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ce1qwb | Why can you remember nothing about a subject, but as soon as someone reminds you about one small piece of it, the rest comes flooding back? | Neuroscientists have discovered that when someone recalls an old memory, a representation of the entire event is instantaneously reactivated in the brain that often includes the people, location, smells, music, and other trivia. Recalling old memories can have a cinematic quality. Memories often seem to play out in the mind's eye like an old Super 8 home movie or vintage Technicolor film.
In the new study, researchers were able to show how the hippocampus binds together the diverse elements from an event to form a singular and holistic memory. During memory recall, the brain recalls an old memory by piecing together various compenents via a pattern that forms a cohesive remembrance of things past. Citation :_URL_0_ | 201120dd-5ad7-41d3-a0c0-e498261072e0 |
ce1r65 | Is there anything, legally, that prohibits the immigrants in the detention centers in the US from leaving? | They were caught trying to illegally enter the USA which is covered under Title 8, Section 1325 of the U.S. Code (U.S.C.), or Section 275 of the Immigration and Nationality Act (I.N.A.). They are being held for processing right now. Due to them being a flight risk, they are held in detention until a trial date can be set. Any attempts to leave is not allowed as that would let them roam freely in the USA. | 5642e40c-5e8c-4f2c-86eb-d923a1a085e5 |
ce1ri1 | How did cursive become basically a requirement for schools? | Until the 1990s home computers weren't really widely available, so people actually wrote things out by hand in large quantities. Sure in the late 1800s and beyond you could use a typewriter to be extra official, but if you ever have the chance to actually use one you'll see why people often opted not to.
Handwriting is much faster and stresses the hand a lot less than the jerky stop-start of hand-printing.
These days it's becoming redundant with word processing software so readily available, I'll admit I haven't actually handwritten anything except my name in over a decade. I'm not sure I even could anymore. | 41b51cce-beea-4b91-bf9b-1fb805acb29a |
ce23bt | How can music streaming numbers get tempered with? | The company can change the numbers to whatever they want. There's nothing that stops them from doing it. It's their system, they control it, they can do whatever they want, there is no third-party oversight or audit.
Of course, if they juice the numbers, they also likely have to pay the licensing fees on the higher fake numbers as well though, but it may be worth it for marketing purposes.
In older days, record companies used to lie about record sales as well, though it was a bit more complicated methods of some fancy calculations and sometimes literally just buying their own records. In streaming, its easy, just say "uhh 10M views", and thats that. | cc19cf8b-f957-416d-b02d-4f5e5fb9f1a5 |
ce23zj | Why is the dish sponge yellow? | Originally, washing sponges were made out of [sea sponges](_URL_1_). In fact, sea sponges are not named after the kitchen cleaning tool, but the opposite: the kitchen tool is named after the marine animal.
Sea sponges are very simple animals that live in colonies of cells, anchored to the sea floor or a rock. They are filter feeders - they pull water through the small holes in the sides of their bodies, filter out any edible particles like plankton or bits of decayed organic matter, and release the filtered water out through the large hole in the top.
Their bodies are...well, spongy. When dried and cleaned, they have a [yellowish color](_URL_0_). That yellowish color comes from the modified collagen they build their skeletons out of.
Eventually someone started making artificial sponges (which is better for our reefs). In order to appeal to people who were used to natural sponges, they were dyed yellow to match the natural sponge color. After hundreds of years using naturally yellow sponges, that's just what we expect our sponges to look like, so they continue to be dyed yellow (if they aren't dyed some other, trendy color). You can still get natural sponges, of course. Personal opinion: don't. | bc2e6283-e206-45c2-8b22-e1ec33501e9a |
ce2537 | When we see rainbow in nature, why is it U-shaped? | It's actually circular. You're seeing sunlight refracting back towards you at a specific angle, and there's always a circle of pathways that make the correct angle.
Usually half the circle is blocked by the ground, but if you're high enough to be above the rain you can actually see the complete circle. | 9b130c00-3780-4016-9ee0-191175717c59 |
ce25ol | The criteria required for an organism to be a different species from other similar organisms and why there are many different variations in humans yet we're all the same species. | In sexual animals, all that is required is that the species must be able to make *viable* offspring. A kangaroo and a dog cannot make a baby. A horse and a zebra can, but a zorse is not viable, since it cannot make children. Thus a horse and a zebra are different species. There are very rare exceptions to this, but this is the general guidelines.
Further, there is certainly less variation among human populations than most animals. Dogs, for instance, exhibit far greater genetic variation within their populations than humans do. | 46240e17-97bf-4183-8520-bdf4ebd92196 |
ce2b3g | What are enzymes | They're a kind of protein that makes it easier for chemical reactions to happen by acting as a catalyst. They're needed because without them a number of biologically relevant chemical reactions wouldn't occur fast enough at body temperature. Digestion of food, for example, would be drastically slower. | e6ad52e4-6d27-47fa-a4b6-cbe33abdb230 |
ce2bmy | Why do airplanes always experience turbulence when passing through clouds? | They don't. They experience turbulence while going through unstable air (updrafts from changes in temperature, jet streams, drops in air pressure, etc.). Clouds typically make the air more stable | 748984a6-9102-46c5-9dc1-28a10f45d486 |
ce2ebs | What would happen if you shot a gun on a hoverboard? How would a muzzle brake change the outcome? | Newton's Third Law of Motion would happen!
> For every action, there is an equal and opposite reaction.
There is force pushing the projectile out of the barrel of the gun, so there is an equal force pushing the gun (and you holding it) backwards. If this force is stronger than the force of the hoverboard pushing you forward/up, then you would be pushed back/down; if it isn't, then you would keep moving in the direct you were moving. | 617cc956-7619-454a-a24f-968203fd26d6 |
ce2gxp | Why do things discolour when left out in the sun? | The energy from the solar radiation (usually referred to as UV spectrum) energizes and changed or breaks down the molecules that either absorb /reflect different parts of the spectrum.
Thereby changing what is reflected back at us and we sense as color.
Oh damn it’s Explain it like I’m 5.
Um, okay... It's because the sunlight gives the colors sunburn. | a5af5059-7389-4071-b3c1-2c7f6571cd25 |
ce2sgd | How do railroad crossings know to go down when a train is approaching? | My dad told me there was a current sent through the rails and when the train would get close the current would short out through the axels of the train cars causing a trigger to the signals. As a kid He would lay wire across the rail to put the crossing arms down to stop traffic as a prank. That was the 50s and probably not the case any longer. | a5c453e1-65cb-483d-a6c0-c5b33820371f |
ce2vw8 | Why is grass wet in the morning when it hasn’t rained in ages? | It's dew. When the temperature drops below the 'dewpoint' the water molecules in the air can condense on to surfaces, making them wet | 4200eb68-c65e-4170-b704-801484f25cb4 |
ce2xog | How can a single speaker, such as earphones, produce highs and lows at the same time | [This figure should help explain it.](_URL_2_)
A shows 4 waves each with different frequencies and C shows what you get when you combine those waves together. (Ignore B and D). A combination of different sound waves creates a single wave with a unique pattern. So instead of a speaker moving in and out by same amount (wave amplitude) at a steady rate (wave frequency) it does a mixture of varying amplitude and frequency to create one sound wave that sounds like what you get when you combine lots of different sounds.
Copy pasted this from last time I answered a similar question - [_URL_1_](_URL_0_) | 4c7fc8b7-643d-453a-b0f6-212ad91932e8 |
ce31i5 | What is social mobility? | Social mobility in the context you're describing is the ability of a person or group to move across socioeconomic stratas. The main question is generally whether an individual can accumulate wealth and become a social elite despite not having been born into this elite class. | 4d01bf08-2e66-4b60-95f5-ab37c88cf8be |
ce33vd | Why does Microsoft Office require 100mb updates for all of its products on a monthly basis? | **Please read this entire message**
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ce3ehq | Why can all the areas in our mouths repair itself with new skin, but our gums can not? | Our cells can only figure our their function from their surroundings and interactions.
A wound in the skin of our mouth is surrounded by other skin cells. The new cells see those surrounding cells and realizes they should function as skin.
The gums attached to your tooth are different. They expect a firm attachment to the tooth that formed when the tooth first came out. Remove that attachment either due to poor dental hygiene, rough brushing, or other factors and the separated gum-line cells don't know that they should be attached to the tooth. This is why your gums don't regenerate the attachment to your tooth. | 27504b7f-2e62-4807-92f8-432bbc65d4c3 |
ce3qik | how does a country “change currency”? If hypothetically the UK switched to dollars or Euros, how would that actually go down? | Banks just switch your balance over to the new currency at a predetermined exchange rate. For a period of time they, and by extension retailers, will accept the old currency for deposits/payment, but will only let you withdraw/refund you in the new currency.
So if you go to buy groceries and pay in Pounds, the grocery store would give you Euros/Dollars/whatever back in change. Eventually this leads to all of the old currency cycling out and being replaced by the new currency.
There's typically a cutoff point by which you *have* to exchange the old currency at a bank. Say, banks will accept both currencies for 6 months, but after six months will only accept the new currency. If you keep holding onto the old currency past that point then it becomes worthless and you lose any value that it had. | 12f69ea8-697b-46ab-b65f-6bfe7308a6e8 |
ce3spl | Why does everyone hate on Nestle | Because they use water that we think of as a public resource (it's hard to really believably own water) and then sell it to people, often ruining the water supply or at the very least profiting off of a resource that ought be the publics. To many it feels like paying someone to sell you a nice lawn and then having them come to your house, dig up your lawn and then sell it back to you in a bag. You've paid them and they've destroyed your yard and given you back some of it at a fee. | b6adf39b-aa9a-41c4-a992-ea21670a5fd4 |
ce3v0n | Why did HIV take so long from the time it jumped species (sometime in the early 1900s) and began circulating among humans to blow up into a global pandemic in the 90s? | We don't really know the first time HIV infected a human. It could have happened many times prior to the beginning of the pandemic, but it simply never spread beyond the initially infected person because of the remoteness of the location, low population density, or we didn't identify it because the HIV virus was unknown at the time, and the symptoms of AIDS could have easily been missed or confused with other tropical diseases.
The reason it turned into a pandemic when it did is because of rapidly expanding human population in the Congo (where the virus originated) and increased travel. HIV made the definitive jump to humans in the early 20th century. Brazzaville and Kinshasa (then called Léopoldville) were, at the time, rapidly expanding human settlements, but travel was still difficult. This means there were enough people to sustain the slow spread of the virus throughout Africa but had little to no contact with other continents. By the 60's and 70's, this had changed, it and increased travel meant infected persons could make their way away around the world and wind up in highly populated cities which were primed for an outbreak. The current theory is that HIV first arrived in the US via the Caribbean sometime in the early 70's. | b975916d-065f-48ef-ae81-ec3b4f503c83 |
ce4bkm | What quarks are; pertaining to the subject of particle physics, and what their purpose is, aside from building blocks to atoms? | It sounds really arsey to say, but the answer to your question is that "quarks are quarks and they have no purpose".
Quarks are fundamental particles. That means they're the very smallest, most basic building blocks of the universe. We don't know what they're made of, or even if they are made of anything/have any internal structure at all. All we can say about them is how we observe them behaving:
They come in different 'flavours': up and down quarks are the lightest and most common, strange and charm quarks are heavier and less stable, and top and bottom quarks are heaviest and least stable. There may be even heavier, more unstable ones, but we don't think so. Up, strange, and top quarks all have a charge of +2/3 and down, charm, and bottom quarks have a charge of -1/3 (with -1 being the charge of an electron).
You will never find one quark by itself, they always combine with one or two others. Two up quarks and a down combine to form a proton, and two downs & one up form a neutron. Protons and neutrons are the particles that form the nucleus of an atom.
As far as their "purpose", they don't have one. Purpose implies they were designed to do a specific job or that they have intention. All we know is how they behave. | ebdf67d3-4913-487c-9478-31e2909348d4 |
ce4hp9 | why does a broken leg essentially mean a death sentence for a horse? | Horses legs are under high tension with tight tendons from the knee down. This means that when they break they often shatter. That same tendon situation also means there fairly little blood flow down the leg which makes healing slow. That means that the horse would have to spend a long time on only 3 legs, something it is too heavy for without damaging those 3 legs, or spend that time lying down or in a rig to hold their weight both of which have a high likelihood of them developing colic which is a potentially lethal twisting of the intestines. | 606b8895-f7da-4b40-9645-a8cf15bf76ae |
ce4mct | Why does the sky turn green(ish) when heavy thunderstorms / tornadoes are imminent? | Tornadoes typically happen around very tall storm clouds, which scatter light and make the sky mostly blue, and they typically happen later in the day with the sky tinted yellow/red from the sunset.
& #x200B;
You mix the deep blue with the yellow red and you get a greenish sky | d8ebe27a-9169-4735-8529-957b29bee04c |
ce4tn9 | Why do movies shot on 35mm today look more vibrant and high resolution than 30 years ago despite film technology not drastically changing in that time? | The same is also true for audio, but the ability to capture video data has outpaced the ability to process that data and display it. In the case of video, 35mm film has a roughly 11880 x 7322 resolution in an ideal scenario. With film in excellent shape and proper processing, remasters can be done with excellent quality. | 04e58960-0b8d-4047-bc68-8fc5f7b6b314 |
ce4u7o | Why do humans take so long to reach full-size compared to other animals? | There’s no pressure to grow fast. Some of us grow faster than others but no one generally dies because they’re late bloomers. If it was the case that human children faced some kind of predation then the faster growing ones would survive to sexual maturity more frequently and the genes that caused the faster growth would end up being present in more and more individuals in subsequent generations.
Parental care offsets the need for human kids to develop faster because the kids of good parents are genetically more likely to be good parents themselves. It doesn’t matter by what mechanism children (of any species) can safely reach their adult size as long as its genetically heritable. | ab8564b5-10b6-4e80-8a77-984072aba91f |
ce4xz9 | What does the "cap space" in NBA actually mean, and how it is used and calculated? | All of the teams in the NBA (and many other pro sports leagues) agree to limit the amount they pay their players to a certain total, this is called a salary cap. This helps prevent teams with lots of money from buying up every good player while smaller market teams can't afford to compete.
Next year's salary cap is set at about $110 million which means that if you've already committed $90 million to paying players that you have already signed to contracts, you have $20 million of cap space left to finish building your team.
The NBA salary cap is what's called a "soft" cap, meaning that you can exceed it if you want to, but you will be penalized by having to pay the league a lot of extra money. | 0171b041-60cc-4ed7-ac22-771ebda3edfc |
ce51ur | Why would anyone buy a bond with a negative yield? | Lots of reasons:
1. you're buying \_your own\_ bond. Most bonds require a liquidity level in the issuer to match obligation out there, and buy buying back they can decrease the liquidity level required.
2. they may be effectively trading \_currency\_ - e.g. they currency it's issue in is going to change in value so the very small loss in bond yield is made up for in currency change (relative to some other currency).
3. They may believe they are entering a period of probably loss in portfolio value but think the most secure place for their money is in a bond that has a very predictable, but reliable loss. E.G. if you believe a market is going to tank by 15%, then finding the strategy that loses 0.5% is \_really, really good\_. | cdecad6e-43d2-4f7c-9d22-36728e40afe6 |
ce5jk3 | Why do TV video clips from the 90s and 2000s look so low quality? | Video has progressed this far......
We went from 240p to 480p then 720 and 1080
Now we are close to commercial 2k and 4k standard video format. Just that's it's currently minimum industry standard to stay at least 720 | 58d92451-d35b-4bd4-86b8-deeb193e9217 |
ce5kyy | why is it that when you massage your own scalp/body you feel no satisfaction vs. the pure satisfaction when someone else massages you? | Your brain has a LOT of things its keeping track of and doing without any thought or effort needed from the conscious mind. One of those things it keeps track of is exaxtly this. Your brain knows its you doing it.
Similarly, the part of your brain that helps you navigate obstacles in a busy room isn't entirely connected to your conscious vision. Its possible for a person to experience blindness, but still have their brain process the visual stimuli they don't experience and for them to be able to navigate an obstacle course.
And of course a source of some sort because the claim sounds fucking wild.
_URL_0_ | d877ff71-d572-4f4e-9bfd-81c147c5d5e6 |
ce5n0u | In recipes, why don’t we bake cakes and other baked goods to certain temperature, like we do with meat? For example, if I’m cooking brownies isn’t there a standard temperature at which they are done? And wouldn’t that make it easier to not over or undercook them? | Cooking meat to temp is primarily to kill off bacteria. While it does affect the result in terms of texture and taste, it doesn't change the overall structure of what you're eating. A steak is still a steak at 135° or 160° or even raw at room temp.
Baking is more of a chemical process. Just getting the center of a dough ball to some temp doesn't make it bread. Some time has to elapse for gasses to expand, gluten to bond, and stuff like that. | 0770801f-de47-4f2a-bda1-c4b504d4fb4f |
ce5oiq | why does melted cheese taste better? | It's largely about how it feels in the mouth. Once a piece of cheddar has been heated to around 150°F, the matrix of milk proteins that provide its structure begins to break down, and the cheese takes on a creamy texture that many people find appealing.
Source: popsci | ee42d683-bd40-425d-8194-f43678d854e2 |
ce5scu | Why is it when we eat spicy foods, we get a runny nose in the process? | Capsaicin, the thing that makes spicy things spicy, works by activating the receptors in your skin which detect (thermal) heat, making them think there's something hot there.
When you eat something containing capsaicin, it is dissolved in your saliva and some of it enters your nose via the back of your mouth. When this happens, the "heat" effect irritates the delicate tissues of your nose because they think something hot is damaging them. The body's response to this is to try to dilute and flush out/remove the irritating substance by producing saliva, mucus, tears, etc from the glands and tissues of the nose. | 09106d39-6cd0-4e4b-a400-14055e3d1544 |
ce5wm1 | Why does the moon appear to be larger when it's just raising than when it's high up? And why does it look more yellow during this time? | It's all about perspective. The moon appears to be bigger when it's rising, because your brain has something to compare it to (hills, skyline, mountains, horizon etc.). Without anything to compare it to, it's difficult for humans to judge the size of things.
As for the yellowness or the moon, I believe it has something do with the light as it refracts in the atmosphere at that low angle. But I'm not entirely sure on that. | 2616b4f4-9e40-4b47-b480-9996030d6b38 |
ce678t | - Why do nightmares cause you to get bad/poor sleep even though you are sleeping? | It's a stress event. It's like asking why are you tired after a road trip, but not after sitting around the house all day. Driving may not be the worst thing ever, but it's certainly more taxing than watching Netflix on your couch. | 8e18c1e9-ade5-45c4-ab6f-926d99194f4f |
ce6971 | what the tension between the USA and Iran is due to. | There are two somewhat equally correct answers.
The first reason is that the U.S overthrew irans democratically elected government, and installed a pretty ruthless dictator leading to a massive backslide for the country. To be fair to the U.S this was mostly caused by the british, but the U.S was more then happy to help. They did this because the Iranian Government attempted to nationalize the Oil companies, which would have cost certain foreign oil companies most notably BP. The British government to in order to avoid paying new nationalized prices decided to enlist help of the U.S to overthrow the Iranian government. The Iranians are still not to happy about this.
The second more geopolitical reason is that Iran is the most powerful country in the middle east that resists American interest. Iran funds groups in Yemen resisting the Saudi government. The Saudi government is one of the U.S biggest allies in the middle east. Iran funds Palestinian groups that resist Israeli expansion. Israel is the U.S other big strategic ally in the region. Iran is basically the U.S of the middle east. Not as strong, but still powerful with many strategic allies that they support. Most of these allies are in direct opposition of U.S and its allies interest. | 0d348db9-068c-48c9-b3af-d1f8e78c8be0 |
ce6c5g | How does your body know when you have chewed your food enough to swallow? | Practice. Years and years of constant practice. We use our tongues and the other senses of our mouth to "test" the texture, moisture, and consistency of food constantly as we consume it and consider whether it is to a state in which we can easily ingest it. Sure, it's not an exact science but we can pretty well know the limits of our own body to safely ingest food very quickly through a little trial and error and learning from when our parents feed us when we are young. Consider why babies are fed milk first, then soft foods, then hard food. Not only is the nutritional value of the foods we eat when we are babies important but it also "trains" us, in a sense, from birth that soft foods are more easily ingested and to remember the consistency, texture, and moisture of food in that state. | b571b759-d6f5-4412-83f9-1dd681239043 |
ce6de1 | Why does pediatric feeding therapy often involve force feeding? | This is a severely autistic child. A child with this level (presumably) of autism might not eat _at all_ without a physical intervention. At severe levels the neurologic development that you'd hope would suppress resistance to interaction in favor of consumption of getting to eat just isn't happening.
So..."no matter how dire" can literally mean "child dies". In order to work through higher levels of therapy a child must have nourishment, and must be alive. | 3b638753-027e-4cf3-9e38-655f62af2c8e |
ce6rgj | Where do cell phone towers get their power? | Towers have backup batteries, they are indeed hooked up to the grid, but in the event of a blackout they have backup power for 3-4 hours. | b3176804-b198-444b-95c8-8b6ccb2403a1 |
ce73d1 | How do some medications cause suicidal thoughts? | Hey, I'm a mental health professional but not a doctor, so I'm going to give this my best shot based on my personal knowledge and experience.
Serotonin is an incredibly important hormone in our brains (also commonly called a neuro-transmitter), which plays a significant role in energy, good sleep, motivation, and general well-being.
Here's what else: the human brain actually isn't done developing until we're about 23-26 years old. That means younger brains can potentially respond differently to medications than fully developed brains.
Now, to bring those two things together: If you're a kiddo or a young adult, and you start taking a medication that increased the amount of available serotonin in your brain, that can drastically relieve your depression. HOWEVER! If you were already dangerously close to suicidality, the sudden bump in serotonin may give you just enough motivation to actually go through with it.
In fact, even with adults, this is closely monitored. If someone who has a history of suicidality is "suddenly better" after starting a new med, it is actually often considered a potential warning sign. Imagine wanting to die, and suddenly getting enough energy to actually DO it. Younger brains are more succeptible to this risk, because they're generally more prone to impulsive actions.
If anyone else can speak to this more specifically, or would like to correct something I got wrong, I welcome that. Be well, fellow humans! | 575e9417-c5ba-4012-83ed-bb5624e75799 |
ce75qp | How do smoke detectors work? | There are two types. These are simplified explanations. The photoelectric ones shine a light through an air gap onto a photocell. If smoke is present, the light which hits the photocell changes. The change is sensed and triggers an alarm.
The ionization type contain a tiny amount of radioactive material which emits positive particles. if they encounter smoke particles, they create ions which are charged atoms. They cause a weak current to flow in a chamber. The current is sensed and triggers an alarm if it rises too high. | fbe636e8-8724-400d-b778-d0910612642f |
ce76q6 | Why is it better/easier to learn a second language at an early age? | Because leaning as a kid is built into our brain. We are setup to learn as much as possible when we are children. Especially language. And this gets less and less pronounced as we grow up. | 76385862-3b15-438e-a517-b6dfed88edea |
ce78ml | what exactly happens when you experience a heart palpitation, the brief pounding or fluttering in your chest? | Usually this is because your heart is simply put, just beating faster because you were doing something that required your heart to increase in speed to keep the blood flow through your body to keep up with whatever is happening around you. For example, short runs up your stairs, maybe picking up a heavy object that requires some extra blood flow to be needed or an emotional reaction like being scared, a surge of adrenaline, anxiety or something shocking. Nothing to be concerned about often are common and don’t mean there’s underlying heart disease just a heart being a heart. | c2815b24-ff53-4261-b8bf-1f960c115012 |
ce7bqo | Can someone explain to me how Powerline Adapters(Networking) work in terms of sending data packets over an electrical line? It confuses me that there is no data interference when the powerlines are already occupied with 110v. Thanks | The power lines have 110v but it is at a steady, relatively slow frequency. The data transmission is done just by wobbling the steady wall power frequency slightly, something within the normal margin of error for power delivery but also recognizable by the right hardware looking for it. | 9d5488a1-4184-475f-b944-b27e3b52e426 |
ce7fn2 | If water levels are rising, why don’t we have methods of mass de-salinating/purifying water to solve droughts in the US? | TLDR: it's more expensive than alternatives
Desalination technology is currently expensive to operate and produces toxic waste.
The plants are large, complex, and require a large amount of power to operate. By comparison drilling wells, cleaning existing freshwater and waste, or building aqueducts costs considerably less to build and maintain.
Desalination is therefore only practical under certain circumstances where available power and money aren't the limiting factors.
You also have to consider the environmental factors, such as where is the power coming from? Much of the US's power still comes from coal fired plants so the carbon footprint of a desalination plant could be much higher than a cleaning+pumping station connected to a fresh water lake, even if it is hundred of miles away.
As for waste, the salt removed from the water is in the form of condensed brine which has to be disposed of safely. You can't just dump it in the ocean because the ultra high salt content will kill ocean life, and similarly the brine will kill plant and animal life if it contaminates the ground.
But as technology improves, and drought conditions get worse due to climate change, desalination will become a valuable option for providing drinking water for millions. | dc2b048a-a42d-40ae-9b74-d4484dc8c5cc |
ce7h7v | why are statues of men in the Roman time period always portrayed with tiny genitals? | Because having large genitals was seen as barbaric and uncivilized, therefore the ideal male form was to have smaller, minimized genitalia. It was an aesthetic choice based on the era's preferences. | b1edfbb3-f429-4bad-8c5f-9120f685af66 |
ce7lxt | Why does boiling water soften potatoes, but hardens eggs? | The composition of potatoes and eggs are different thus resulting in the different changes when they are subjected to high temperatures [via the boiling].
Potatoes contain starches in a compact form known as granules and when they are heated they swell and absorb water. This makes the straches more soft and allows us to digest them easier.
Eggs are known as a good source of protein because they consist mostly of protein in liquid form. When these proteins are heated they undergo a process called denaturation which is the breakdown of the original structures of the proteins. The new forms of the proteins then form a solid structure. | 02c990cf-7120-45bf-8a31-fa0e584e5293 |
ce7ry1 | How do surgeons create a sterile field for surgery? | Scrub you down with disinfecting agents, then open up many packs of sterile drapes to create the “field”. Wash their hands then put on sterile gloves (generally two sets) in a specific manner so as to not ever touch the outside. Also the surgical gowns are made in a way such that you never have to touch the outside of the gown to put it on. All instruments and devices are either new or newly sterilized and never handled with anything other than a sterile glove. | 762b07a1-08ba-4eac-8d54-4eab43fb58b1 |
ce7s7t | Why are laptop and tablet batteries often split into several smaller cells instead of having only one large cell? | If you hook multiple cells together in series where you put positive to negative that increases the voltage but keeps the amperage the same. Three 1.5 volt AAA cells connected in series become a 4.5 volt battery with 1000 mAh.
Hooking them in parallel puts their amperage together but keeps the voltage the same. Three 1.5 volts AAA cells become a 1.5 volt battery with 3000 mAh.
You could make the cell bigger like a AA cell which has 2400 mAh, but smaller cells can be more stable and reliable than larger cells. If a small cell goes bad it's less catastrophic than a large cell going bad.
You also have the benefit of being able to produce lots of small cells and help them together in interesting ways. A small 12 volt battery like would go in a garage door opener is 8 button batteries like from a watch hooked end to end. A small 9-volt battery like you would put in a smoke detector is 6 AAAA batteries wired together like would be used in a Microsoft Surface pen. | 7565f5ac-8822-40ce-928c-9a997c0d3aa5 |
ce7vdl | What are Branched Chain Amino Acids (BCAAs) & if the supplement form is of any use. | They are 3 of the essential amino acids, meaning they cannot be produced by the body. Leucine, isoleucine, and valine. They are also used in certain medical treatments. As long as you eat enough protein, whether it is animal or plant based, and don’t have a disease that causes issues with them, you don’t need to supplement. Even if you’re body-building, you should be eating more protein anyway so should still not need extra. The effectiveness of supplements would depend on if the supplement actually contains what it says it does, which is a common issue with supplements, and also if you’re not deficient, you’re wasting money because our bodies do not store extra amino acids. | d83d4603-e1d9-4973-a5bc-e8a0e0713876 |
ce805b | why is using cruise control more efficient than simply maintaining the speed manually? | When you drive without cruise, you tend to speed up and slow down quite a bit, by a few kph. Every time you speed up that couple kph, you waste a small amount of gas. Then there are up and downhills, which both suck up your gas. You tend to speed in both, and on larger uphills might give way more gas than nececsary.
Cruise control can detect the speed variation much earlier and adjust correctly. | b6071187-f2af-4459-8ab9-403e7f1b3c7e |
ce82mw | Why is heat bad for batteries? | This happens due to a variety of factors and depends heavily on the cell chemistry. One prominent factor is the increased rate of side reactions at high temperatures that lead to loss of conducting ions. There’s also a contribution of accelerated degradation of the material structure if exposed to higher temperatures for extended durations of time. | f0226d35-9e91-4c2d-9c2a-98e4caff9581 |
ce84xn | a human body always pees when it has to take a dump, but not want to take a dump every time it has to pee? | The muscles used to have a bowel movement cause pressure on your bladder, causing you to release both.
You're better able to isolate the muscles of your bladder. | 2f7a176d-1f2f-4119-9d3b-640395d25e36 |
ce8823 | What happens in the body that triggers hunger? Is it a time based thing or blood sugar or something? | It's a bit of everything. There's a hormone called ghrelin that rises when fasting and then drops off after you eat. Blood sugar is part of it and represents short term reserves. There's another hormone called leptin which is related to body fat and represents longer term reserves. | ca46f5da-09fe-431e-b533-638b2c223f64 |
ce8onv | If oxygen isn't very flammable why is it needed for fires | Its not flammable, but oxidizing. A fire needs three Things: a flammable substance, a certain temperature and oxygen. Oxygen is What reacts with the flammable substance in an exothermal reaction, in the course of which heat ist released | a36e2bac-f5b0-4172-9ede-c3a5e3424c77 |
ce8y7l | Why does mint flavored stuff taste fresh? | The receptors in our mouths that sense cold are also triggered by menthol, an organic compound found in mint. So basically menthol makes you think your mouth is cold.
Similarly, spicy food triggers the same receptors the sense heat. | 387357d0-ea0c-4cf5-833a-e03a0fdf4369 |
ce9oxv | What makes a good haircut? | Go to a licensed barbershop. Not a salon or discount place. Ask for a gentlemen’s cut. Haircut should run you $30-40.
Ask for a scissor cut. Long on top, taper fade on the sides.
This is pretty much the traditional ww2 style haircut everyone has. If you want to have a more extreme fade, you can ask them to use clippers down to a 1.
I personally vary my fade length down to a 0, up to scissor length of a half inch depending on the season.
Buy some “American crew” pomade off amazon for $10. Style your hair with that and a **wide toothed** comb. You can easily find one off amazon for < 5. | 53f1afc9-fe6e-406a-b4bc-22abcd959026 |
ce9tis | If someone has a condition which obstructs their airflow/ability to breathe normally, wouldn’t this cause a steady loss of oxygen to the brain and therefore lead to progressive brain damage? | No, because blood flow (and therefore oxygen) isn’t fixed. In case of hypoxia (low oxygen level in the blood) or blood loss, there are some organs who receive more blood while others don’t; the formers are called “noble organs” (I’m Italian, it’s a direct translation, maybe they’re called something else in English) and they are the brain, heart, kidneys and liver, all vital. On the other hand muscles, digestive trait and others receive less and less oxygen, thus shutting down first. The brain is the last to go | 3ac1e748-6662-423b-9c39-34964890202e |
cea1gf | Speed cameras | I don’t know where you live, but where I live, the most lanes a speed camera will cover, is two (To my knowledge) - On motorways, they have an array of speed cameras; one camera per lane.
Also, I believe most speed cameras use number plate recognition, to identify which car is the speeding vehicle.
I’m not sure how they’re able to discriminate on two-lane roads, such as dual-carriageways, but when it comes to roads with anymore lanes, they use more than one camera. I live in the UK, so this might not apply to you though. Please let me know if this answers your question | 9034e1f4-afd4-4095-91e7-7231035d58f8 |
cea59x | What is the sensation you get from expecting a certain movement that doesn't come, for example expecting the elevator to stop and feeling like you're accelerating when it continues? | To put it simply: muscle memory and habit.
You took hundreds if not thousands elevator rides in your life, you know how it goes, even unconsciously your body adapts to it.
When something out of the ordinary breaks the rutine you are used to, that feeling you asked about happens | 9238c002-2ed6-4d2e-b60a-6f9cc9d1d11d |
ceafj0 | can women’s periods really sync up with other women? If so, how? | This absolutely happens. I was going on a school led camping trip (I was 14 at the time) with about 10 other girls. We were hiking many miles over 6 days and would not have a chance at any point to pass a store. It was the type of backpacking trip where they dropped us off in one location land picked us up in another location a hundred miles away. I was told over and over to pack something in case we ‘synced up’. However, I was confident I had nothing to worry about as I happened to be ending mine 4-5 days before the trip. Plus, this way I could fit more pepperoni sticks in my pack. Cut to day two and everyone of us is starting our periods. I was far too embarrassed to admit I didn’t bring anything or was even having a similar issue despite the group being all women. I spent the entire trip miserably ruining my pants and wearing jackets around my waste. Sneaking into streams at night to wash my undies. Absolutely horrifying experience. I am never ever without a tampon on hand now.
I am sorry I couldn’t answer your actual question as I am also curious why exactly this happens but I for some unknown reason needed to share this story. | 514cb3da-8f02-4645-9c14-bb8af93aed12 |
ceat72 | How do the grooves in records actually make sound? | When they're recorded, a needle cuts into the wax at various depths based on the amount of vibration caused by the original sound.
Then when they're played back, it works in reverse: as the needle passes through the grooves and moves up and down over the contours of the vinyl (which match the contours made by the recording in the wax) it plays sounds based on the vibration patterns.
Kiiinda like when you fill up glass bottles with varying amounts of water and blow across the top of them, they make different sounds. But instead of bottles full of water you've got grooves full of vinyl at different depths. | 563633eb-ccfd-448e-9945-c88a15d06334 |
ceaxpb | How does one word end up meaning several, completely different things? | The borrowing of a related word from another language which becomes the original word's main meaning. A good example is the English word "magazine", originally a French word meaning something like "warehouse" or "storehouse" and retaining that meaning when talking about a ship's powder magazine. Then in the late 1700's in France there appeared a new regularly published literary anthology called "Magasin des Histoires" or warehouse of stories. The format proved hugely popular both inside and outside of France and spawned many imitations, which in English became known by their French name, "magazine". | 9e595fa5-ec7c-4aec-b48e-ad648224cf26 |
ceb3ha | Why does our skin prickle when we start to sweat? | Judging from the other comments, this must be far from a universal thing, but I know what you're talking about, OP. I have psoriasis, and I frequently get a terrible feeling of itchiness when I am in humid conditions and sweaty. I also get it after taking a shower. Why? No idea. My cause may be different from your cause, as I noted, I think mine is related to psoriasis somehow. | 05e598b0-f74e-4ebf-b15e-6e519092a25c |
cebduz | Keynes-ian economics | Well, Keynes' was a very prolific economist and wrote about a lot of stuff that could be considered to be part of "Keynesian Economics."
The thing most people tend to think about though was turning mainstream economic though away from ideas about a minimalist state with no role to play in economic crises to those about the state being a major actor in the economy.
We take it for granted today, where around a third of GDP is achieved through the public sector, but the idea that the state could, and should, have a major role in the economy was very new and very revolutionary.
The single particular idea Keynes is probably most famous for is the idea that cyclical trends in output from the private sector should be balanced out by the public sector. If output falls in the private sector, the public sector should spend more to prop up the economy and get things moving again.
Output in the economy has lots of feedback loops. If people spend more, businesses have more money to hire more people and pay them more, who then have more money to spend, etc. In a recession it's basically the opposite. The state, by spending money, can reverse that recessionary process. | 570ab05a-c302-46a7-ba9f-18f45f2ce3bc |
cebfx2 | what is the main differences between air-to-air and air-to-surface missiles? | There are a lot of differences, and a lot of similarities based on the missiles in question. The one largely Universal difference is in Explosive Yield.
Air to air missiles tend to pack less explosives, because aircraft take less force to destroy than a reinforced bunker, and the missile may have to pull hard Gs so too much weight is a bad thing. They are also ridiculously fast, pulling up to and exceeding mach 5.
ATGMs tend to have higher explosive mass and specialist warheads to destroy hard ground targets like tanks, bunkers and large structures, they also do not have to pull hard Gs to get on target and so can be larger, heavier and carry more momentum. They also tend to be much slower, after all the target isn’t going anywhere. | 8666305d-6f40-498e-aa54-403c531ab401 |
cebnk8 | - What does Mastering and Mixing audio actually doing? | This has been asked many, many times before. I answered one just few weeks ago.. so to get more comprehensive answer, use search (google search is better than reddit search..).
Mixing is merging multiple channels of audio to few. A regular rocktrio has around 8 channels of drums, 2-4 of guitars, 1 bass, one main vocals and 2-3 backing vocals. Each channel level has to be set in relation with the other channels or we call them, tracks (channel is more about the signal, track as a word comes from tape era where we had each channel recorded on their own track on tape). There are other signal processing like EQ and compressors (first controls frequency, the latter controls dynamics). After all this is done, we "bake the cake" or these days render the file so it has only two channels in stereo. Surround has of course more but that is not important detail.
But before it can get to consumer, we have one more step, mastering. In the early days, mastering engineer WAS the recording engineer. When we recorded direct to disc, they had to control the sound in real time so that it didn't exceed the format limits (mainly that it isn't too loud) but also so that background noise level compared to the signal level is correct. When we got magnetic tapes, we could do multiple takes and very soon, we could do multiple tracks too. In this era, the recording/mixing engineer was born and mastering engineer stepped in the shadows: they were responsible of making sure the material on the tape could be actually printed on vinyl disc. This also means the printing factory equipment, they were mastering for a specific carving machine. This also meant that they had to fix the different songs to be at least on same level, that one isn't louder than the other. Slowly, the role of mastering engineer turned more making artistic choices when trying to create an album, a work of art that is coherent and all the songs fit with each other, retains the band sound but also refines it.
Nowadays, mastering engineer is more about making the albums sound coherent and making the last bit of tweaks to that sound to make the band sound like they and the audience wants it to.. He serves as a mediator between the two but also serves as final technical check that the audio can be listened in all devices we use. In that sense, mastering engineer has returned back to the past and make technical masters. But since we don't need to do anymore per-factory technical masters, mastering engineer can sit in his studio and work with the "industry standard" (there are so many of them that there are no real standards but some have been more or less considered as such.. and for ex AES and EBU have done marvelous work in this area, former is engineers association and latter ie EU area national broadcasters association, both very influential and does wonderful research that we can all use).
Oh, and mastering engineers one of the most important functions for the band is that they serve as second set of ears. They are not intimitely connected to the project, they do not know the details: how that basslick took multiple takes to make or how the guitar solo was created in a magical settings, afterwards you all went to bar and had a great night (thus, the solo is raised more in front that it maybe should be...because of stuff that is not audible but only exist in the musicians memory). Remove those emotional connect and knowledge of history, they are listening it with fresh ears and can usually provide accurate feedback of ..."THIS is important in this particular song and not THAT" (this is why bands use producers but mastering engineers opinion is often heard, there are also often technical reasons that require retracking or remixing to better fit the target customers devices). But they won't try to fix the song, you can't do that in this point in time, what is done is done and you can't polish shit. You can only elevate some elements and hide some but it is more a shade of color than a repaint.
Ok, this became too long and comprehensive anyway.. But really, this question is asked about once a month. | 4054f4bf-ab7f-4a69-a497-4d15be54cd98 |
cebu8l | Why do some song birds appear to intentionally dive or swoop in front of moving vehicles? | Maybe they get some kind of speed boost from the air moving past? | d6789afb-dd61-4cec-a940-73668ce17d71 |
cebwg5 | What exactly is the Hatch Act? | The Hatch Act prohibits most executive branch employees from engaging in partisan political activity as part of their official duties. Spending money on a political campaign is something totally different and I'm not sure why you think they're related. | c7e7f8e6-e61b-4a01-a11d-3e0986c3222b |
cec1j4 | why dont factories have green houses to suck up their co2 emissions and create oxygen? | Way to much CO2 to be absorbed by a simple little green house. If you ever worked in a factory and saw how much waste they produce and scale it for CO2 emissions you get a feel for how much they blow out there. Also most emissions are really contaminated with not juat co2, which would kill off the plants | e0b774d5-8ec0-4921-a90a-b67fb35984ed |
cec4py | If fluorine is such a dangerous substance, why is fluoride, a derivative, not similarly dangerous? How do you safely add fluoride to water, and why is it beneficial for teeth? | Because compounds and their constituent elements are different.
Hydrogen and Oxygen will, separately, readily combust in a fiery explosion. However, that explosion happens simply because water is way more stable than Hydrogen and Oxygen separately. Once they're bound up in water, they can no longer make that transition from unstable to stable and release a bunch of energy.
Fluorine is dangerous because it is *extremely* reactive. It will react with basically anything. However, in fluoride, the Fluorine has already reacted with something (and then been placed in something that dissolves the compound like water).
To get the slightest bit into the chemistry: Fluorine is extremely electronegative, meaning it is extremely prone to pull an electron off of other chemicals around it. Fluoride is Fluorine after it has already pulled an electron off of something and is much more stable. | 4d474021-4a1e-4ac6-beb9-8ade398d3ce0 |
cecl0k | The Greek naming dispute with the, now, Republic of North Macedonia | The problem is that the term "Macedonian" has some baggage beyond just the region. Makedon was a hellenic kingdom that Alexander the Great hailed from. Makedon was Greek speaking and Greek in culture. Their capital was Pella, which today is situated near Thessaloniki in Greece. North Macedonians are actually from a Slavic tribe that was granted permission to settle on the outskirts of the Byzantine empire by the emperor. When these Slavs started calling their country Macedonia, the controversy started about what Macedonia actually was. This was further exacerbated by the fact that Macedonians started to also claim that Alexander was a national hero of theirs. Most historians would agree that the Slavic Macedonia has no connection with ancient Makedon, but they kept the name anyway. So that's essentially the story behind the controversy. | e3dfa576-984d-4709-8bba-b015abc84912 |
cecsl8 | How does soap work? Does it kill the bacteria present on our skin? | Soap is an emulsifier, which allows oil and water to mix. The bacteria on your hands are clinging to/living in the natural oils on your hands, and the soap allows the water to mix with the oils and wash the bacteria away. | e86186eb-b54e-4b72-9d83-2e8a65226447 |
cecxf0 | Why isn't there more text message spam? | Because an email costs some indescribably small amount of money in electricity and internet connection to send (or, potentially, in access to a botnet), but an SMS has a standard fixed cost. You can't just make random people who you're spamming pay for the message you just gave them, so you'd be forced to pay for it. $0.03 is not a worthwhile price for exposure to one pair of eyes to a bullshit scheme you're trying to push. | 48fbc220-a787-4b9f-aa80-cc2610f106a4 |
cecylt | how can China grant insane subsidies to factories and businesses that allow selling and shipping goods across the world for little to almost nothing and still make massive profits? | There's a few reasons:
Capitalism: China isn't it. The government is in control and can do whatever it wants to any company it wants, and it does. "massive profits" is a confusing idea in China. It's not wrong, but its definitely not right either.
Currency and costs: China uses some methods to artificially keep the value of its currency low, which helps it sell on the international market for very cheap. /additionally, the costs of manufacturing in labor in China is crazy low, although its substantially rising and places like SE Asia and East Africa, which are even cheaper are now competing with them in this sector.
Shipping/subsidizing: China is willing to lose money on stuff like this because they want to corner the market on this type of activity. They are not playing nice or fair, by design. The government is fine with subsidizing it, because it keeps them on top, again they don't care about making money, thats not their goal. They are looking to build and control.
The people: China has a different relationship with its people than western countries. China is happy to keep people making low wages and 'bad' jobs for now, most of the issue you bring up, the biggest people hurt are the chinese people themselves | 7313fb53-edc4-4e6f-b75f-e37196a13985 |
ced5xr | Why does starting or cancelling a print job seem to take so long? | Printers are truly awful, and mainly because they are different from other pieces of tech in that they cannot be fully virtual. Transistors can flick on and off incredibly quickly, so sending information across the world digitally is very efficient.
But a printer is basically a mechanical pen that has a small computer "driving" it over a sheet of paper. Moving parts are slow, prone to malfunction and they can break or jam depending on the conditions. So printers have a very difficult time doing anything. The software cancelling the job is probably managing fine, but the physical components, the various hardware checks and monitors and so on, are slowing down the process. | 06050532-9b2f-4c41-8bf2-d81580f33777 |
ceddws | Why are we feeling tingles when we know that a bug is nearby? | Anticipation. You anticipate, expect them to land on you so your touch sensation is primed to find exactly that kind of feeling. Which in turn makes us hypersensitive towards light touch and you even get phantom sensations. You are primed to sense the tiniest winger thing landing on you and you are making lot of false positives. Evolutionary, false positives are better than the opposite: it is much better that you shake a bit without any reason than having an insect sucking your blood. Thinking about a sensation will prime you for that sensation. Does your back itch? How about now, does your back itch.. just between shoulder blades the shirt is touching your skin, just a bit irritating, isn't it? That is about the same as thinking that an insect will land on you, you will notice a piece of hair or dust falling on you while normally you would not. | 7ef68989-7f8a-439b-948f-3486324d1e21 |
cedm15 | How does software control hardware? | The pin is wired to a driver transistor inside the chip. That transistor is like a switch, it connects the "power" pin to the "output" pin when the gate voltage is high. The transistor's gate is connected to one output bit of an output latch that's addressable in the computer's memory or I/O address space. The software writes a value into the latch's location, and the latch turns the appropriate control wires on, potentially including the one that controls the driver transistor. | 9dd95930-84e9-4903-8a8f-c923ee455da7 |
ceex2d | how did Einstein realize that light will bend near heavy objects? | Edit -- I'm leaving my original answer below but user @missle636 points out that this was not his original thought experiment. [_URL_0_](_URL_1_)
\----
You don’t need math to understand this. Here was Einstein's thought experiment.
Start with the Equivalence Principle (EP), which (essentially) states that acceleration and gravity are the same thing. Einstein came up with this as follows:
1. You are in a windowless box
2. The box has a rocket attached, which is firing, so you are accelerating.
3. Because you are accelerating you feel a force on your feet.
Now, how can you tell the difference between the force you feel in an accelerating box and the force you feel due to gravity standing on a rock? Einstein concluded that you can't, hence the EP. Scientists use their sciences to test the EP and so far it appears to check out.
Now consider this
1. You are in a box in space that has a window
2. Someone shines a laser through the window straight across.
3. If you are not moving relative to the source, the laser beam goes straight across your box.
4. If you are moving at constant velocity relative to source, the light beam still moves in a strait line, but will contact the other wall opposite the window “lower down” towards the direction opposite of motion, since the box is moving and it takes time for light to cross your box.
Here’s the important one
5. If you are accelerating relative to source, the light appears to follow a curved line through your box.
Go back to the EP. Since gravity and acceleration are the same, light must curve under gravity. Note this is NOT a proof, just a line of reasoning that points to the conclusion. The math came next and then the experimental verification.
Edit
heres a crappy picture I drew to help illustrate
[_URL_2_](_URL_2_)
Second Edit -- holy crap my first Gold!!! Thank you kind benefactor for bequeathing me this great honor. | 34101a7e-dc46-43ea-904c-b3d3c201aadf |
cefexz | What's a shell, subshell, an orbital in an atom? What's the difference between them and an orbit? | A shell is the area around an atoms nucleus where electrons spend most of their time. Shell and orbit are the same thing.
There are 4 'sub-shells' that can make up a 'full shell' : s, p, d and f. Not all are used though, so the first 'main' shell is just an s 'sub shell' and the second 'main' shell is an s and p sub shell.
An orbital is the space in the atom where we are lost likely to find an electron. Electrons are, for want of a better word, bonkers things! They dont behave like anything we can imagine and behave like particles and waves at the same time. For this reason, scientists often refer to the probability of an electron being in a space rather than actually describing where an electron is in at atom. This is where orbitals come in and they can house 2 electrons. The s sub shell is made of 1 orbital, whereas the p sub shell is made of three orbitals.
Very basically: shell/orbit > sub shell > orbital | 772c422a-a613-4d8e-82c5-58eb4be0fa35 |
cefy0t | Why does Humidity make the temperature feel 20 Degrees hotter? | High humidity means that sweating is less efficient. That makes it a lot harder for your body to cool itself down. | 058995bc-7841-4636-9a3c-3a046a88eb93 |
cefy6j | How is Cooking Oil Made? | Take seed or fruit. Grind it. Collect oil. Vegetable oil
Cooking oil is made from corn, sunflower, peanut, rapeseed (canola)
Or alternatively rendered animal fat. Beef fat makes tallow, pig fat makes lard. | f5820141-163c-40af-b8cf-d327c60fb0e3 |
cefyvh | Why do inflatable balls lose air over time? | They tend to be inflated to a pressure higher than the normal air outside the ball. So there is always air trying to escape. It will find a way especially if the air temperature cools down, with less pressure, holes that might have been smushed shut might relax and open. It can also happen if the temperature increases which will increase the volume of air in side the ball and could force holes open. | 02a5322d-413b-42b3-82b0-46cfeb190241 |
ceg85f | Why does the East coast of Canada get so much colder and get so much more snow than Southern/Central Europe that it lines up with on a map? | [The Gulf Stream](_URL_0_)
> The Gulf Stream influences the climate of the east coast of North America from Florida to Newfoundland, and the west coast of Europe. Although there has been recent debate, there is consensus that the climate of Western Europe and Northern Europe is warmer than it would otherwise be due to the North Atlantic drift which is the northeastern section of the Gulf Stream. | 8d641ec5-96f0-4393-ae75-88d9199cae24 |
cegjqc | Why does CGI in recent movies not seem as realistic/detailed as Avatar (2009) with recent developments in filmmaking and computer animation? | I think part of it was that almost every bit of every scene in Avatar was CG, so there wasn't as much of a chance for anything to be obviously out of place. When there's just one CG element in the scene, it can be really obvious and look really fake. | 696f0bec-74f9-43d1-9bbe-3541077136ca |
ceglc0 | why does stretching feel so good when you’re tired? | Sometimes it s just stress making muscles tense or rigid on a certain position . When you stretch, you change that position, relaxing the muscles a bit.
Being good/better physically usually translates into a "feeling good" in your mind, if that's what you mean. | 8817deea-a979-4ae7-8527-cbe914c7d444 |
cegrrl | why dont acids and bases melt through the containers they are kept in? is there an acid/base that could potentially be so strong it melts through everything and just finds its way to the center of the earth? | For the container, they are kept in nonreactive things, like glass. As far as the strength to melt to the center of the earth, in theory yes. You would just need lots of it no matter how strong it is. It also may need some help getting through water tables.
If you mix 14 and 0 yes it becomes 7. But that doesn’t not mean it is safe to eat | 934c6475-dced-4713-a587-774bada23572 |
cegsmi | Why exactly does inflation happen? | Can you be more specific? What type of inflation are you talking about? | ad873027-6924-481e-acc9-52fee43ebdbe |
ceh3qz | how do media agencies quickly find video clips in all of the media that’s been recorded over the last few decades? | They have metadata for all the clips in their libraries. They search the metadata and then look at the matching clips. So, they're not searching "all the video clips" but rather "all the clips they have".
After that, it's all Google/YouTube. | 069f5743-dc35-407c-bb9b-801c618e2ab4 |
ceh5yr | The standard model | There is probably not a ready ELI5 answer to that question, but the short answer is that it's the general schematic for particle physics, via its explanations of three fundamental forces and the subatomic particles which make up the universe and interact via those three forces.
It is incomplete; there is no Standard Model accounting of gravity. | 3c8a53e0-9ebe-4b36-a0ee-fb8635296333 |
ceh7hu | why is it better to be relaxed than tense if falling from heights? | It's like the same thing as you can break spogotter but then u be cooking teh spogotter and then u cannot break it anymoar | 67671f9a-1a70-4167-ae58-a59173f29203 |
cehmfk | The difference in the sun's effects on Jupiter vs Earth. 4x distant, 318x massive. How does the sun keep both planets in orbit without that same gravity pulling the closer, smaller, less massive Earth to its doom? My brain says the speed of orbit helps, but HOW? | You first need to understand what an orbit really is. Imagine you are firing a canon. The ball will go to a certain speed and gravity will slowly attract it to the ground. The acceleration of gravity is always the same so if it take 2 seconds for the ball to drop to the ground, it will always be 2 seconds. If your canon is weak, the ball could travel 100 meters in that 2 seconds before it touch the ground. If your canon is stronger maybe your ball will travel 100 km in that 2 seconds. In those example, the kinetic energy the canon put into the ball is less than the gravity so the ball will touch the ground.
& #x200B;
But now imagine that your canon is like really really strong. Your ball go so fast, that it go further than the curvature of the earth, so the ball fall off the Earth. Now your ball is in orbit, meaning that it keep falling toward the earth because of gravity, but the sideways speed is so fast, that the ball keep missing the ground.
& #x200B;
If you looked at the formula for the equilibrium between gravity and kinetic energy, you would see that the mass of the object cancel each other out in the formula. So the mass of the object in orbit doesn't really matter at all in that equilibrium, only the speed and the gravitational force of the central object (which is the Sun in our situation) matter. And since the gravitational force of the Sun change depending on the distance, you can see that the further away from the Sun you are the slower your orbit need to be to reach equilibrium.
& #x200B;
You can kind of see the same thing with figure skaters. When they spin and start to put their arm closer to their body, their speed of rotation increase to keep their rotational momentum, they keep their equilibrium by exchanging distance for speed. It's not really that same things, because it's not really the same forces that are involved, but the principle stay the same and it make it easier to understand since it's easier to look at a figure skaters, than a orbit of a planet.
& #x200B;
So if you look at the Earth, it have an orbital speed of 29.78 km/s on average, while Jupiter have an average orbital speed of 13.07 km/s. It's further away, but slower. And if you look at Mercury it's closer to the Sun so it's orbital speed is faster at 47.7 km/s.
& #x200B;
So yes, the mass of the object doesn't matter. The Earth could be the mass of Jupiter and still have the same orbit at roughly the same orbital speed as it have right now. | a65cbe18-609b-45a2-aefd-7887dfc96bf6 |
cehmoq | Why haven't we been back to the moon in almost 50 years? | Why would we?
That's the multi-million dollar question right there.
There is no scientific, economic, or political reason to send a manned mission[s] to the moon. Pretty much anything we could ever need done could be done with automated robots more easily anyways. | 0b8e8c42-cb87-4088-98f5-d2ae175b1581 |
cehrs6 | Why is it so hard for juries to convict a police officer when they shoot an unarmed civilian and there is clear evidence of excessive force? | Self-defense laws are often intentionally worded to allow for some error in judgement, and specifically create the standard that "feared for your life" is a good enough reason to use deadly force, even if you were wrong.
This is setup is honestly for a good reason. Lets say I break into your house in the middle of the night, and am armed with either an unloaded gun or a realistic looking toy gun. Technically you were in no danger from that weapon, but you shot and killed me... The law can't cater to specific situations without creating more problems, so they give this lee-way.
Meanwhile laws establishing police authority are often at conflict with regular criminal charges such as manslaughter, specifically because they grant powers to take away freedoms or take a life as part of the job. So proving that a cop was wrongful in their actions often requires the prosecution to demonstrate a clear and specific malice (I really wanted to kill that guy), versus just plain on "got scared and shot the dude".
Finally, throw in the fact that in general people still tend to trust the cops, and it becomes a monumental task to convict an officer. A trial like that can cost the tax payers a lot of money, and knowing up front that you basically need a video of the officer saying "Man, I sure do want to kill me somebody today" to get a conviction, and it becomes not really worth the trouble to prosecute. | 9a354199-60a4-4333-b55f-83597b79868e |
cehvmj | How come sometimes your teeth hurt right away after eating something super sweet? | A cavity, enamel loss, damage to teeth which leads to microscopically exposed nerves etc.
Your teeth should not hurt when you are eating sweets. Ask a dentist. Like, quickly. | 23b69763-a578-476c-97f1-5d12be53ff4e |
cei83g | How does clicking a box actually confirm that you're not a robot? | It looks at how you click it. If you instantly move the mouse to the location and click it then it can be suspicious of it being a program instead of a user with a mouse. If the movements are suspicious then it makes you go through a special type of captcha, an identification captcha (like where it has a picture of a street and asks you to select every frame with a car in it). While it would be possible to program an AI to not only click but also solve these captchas, due to the sheer potential variance in the number of potential tests it can do it would be difficult to create any form of reliable bot. | 32dc9634-9d38-4a1d-b4ec-f125d97995c8 |
ceid4n | What is an API? | It probably seems like they're talking about a different thing because an API is just a broad concept and the specifics of what form it takes can vary significantly.
An API is whatever method a programmer uses to interact with something. That something could be some other software, it could be a web service, it could be some hardware, it could be an operating system.
APIs come in many forms. Often they are programming libraries containing functions for some programming language. It could be a web based API where programmers have to send messages to a particular URL. Even a program that takes command line arguments could be considered a sort of API because you could make a program which calls that other programmer. | 1473e924-430d-4b5a-8aa6-901eb4ed6526 |
ceiebr | Why do some plants have sweet fruits which makes you want to eat it, but at the same time thorns that stops you from eating it? | The thorns make it harder to eat the plant especially for large animals. At the same time small animals like birds that can fly far can eat them without any problem. The design of plant is a compromise between spreading seeds and not getting eaten. For extreme plant like cactus there is some animal that can eat the fruit and it is often birds.
Another example is chili pepper that contain capsaicin taste strong to mammals that would chew and destroy the soft seeds. Birds can't taste capsaicin and have cannot chew because they have no teeth. So birds it the chili fruit and spread the sees without damaged it. So instead of hard seeds like some plants it have a evolved the capsaicin and use only birds to spread them. | cb815c5f-4f20-4210-b350-325f41d0a4cd |
ceihl6 | Why do tires need to be hollow and filled with air? Why can't they just be filled in with rubber? | Air weighs less than rubber. Rubber costs more than empty space. The ride quality would be worse. But there are some interesting designs for airless tires that may revolutionize how we design tires. | 9ec68b87-d4c8-495b-b08d-2d6fee4bc384 |
ceiok2 | We often see animals "adopting" and feeding babies from other species. How come the babies don't die from "malnutrition"? Is the milk of any mammal suitable for any other mammal? | Technically milk from any mammal is not the same for any mammal, as cow and goat milk is not enough to sustain a newborn baby. I believe it varies between humans and animals. Human breastmilk is designed for humans and humans alone. Maybe animal milk is more universal and made up of the same basic proteins so that animal species can adapt fairly well without a nutritional loss. I imagine the amount of time dependent on milk is also a factor, as animals are eating solids within a few weeks to months, whereas humans need breastmilk for the first year and do not rely on solids until after that. | f93e34fe-6bb9-468b-a773-2ee4178010d4 |
ceixog | What’s the difference between a municipal area and a metropolitan area? | A municipal area is defined by law with strict boundaries. Basically if any city has certain ordinances or taxes then that applies to those lviing in the municipal area.
Metropolitan area is kinda more fuzzy as it looks on how people interact in a region. for example where they live and where they work, or shop, etc.. | 71f357c0-d342-4a52-a5c6-9c794c07123a |
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