be a scarf, and should keep you warm enough to make another one. This is scar tissue."
],
"score": [
12
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzlbp0
|
Why does salt make everything taste more like itself?
|
or why does it "bring out the flavor" of everything?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjoih5t",
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"gjotutr",
"gjptlgh"
],
"text": [
"Salt is used as a universal flavor improver because at low concentrations it will reduce bitterness, but increase sweet, sour and umami, which is desirable for sweet recipes. But at higher concentrations it suppresses sweetness and enhances umami, which is good for savoury things. It’s also easily obtained in a pure form without any interfering flavors. URL_0 )",
"Here's what I learned from a big science article. We don't understand all the reasons why salt enhances taste, but we have a few theories, one of which is basically proven. The most proven one is this: Salt decreases bitterness. Salt is made of sodium and chlorine, which can readily dissolve into sodium ions and chlorine ions in water. Taste buds detect different flavors by binding to food molecules, and different taste buds detect different flavors. (Turns out this isn't true. See final edit.) For example, there is a type of taste bud that senses bitterness. Sodium ions are able to bind to the parts of the food molecules that would connect to your bitter taste buds. This stops those bitter food molecules from binding to your taste buds, which stops you from tasting them. That's why recipes for sweets usually call for a little salt. You only need to add enough salt to saturate all the bitter molecules. If you add more than that, you'll just make the food taste saltier. The less proven theories are these: Salt may make liquids feel thicker by stimulating mechanical sensors in our tongue and mouth. Salt may decrease a property of food called \"water activity.\" Many foods contain flavor molecules mixed in liquid water. Water has a property called \"partial vapor pressure\". Higher pressures effectively distance flavorful molecules, making them less dense. There's no way to ELI5 here, but think of a balloon. Air at higher pressure will expand the balloon to a larger volume. Larger volume means lower density. Thus, higher water activity (partial vapor pressure) means the flavors in a food will be less dense, and therefore less flavorful. Partial vapor pressure is equivalent to the pressure of a liquid at a given temperature times the amount of that liquid in the volume (measured in % moles, molarity). But when salt is dissolved in water, its ions interact with water molecules, removing them from that equation. Thus, the partial vapor pressure drops, and the density of the flavor molecules increases, enhancing flavor. For a reason the article did not explain, this also has the effect of increasing the \"volatility\" of those flavor molecules. Volatility \"describes how easily a substance will vaporize.\" Basically, it turns some of those flavor molecules into a gas, which allows them to enter your nose and be smelled, further enhancing the overall flavor. [ URL_0 ]( URL_0 ) Edit - Some edits, because I didn't know things I really ought to. Edit - Thanks for the Silver!!! Edit - Turns out I was wrong about different taste buds responding to different flavors. All taste buds can taste all flavors. The idea that different parts of the tongue respond to different chemicals is an outdated myth that I learned in school and so took for granted when I was writing my post. Thank you to u/stefek132 for pointing this out!",
"I hope I’m paraphrasing Alton Brown correctly. I think that salt is supposed to basically open up your taste receptors. This will naturally enhance the flavor of what your eating, even something sweet. A little bit of salt will enhance sweet flavors rather than make your dessert taste salty.",
"Here's my theory. Nerve cells work by a electrical current being propagated by the movement of charged ions across the cell membrane. A salty environment provides plentiful sodium and chloride ions to help propagate nerve impulses. Taste cells are connected to sensory nerve cells. In the presence of high concentrations of sodium and chloride ions, they are at maximal excitability, therefore amplifying the neuronal response to a taste cell activation."
],
"score": [
335,
75,
11,
5
],
"text_urls": [
[
"https://www.sciencefocus.com/science/why-does-salt-enhance-flavour/"
],
[
"https://www.ncbi.nlm.nih.gov/books/NBK50958/"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzlhgs
|
Is buying a lottery ticket a good bet if the jackpot is high? Why or why not?
|
I have a family member that makes the point that, when the jackpot is really high it's worth it to buy a ticket. "Even if you only match 5 out of 6 number you still get millon(s)." And also, "You can't win if you don't play." And, "SOMEONE has to win." Does a high jackpot make it a good bet it is it still essential throwing your money away? Why?
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"gjojfwh",
"gjokbtm",
"gjokeet"
],
"text": [
"Your odds of winning are exactly the same. People just get excited about the big jackpots. The odds of multiple winners increase, because more people play. But your odds of hitting the jackpot stays the same regardless of the amount.",
"Mathematically, it does become a good bet on large jackpots. The odds of winning the jackpot are 1 in 292million; therefore, it becomes a marginally “good bet” to risk $2 on a ticket when the jackpot goes over roughly $600 million. A problem to factor in is that the lump sum payout is far less than the published jackpot amount (which is a 20 year installment), so statistically it’s still not a good bet even at $600million.",
"There have been situation where a lottery is actually +EV, meaning it makes sense to play. These situations are pretty rare. One is when the rules of the lottery are such that the EV of each ticket changes in your favor enough to be positive as less ticket are available. This can happen with scratch offs and there are people who have taken advantage of this in the past. The second is when a jackpot gets really high. If there are 300 million possible winning combinations and each ticket is $2 then once the total price is greater than 600 million it becomes +EV. Due to taxes this number needs to be over a billion for things like mega millions and powerball."
],
"score": [
5,
4,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzlkib
|
Why do old cartoons and shows have those little white and black dots pop up randomly?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjolgjo"
],
"text": [
"If you’re not talking about regular old dust and scratches on old film, you might be referring to those big black dots that sometimes flash at the upper right of the screen. These are called cue marks, and they’re a signal to the projectionist at the theatre that the film reel is about to end and they need to switch to another reel soon. An entire movie can’t fit on one reel of physical film; in a theatre, there’s actually two projectors in the booth and the projectionist’s job is to switch between the two seamlessly at the exact right moment. The reason we see them on video sometimes is usually because the video copy is sourced from a film reel meant for use in a theatre, which are sometimes the only available copy (a lot of older films just weren’t archived properly, and *really* old films were often printed onto a kind of film that loved to catch on fire in storage)."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzls99
|
Do we actually know how big space is; how? How do we know and how do we know we’re right?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjoljma"
],
"text": [
"No, we don't know. We know it's at least as big as we can see (which is about 30 billion light years if the universe follows the same laws of physics everywhere, at least 14 billion light years if at least light travels at a constant speed). It's entirely possible that it's infinite, and there are some reasons to think it is, but we have no way of testing that within our current understanding of physics. We don't know we're right, but if we're wrong then certain theories of physics are also wrong and we can test many of those by experiment. So far, no experiment has turned up data that refutes our current understanding of size but it certainly could in the future."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzlurr
|
Can holding down the power button on your PC/laptop to switch it off actually damage it? If so, how?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjolx6b",
"gjomidz",
"gjom1ba",
"gjp4axq",
"gjp0c2z"
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"text": [
"Can result in data loss, possible os/file corruption because you're forcing it to power off rather than a graceful shutdown. Files could be in the process of being written. But on the odd occasion if it's frozen, that's not really a big concern. But if you're doing it on a regular basis...shit it down properly. That's why that option is there.",
"Well, in the days of ye old Windows 95 or older, that was true. You see, the whole reason that a \"shutdown\" procedure existed (It is now safe to turn off your computer) is because just cold-stopping power flow could cause surges or damage fragile electronic parts. What changed? Well, the actual power button changed. One: To an actual button instead of a switch, and two: the function of the \"power button\" changed. It went from acting like a light switch that just breaks a circuit to being a signaller that tells your computer to start powering down itself safely and THEN power off Nowadays we call that an APCI, and it's also why you can choose options like \"sleep\" or \"restart\" from just tapping the power button (usually).",
"It can't physically damage it, but if data is in the process of being written it might be corrupted.",
"There's a simple chef analogy that works quite well. Imagine your computer is a head chef coming to the end of the work day. Assuming the restaurant closes on time he and his team has time to clean up, wash dishes, dry dishes, stack dishes back into cupboards, scrape scraps into the bin, chuck the tea towels and chucks cloths into the wash etc. Then the next day when the restaurant opens again everything is neat, clean and placed where it is supposed to be. Now imagine that instead of that the restaurant simply closed abruptly during peak hour and forced the team to go home without cleanup. The kitchen is an absolute mess, nothing is neat, nothing is orderly, things get misplaced, things might get broken. That is essentially your cpu, ram, hard drive etc.",
"Holding down the power button on a modern PC or laptop (made in the last 15-20 years) will not meaningfully damage the hardware itself. The hardware itself will work just fine next time it powers on. The data in the PC will *usually* be fine as well, however it may get damaged (corrupted) instead. There are a few reasons why, here are a few: - Writing (Saving or copying) data: When power is suddenly interrupted, the incomplete written data is unusable. It often can't be salvaged, in which case it has to be deleted. - Storing temporary data in RAM: Any data in RAM is almost immediately lost when power is removed. So, if an operation is, for whatever reason, using the RAM, on restore the data in the RAM is lost, which could result in an incomplete (and therefore corrupt) set of data depending on what was being done. In either case, only the data is damaged and not the actual PC itself. If the data wasn't important anyways, the data can simply be wiped and reset and the PC will function as though nothing happened."
],
"score": [
25,
9,
7,
3,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzmgnn
|
How do people beyond the great tree line up north; places like Nunavut and Greenland get oxygen to breath?
|
Here’s a link[link]( URL_0 ) if you don’t know what the great tree line is
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gjoqrxx",
"gjopd6v",
"gjopdpj",
"gjot7g4"
],
"text": [
"Most oxygen doesn't come from trees, but even if it did, the Earth's atmosphere mixes thoroughly over timescales of a few years to decades. The amount of oxygen in the air (as a %) is essentially the same everywhere on Earth and up to a very high altitude, much higher than the highest mountains.",
"Most of the earth’s oxygen comes from the ocean, not trees. Which is part of why it’s so important to keep our water healthy. More info [here.]( URL_0 )",
"Literally the air doesn't just stay in one area it does move around eg wind. The air expands and contracts and mixes.",
"Air moves around. That's also how people on ships don't suffocate, and how animals that don't live next to trees can live without dying."
],
"score": [
13,
10,
7,
5
],
"text_urls": [
[],
[
"https://earthsky.org/earth/how-much-do-oceans-add-to-worlds-oxygen"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzmqan
|
What happens to veins that are cut open during surgery? Do they connect back together? Do they close?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjp9y4j"
],
"text": [
"That depends: The veins of the skin and the fat below it, that you cut open to access the interior of the body, are either cauterized (burned with electricity to close them off) or closed by putting a knot on top of it. They most likely will grow again a little bit into the scar tissue, but smaller. I doubt they reconnect with their former other end. The veins of organs or part of organs, you want to extract from the body, are closed off, so they don't bleed into the body. The veins of organs you want to keep, but were accidentally or purposefully cut, are in my experience (and that is not much exp) never cut fully, but cut open partly. And if you want to keep them functionally, you have to stitch them together, which can be really difficult, because they are thin. In the worst case you'd have to use a prosthetic (an artificial vessel)."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzn1my
|
Why do bartenders mix drinks with ice then strain it out if they are going to add it to a glass already filled with ice anyway?
|
Why can’t they just use the ice from the shaker in the final drink?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjosv4s",
"gjozoxl"
],
"text": [
"The ice they use is not just for chilling the drink, it also helps to mix the ingredients together, like the ball in a can of paint.",
"The ice they mix it with helps to mix the ingredients and also quickly cool the liquors from room temperature (notice that the bottles are just stored on shelves in the room). They don't want the drink to quickly melt the ice in your glass, making a tepid, watery drink, so they chill it quickly with a larger volume of ice in a mixer and then the ice in your glass just helps it maintain a pleasant temperature from there."
],
"score": [
10,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzn31b
|
What is a mol?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjotbbp",
"gjots46",
"gjouzqn"
],
"text": [
"A dozen is a word that means 12 things, and a gross is a word for 144 things. A mol is 6.02214076x10^23 things. It’s used in chemistry to count the number of really tiny things, like atoms and molecules",
"It is 6.022 x 10^23 molecules of something. E.g a mole of carbon is 6.022 x 10^23 molecules of carbon. A mole of phosphorous is 6.022 x 10^23 molecules of phosphorous. However a mole of carbon will weigh less than a mole of phosphorus because molecules of phosphorous weigh more than carbon. You use moles in a similar way to using “dozen” E.g a dozen of eggs = 12 eggs. A dozen ostrich eggs are still a 12 eggs A dozen chicken eggs are still 12 eggs. The size of the molecule/egg will determine how much the mole/dozen will weigh. Note that you can use moles for compounds too. E.g a mole of water.",
"Oh boy these answers are all missing the most important point, so let drunk and in bed tyler explain. A mol is the number of molecules of a substance in a sample thats the weight of the number of grams represented by its atomic weight. One mol of hydrogen atoms weighs 1.001g or whatever, while one mol of cesium wiighs... hang on gota google it..132.9 grams. Cesium is heavier. So in 1.001 grams there is 1 mol of atoms hydrogen, and in 132 grams of cesium there is 1 mol of atoms. This is useful for approximating how many molecules need to go into a reaction, while still working in weights that make sense to us. If you wanted to have 1 mol (quantity) of any substance, you would add all the atomic weights together, and that number in grams would be the same number of atoms in that sample. (The number is expressed in every other answer here)"
],
"score": [
17,
8,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kznb5m
|
- Why does Inflation Occur? Is it Inevitable with our current economic system(USA)? Can't we just legislate it away(Assuming a semi controlled mixed market)?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjow6gr",
"gjow4q7"
],
"text": [
"Inflation happens because, while more money is being used, no more stuff is being made. In more economic terms, inflation is what happens when the money supply grows faster than the actual economy. If there's $5,000 and 5 cars, each car sells for $1,000. If there's $50,000 and 5 cars, each car sells for $10,000. In the latter scenario, the dollar itself is worth less because there is more of it. Overriding this with fixed prices causes products to be sold faster than they can be made. If store shelves are empty, money is worthless anyway. Inflation is intentionally caused by most governments. They do this by growing the money supply at a careful rate to maintain a small but steady inflation rate. This encourages people to spend or invest money instead of sitting on it; something which grows the economy.",
"Inflation is considered a good thing if kept in adesired range of 2% or a bit lower. This promotes healthy economic growth. The economy is based on suppy and demand. The balance of prices, jobs, wages, and production are all dependant on a steady modest growth."
],
"score": [
10,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzncbz
|
How did recording music change with the Beatles?
|
For example, what were some things that were new then that we take for granted now?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjoupn6"
],
"text": [
"Quality for them was a very important thing, that's one of the reason they abandoned tours and dedicated to studio recordings. Back then wasn't possible to have a good sound system in areas with huge crowds, if you see the videos you'll hear mostly screams of their fans. In studios they used the top equipments they had on time and had some practices like putting the microphones closer to the instruments, which wasn't a real thing before them. Some techniques of audio editing started with them as well, such double track vocals."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kznexa
|
Who is Navalny and why is he arrested?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjp193h",
"gjp2w6w",
"gjozwz4"
],
"text": [
"Navalny is Russia's most prominent oppositional leader. He's known for exposing various corruption schemes within Russia's governing elite as well as for actively criticising and opposing Putin's regime. Without going into much detail: after surviving a poisoning attempt by the FSB in August, he has temporarily relocated to Germany and Russian authorities threatened to jail him if he doesn't return, citing several court cases against him (which are totally fabricated). Yesterday he flew back to Moscow and was subsequently arrested. Navalny himself stated that he's not afraid and is prepared to prove his innocence.",
"> Who is Navalny? Alexei/Alexey Navalny is a Russian politician,. He was the leader of the Russia of the Future political party (formerly known as the Progress Party) from 2014-2018. He also ran for President against incumbent Vladimir Putin. > Why [was] he arrested? This is a more thorny question to answer, owing to its political nature, what with Navalny not being very popular with Putin and his government. Back in 2014, Alexei and his brother Oleg were convicted of embezzlement and money laundering of about half a million US dollars (or the equivalent thereof in local currencies). Initially, both brothers were jailed for three and a half years, but Alexei's sentence was later suspended (best as I can tell, the closest application in US law is being put on probation or house arrest). Fast forward to September 2020, when Navalny was hospitalized after being poisoned with Novichok, a deadly nerve agent. He has alleged that Putin was the one who poisoned him, writing on Instagram: > Like I said, somewhere there is Putin in his bunker, stomping and yelling \"Why didn't he die?\" and if he didn't die then he is twice guilty and now we will jail him. and the Trump administration blames the Russian Secret Service. CNN \"reported on the first direct evidence of the agency's involvement in the poisoning.\" with their investigation showing that \"an FSB toxins team of about six to 10 agents trailed Navalny for more than three years before he was poisoned in August with the lethal nerve agent.\" Navalny survived being poisoned and spent the next five months in a German hospital recovering. Yesterday at noon Eastern Standard Time (8PM local time), Navalny landed at a Russian airport and was shortly arrested. The official charges are related to violating the terms of his probation from the 2014 case, presumably due to him being out of the country. Kira Yarmysh, Navalny's press secretary, tweeted: > It's just fantastic. The Penitentiary Service knowing full well that Navalny is being treated in Germany is trying to jump on the last train (Alexey's probation period ends on December 30!) and demands that he reports for inspection tomorrow! Navalny rejects this explanation, stating he believes his arrest to be politically motivated. **Sources** * \"Alexei Navalny detained after landing in Moscow\" (2021, January 17). *Deutsche Welle*. URL_3 * Article 73 of the Russian Criminal Code (1996, June 13). URL_7 [English translation: URL_6 ] * Ilyushina, M. (2020, December 28). \"Russian authorities threaten to jail Navalny if he doesn't show up in Moscow by Tuesday morning.\" *CNN*. URL_2 * Ilyushina, M., Shukla, S., Dewan, A. & Hu, C. (2021, January 18). \"Alexey Navalny detained on return to Moscow five months after being poisoned\" *CNN*. URL_4 * Kaminski, M. (2012, March 3). \"The Man Vladimir Putin Fears Most.\" *Wall Street Journal*. URL_0 * \"Navalny Returns to Russia\" (2021, January 18). *Moscow Times*. URL_5 * \"Russia Navalny: Poisoned opposition leader held after flying home\" (2021, January 18). *BBC News*. URL_1 * \"Russian Supreme Court Upholds Conviction Of Navalny Brothers' In 'Yves Rocher Case'\" (2018, April 25). *Radio Free Europe*. URL_8",
"Navalny is a Russian anti-Putin activist who was recently poisoned with a lethal nerve agent, but managed to pull through and completely recover. Since then, he's been trying to trick people affiliated with the FSB (Russian CIA) to admit that Putin ordered the assassination attempt directly, with a lot of success. Basically, the Russian government is out to get him at this point because he is a threat and knows too much. When he went back to Russia, he was detained upon landing at the airport near Moscow."
],
"score": [
16,
13,
10
],
"text_urls": [
[],
[
"https://web.archive.org/web/20150102042232/http://www.wsj.com/articles/SB10001424052970203986604577257321601811092",
"https://www.bbc.com/news/world-europe-55694598",
"https://www.cnn.com/2020/12/28/europe/navalny-russia-jail-threat-intl/index.html",
"https://www.dw.com/en/alexei-navalny-detained-after-landing-in-moscow/a-56252905",
"https://edition.cnn.com/2021/01/17/europe/alexey-navalny-return-russia-germany-grm-intl/index.html",
"https://www.themoscowtimes.com/2021/01/17/navalny-returns-to-russia-a72635",
"https://www.imolin.org/doc/amlid/Russian_Federation_Criminal_Code.pdf",
"http://www.consultant.ru/document/cons_doc_LAW_10699/1fc6797cfe603f5b327aa4ea29644309db22717d/",
"https://www.rferl.org/a/russia-navalny-brothers-conviction-upheld-supreme-court-yves-rocher/29191551.html"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kznjx1
|
why do eyes get that “memory overlay” if you stare at a fixed point for a period of time?
|
What is happening there? Kinda like the red dot optical illusion, but it’s all the time, like if you close your eyes quickly you can see an image of what you were just looking at. I am terrible at explaining it, which is probably why google isn’t helping me...
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjoxvmg"
],
"text": [
"When you look at something, your eye interprets the incoming light by flipping cones and rods to create a signal for your brain to interpret. If you stare at the same point for a long time, your cones and rods (cells that respond to colors and intensity of incoming light) get tired of holding in the same position for a long time, like flexing your muscles in the same position for an extended period of time. When you look away from that point, the cones and rods need a second to relax from that long-held \"flexing\", sort of like shaking out your arms after holding that flex for a long time, before they start responding quickly again. Basically you're just making your eye cells tired and sluggish to respond."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzno13
|
Why can't you eat pills? Why do you have to swallow it? Isn't it the same thing? It's still going to get digested.
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjowads",
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"gjow266",
"gjoxg46",
"gjoxi0c"
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"text": [
"Pill are designed to break down at a specific rate releasing the medication gradually as it is digested. If you chew it up it will break down much faster and you can overdose on the medication by absorbing it too quickly. Most medications are also very bitter tasting compounds and they would just taste horrible.",
"I don't know if there's another answer but have you chewed a pill? Most taste awful 🤮",
"It changes the speed of absorption of the drug. The pill shape or casing is designed to release the drug in a controlled manner. Chewing it makes it absorb too rapidly.",
"In addition to the answers from others, depending on the ingredients, your teeth aren’t designed to handle some of the stuff contained in pills. A lot of times even the stuff that they do make chewable / gummy versions of aren’t good for your teeth (though this is usually more just because they have sugars and citric acid)",
"Like others have mentioned absorption speed is important. Another is getting the drug to where it needs to be. If you chewed an antibiotic it would just give you a fungal infection in your mouth by killing all the bacteria, whereas swallowing it would kill bacteria in other places like the urinary tract or ears. This is because the intestines are designed to transport molecules into the blood, whereas the mouth is not. The mouth does not have the anatomical or physiological structures and capabilities to transport molecules into the blood for it to take effect where it needs to. Certain medications are made to be chewed like antiemetics (anti nausea medication), because people who are vomiting generally can't swallow pills so they need something chewable."
],
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19,
18,
16,
6,
5
],
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|
[
"url"
] |
[
"url"
] |
|
kzno3n
|
how was math created and what makes it hold true?
|
Mathematics
|
explainlikeimfive
|
{
"a_id": [
"gjoxdsl",
"gjox6gg",
"gjp1gri",
"gjph62r"
],
"text": [
"I'm not a historian so someone may call me out here but I won't let that stop me: Math wasn't \"created\" and it isn't \"true\". Math is just a way to describe the world. Just like colors aren't \"created\" or \"true\". It's a specific way to describe aspects of reality that require certain language to describe. I can't describe the taste of rabbit to someone who has no common ground in flavors, so I need to find a basis that we can both relate to and tell them that it tastes \"sort of like chicken, but more the dark meat, and a bit stronger flavor\". I can't describe the tast of rabbit with colors, nor with sounds, nor numbers, nor yet feelings. Each of these are tools to address certain aspects of a shared reality. Math is a set of descriptions that encompass \"how many\" and its based on the concept of \"one\", or perhaps the difference between \"one\" and \"none\". From that common basis that all of us can relate to, we can use math's language to describe all of the things that require it. It is \"true\" only because we all seem to exist in the same reality and in this universe. In another setting we may find that our math is no longer true; that our words to describe fall short. As long as we share the same experience we can use the same language to describe it. I hope that is helpful.",
"Basically the same way it's usually taught in school. Starting with basic counting (ie how many strawberries do I have), then zero the concept of a placeholder number. Eventually negative numbers are necessary for transactions (ie you have -5 strawberries because you owe me 5) so this coincided around the invention of basic banking. Geometry came about fairly early because it could be proven with proofs rather than actual numerical calculation. Algebra was developed mostly in the middle east and was used for more complex calculations. Math comes from necessity like everything, calculus was invented when physics was studied because it was necessary.",
"The answers here are missing an important detail, which is that this is a philosophy question that has multiple possible answers with no \"real\" answer for certain. One possibility (the one that I happen to subscribe to) issue that math \"exists\" outside of human thought. That is, the concept of \"three\" exists and always has existed, and \"3\" is just a way that humans have of thinking about this idea of \"three-ness\". In this view, \"1+1=2\" is a statement that is true independent of any person ever thinking about it, and all humans did was discover it and come up with a way to write it down. Another school of thought is that math is one big game or puzzle. People have come up with a set of rules, and then used those rules to determine what else fits in that system. These rules *also* line up with lots of things we see in the world, but that's because we designed the rules that way, not because of any fundamental truth in the universe. In this view, \"1+1=2\" simply because that's how we decided \"1\", \"2\", \"+\", and \"=\" are supposed to be interpreted.",
"Math was originally created as a way to describe the world, but has left that purpose behind. You should think of math as a category of puzzles, a virtual toy-box. Unlike regular sciences that describe the world, Math is now a game all of its own, sometimes bearing a correspondence with reality, sometimes not, sometimes bearing a striking semblance but with important, tricky differences - something may work fine according to math and fail in real life because the model is inaccurate. That doesn't make the math wrong - it just makes it detached from life. You can think of it a bit like LEGO Technic. It's a mix of Lego bricks, cogs, axis, rubber bands, bendy pieces etc. You assemble them according to the rules of connecting Lego, building whatever you want. You may build something practically useful, or you can just build something pretty, impressive, behaving in a cool way, imitating some real-life example (often in a deficient way), prototyping a new real-life invention, or just trying to make a mind-bending configuration that can be infinitely twisted, or just cataloguing every single legal way you can connect three 4x1 pieces. Thing is, neither the set of bricks is finite, nor are the rules of connecting them set in stone. You can always allow a tricky way to connect them, or introduce new type of bricks or cogs that allow for a connection that was impossible/illegal for now. You can change any rules at will - you're only mandated to state every single change and violation you applied when presenting your result. And of course there will be self-imposed restrictions - voluntarily banning certain pieces and setups just to make it a more special challenge, more restricted - or at other times you introduce total cheats, bricks of stretchy jelly you can stretch, twist and connect as you desire, even plugging top of one into its own bottom. And as long as you have *some* rules, and are able to state them and keep them straight, you're valid and your math is \"true\". Not necessarily true to life but true within own framework."
],
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|
[
"url"
] |
[
"url"
] |
|
kznua6
|
Why is higher color temperature (5600k) considered cool and lower (3400k) considered warm? Previous answer explained that bluer looks like ice and yellower looks like fire which explains cool/warm, but where do the numbers come in?
|
I know in Kelvin is a temperature scale where 0 is absolute 0, but what relation to color temperature is the kelvin number?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjoxf44",
"gjphul5"
],
"text": [
"When an object is hot, it glows. Body-temperature objects glow in far-infrared light, which is how thermal cameras work. Hotter objects glow in near-infrared and even visible red light. This is why hot objects can look red. Thus the origin of \"red hot\". However, if you make things hotter still, they will glow in green and blue light as well. They then appear white, since they glow in red/green/blue all together. Hotter still, and they glow blue. However, at this point, they are usually so bright that our eyes saturate and they still appear white - the blueness is only visible through a darkening filter. This is hotter than 99.9% of the things you'll see in your life. The exact balance of blue-red depends almost exclusively on the temperature of the object. As such, we can describe this balance with a real temperature. A light meant to mimic sunlight's red-blue balance should be around 5,800k.",
"Everything emits radiation depending on its temperature (Black Body Radiation). The higher the temperature of the body, the shorter the wavelength of the emited radiation. So for \"lower\" temperatures, this means only radiation with large wavelengths is emitted. For example humans and animals emit infrared radiation that can be seen with certain cameras. If you further increase the temperature, the body starts glowing, which means that the radiation now has a wavelength that is visible. And the visible light which has the longest wavelength is red. Increasing the temperature even more shifts the color like going through a rainbow, until the wavelength is too short to be seen. However, this is not exact, so it's more of a tint than the actual color. You can see that when heating a peace of metal: it will start glowing red, then white and ultimately blueish. (Mathematically this is described by [Wien's displacement law]( URL_0 )) I also want to add something about the strange names of \"warm\" and \"cold\" light. Like you said, the color of ice and fire is a reason for this, but there are also others. Because we humans can feel infrared radiation with large wavelengths as warmth. But we don't feel ultraviolet radiation with small wavelengths. However, a body has to be a lot warmer for it to emit ultraviolet radiation than to emit infrared radiation. So a \"cooler\" body emits radiation we feel as warmth, but a \"warmer\" body emits radiation we don't feel at all."
],
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24,
3
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"text_urls": [
[],
[
"https://en.m.wikipedia.org/wiki/Wien%27s_displacement_law"
]
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|
[
"url"
] |
[
"url"
] |
kzo685
|
How can a chromecast keep playing video, without stuttering or buffering, if the device that is casting the video turned off and on while it was still connected to the chromecast
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjoyyu3",
"gjp0cbp"
],
"text": [
"All the device does is tell the chromecast what to stream. Once it does that the chromecast takes over and streams the content by itself ( until you tell it, via the device, to stream something else).",
"Think of your phone as a remote control, and the chromecast is the TV. If you take the batteries out of the remote control, it doesn't kill the TV."
],
"score": [
12,
6
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzobg0
|
Why do foods that don't taste or aren't supposed to taste like peanuts still have peanuts?
|
I always see " may contain peanuts " on stuff like cereal and I've seen a lot of episodes of how it's made so it seems quite hard to cross contaminate peanuts
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjozo1x",
"gjp0fdi",
"gjp4kps"
],
"text": [
"Many times they use that warning in plants that produce more than a single product and if just 1 if of those products had peanuts in it then all the products from there will hold that warning for liability reasons",
"Obviously not enough we’re watched while paying attention. Peanut allergy can be very severe. Just some peanut dust that was missed from cleaning, or drifting in the air, could contaminate anything else and potentially kill someone. So any facility using peanut anything in any products at the facility get that warning just in case.",
"Many processed food products on supermarket shelves are made in very large factories. In these factories, multiple products are made at the same time. You might have peanut butter cookies made next to chocolate cookies etc. It is very difficult to avoid things from cross contamination at very low levels when there are shared areas like stockrooms, packaging, shipping and receiving in a factory. For legal reasons, it makes sense for a company to provide disclaimers regarding the cross contamination possibility when their products are made in these large factories. Some people are very sensitive to peanuts."
],
"score": [
11,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzofu9
|
Why does it hurt when you quickly sniff the air inside a carbonated drink like sodas?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjp3vpd"
],
"text": [
"CO2 mixes with the water in your nose to form carbonic acid. It's like spraying dilute lemon juice into your nose."
],
"score": [
24
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzojyq
|
What exactly is a stroke?
|
Why does it only affect one side of the body? Why is there a specific “burnt toast smell” or “taste of pennies”?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjp19td"
],
"text": [
"Blood flow is required to keep your brain working. If the blood flow is stopped, or a blood vessel bursts in your brain, then parts of your brain start to die. Your brain can compensate somewhat, but there are unexpected side effects sometimes. We don't really know 100% what part of the brain does what, but we have some general ideas. So that's why all kinds of crazy things happen when someone has a stroke. Strange smells that aren't there, strange tastes that aren't there are just some of the random side effects. My mother in law completely lost her appetite and was never hungry no matter how long she went without food. There is no way to predict how a stroke will affect someone and no way to predict how much they will recover from one."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzon9x
|
how do company’s that sell a gas like oxygen/ helium collect the gas?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjp3a4p"
],
"text": [
"Helium is collected from certain natural gas wells. Radioactive elements (mostly uranium and descendents) shoot off alpha particles as part of their radioactivity. An alpha particle is just helium. Radioactive stuff in the ground eventually builds up deposits of helium, usually trapped with natural gas. We don't go out of our way to drill for helium deposits, it's just a byproduct of some natural gas production. Oxygen they use fractional distillation. Oxygen and nitrogen gas boil at different temperatures, so if you cool air you can seperate out the oxygen from the nitrogen. Cool air enough and the oxygen will be a liquid while the nitrogen still a gas. You can also get more trace gases out of the air like this too, such as argon. Just need to know the boiling points, and then cool air to the right temperature to seperate. Helium doesn't work for this though, as it's so light it floats off into space rather than building up in the atmosphere. Some gases not in the air (oxygen, nitrogen) and not underground (helium, methane) need to be chemically produced. Most obviously, carbon dioxide you just burn fuel. Hydrogen for example can be made by splitting water with electricity, or more commonly by reacting water with methane at a high temperature in the absence of oxygen (so the methane doesn't just burn)."
],
"score": [
11
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
|
kzow7c
|
What is the difference between foreclosure, pre-foreclosure and auction?
|
ELI5: I’ve been house hunting for a while now and I noticed a lot of really nice houses are listed as being foreclosure, pre-foreclosure, and for auction. I have no idea the difference between these three things or how to buy a house listed as such.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjp2zg7"
],
"text": [
"Pre-foreclosure: The homeowner is way behind on payments, the paperwork has been filed with the court to proceed with the foreclosure but it hasn't actually been processed yet. Foreclosure: The point at which the court processes the foreclosure. At that moment, the house no longer belongs to the homeowner, but to the bank Auction: The bank now tries to sell the house at an auction to try to recoup some or all of the defaulted loan amount. & #x200B; Buying a pre-foreclosure or foreclosure is the same as regularly buying a house. You make an offer, either to the bank or owner depending and it gets accepted or not. If you're buying a house at an auction, you'll need to have funds 100% available either through a fat stack of cash in your bank account or through something you can immediately draw from. You cannot buy a house at an auction, then try to apply for a mortgage."
],
"score": [
5
],
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[]
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}
|
[
"url"
] |
[
"url"
] |
kzpp2r
|
Why does our voice sound so different when hearing it from a recording?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjp6x7z",
"gjp6zf4"
],
"text": [
"Because we used to hearing a lot of what we say through sound that travels from your vocal cord through your body up to your ears, where when recorded we hear what it sounds like when only heard through air. It makes our own voices seem deeper and a bit more muffled.",
"When you're listening to your own voice the sound is coming primarily through your skull rather than the air, which tends to make it sound deeper than it actually is. Obviously when you're listening to a recording you're hearing it transmitted through the air, as other people would."
],
"score": [
11,
8
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzpy58
|
How exactly does a shepherds tone work?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjp91mx"
],
"text": [
"A *Shepard scale* works as follows: A *Shepard tone* is two sine waves separated by exactly one octave. So, for this example, let's consider middle C as 1, and the C an octave above as 8. 1, 2, 3, 4, 5, 6, 7, 8. There's the eight notes in our octave. 8, 9, 10, 11, 12, 13, 14, 15. Let's add the next octave, because it's important. (I'm ignoring the semitones -- the sharps and flats -- but the concept is still solid.) So we have middle C at 1, the next C at 8, and the C above that at 15, with the other notes equally spaced. Start off by playing a barely-audible 1 and a nice, loud 8. Next, play a slightly louder 2, and a slightly quieter 9. The two notes are the same volume in the middle (at the F^# ), and by the time the middle C reaches the next C, it's the same volume as the high C you started out with. *Now,* you start playing a quiet middle C again, and the cycle can repeat indefinitely. The reason this works is because your brain sort of \"slides\" from the rising pitch \"down\" to the note that's coming up from below, and that keeps repeating."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzqlu9
|
How were maps made before planes and satellites?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gjpgwsg",
"gjpdic8"
],
"text": [
"People surveyed lands accurately by splitting them up into triangles and using trigonometry to measure distances between points. This involves physically exploring the lands and setting up appropriate triangulation stations to do the measurements from (preferably on a high point so you have a line of sight to the other stations) and gives an accurate framework for any internal mapping. Filling in the internal details can be done using compasses, spirit levels, measuring ropes/chains and theodolites to measure all the features and such. Elevation can be calculated by measuring the gradient of the land as you go up or down it. Here in the UK we still have the early triangulation stations all over the land which were used to make fine detailed maps of the country, they are known as [trig points]( URL_0 ).",
"Explorers would literally sail along the borders in a boat and draw what they saw. That is how the first maps of America were done by Champlain. They also used compasses and star alignement to locate themselves."
],
"score": [
8,
3
],
"text_urls": [
[
"https://youtu.be/VxBlyZAl5MQ"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzqtg7
|
What is pataphysics?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjpfgg8"
],
"text": [
"It’s a silly approach to science and philosophy. The key is that nothing is assumed, ever. In other fields, we make simple assumptions based on consistent patterns, but pataphysics does not. In pataphysics, we cannot assume the sun will even rise tomorrow—what if it doesn’t? Just because something has never happened doesn’t mean it never could, so just about anything can be argued using a logical format still. It allows the scientific practitioner to play absurdist and get creative"
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzr6ze
|
How do stocks go up or down?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjpewu2"
],
"text": [
"Its actually super simple. Person A wants to sell his stock. Current price is the last time someone traded that stock, lets say $25/share. Person A puts his stock up for sale for $26/share. Someone buys it. The new stock price is now $26/share. Now, if Person A can't sell the stock, and lowers his price, to lets say $24/share, and someone buys it, that's the new stock price, $24/share. It's all just simple supply and demand. If there is more demand to buy the stock than people selling, the price will go up. If there is less demand to buy the stock than people selling, the price will go down."
],
"score": [
21
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzrm9b
|
Why is the sky not blue if we look at it from space?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gjpgwdi",
"gjpi96h"
],
"text": [
"[It totally *is* blue.]( URL_0 ) However, it you're looking *at the ground* it might be a bit difficult to spot since the ground is so much more reflective than the feint scattering of air molecules.",
"The sky is an incredibly thin layer when compared to the size of the Earth so to see the blue layer from space you really need to look at the edge of the Earth, looking at the rest of the Earth you are looking through a blue filter so it is difficult to identify that the ground or sea you see is seen through a blue filter since it is uniformly filtered."
],
"score": [
7,
3
],
"text_urls": [
[
"https://cdn.mos.cms.futurecdn.net/yRQNRdNU5fiJZ7AQBRpMkk.jpg"
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[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzrwpi
|
Why do we have different game bugs on different computers if the game code is the same?
|
Why isn't it the case that all players have exactly the same bugs? For example, if two people have two different videocards, but the game code is the same (and contains the same bugs), shouldn't they behave in the same way?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjpi9dl",
"gjpifyy"
],
"text": [
"just because the game code is the same doesnt mean it works well with the hardware and software of the system running it. graphics cards often need patches to make them run better with newer games. same goes for the code of the game, generally needs to be optimized to reduce bugs with certain hardware. not all hardware or software works in the same way.",
"While the actual game code is identical, the way that the game talks to the video cards will be different. In a way, it is a bit like traveling abroad. If you go to another country that speaks the same language as yours, but has a very different culture, you'll still have the occasional misunderstanding. LIke the word \"biscuit\". People in the UK and the US both speak English. But a biscuit in the UK is something fundamentally different than a biscuit in the US. If you are from the US and ask for a biscuit, you're going to get something you definitely did not want. But, if you travel to a country with a different language than yours that you speak and understand but are maybe not exactly fluent, you'll tend to have MORE misunderstandings and they'll tend to be worse."
],
"score": [
5,
5
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
kzrxay
|
If ants love sugar, and bees make honey, why aren’t bee hives constantly attacked by ants?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjpio71",
"gjpi0w4",
"gjpy7gh",
"gjpqf7s",
"gjpmv9o",
"gjprbay",
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"gjpzn8r",
"gjpwmlo",
"gjpx7p3",
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"text": [
"Ants are constantly trying to attack beehives. Other bees and insects will also try to attack the beehives. This is why a large number of bees is dedicated to protecting their hives from these intruders.",
"Because the bees will murder the ants. Bees are much bigger and will bite an ant in two without much trouble. And there are up to tens of thousands of bees in a big hive.",
"In some southern states beekeepers will actually put the leg stands of some raised hives in containers of water to prevent small insects that will rob a weakened hive. In theory the water will prevent small insects from reaching the stand legs and crawling up into the hive. Source: I am a beekeeper",
"As someone with Beehives I can tell you they very much do. If you have a strong hive they manage to keep the ants out. If they're weaker, or for example, you give them too much space when there are too few bees, then ants can and will steal the honey. And God forbid you drop a little bit of it in your kitchen...",
"If people like money why aren’t banks constantly robbed. It’s because very bad things will happen to you if you try. Bees are a good bit bigger than ants and will kill any ant that tries to get into the hive.",
"Ever try to take honey from a bee without a bee keeping suit? Ants don't have bee keeping suits.",
"Beekeeper here. Beehives are constantly attacked by ants, but are pretty good at defending the hive. Fun fact, there are certain microscopic mites that can destroy a hive. However, fire any colonies near the hive can control mite populations that lay eggs in the ground near the hive. So actually, ants can be good for bee populations",
"Ants do attack beehives. I had a robust hive destroyed. In spite of the bees defenses the ants were small enough to create paths and attacked the frames from the inside out. I did enjoy pouring boiling water onto the ant mound in revenge.",
"Bee hives are under constant attack, a healthy hive will have guard bees at the entrance to block invaders. A weak or dying hive will very quickly get robbed by bees from other hives, cockroaches, wax moth, and all kinds of other insects that want to eat the honey, the larva or even the wax.",
"Humans love money, banks hold a lot of money, why aren't banks constantly attacked by humans?",
"If banks were guarded by 20-foot-tall flying Navy Seals with giant spears, I bet there would be fewer bank robberies. This situation is analogous.",
"Ants don't know that there is honey in a bee hive, and they have no way of finding out. The way ants find food is that there are workers running around constantly, and as soon as they find viable food, they activate a pheromen marker and bring the food back to the colony. The marker will create a trail on the ground, and other workers will follow it to retrieve more of the food the first one found. Now if an ant happens to stumble upon a beehive entry, they get instantly massacred by the bees, so they'll never come back to the colony to create the marker trail.",
"I have endless struggles with this. Especially the smaller ants. Some are so small that the bees don't even bother to stop them. I use diatomaceous earth to make a barrier around the hive, but the rain washes it away readily.",
"Bee Keeper here, they can be a problem. The bees will keep the ant population in check, as long as it is a healthy, strong hive. Sugar ants are not typically a problem but carpenter ants can be. Carpenter ants often will set up a satellite colony between the inner cover and the outside or telescoping cover. Insecticides cant be used cause if it kills the ants it will kill the bees. Exposing the ant nest, physically removing the ants, and putting down a good dusting of chili powder and powered cinnamon seems to keep them away for the season. Unless you can find the parent colony or relocate the bee hive the problem will most likely reoccur. jmho",
"They are being attacked by ants, birds and other insects constantly. A beehive is like a nice house with a lot of money and no lock. The thing is, if you try to enter and steal anything, it's naked inhabitants will swarm you and rub their naked bodies against you until you are cooked alive.",
"They do. So do other creatures There's a reason Bees have evolved a *literal* warrior caste.",
"Ants are like zerglings and bee hives are like carriers, not hard to guess how that fights gonna turn out!",
"Random aside - *ants actually farm aphids for this reason*. Aphids feed on new plant growth and basically poop sugar, so if you see a line of ants going up a tree trunk, chances are the ants are farming the aphid poop. Since the ants are only eating the aphid's waste, there's no competition involved so it's far less of a fight compared to going after a bee hive. So now if you've ever wondered why you parked under a tree and have come back to a paint job and windshield covered in what appears to be a fine mist of maple syrup, now you know. Aphids. Source - I'm a former landscaper with a formerly sticky car.",
"They are. Constantly. Bees defend their hive and there are plenty of measures beekeepers can take to prevent them from coming in.",
"They ARE constantly in war. My father is taking care for 30 bee families, and there is always 1-2 of them that need help with the ants already inside, fighting their way up.",
"I was a Beekeeper for a few years. Honey is the secondary target. Ants really want the larva. Any hive that gets weak, sick, or low in numbers gets finished off by ants.",
"As a beekeeper, I can say that ants do and will invade a colony with the purpose of stealing honey. However, a strong colony will keep them out of the hive, or limited to the space in the upper part of the hive between the lid and frames. Some beeks will put cans of oil under the feet of their hive stand to keep ground based invasions at bay, but if the colony is strong enough to defend the hive they will do so. In the world of beekeeping ants falls very low on the list of pests to worry about, as the bees normally are able to keep them at bay themselves."
],
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10513,
9470,
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658,
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|
[
"url"
] |
[
"url"
] |
|
kzs9dv
|
What are eyelashes made out of? Do they stop growing after a certain length/age? When can eyelash falls out, does another one grow?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjpjtcc"
],
"text": [
"Eyelashes are a type of hair. It is mainly made of the protein keratin. Hairs do grow all the time from the bottom. However at regular intervals the hair stops growing and is instead pinched off at the root before a new hair grows in its place. The speed at which hair grows and the frequency at which it is pinched off varies for different parts of your body which gives the different lengths of hair."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kztcms
|
How do we process water
|
If we send water down the same way as food, doesn’t the water just get mixed up in stomach acid? If so, how do we make use of diluted stomach acid?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjpp1zo",
"gjpq18h",
"gjpp4yi"
],
"text": [
"'Selective permeability' the cells and organs can decide what goes in and what goes out of each cell. To make a bad analogy, the same way you can reach into your pocket and pull out your keys and not your wallet is the way your body directs the water to where it needs to be.",
"Stomach acid isn't as acidic as many people think, more like the strength of lemon juice than laboratory concentrated hydrochloric acid. It gets neutralized as the stomach contents pass into the duodenum, the first part of the intestines.",
"Yeah it does get mixed with acid, but right after the stomach, in the first part of the intestines, your pancreas excretes sodium bicarbonate which naturally neutralises the acid to a point where the fluids can start to be absorbed safely by your bloodstream later down in the intestines."
],
"score": [
10,
3,
3
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
kztprq
|
Why isn’t there a nasal equivalent to a yawn?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjpr66y",
"gjqzrv1"
],
"text": [
"There is - it’s called a sneeze. The yawn has nothing to do with the mouth or the jaw - it about purging air and calming your cardiovascular system.",
"Next time you have to yawn, keep your lips shut and inhale/exhale through your nose. Your jaw may still expand a bit but it’s totally possible to yawn through your nose."
],
"score": [
9,
3
],
"text_urls": [
[],
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}
|
[
"url"
] |
[
"url"
] |
|
kztqzo
|
Phil Spector
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjprmsx"
],
"text": [
"He was one of the most influential pop music producers of all time, primarily for his work in the 1960s. Is that not enough of a reason?"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzu24g
|
how exactly does blocking a number stop them from not being able to message you
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjpxmvm"
],
"text": [
"For landlines, (if those still exist in your spaces. They barely do in mine), blocking a number is accomplished at the “switchboard” end of things. Basically when a call comes in from a number to a number, the call router will check a database to see if the calling number is blocked first before forwarding the call on. This probably only happens at one “node” along the call’s journey, but not sure which one. Mobile phones and messaging services likely work similarly. When you block someone, your client app will add that number/profile to a blacklist to check against when receiving a communication. It *may* also share the blacklist with the network servers/cell system, which will stop the call when it enters the system because then bandwidth isn’t wasted on sending a call that is doomed to fail. Not sure if that happens necessarily, but it would seem the logical approach"
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzue5x
|
Why are employee or companies checks are bigger than checks we write as ordinary people?
|
I've never really understood why the employee or instruction checks are bigger. Like is there a reason why the size bigger is it for security reasons or something I don't know.
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjptxta",
"gjpuiam"
],
"text": [
"They are often printed on letter size sheets of paper probably for convenience so they can use standard size paper and printers.",
"Technically a check can even be written on a cocktail napkin. The bank might not like it, and delay processing it. Consumer checkbooks are designed to be small enough to fit in a purse or jacket pocket. Writing checks was a very common way to pay for things until credit cards became common in the mid 80s. Business check are designed to fit in either a 7 ring binder like this: URL_0 Or on large laser printers and come in various forms like premade envelopes, regular letter size paper and even on giant continuous feed sheets for dot matrix style printers."
],
"score": [
6,
6
],
"text_urls": [
[],
[
"https://www.amazon.com/dp/B01L9NGW3U/ref=cm_sw_r_cp_apa_fabc_UTybGbGHGPPEN?_encoding=UTF8&psc=1"
]
]
}
|
[
"url"
] |
[
"url"
] |
kzuxqy
|
What does it actually mean to install a software? What is the computer/OS doing that means it is installing?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjpwuw2",
"gjpzudu"
],
"text": [
"Broadly speaking it means just copying files to the locations they belong. For most Windows apps this is inside `C:\\Program Files` (or whatever it is these days), but there can be a few management steps involved as well. Putting an entry into the start menu, on the desktop (eww...), adding a file type association so that double-clicking a document/file will run your software to load it, and maybe other things like that would be appropriate. \"Installing\" software will usually accomplish these steps, and Uninstalling will delete them.",
"Funny that you ask, I'm working on creating an installer for a project right now. There are already some excellent answers here, but I'll add my own because there are some things not mentioned. An installer can first check if the program is capable of being installed on a system. Maybe your OS is too old, and then the installer will tell you that. Then, the installer can also check if any dependent programs required are installed or not, and optionally install them right away. For example, to install \"MyProgramB\" you first need to have \"MyProgramA\" installed. Then, you'll usually have to provide some kind of input in the installer. The install location, if you want the full program (complete installation) or just a couple features, maybe some additional parameters etc. Using these parameters, the installer will decide what files to copy over into your system. The installer usually registers the entry point for the program (MyProgram.exe on windows) in the start menu folder, so that when you search for MyProgram, it'll find that .exe file to start up the program. There's many, many more things that can happen during installation, for example adding entries to the registry (kind of a system wide database) or setting up a web server on your computer, but the above is the basic procedure."
],
"score": [
11,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzv06m
|
How does the map of Pangea even slightly esemble the current shapes of all the continents?
|
Is it just a visual representation? I mean It's not like a piece of land broke off and floated away?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gjpxjiw",
"gjq1xdu"
],
"text": [
"> I mean It's not like a piece of land broke off and floated away? Dude.. that IS what happened. I usually give descriptive answers to stuff I know about, but for you I'd recommend reading up more on Pangaea\\* and tectonic plates. Also, tectonic plates are not liquid (or else we'd be floating instead of standing/sitting) and since solids don't change shapes that erratically, you'd expect the shapes of most landmasses being similar atleast near the places where 2 plates didn't crash head on. Where there WAS head on crashing, you can see changed shapes and mountain ranges - like the Himalayas",
"If you look at a map of south east Africa, you'll see that there are two very large lakes, which are curiously long and thin: Lake Malawi and Lake Tanganyika. They are among the worlds top 10 biggest lakes, you can't miss them. These two lakes are also rather deep, despite their thinness, making them both top 5 lakes per volume. & #x200B; These lakes are part of the rift that is being created by the eastern part of Africa \"breaking off\" and \"floating away\" right now. In a few million years, it will be its own seperate landmass."
],
"score": [
23,
5
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
kzv2qm
|
What’s the difference between a MRI Scan, CT Scan, PET Scan, and X Ray?
|
By the way, I know what an X Ray Scan is but I don’t understand exactly how it works.
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjpyacy",
"gjpz517"
],
"text": [
"x-ray = 2D, shoots radiation to get a 2D picture of the target area. primarily just for seeing if something is fractured/broke MRI - 3D image, used to primarily see soft tissue injuries. more detailed than a CT but takes longer CT - lots of xrays stitched together to make a 3D image. Used if patient has metal inside them or in case of emergency. quicker than an MRI and doesn’t use magnets so safe for metal implants. PET scan is different: you basically get juice that has radioactive markers in it which lets doctors see overactive and under active areas of the body which may indicate cancer or an infection",
"Xray - basic picture through the body, and mainly good at seeing dense things like bones but can be used to see changes in density in lungs for chest Xrays CT Scan - Take an xray machine, make it go in a circle so you can take hundreds from different directions, then use a computer to sort out the data into a 3D model. 3D Xray! Similar to a standard Xray its mainly good at seeing differences in density MRI - MRIs use strong magnets and RF to excite the hydrogen atoms in your body, this lets it see soft tissues and anything with a high concentration of water in it. Xrays can detect differences in density, MRIs detect differences in concentration of water so Bones look different from tendons which look different from muscles and fat. PET scan - Positron Emission Topography adds a \"tracer\" chemical to your blood which has Flourine-18 in it which decays by launching a positron instead of an electron, this positron will hit the first electron and then turn into two gamma rays shooting opposite directions and the detector can then figure out where it was. Because the tracer is moving in your blood, PET scans are good for detecting areas of high/low blood flow which can show if your organs are working well or if there's a tumor commandeering more blood than that region should have. Basically there's an assortment of different tools depending on what you want to look at. An Xray is super cheap and easy these days (there are small carts that can do them) while PET scans and MRI scans require expensive dedicated equipment but can show you things an Xray never could."
],
"score": [
12,
3
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
kzvacg
|
Why, in languages with accented letters, are only some letters considered to be their own letter?
|
If you take Spanish as an example then "ñ" is viewed as a separate letter to "n" but in some words you have can have an accented "ó" so why is that not a separate letter like "ñ" is? Also apologies if I'm wrong about something in this post or getting mixed up :)
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjpysgm",
"gjq2fef",
"gjpzyuy"
],
"text": [
"They didn't have worldwide standard rules when they came up with this stuff, so there are just...inconsistencies. Some guy in Spain decided that n and ñ are different characters because they sound different, while a few hundred miles away in France, they decided that there's one letter, e, and the acute, grave and circumflex accents just modify how you pronounce it. Different approaches. Both countries have restaurants and novels and MRI machines, so it looks like both approaches can work. If we were redesigning all our languages today, we'd probably have one system for this, but at this point it's too late.",
"ETA: I see someone gave this answer while I was typing it all out, but will leave it here anyway. Taking Spanish as an example, “n” and “ñ” are different letters because they sound different. Look at H and Q in the English language, for example. Those aren’t the same letters because they make two different sounds. For example, año (AH-nyo) means year, while ano (AH-no) means anus - so, even though they look similar, they’re very different letters. They also have two different names in Spanish when you say the alphabet. On the other hand, “o” and “ó” aren’t actually different letters; the accent is there to tell you where to put stress when you pronounce the word. “Donde” and “dónde” both mean “where,” but when the stress is on the second syllable, that means that the sentence is a question. So “donde” would be used in a sentence like “that place where he he went” vs “dónde,” which would be used in the sentence “where did he go?”. I’m a language nerd, so here’s some more info that I think is interesting, but isn’t critical to answering your question: Moving past the “like I’m 5” level, the reason for all this is the evolution of language. Spanish evolved from Latin, which is why so many of the words are very similar. Taking “ñ” as an example, the Latin word for year is “annvm” while the Spanish word is “año.” At one point in history, scribes decided that the easiest way to save space when writing “annvm” would be to stack the two n’s on top of each other. Over time the top “n” shrank, and the letter became ñ. Also the reason people from Spain lisp some of their letters is because those letters originated from a glyph that no longer exists (it kind of looks like a “j” that has been rotated 180 degrees). “S” is still pronounced the same as in English, while the “c” and the “z” are the letters that are lisped (in cases where they would otherwise be pronounced as an English “s”). That’s....probably more than enough information without boring the heck out of you, though I probably already have. I took a lot of language classes, including Latin and Spanish, and love etymology and linguistics.",
"It's because a lot of languages, including Spanish, use the Latin alphabet for writing, but have to deal with extra vowels or consonants that aren't \"covered\" by the Latin alphabet. The accent symbol is just an aid for how to pronounce that word. French has accents too, used to indicate that that particular vowel should be said louder. For example frère, the first e is pronounced strongly, whereas the second e is silent (almost not pronounced at all). On the other hand, the ñ is actually a completely different sound, they just chose that symbol for it that looks like an n. As an example, German has an s and a sharp s, which they write with a completely different symbol, ẞ, as opposed to some sort of squiggle over an s. They basically borrowed a symbol from the Greek alphabet, rather than using a squiggle and a Latin alphabet s. Many languages have letters with squiggles to indicate the sh, tz, and ch sounds, again because they use the Latin alphabet for writing, but have to deal with additional vowels or consonants that aren't \"covered\" by the Latin alphabet. Other alphabets that can be used for writing are the Greek alphabet (alpha beta gamma etc.) and the Cyrillic alphabet (Russian, etc.). Because these alphabets are \"custom-fitted\" (so to speak) to their respective spoken languages, they don't have this issue, but another language trying to adopt these alphabets would have to use squiggles to denote sounds not handled by the alphabet."
],
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11,
10,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
kzvluh
|
how did the WSB GME short work and how did people earn money on it?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjq0xre",
"gjqc2it",
"gjq1i7b"
],
"text": [
"Shorting a stock basically means you are making a big bet that the price of a stock will go down. Basically, you borrow some stock, sell it right away and hope you can buy the stock at a lower price in the future when you have to return the stock to the person you borrowed it from. It's a very risky bet because if the stock's value goes up instead of down, the losses can be huge, much larger than the original amount of money. If the stock triples in value, you lose double your money. When it works, like when a stock collapses, you can make huge amounts like when people shorted stocks just before the 2008 crash.",
"It's possible to short a stock by 144% because there are multiple trades of same shares. I short 100 shares of GME stock at $25, which means I borrowed and sold shares at $25 to somebody. Now those shares get borrowed to short the stock at $26. That's 200% short interest. Now, shares jump to $35 instead of fall, and those short sellers either panic and choose to cover their short sale, or get a margin call where the lending bank requires either shares or cash to prove they're still good for the money they owe. So one panics and buys at $35 and by the other time the other acts, it's now up to $40. The panic from those who bet the stock would go down instead ends up fueling the price up even further -- you've got 2 sets of buyers driving the price up. Those who believe in the company and think it should go up, and those who bet against it and are needing to bail on that bad bet. Those who anticipate it going up on this account could have bought shares or options that benefit from the stock continuing to go up.",
"Yes it is possible although probably not all that legal, but what are laws when you're an institution right? Basically institutions are betting that gme goes bankrupt, but since Ryan cohen bought shares and is looking to reinvent the company a lot of people are seeing the potential in gamestop. This is driving the stock up, rn to 40$ a share. We hope the squeeze is gonna happen once there will be more good news and the share price rises further. This will lead to short sellers being forced to buy their shares back, which they previously sold. But because the price is so high now its gonna be stupid expensive for them and the declining availability of shares to buy will push the price quickly and highly. So yes, buy gme (serious)"
],
"score": [
61,
32,
15
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzvvuj
|
Why do mammals need sleep,if in nature this makes them vulnerable and easy prey?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjq3oj0"
],
"text": [
"at the end of the day, we don't know. But prey animals sleep less, gazelles only sleep for about an hour (in 5 minute bursts) while lions sleep 15-20 hours a day. That being said, there is stuff that goes on during sleep. Growth hormones are released to help repair small bits of damage your body accumulate throughout the day. It also appears to have something to do with memory, possibly sorting through short term memory and moving important stuff over to long term (this is why dreams are so hard to remember)."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzvxfa
|
Why are bitter foods and drinks often "acquired tastes"
|
Thinking things like coffee, beer, grapefruit, dark chocolate, olives, and vegetables such as brussel sprouts, cabbage, and kale?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjq3elp"
],
"text": [
"Because bitter is usually an indication that a fruit is not ripe, or possibly poisonous. So the brain learns with repeated usage that although \"bitter\" is usually \"poisonous\", the specific taste of beer or coffee is acceptable. You're not learning to love all things bitter, just the specific tastes of coffee, beer, olives, etc."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzw7f8
|
How are sunset and sunrise times calculated in hilly or mountainous areas?
|
Sunrise and sunset times seem to be pretty accurately estimated at sea level. However, when the horizon line is a mountain or hill, the times are wildly off. Why is this? Obviously, much of the landmass on earth is not at sea level. Why haven't we figured this one out?
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gjq58t3",
"gjq66pc"
],
"text": [
"The sunset and sunrise times are still calculated in the same way. A large part of the light during daytime does not come directly from the Sun but rather from reflection in the sky and surounding hilltops. So it is still noticably darker after sunset even though the Sun have been bellow the horizon all day. It is possible to calculate the actual sunrise and sunset using topological maps of an area and the exact possition. However this is usually not as useful to people.",
"It doesn't have anything to do with sea level, it has to do with your personal horizon level. If your elevation is lower than the horizon (in a valley), times will be slightly later for sunset and earlier for sunrise. If you are higher than your horizon (atop a hill), then the opposite will occur. Because the earth's surface has so many elevation changes (and they can vary so wildly in relatively small areas) the sunrise/sunset timetables ignore these differences and treat the earth as a smooth surface. The differences between the time shown and the time you experience the sunrise/set should be mostly static though, and with some research and trigonometry you could calculate what the difference should be for your house...or you could mark what time these events happen for you, and use some subtraction and addition to figure out how much you need to adjust the timetables to figure out when sunrise/set is for your house."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
kzwxy2
|
Why is it hard to hear things temporarily when you yawn?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjqsfhj"
],
"text": [
"There's a muscle inside your ears called the tensor tympani, whose purpose is to block loud noises from reaching the inner ear, such as when you chew food. This muscle contracts during a yawn as well."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzxjn1
|
Why does anaphylactic shock happens?
|
I really want to understand that, not only how it happens but also why. Every site I reached out either gave a too complex of an explanation or one that explains next to nothing.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjqbxuj",
"gjqbzjt"
],
"text": [
"In the case of an allergic reaction, your body’s immune system treats the food you ate as something really dangerous (which it isnt supposed to) and goes into overdrive to try and get rid of it causing swelling, vomiting, and other symptoms of anaphylactic shock which can lead to death",
"The most basic way I can explain it is a massive over-reaction to a threat. So if you have something bad in your body, your body fights it off. The ensuing fight causes temperatures, swelling, etc as your body kills the threat. Anaphylaxis occurs when your body goes insanely over the top... like a footballer who pretends to be badly beaten when another player runs past him... so your body goes into overdrive... loads and loads of swelling etc as it uses everything it has to kill the 'bad guys' e.g. a peanut. This gets to a point where the fight to get rid of the bad guy does more damage than good, and the swelling stops your breathing. Often it can be a case of a throat closing because something enters through your mouth (like the peanut again) and the body targets that area. The body also does this cool thing where it remembers something from past exposure... so you can have a little or no reaction the first time you encounter something, but the second time and so on, your defense system goes \"guys, I remember this one!! Kill it with everything we have!!!\" So some people may not become allergic to something straight away, but have a bad reaction the second time they have it. Hope that helps!"
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzxl1l
|
Why does french baguette taste amazing fresh out of the oven but then stales within a few hours, compared with other fresh breads that can last for at least a day or two?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjr1icz"
],
"text": [
"French person here : proper baguette should not dry out / be stale in a matter of hour. They should last a full day and a half, at least. Supermarkets don't really make proper bread, so comparing their baguettes to real ones is like comparing Subway bread to any other bread... Sliced loaves of bread are pretty unnatural, as far as bread goes. They last for weeks, do not dry out but end up molding. Usually, thats because of the additives put in it to extend their shelf life, but it's also because of their density. Baguettes have a lot of air in them, that make the inside all fluffy when it's fresh. That air makes it dry out faster than sliced bread. The world of bread is a vast one, and a lot of things will impact how and when a bread dries out or go stale. The type of yeast used, the mix of flower and their coarseness, additives to the flower (nuts, grains, oils....), how long the dough is kneaded, how long it rests, the way to cook it (pottery oven, wood oven, industrial oven, steamed). My parents local baker was crowned best baker in France a few years ago (meilleur artisan de France). He specialises in older forms of bread. My parents can buy a loaf (the round kind, not the sliced square kind) from him and keep it on the counter in a folded tea towel for a full week and it will still taste as nice as the day it was bought."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzz1l1
|
Why do broken LED lights flicker?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjqk3tb"
],
"text": [
"They always flicker, just normally so fast you can’t see it. Failing LEDs may slow enough that you notice it. Either some of the diodes are going, or some of the circuitry controlling the distribution of power within the light or fixture is fading."
],
"score": [
4
],
"text_urls": [
[]
]
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|
[
"url"
] |
[
"url"
] |
|
kzz5w3
|
When you empty the recycle bin on a PC, where does all that data go?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjqlurc",
"gjqmnhc",
"gjqqp4u",
"gjxr7tf",
"gjrnq88"
],
"text": [
"It's basically like a hidden folder, when you empty it the location as to \"where that data lives\" on the disk is deleted. This is know as the FAT table (file allocation table). The data is still there, but the OS no longer knows where to find it, that space will eventually be overwritten.",
"Nowhere. The computer just forgets where it is. On a traditional hard disk drive, rhe data won't really be gone until the computer saves new data in the same spot, which overwrites the deleted file data. Newer solid state drives don't hold onto old data like that, which helps them run faster, but also makes it much harder to recover things deleted by mistake.",
"The joke answer: The computer landfill. Real answer, think of your hard drive as a book. There is a table of contents that's says where each file is on the disk. When you delete it from the recycle bin the entry in the table of contents is removed. The data is actually still there on the disk, but the computer no long has an entry to find it. Eventually that space on the disk will get recycled and reused.",
"first how is data stored? Well, it works like this: first there is a special information on the hard drive that says \"this is this file, it starts here, and ends here\" and then on the hard drive is that information when you have a file, and want to access it, your PC searches for for that special information, reads where the file is, and then goes there and reads it. when you want to save a file on your PC, the system checks these special informations to see with spaces are not occupied by anything. then goes there and even if there is somewhere there, it just writes over it and writes the special information thingy saying where it is. when it saves something, it only cares about that special information thing. if it's not there, then it doesn't know the file exists. & #x200B; when you put something in the recycle bin in pc, nothing really happens to anything, it is just a note that says you dont want this file, but the system wills till prevent it from being overwriten and everything, and you can retrieve it any time you want fully intact. and also you dont free-up space by moving things to recycle bin. & #x200B; when you empty the recycle bin, the system removes the special information thing for all the files that were in the recycle bin. it doesn't remove the information from the hard drive, because there is no need too. the system no longer knows these information is still on the hard drive. but you DO free up space by doing so, because if you now save some new data, it will just save it on top of the old files, overwriting them, like they are not even there. & #x200B; That means it is possible to recover these files - this is why older (very old) Windows versions had a program called \"undelete\" with would search for files without that \"special information\" on the hard drive. If they were partially overwritten, they would be corrupted (so for example after overwriting a deleted image, and recovering it, you may only get half of it back) Now Windows doesn't have this function, but there are specific programs that do the same thing. Search for deleted files on the hard drive. & #x200B; *That pretty much answers your question, but below is some interesting information if you are curious* & #x200B; If you have confidential information on the hard drive, there are programs that will go to this place and replace all the bits with 0's so it can't be recovered that eazily. This will however take MUCH more time, than just deleting the special information thing that says where the file is. However, it is still possible to recover this information, by removing the disc from the hard drive and examining it with special devices, because there will still be little magnetic energy on the surface on the hard drive, that can be retrieved (files are stored as bits, which are 1 and 0's, and magnetized part = 1, not magnetized part = 0) so even after deleting, and using programs to completely delete this information, if police gets search warrant to investigate your PC they might be able to recover it. this is NOT something averge computer user should have to worry about. For peoples still concerned, there are programs that will repeatedly overwrite the information with randomly generated data, or special algorithms, so it's basically impossible to recover by anyone. & #x200B; & #x200B; PS. I weirdly feel good explaining stuff like that so i hope you understood :) ask if you want me to explain something better",
"Imagine you have a bunch of coins that are painted so one side is white and the other side is black. You can lay the coins out in a rectangular grid and arrange them to form a simple black-and-white picture. After making the picture, you flip all the black coins over, so they all have the white side up. Where did the picture go? The picture was not just the coins, but the specific pattern of coins. When the pattern changes, the picture doesn't go anywhere, it simply ceases to exist. Data on a computer is like that. It's effectively lots of little on-off switches, but the data is in the pattern of which ones are on and which ones are off. As others have mentioned, most of the time when you tell a computer to delete a file, it doesn't actually turn all the switches off. That's because doing so takes a long time. Instead it just marks those switches as available so the next time you save a file, they can be used for the new file."
],
"score": [
24,
11,
6,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzz8vu
|
what’s the window of opportunity to save someone from a brain aneurysm?
|
It doesn’t seem immediate, but isn’t it still very fast? Dr Dre just survived one but I remember Grant Imahara didn’t
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjr0s1p"
],
"text": [
"I don't know the specifics on Dr. Dre's aneurysm but in general an aneurysm isn't life threatening until it bursts or starts leaking. At that point a lot depends on the severity of the bleed and how quickly the patient gets proper medical treatment. My uncle had a ruptured aneurysm in his brain (this was a couple decades ago) and from what I've been told it was relatively minor. He has zero lingering symptoms after healing from the surgery to repair it. A family friend had one a couple years ago and despite being on the grounds of what is apparently one of the best facilities for this in the western US when it struck (she was a medical sales rep and was just finishing up a sales call). She was effectively dead within minutes of the onset of symptoms (she was on life support for about a week but the prognosis from the get go was that she would almost certainly never recover).."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
kzzeif
|
What is ACID compliance in the database?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjqmx11"
],
"text": [
"ACID stands for: - Atomicity: it can manage a set of operations as a single \"unit\", so either everything succeeds or everything is aborted and comes back to the previous state - Consistency: basically, things are only saved if they respect all kinds of requirements defined by the database administrator - Isolation: you can have 10 people working on the same database simultaneously and the resulting state is exactly the one you expect if those 10 people worked on the database one by one - Durability.Things are actually saved in a non-volatile memory (so not just in RAM)."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzzk1f
|
Why to chubbier people tend to breath much louder than someone who is in shape?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjqofvo",
"gjqqbrk"
],
"text": [
"It takes more effort to expand the airways with more weight on you. There are also a few airways that constrict slightly as you gain weight, which is a cause of snoring as well.",
"Heavy breathing is often more about poor oxygen intake (ie, the body has to work harder to keep proper blood oxygen levels) and this makes the whole engine run harder. Your observation of this being correlated to heavy people is partly accurate, but it may not be related to their size. I know plenty of chubby people who breathe well and others who don't."
],
"score": [
11,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzzsl0
|
Why does burned / charred food give you cancer?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjrd2fw"
],
"text": [
"There's a couple reasons, but they come down to the fact that when food burns, it's a chemical reaction that produces new molecules that act differently than the food molecules they came from. Some of them make good tastes and smells, but some of them can harm your DNA. Some of the new molecules that get made when food burns are kinda flat and pancake-shaped. Some of these flat pancake-shaped molecules are just the right size to fit between your DNA bases. When a cell divides it has to make a new copy of its DNA (so both cells can have a copy), and if the gizmos copying the DNA find one of these pancake molecules jammed in there, they don't know what to do and just kind of wing it when making the new copy. This introduces mutations into the new cell's DNA. **Most of these mutations are harmless.** Our genetic code has a *lot* of redundancy built in for these sorts of things, but if one happens in the wrong place in the wrong gene, it can turn a healthy cell into a cancerous cell."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
kzzvrk
|
How do companies not turn a profit for years yet not go under?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjqpbah",
"gjqoz02",
"gjqq03b"
],
"text": [
"1. **Burning venture capital** - This is what Uber is doing. Torching massive piles of VC money in an attempt to corner the market before jacking up prices and trying to actually become profitable. 2. **Reinvesting in the company** - Amazon spent a lot of time doing this. Taking every extra dollar and throwing it right back into the company. The earnings were plenty to cover costs, but all the extra was used for company projects so there was no profit. 3. **Tax dodging!** - The official books say there is no money, but the owner has a suspiciously large yacht.",
"I could be wrong here but I know some business’ don’t necessarily want to turn a profit. Primarily you pay taxes based on profits, if you show no earnings then it decreases your end of year pay outs. As long as you’re breaking even you can still stay afloat",
"If a company is re-investing all of it's revenue back into itself, then it makes no profit. A company gets taxed based on profits, so often times it can make more sense for a company to re-invest all of it's earnings back into itself. Companies can potentially return more value to owners this way rather than paying out a profit-sharing dividend. See: Amazon which famously did this for years. Investors were fine with this since they saw much higher value returned to them through their share prices increasing."
],
"score": [
17,
7,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l00i8m
|
Why is desalination so hard, also what would be the benefits of being able to take massive amounts of ocean water and make it fresh?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjqsp3v"
],
"text": [
"It's not hard, as much as it's expensive. Boiling water is easy, we've been doing it since the dawn of human civilization. Boiling enough water to supply our needs, millions and millions of gallons, takes a ton of energy. If we could get an infinite amount of energy, there wouldn't be a problem. Well, the sheer amount of excess salt that would need to be dealt with in a safe way, as just dumping all of it into one place at once could be pretty bad for the local wildlife."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l00sb4
|
What’s the difference between an explosion and an implosion?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjqubf6",
"gjqyal8",
"gjqxpav"
],
"text": [
"An explosion is an increase in pressure that expands outward. An implosion is a decrease in pressure that sucks inward. Also describes something falling into itself. For instance, demolishing a building with explosives designed to weaken the structure so that it implodes into itself. Another example would be breaking a light bulb. It's a vacuum inside, so when it breaks, the glass imploded instead of explodes.",
"fill a plastic bag with air until it pops = explosion suck the air out of a plastic bag til it crushes in on its self = implosion",
"An explosion is a lot of pressure throwing stuff away from it, like a bomb that blasts everything around directly away from the centre. An implosion is basically the opposite, where instead of exploding outwards, things collapse inwards. A submarine that gets very deep in the ocean may get to a point where the pressure outside is too strong and the pressure inside is too low in comparison, and it implodes, basically being crushed like a can. You can simulate this yourself by getting a small plastic drink bottle and sucking out all the air until it implodes from the pressure."
],
"score": [
13,
3,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l01bc1
|
Why do humans live much longer than many animals?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjqyvyq"
],
"text": [
"1. Modern food security, medicine, etc. has helped us to routinely live far beyond the average lifespan of 50,000 years ago. Wild animals are constantly fighting disease, starvation and predation by things that want to eat them. That said, this is mostly a change in *average* lifespan. The max age we get to before dying of old age has been in the 70s-80s since at least we'll before civilization. 2. Larger animals tend to live longer than smaller ones, in general. Humans are very large animals, in the grand scheme of things. We also develop slower than animals of similar size - we take much longer to not need constant parental care, longer to become sexual adults... more investment in each individual is associated with a longer lifespan, or that investment wouldn't be worth it. Humans also have monopause, which is rare: we can easily live beyond our reproductive years (less true for men but still). Most animals reproduce up until they die of old age. What's the benefit to living after you can't reproduce? The best answer is that we're the most social animals on the planet, and family members with decades of experience are incredibly valuable to support their adult offspring and take care of grandchildren, etc. It's reasonable to propose that without this role for older members in families or communities, people wouldn't naturally live beyond ~50-60."
],
"score": [
10
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l01tqi
|
What is the role of Pacific razor clam in nature?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjr1hfy"
],
"text": [
"Not all creatures play a positive role in nature. The creatures just evolve to their environment for their own benefit and does not necisarily evolve to fill a specific role. However the Pacific razor clam and other clams for that matter will consume smaller plancton and reducing their numbers while themselves falling pray to bigger animals like sea mammals and birds who would otherwise not be able to eat the plancton. Their shells also plays a vital role in the formation of the conditions of beaches and other coastal sea floor and therefore helping out creatures such as crabs and other bottom scavangers that thrive in these coniditons. They both create shelters for these creatures, forms the sand they live in and also provides vital minerals that they need."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l01yho
|
Sound can not propagate through a vacuum, but why can light?
|
My understanding is that it's because light waves have there own forces that allow them to travel without a medium. But it still doesn't make sense to me.
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjr0xwz",
"gjr1x77"
],
"text": [
"Light is a particle - specifically a photon. While the photon behaves in a somewhat unique way to other particles, it is still a particle, which allows it to move through a vacuum Sound doesn't have a particle - sound is the movement of existing particles. Without particles - like in a vacuum - sound cannot travel.",
"Sound needs a medium to propagate through. There was once a theory of such a medium helping light propagate as well, called ether. However after closer examination of how light propagates, mainly that it travels at a fixed speed, it was determined that no such medium can exist. Sound and light are just fundamentally different types of energy that is pretty hard to compare to each other."
],
"score": [
19,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l01yle
|
Why are wasps/hornets so aggressive, especially towards bees?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjr1822",
"gjr1dl8"
],
"text": [
"A lot of wasp species are omnivorous and hunt other insects and forage carcasses to feed to their larvae. If you’re much stronger than a honeybee and clad in heavy armor that a honeybee can’t bite or sting through, then raiding honeybee hives for their honey and larvae is a good strategy.",
"Being aggressive is a evolutionary advantage for them. Aggression helps protect their nests and the longevity of the species. Humans are hyper aggressive and thus why we dominate the planet, aggression just freaking works. Wasps hunt other insects including bees. Bees are a great source of food and wasps can be successful in taking down colonies. Wasps get a bad rap thou, they are great for helping in gardening because they do kill other animals that will eat your crops."
],
"score": [
7,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l03a10
|
when a new company trademarks a logo, how does the trademark office know it’s a unique logo without manually reviewing millions of other logos?
|
Bonus points - how did they do this before they had computers to help?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjrabu5",
"gjsspub",
"gjsqc81",
"gjtbraa"
],
"text": [
"Trademarks are only valid for the line of business it is actually for. For example using five rings to promote your sporting event is a big no-no because it resembled the olypmic rings. However using five rings to promote your line of sports drinks is fine, assuming nobody have registered a similar trademark to promote their line of sports drinks. This means that the patent office does not have to look through all logos to find similar ones but can limit themselves to one section. In addition any logos that is submited for trademarking requires a text description. This can be used to look up an index over already trademarked logos. In addition a granted trademark may be appealed if it can be shown to have been erroniously issued. So even if the patent office misses the similarities between two trademarked logos this may be resolved once these similarities are discovered later on.",
"The trademark examiner has access to specialized software that can match word marks and design marks to the trademark database. For example, you can search design marks with [special codes]( URL_0 ), text descriptions, or image-matching software somewhat like Google reverse image search. Before they had computers to help, they used the design codes to manually find similar marks in the trademark database. IANAL.",
"Trademarks are only valid while they’re being used in commerce. Most trademarks have fallen into disuse (or “abandonment”). And most trademarks are not registered with the USPTO. So those who work in trademark registration don’t have to search very long to see all the possible infringers in a particular category. And once a mark is accepted for registration, it gets “published” in a specific place where all the competitors can see it. They can challenge the registration before it becomes official, saying it infringes on their existing registered mark. The trademark office does a little work, and the private lawyers do the rest.",
"They don't. This type of thing only comes up when somebody (like the company that already has a logo just like that) complains about it, at that point they have two claims to a design and will solve it appropriately. Same goes for patents, there are over a hundred patents by different people and companies for the basic incandescent light bulb for example. Of course none of them are actually useful as they'd have to challenge the oldest patent on the record and they'd lose in court. Still, sometimes this is used as a tactic for patent trolling."
],
"score": [
200,
4,
4,
3
],
"text_urls": [
[],
[
"https://www.uspto.gov/trademarks/search/design-search-codes"
],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l03l3x
|
What purpose do T-rex arms serve?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjrb53n"
],
"text": [
"We can only speculate. Given the claws it does appear to help cutting open skin and flesh. It might give them more power and deeper cuts then their teeth would. It would also be an addiitional vector of attack so that any pray would have to not only fend off the head but also the two arms. But there are also some evidence from the way T-rex developed over time that it prefered long walks over short sprints which would suggest that it may be more of a scavanger rather then a preditor. If this is right that the arms may have helped slash open the pray to get to the good parts that were still remaining before the predators or other scavangers came and chased it off. We do see this with scavengers today where they will often be built to be able to get to the jucy organs like the liver or heart first and ignoring most of the meat."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l042yi
|
What is surface tension and how does it work?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjrduse",
"gjre7cd"
],
"text": [
"Liquids are liquids because the molecules in the liquid stick to one another. They're not attached strongly enough to avoid sliding around, but they're attached enough that they don't move independently of one another. Inside the liquid, each molecule is pulled equally in all directions by this force, at least on average, because there are always particles above/below/left/right/etc of them. But at the surface, there are no particles above them (or the much sparser particles of a gas). This means that molecules at the surface tend to get pulled back into the bulk of the liquid, because there's a net \"downward\" force on a particle at the edge of the liquid. Put another way, the liquid wants to have \"as little surface area\" as possible, because every particle on the surface is trying to get back to *not* being on the surface. Now, suppose you're a little water strider. You put your leg on the water. It *could* compress the water and displace it into a \"hole\" the shape of your leg, but in order to do so, it creates a lot more surface area, because rough surfaces have more surface area than smooth ones. Because the water \"wants\" to have a smooth surface (that is, the lowest possible energy state for it to be in is a smooth surface), displacing the water takes force - and the necessary force is more than the weight of a water strider. So the surface stays smooth and the strider can walk.",
"Many liquids have molecules that are a little big \"lop-sided\", which can cause them to weakly attract other molecules around them. Normally this all balances out (all the molecules are pulling on each other) but, at the surface, you've only got other molecules on one side. This can cause the forces to be unbalanced depending on what's on the other side of the surface. All this combines to mean that there's energy associated with the surface and the fluid will attempt to minimize the energy. For water in air, the minimum energy is to minimize the surface, so it tries to pull the droplet into a ball. For water on glass, the water/glass interface has a little less energy than water/air so the surface tension \"climbs up\" the glass a little bit, you can see this in your drinking glass. Similarly, if you fill the glass \\*really\\* full it can bulge up a little bit above the glass rim, held back by the surface tension because it doesn't want to create any more water/air surface that it has to. Basically, it makes fluids behave like they're wrapped in a very thin stretchy \"skin\" that you can break if you push it but will tend to pull the surface together."
],
"score": [
7,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l04bs6
|
Why is Accelerated Mobile Pages (AMP) bad for internet content creators?
|
Also, how to circumnavigate this problem?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjrgpc8"
],
"text": [
"When you directly access the webpage of your favorite content creator, that webpage is provided by a server of their choice which gives them creative control over your visit. During that visit, they can make money by selling ad space on their website, or by selling tracking data such as the number of visitors per day, etc. An AMP link is a website hosted by Google, which copies the webpage you actually wanted to view. Part of the copy process robs the original website of any profitable user data, and instead gives it all to Google. So an AMP link is like Google taking your favorite content creator's lunch money."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l04fpr
|
What determines whether you will have a fight, flight freeze or fawn response in any given stressful situation?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjryl9q",
"gjro4sv",
"gjrmplj"
],
"text": [
"Depends on a few things - could be your perception of how likely you are to survive the threat alongside experience and conditioning (behaviour modelled by your family of origin, awareness of bodily sensations, previous trauma etc). Check out The Body Keeps the Score by Bessel van der Kolk and Stephen Porges work on polyvagal theory for excellent insight into threat responses.",
"Can't do an ELI5 on this because everyone in each school of thought thinks they know the mechanism and knows that they are all right. From neuro biology, epigenetics, learned conditioning, personal predictive models... The list of different schools that have mechanisms for determining this goes on and on. Going into game theory shows times when going into fight is the only way to tat back in tit for tat strategy optimization but the goal of the fight is to compel equality, not to fight just to win or be aggressive... It is trying to get co operation usually as and end result. The scenarios could go on for hours. If you really want to know about this watch Stanford's Prof. Robert Sapolsky biology courses free online. He wrote the book on fight or flight",
"Goodness, I don't know how this works, but it sounds very interesting. Would it be insensitive to ask how you know you have a freeze reaction? Was there a specific event that happened to you where you learned about this?"
],
"score": [
9,
4,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l04hnf
|
What is the difference between sympathy and empathy?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjrganx",
"gjrfv0c",
"gjrhvcr"
],
"text": [
"Ex. Friends dog died Sympathy: try to comfort them seeing they’re visibly upset, and apologize for their loss, understanding they’re in pain. Empathy: relating their pain with an experience as your own. Understanding the type of pain they are going through and relating it to your own emotions such as losing a dog yourself - to put yourself in their shoes.",
"Sympathy is when you feel sorry for someone Empathy is when u can relate and almost feel their pain",
"Since it has been answered ill add, if you are being empathetic to someone, don't make it about you and keep yapping about your experience."
],
"score": [
12,
6,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l04kb5
|
What's the overall purpose of social media spam accounts? Every day on FB/IG, there are at least two fake accounts that send me requests. I have had actual people send me DMs, but they don't ask for money or try to get my info. Once, I talked to a spam person for almost six months. Why?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gjsbmp0"
],
"text": [
"They're accruing followers so they can then flip/sell the account to a business who wants a pre-baked follower list to advertise to."
],
"score": [
5
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l04s9f
|
How do ashes make your hands feel soapy when using them for hand washing?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjrjmgv",
"gjrka6q"
],
"text": [
"Soap used to be made from ashes and fat. A chemical in the ashes, called lye, is mixing with oil on your skin (and some fat in your skin) to make a tiny bit of soap.",
"Because it literally turns your hands into soap. The reaction is from metallic hydroxides in the ash and fat/oils on your hands. These combine to form soap. It isn’t going to be enough to hurt you if you only do it a few times per day but any more and it will cause chemical burning."
],
"score": [
9,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l04t6n
|
Why does light bend when it goes from one medium to another?
|
I learned in school that the light bends because it changes velocity when it goes from one medium to another, but why would that result in changing the direction?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjrlivy",
"gjsquq0",
"gjrk7k9"
],
"text": [
"Think of a row of 10 people, marching side by side. Now imagine that row of people hits a swampy area head-on. They all slow down as they hit the mud. Now imagine them approaching the swampy area at an angle instead. The marcher at one end hits the mud first, and slows down. The other marchers continue at normal speed, until the second marcher hits the mud and slows down. But the rest continue at normal speed until the 3rd hits the mud, and so on. This causes their path to 'bend' as they, one by one, hit the mud and slow down. Same thing, other way around when they get out of the mud onto firm ground- one end marcher does it first, then the next, then the next. When light moves from one medium to another, and the mediums are different densities, the light bends, just like that row of marchers.",
"I never really liked the explanation that the part outside the medium is “pushing too fast” and turning it, and I don’t think it’s particularly accurate either. So to start, this might not be ELI5, but that’s mostly just how optics goes - I didn’t really understand this until graduate school. In classical optics, refraction (light bending at a change in medium) is caused by the electromagnetic boundary conditions. Light is electric fields and magnetic fields in a coupled oscillation at a right angle to each other. The directions of the light direction, electric field, and magnetic fields are all at right angles to each other in a particular pattern, e.g. z direction light, x direction electric field, and y direction magnetic field. Using this, if the medium is the x-y plane, the electric and magnetic fields are parallel to the boundary while the light goes straight through. If the medium is in the y-z plane, the electric field is normal to (sticking out of, essentially) the medium while the light is going parallel to the boundary. Angles of the medium in between would give a combination of both scenarios. Classical E & M says when an electric field crosses a boundary, the part of the electric field tangent to the boundary must not change as it passes through, and the part of the field normal to the boundary can change if it moves some electrons around on the surface in the right configuration. The opposite is true of magnetic fields with some minor subtleties that aren’t worth talking about right now. The speed of the light actually fixes the ratio of the electric field magnitude to the magnetic field magnitude (the ratio is called the wave impedance, the same thing as a circuit resistance in fact), and the opposite boundary conditions mean if we fix one the other will reciprocate - and the two are at right angles, so the angles will work out the same too. So, the part of the electric field parallel to the surface and the part normal to the surface respond differently when they cross into the new medium - the wave moves slower in the medium, so it will want to change to adjust for that. But because of the boundary, all of this change has to come from the part of the electric field normal to the surface. Snell’s law of refraction essentially states this - the parallel component of the electric field (proportional to ni*sin(θi)) is conserved at a boundary. this can be very hard to visualize and some resources online will probably help with that, but remember the electric field is at a right angle to the the direction of the light. So, if the light hits a surface head on, the electric field is entirely parallel to the surface, and it doesn’t change as it crosses it because it is all parallel. But if the light is angled, the electric field has a component that “goes through” the medium, which can change, and that part shrinks, which makes the total light “bend” as the other part of the electric field didn’t change. A good takeaway from this might be that it isn’t intuitive at all - E & M is just a ton of math that works out nicely.",
"The easiest way to picture this is the wave model. Yes, light behaves like both a particle and wave, but this is a case where the wave model is way more helpful. Check out this picture: [ URL_1 ]( URL_0 ) The red solid lines are the peaks of the light waves. The dotted red line is the direction of travel. As the light waves hit the medium at an angle the part of the wave that's in the new medium is going a different speed. Hopefully you can see that means it's also going to have to go at a different angle. Since the direction the light is going is one and the same thing as the direction the waves are going, if the waves in the new medium is going in a different direction, then the light must bend. This would not happen if light were purely a particle, and it doesn't happen if the waves hit straight on, which we can directly observe in practice."
],
"score": [
13,
5,
4
],
"text_urls": [
[],
[],
[
"https://www.telescope-optics.net/images/light_refraction.png",
"https://www.telescope-optics.net/images/light\\_refraction.png"
]
]
}
|
[
"url"
] |
[
"url"
] |
l04xqx
|
on Shark Tank, why is the business valuation calculated as the amount of money being asked for divided by the equity offered?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gjrimt6",
"gjrk7su",
"gjsb7em"
],
"text": [
"Because it's just simple math. If I'm asking for $100,000, and I'm selling you 10% of my company for that money, then the company is worth $1,000,000. Because 10% of $1,000,000 is $100,000. It would be like me having a car that is worth $20,000, and I want to sell you 10% of it. That 10% is worth $2,000.",
"Because that's the definition of valuation. If 10% of a company costs $X, then the company is worth $10•X.",
"Here's what I think you're missing. I believe a lot of people who go on there who aren't really business people think, \"Well, I need $200k, and I'm willing to part with 10% of my business, so I should offer $200k for 10%!\" Here's the problem: an investor (unless they're not good) is not going to pay more for something than its \"value.\" So if I buy 10% for $200k, that would mean the entire company is worth $2 million. That's why Kevin O'Leary freaks out and says that company isn't worth anything near that. We can talk about business valuation, but that's a few ELI5s. The specific math is just a shortcut. In the example, 10% for $200k means 1/10th of the company is worth $200k, so multiply by 10 and you get $2 million."
],
"score": [
16,
8,
5
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l05cm4
|
Why do people in regions less exposed to sunshine have lighter skin?
|
I get that they don't need the sun protection effect of dark skin, but what's the benefit?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjrktiz"
],
"text": [
"Humans need sunlight to manufacture most of our Vitamin D. Evolution tries to balance that out with UV protection. Too dark and you don't get enough Vitamin D and die. Too light and you get skin cancer and die. Over time, various populations in different climates trended toward whatever balance best fits that climate. If you're somewhere with very low sunshine, you want really pale skin because you're not worried about UV damage and you don't have much sunlight to make Vitamin D so you take all you can get."
],
"score": [
15
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l05fjn
|
Why cant we copy the text from an image file through notepad then paste and save as image file and not get the original image?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjrovfz"
],
"text": [
"Notepad is a text editor. When you open a file that isn't text Notepad does its best to try to display it but it doesn't always work; there are many bytes that don't code to anything as far as Notepad is concerned. When you paste/save, Notepad doesn't know how to deal with all the non-text stuff and you don't get a perfect copy. If you opened the file in a binary editor that directly reads the binary code (typically as hexadecimal, 0-9/A-F), then you can do exactly what you're describing."
],
"score": [
9
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l05v0c
|
Would health or body weight outcomes differ if you: a) Eat one slice of pie every day, year round, or b) eat 7 slices of pie on one day each week, every week, year round.
|
Would the same be true for alcohol? Is regular consumption of unhealthy food/drink better or worse than periodic bingeing, holding average consumption amount equal? Had to look up spelling of bingeing/binging. Seems they're both acceptable.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjry586",
"gjs215i",
"gjsdq4s",
"gjtey0a"
],
"text": [
"Nutrition wise: It would be different, because your body adjusts based on how much it needs to work at the time. But that said, the difference would be so small it may not even be worth paying attention to. Dental: Well, yeah, because you're exposing your teeth to the sugar 7 days a week rather than just one.",
"All other variables equal it *probably* would just about even out in the long run in terms of body weight for the pie. Alcohol would be different because it is toxic (A word I hate and is totally overused but true in this scenario). Binge-like behavior would be more dangerous than one drink per day. It's never healthy to drink to the point of blacking out.",
"As far as weight loss goes, calories in vs calories out is all you need to know. So it'd be pretty much the same. As far as everything else, binging is always bad. The nutrients you get from a binge won't be useful because they can't all be absorbed at once and your insulin level spike dramatically after that much sugar.",
"The outcome would actually differ concerning the pie thing. If you eat a lot more calories than you need, like you suggest with the 7 pieces on one day a week, your intestines do not absorb all of the calories of that food. So you might eat 7 pieces, but your body only absorbs the calories of half of them. Whereas eating a piece of pie once a day would most likely mean your body absorbs all of its calories, so if these calories are above what you need, you'd gain the weight over the suggested amount of time. A YouTuber named Jeff Nippard made a video about the science behind these 10.000 kcal a day Challenges, and he explains this principle in quite some detail, if you want to investigate further."
],
"score": [
21,
13,
3,
3
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l0615z
|
What causes the skin-crawling feeling when someone you're not used to has physical contact with you(eg. trailing their finger down your arm)?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjrr02o"
],
"text": [
"I could be wrong but it’s probably a fight-or-flight response because they touched you unexpectedly and you aren’t used to it. OP did something happen?"
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l06fgb
|
how come fast food is loaded with salt, but you don't taste the over saltiness?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gjs5ewo",
"gjrunx5",
"gjta9z9"
],
"text": [
"Fast food isn't always loaded SUPER excessively with actual table salt (sodium chloride). But a lot of fast/processed food is high in SODIUM (the only thing they actually measure on the nutrition info), but it can come from things like monosodium glutamate (aka MSG, used especially in chinese food, but also a lot of fry seasonings), sodium citrate (used in cheese dips/nachos, american \"cheese\" slices), and dozens of other sodium-based flavorings and preservatives. Normal table salt is there as well, but not typically in proportions greater than you'd use at home for the same dish. For example, a hamburger patty made at home would need roughly the same salt content to taste good to most people. Same for french fries. These are just generally really fatty and unhealthy foods no matter where you get them from, and high salt is just what's needed to make them taste good (by usual american standards.) As others have pointed out, this is often a matter of being used to it. Get used to a low sodium/salt diet, and fast food WILL be horribly salty by comparison. Conversely, if you make burgers and fries at home, and eat other processed foods, you'll get used to higher sodium/salt content and still want to ADD salt to your fast food fries.",
"Partly because it's also loaded with sugar, and partly because you're accustomed to it. Go without fast food or adding salt to food once it's served and in three months fast food will taste so salty it's almost inedible.",
"As mentioned in one other answer, fast food contains a lot of sodium, not necessarily salt. Salt is a generic term for a compound formed from a reaction of an acid and a base. Potassium chloride, often called a \"salt substitute\" is also a salt. Sodium chloride is just the most common food salt used. The reason you don't taste it in fast food (or taste as much as you would expect) is because you aren't actually tasting sodium when you detect \"saltiness\". What you are tasting is the breakdown of the sodium chloride molecules when they make contact with you tongue. Without the chloride part of the molecule, you don't get the reaction and hence no \"salty\" flavor."
],
"score": [
21,
18,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l06l01
|
Why do some sounds, like dragging your nails on a black board, make us queasy?
|
I personally can't stand hearing the noise of a felt tipped marker pressed hard on paper while writing or drawing something down, as my body feels really cold all of a sudden and I feel queasy. What is the reason behind this? Does it have an evolutinary explanation that can be explaimed like I am five?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gjrv9dp"
],
"text": [
"This is actually a **fascinating** question with an equally interesting answer. So you know how most primates live in groups, right? Well, most have a scream that pretty much means \"get the fuck out, something bad is going down\" to signal about predators or other serious danger. Obviously early humans killed most of our closest species, but our closest relative alive today has a scream that hits frequencies very similar to the chalkboard sound (and they also someone's don't like the chalkboard sound). Also, it's been shown that people have different levels of reaction to the chalkboard sound, and that it seems to be at least partly inherited (i.e. if one person in your family isn't bothered by it, you probably aren't either). The hypothesis is that humans used to have an instinctive \"get the fuck out\" scream too, but that it's no longer important and we've more or less completely lost the ability to do it. However, the instinctive reaction to go on alert (uncomfortable, hair standing up, suddenly feeling anxious) when hearing the scream is still there in some/most of us. The chalkboard screech and similar sounds just happen to be close enough to our ancestors' panic scream that they can trigger it. Does that make sense?"
],
"score": [
51
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l06u1j
|
How do advertisements and pictures get put under ice in ice rinks?
|
I was watching some figure skating thing, and under the ice was the name of the event, and various advertisements. And, no sign of hocky game markings. How do these get put there? I would think the designs too exact to have been made by dying the ice. and you certainly can't put the advertisements on top of the ice. But, under the ice seems so inconvienant! You would have to let the entire rink thaw, and possiably drain it to change the advetisements or the event name. I am mistified!
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjrvqm9",
"gjso0t1"
],
"text": [
"Typically they are painted into the base surfaces once the white has been applied. Once that and the lines are dried (sometimes the lines are fabric - maybe silk) the side boards are put up and then the ice water application begins in layers. Here is a video of a rink conversion timelapse in florida : URL_0",
"We use vinyl mesh banner material. Graphics are printed on a roll material that goes through our wide format printer. The larger logos and graphics are sometimes made as tiled sections. They are laid in place over the first layers of ice and then more water/ice is applied over them, thus encapsulating the graphics. The mesh material holds firm in the ice due to the unique texture. The graphics can be used again and rolled up and stored after melting the ice. William, Minuteman Press, Fayetteville, NC"
],
"score": [
21,
6
],
"text_urls": [
[
"https://youtu.be/GIEOHVaUoA4"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l06v04
|
Why do movies only need 24 FPS, but games need a minimum of 60 FPS to be considered good?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gjrunv3",
"gjrw4xe",
"gjrxg11",
"gjrub6k"
],
"text": [
"Also, we aren't having to interact with the movie. We can passively take in 24 fps and be happy, but when actively engaged, our eyes/brain are able to handle more (60fps is nice, but we can experience more like 240 fps in short bursts).",
"A movie just needs to have enough FPS that the individual frames appear as continuous to the eye, which is 24FPS. That's not enough for a game though: There, the player is continuously interacting with the game. This leads to a much more precise experience, so a game needs more FPS so it can deliver that.",
"24fps movies have a ton of motion blur joining one frame to the next, which makes it nearly impossible to actually see what's happening when something is moving across the screen quickly. With a game, you're often reacting to something that is moving quickly, so you need to be able to see what's going on. A lower framerate also increases the amount of delay between an input(like you or your opponent clicking the mouse), and when you see the result of that input on screen. Most monitors also don't run at a multiple of 24hz, so you get stuttering when displaying 24fps content. Movies with fast motion could look a lot better than 24fps allows, but the motion blur hides a lot of problems that would need to get fixed to make the movie look good at a higher framerate.",
"The viewing experience is totally different and I feel like we're so accustomed to movies being 24 fps we just associate it as the 'movie feel'"
],
"score": [
10,
6,
6,
4
],
"text_urls": [
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l06yn5
|
If the universe began with bang and everything expanded outwards, why is there no centre
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gjrufkg",
"gjrz2kd"
],
"text": [
"Because the universe is not expanding from a point. Instead, the entire universe is expanding everywhere. A classic analogy is an inflating balloon. Imagine the surface of a balloon as a 2D universe and you inflate it. The surface expands without a point of origin.",
"The universe is expanding/inflating. Everything outside our local galaxy cluster (where gravity overcomes the expansion) is moving away from us at a rate that’s proportional to its distance from us, as the space between us is expanding. This results in objects far enough away from us being far enough that the distance between us and them starts to grow faster than the speed of light and they redshift out of our observable universe. Hypothetically, say there was a single point where the bang happened (space gets a bit weird around the beginning of the universe, and this hypothesis is wrong, but it will illustrate the point). Unless you were right on the front edge of the universe (under this hypothesis) you would fairly soon end up in a situation where the universe has expanded enough that each direction you look the furthest extents are all red shifting away out of your observable universe. At that point the idea of a center of the universe becomes meaningless - from any reference point the apparent movement of everything in the universe is directly away from the observer."
],
"score": [
16,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
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