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c2jn5q | Why are we sometimes unable to fall asleep when tired even in pristine conditions? | It's just how some people's bodies work, and it also depends on what you were doing before hand. If you were on your phone you are getting blue light which lowers the amount of melatonin you get which helps you sleep. Also, some people could just be bored and not really needing to sleep. For example, I could be at school, fully awake the hour before having fun with my friends, but now I'm in biology with Mr. Monotone and I'm dead tired, but Lunch is next and I'm fully awake again. Sleeping is a weird process, it's insanely easy for some to fall asleep, and very hard for others. Try googling things you can do before bed time that can help you sleep quicker. | e9c65575-3af9-4c6c-b67a-36e862685960 |
c2jnmd | - How does a single 3.5 mm jack provide stereo sound? | You will notice black bands on the jack. Stereo will have 2 bands, making 3 connections; L, R, and common. Some new headphones with buttons will have extra bands. | 166744f1-61a4-4d55-9efa-f97b79fa94bb |
c2jrxf | if every cell in your body gets replaced over time, how does your brain maintain memories? | Neurons that compose memories do not normally die and are not replaced by newly forming cells. The cell is replaced in the sense that sooner or later every molecule is swapped out as a normal part of cellular maintenance but the entire cell is never replaced all at once.
Think of a car for example. A normal cell dying would be like a car exploding so you buy a new one. For neurons, its like replacing a wheel one day, the windshield the next, and the seats sometime after that. Sooner or later its a new car because the parts are replaced but it still operates the same and carries the same function. | 9ae8edf5-cbab-4aff-85f0-7d321447d18e |
c2jy5h | Why do flies have such good reflexes? | Firstly, flies are 100% reflex. There's no decision or second guessing; *everything* they do is the instinct of the moment.
Secondly, their eyes are *way* closer to their brains and wings than any bit of you is to any other bit. That distance matters, because it takes time for signals to get across it. Not much time, but it adds up. | 129c45c0-541b-44ae-bfc8-a3bd79af3035 |
c2k9zl | - Why as adults do our bodies wake us up to tell us to use the restroom, but not as toddlers or younger kids? | It's mostly neurological development, as well as learned muscle memory.
There are two reflex arc that govern urination. The micturation reflex, and the guarding reflex.
The micturation reflex is a subconscious reflex that we're born with. Your bladder wall has stretch receptors in it. As the bladder fills, the receptors at activated, and trigger two sets of neurons to fire. One set stimulates the bladder to contract, the other sends an inhibitor signal to the rhabdosphincter, telling it to relax. It also causes a collateral signal to be sent to the brain, to alert us as the bladder is filling. When the bladder is sufficiently full, this reflex kicks in, and attempts to empty the bladder.
This works in opposition to the guarding reflex. The guarding reflex maintains increased tone in the rhabdosphincter, and pelvic floor, when voluntary urination is not desired. This reflex is essentially absent during fetal development, and rapidly begins developing around birth.
Both of these reflexes can be overridden, to a degree, as our brains and muscles mature, and with practice. As we get better at it, our brain even learns to do it subconsciously. Eventually, most people even learn to do it in their sleep. Just as we learn as children how to differentiate pain from hunger or thirst, we learn the sensation for bladder urgency, and your subconscious taps the arousal neurons of the reticular activating center (part of the brain stem) to wakes you up when the urge is strong. | 733aa954-b80c-45a3-b6f0-332dfc586f52 |
c2khjt | Cortisol testing | Usually, we test for cortisol levels by using a 24-hour urine sample. It's pretty rare that we single out a specific time of day to sample cortisol because we're more concerned about the overall average levels in the body than necessarily those at a specific time (although it can be done with blood work if need be).
When we say that cortisol levels tend to be highest in the morning, it's an oversimplification. As you're implying, levels tend to follow the body's circadian rhythm, so when we say that they tend to be highest in the morning, we actually mean that cortisol levels tend to be highest approximately a half hour before you wake up.
So, if you wake up at 11 everyday, it's likely that your cortisol levels will peak around 10:30 a.m. After that, they'll generally follow the normal progression of any other person throughout the course of the day. | e248c7dd-c778-4edf-81c7-afb444b4c221 |
c2ksxa | Do spiders get stuck in the webs on other spiders? | Spiders thread non-sticky threads into their webs that they use to traverse the web safely. Other species and even members of the same species can get stuck in the web. They can get stuck in their *own* webs if they fall or get startled, but will chew their way free. Spiders eat their damaged webs to recycle the proteins.
Spiders are generally cannibals and will happily take care of any brothers and sisters that stray into their web. | cf6a13d4-a315-4a71-9f6a-df447e41385c |
c2lh5n | Why does the left side of the brain control the right side of the body, and vice versa? Why shouldn't each side of the brain control its respective side of the body? | Answering "why" questions is always difficult in cases like this because evolution doesn't have a "why" or "should". Often there is an obvious benefit to a characteristic, so it's easy to reason out "why", for example, our stomachs are acidic, but in cases like this it's far more difficult because there's no obvious benefit to things being this way.
Which is an arsey way of saying "we don't know". There's a characteristic of vertebrates (animals with an enclosed spinal cord) called 'decussation', which describes the way nerves "cross over" as they exit the brain. The result of this is that the left hemisphere of the brain controls the right side of the body and vice versa.
All vertebrates exhibit decussation, but the same is not true for invertebrates. So it's assumed that, at some point in the early evolutional pathway of the spine, it twisted 180°. We don't really know why this happened or why it was beneficial enough to be a universal characteristic of vertebrates, and while there are a few theories, they are very difficult to prove conclusively. | fceaa0cb-0818-4559-bf08-03d9927c4ff3 |
c2lhuy | How do plants grow from a tiny seed using just water and sunlight? | Usually, the seed provides enough nutrients for the (baby) plant to develop a small root system and the first couple leaves.
Once that's accomplished, the main mechanism for growth is [photosynthesis](_URL_0_). 6 water molecules + 6 carbon dioxide molecules - > 1 sugar molecule + 6 Oxygen (released).
The sugar is then assembled into chains to form [cellulose](_URL_1_), which is the main "fiber" / body of the plant as it grows. | d4c407f0-5ba6-4a8b-a9ea-98820ef1ad0c |
c2lhwr | - Why, after drinking a good cup of coffee, people have to take a nice, healthy defecation? | This only happens to folks who don't drink multiple cups of coffee a day. As a person who averages 3-5 cups on a weekday this doesn't happen to me ever, and I'm not unique. | 8fbf7c52-2d03-42f4-8c25-e086744f7a2e |
c2ljvl | Why do cars have a "power range" | This is explained by "volumetric efficiency". If we assume a particular temperature, volumetric efficiency can be taken as a a ratio of mass of air drawn into the engine vs. the theoretical mass-draw capacity of the engine. At the point of maximum torque, the engine’s volumetric efficiency is also the highest, meaning that the engine is sucking in the maximum mass or volume of air it possibly can. After this point in the RPM band, the torque reduces due to the air flow losses in the valves and mechanical losses which dominate at higher speeds. These factors reduce the volumetric efficiency and thereby the torque.
& #x200B;
Power continues to increase as it is a product of speed and torque. At one point closer to the engine’s upper RPM limit, the power peaks and starts to reduce as the rate of fall in torque is greater than the rate of increase in RPM. | 35f8757e-d98a-4065-bd37-9b654dc9cb68 |
c2lpxy | How can some companies offer unlimited cloud storage for an affordable monthly subscription while others charge an arm and a leg? | First off, that 'unlimited' remark us correct, they're just saying that assuming you'll never actually be a problem. All data stored on the cloud is actually kept on hard drives in servers somewhere. Some companies have their own, but a lot just rent server space from other companies that make giant server farms for this purpose. Amazon runs one of the largest server farms companies out there, called AWS. They can say unlimited because while your computer might have 1tb of storage and your phone might have several hundred gb, their servers will have billions.
It'd be like if I had a warehouse the size of ten football fields and rented 'unlimited' storage space to you. Realistically no one person is going to have enough stuff to fill the warehouse, even if you had several houses worth of furniture you needed to store, so it might as well be unlimited. Kind of like how buffets serve 'unlimited' food. It's not really infinite food, just more than one person could possibly eat. You might say that while one person could never fill that warehouse, a single company could, or that enough people could eat all the food at a buffet, which is true. If you look at those cloud providers, they probably offer personal use options and enterprise options, because they know businesses or large organizations will have a lot more storage needs. If they ever start to run out of space, they can always rent or buy more servers.
There's also differences in services offered. A cheap cloud solution might have a single site with comparatively low speeds, while a more expensive one might have your data backed up to several sites all around the country so even if an entire facility burns down your data is good. They might also have better upload/download speeds and security features, Alon with other stuff to justify the price.
A storage place that's just got a roll up door with a pad lock is going to be cheaper than one that's got cameras, climate control, guards at a gate, a forklift on site that can load and unload stuff for you, and other benefits. | 4036d79d-1319-4db3-ad81-3933459c2217 |
c2lxz4 | why cant different species breed with each other? If they both have sperm and ovum? | First, if the sperm cell surface markers are too different it won't even get into the egg. The key doesn't match the lock.
Provided you beat that, you have a half set of chromosomes and an entirely different half set with a different number of chromosomes and different gene placement. Nothing matches, the chromosomes can't pair off, and gene expression is catastrophically wrong. The fertilized egg fails to divide and dies.
You're shuffling half a deck of Uno cards into half a deck of Pokemon cards and trying to play a game. | 4711c112-d5bc-417a-b04f-4ab03c9bae66 |
c2lz1i | How do seconds, minutes and hours work on a map, and is it different from latitude and longitude? | Latitude and longitude are measured in degrees, minutes, and seconds. A degree is 1/360th of a full circle ie 1/360th of the way around the world at the equator. A minute is a sixtieth (1/60) of a degree (1/21600 of a circle), and a second is a sixtieth of a minute (1/1296000 of a circle).
Your longitude is how many degrees, minutes, and seconds you are from the Greenwich Meridian, normally given in conjunction with a compass direction (East or West) or a +/- sign (+ being East and - West by convention). Your latitude is how far away you are from the equator (North/+ or South/-). | d3585113-43e9-4ea5-8a54-5df92e1f7a03 |
c2m3ds | What's the difference between RJ-45, CAT5, CAT6, and Ethernet cables? | Ethernet cables are just a catch all term for eight-wire cables. They can be CAT5, CAT5e, CAT6, even CAT7.
CAT5/CAT5e/CAT6/etc. is a designation for the type of wire used in the cable, with higher numbers capable of handling higher speed with less interference issues at longer distances.
RJ45 is the designation of the jack at the end of the cable. | 1ab31dc2-1cb4-407e-a390-cda3f2177bdc |
c2m8w4 | I understand how neurotransmitters like serotonin, dopamine, norepinephrine affect mood, but how do hormones like estrogen, progesterone, and testosterone affect our moods? | This is a complicated issue and it differs for each person, but yes, these hormones affect neurotransmitter levels and act as neurotransmitters themselves. Estrogen is generally a mood elevator at best, but at worst makes you agitated. It’s a stimulant. Progesterone has a neuroprotective effect and at best makes you feel calm and relaxed, but at worst can cause deep depression. Testosterone is a mood elevator so can make you feel happy, confident, and energized, but at worst aggressive and angry. It also makes you horny.
A drop in estrogen or low estrogen can make you feel depressed and gray. High estrogen can make you feel emotional and agitated. Low progesterone can make you feel agitated and restless and give you insomnia. Low testosterone can make you have no sex drive and feel down. | af5ed57c-bb0b-44c3-af84-e4c844e4e869 |
c2mbfh | Why is the pressure at the center of the earth higher than on the surface? | Pressure is stuff pushing on you. If you stand on a chair vs hold a chair above your head there is a big different in amount of stuff pushing down on you (one chairs worth).
At the center of the earth there is one earths worth of stuff pushing down on you. | fe928fa1-2561-42e6-bb53-44d68d720d84 |
c2mfeg | How does the enigma bombe work? | It had a small list of common parts of messages. Trying every key, it sought a match. When it found one the key (dial settings etc) were tried on a whole message. If it worked, you had the key for that day's message group. | ccdd6668-60cf-420c-a672-71ce95388c1c |
c2mjma | How do they know how long my donated blood lasts before it is no longer usable? They told me it will be usable for 30 days, does it suddenly become unusable on day 31? Or does it slowly become less effective/usable? And how do they decide it? | A regulation is in place to make sure no one accidentally uses actual aged blood. So blood banks are only allowed to *have it available for use* for 30 days and then must dispose of it regardless of actual shelf life. | ad79a7ca-a41d-4250-b01c-97dfb692f963 |
c2mk5t | Why do ashes turn white on black things, but black on white things? | Ashes are a mix of calcium compounds (a white powder) and carbon (a black powder), along with some other stuff. It's generally a bunch of flakes which range from white to black and a full spectrum of gray in between.
On a white surface, the darker particles are visible. On a black surface, the lighter particles are visible. | 183e6e12-e32e-4712-ad88-edc86a643d47 |
c2moim | How do APR, interest rates, and billing cycles work? | You borrow money from the bank. That's credit. They expect you to pay it back with a 'fee' which is interest. APR is the annual rate of interest. If you borrow $100 for a year at $10 APR then you pay back $110.
It's not quite as simple as this in general because, with credit cards, interest stacks differently for purchases, cashback and balance transfers. So you might see a different rate for these items.
APR depends on risk. If you are risky to lend money to (you've been bankrupt) or banks don't know how risky you are (no credit history), you get a worse rate. Rates depend on your risk, your country's risk, the bank's risk appetite, etc.
Billing cycle is the period of time when they charge you. So you might get a bill at the end of June for everything you spent between the 7th of May to the 7th of June, which is the billing period. The cycle might be every 30 days, for example. | 0b105f36-60b9-4b4c-9e5f-ea6571abfba0 |
c2mq55 | How is antimatter created in particle accelerators? | They throw a lot of electrons really fast at a very dense target. The energy created in the collisions creates all sorts of things. When some of that energy turns back into mass, matter and antimatter is produced in equal amounts. | 7a1481cf-02a9-4350-8ee4-689939ac666c |
c2ms0j | when you open a website and it informs you it’s using “cookies” what are those, what do they mean, and are they harmful to your computer? | Answer: A cookie is a way to see where else you have been online. Think of it as breadcrumbs instead, and everytime you go to a website you leave a crumb behind. The problem with cookies online is they allow you to be tracked and have ads customized to you. Some people see this as an invasion of privacy. But it does not harm your computer.
For example, if you went to Amazon and you were looking for holiday cards, and then went to Facebook have you ever noticed that Facebook ads have holiday cards on them? That's because Facebook was able to follow your crumbs back to Amazon and see what you were looking at, and use that information to better market products to you. | a8f8a15e-f756-4ce8-a14a-0d41f14d79d1 |
c2msri | Why are hospital staff trained to work 12-24 hour shifts whereas most other occupations work 9-5 pm? | There is a ton of information about patients that needs to be passed from one shift to the next. This takes a good chunk of time, during which both the outgoing and incoming staffers aren't proving patient care. And, during hand-offs there are always going to be some details that get overlooked; hopefully nothing major, but minor things that still might make patient care better. For both these reasons, its better when there are fewer shift changes. | e3cbc682-3a27-4598-a600-50dc5502c7a3 |
c2mxhl | What is the uncanny valley? | The "uncanny valley" describes a graph like [this one,](_URL_0_) showing how humans react emotionally to things that start to resemble humans. The valley itself is the dip that the graph takes as we get closer to a human likeness, showing that humans are most uncomfortable or scared of things that look *almost,* but not quite, human.
And it's easy to see this in action! Take a look at some YouTube videos of humanoid robots - odds are that the ones that are *nearly* human and trying to emulate human behavior, like the ones with fake skin that can make human facial expressions, will make you a little bit uncomfortable, or look a little bit creepy. Seeing a human do those things wouldn't creep us out, and seeing a robot that looks less human (like one without skin, or without a human shape) won't creep us out too much. But as you approach that point of being nearly human in appearance, those little details that are wrong start to stick out and make us uncomfortable.
That's also the key to a lot of horror, honestly. Zombies and vampires are scary to us because they look nearly human, maybe could be mistaken for a human at first. But the things that are different about them - the rotting skin and shambling walk of a zombie, or the fangs and lack of reflection of a vampire - trigger our fear instincts pretty well. Same thing with a witch, or a human doll that comes to life, or an alien disguised as a human, or any other number of human tropes. When something is just a little off from perfectly human, it falls into that valley and makes us uneasy. | 1f9514df-3c6a-4b81-bb25-e2b7d00f3b49 |
c2n5dv | - How do those labour simulators work, and are they safe? | So a labor simulator uses electric pads that are placed over specific abdominal muscles. When activated, they send an electric signal to the muscle causing the muscle to contract in much the same way that your brain sends an electric signal to your muscles. To simulate labor, the machine causes the muscles to react in the same way that they would during a contraction.
They are safe, though they would make you sore for a few days after. I wouldn't reccomend it because first, contractions fucking hurt (can't move, can't breathe kind of hurt) and second, they aren't a fully realistic representation of labor anyways. | 6d6bc6d2-6826-4aec-8d8a-b091098a2fc3 |
c2n66l | - What makes someone a morning person? And the same with night owls? Is there a scientific explanation behind being one or the other or is it simply a lifestyle choice? | The scientific concept is 'circadian rhythm' - basically you have an inner clock that gives you a sense for the time of day. Unfortunately for most people, the inner clock is not set to 24 hours exactly.
If you have a short circadian rhythm, you are likely a morning person because your subjective days are shorter and don't require that much sleep - on the other hand a long evening will feel wrong for you much quicker.
With a longer circadian rhythm you are likely an evening person. Your rhythm demands a longer night than reality can provide, so you will rise late and/or fight drowsiness. You can go much longer in the evenings though because in your rhythm barely a part of the day has passed. | 96716271-148b-483a-9345-3013a65619d0 |
c2nahh | How does calcium strengthen our bones? | Calcium in our bones is actually a composition which is very hard. Without it, bones resemble something like the cartilage in your nose. The best ELI5 I can give is for you to test it yourself:
- buy chicken wings with bones.
- eat
- dunk bones in vinegar overnight or so.
- acids dissolve the calcium, and the bone is no longer rugged.
- bend the bone like a rubber band :)
Contrary:
- safely hold the bones over a hot flame (eg. stove).
- flame burns cartilage-like stuff.
- break bone with absolutely zero effort :)
The lesson here: bone strength is not only due to calcium, the strength comes through flexibility also. Otherwise, they would be very brittle, like a crayon.
Try the above, let me know your findings :)
Edit: thousand edits, non-native speaking mobile user+autocorrect | 6df2f35d-132a-4a88-88ae-ac13d66b89e4 |
c2njng | why you can chug almost all drinks, yet alcohol is so hard to chug. | Not always, if you mix up a good cocktail without too much bubbles it's not too hard to chug | 3652afa9-ee1d-415b-8b53-0ffeca3ec51c |
c2nk7t | Why do household smoke alarms use D batteries instead of the more common AA batteries? | D-cell batteries last longer.
Every smoke detector I've ever seen used 9-volt batteries though. | e770ef28-6e9c-4ca8-bfd8-6d5a1c1c232b |
c2norp | Why does going 100mph in a car feel so much faster than going 500mph on an airplane? | Because of parallax, which causes things that are closer to appear to be moving faster that those farther away, even if moving at the same speed.
In a car, the stuff you're looking at to judge your speed (road markings, plants on the side of the road, etc) are only a few tens of meters away. In a plane, you're kilometers above the ground, so even though you're moving much faster, the stuff on the ground doesn't seem to be moving much at all, making it seem like you're barely moving. | a41d117d-f7b5-446e-9e73-56dd93c2c8d7 |
c2onyq | - What are antioxidants? | Antioxidants are compounds that were thought bind to "free radicals" and render them inert. In the same way iron "oxidizes" and turns to rust, compounds within the body degrade over time, releasing free radicals, which cause cell damage because they are looking for an atom to complete their outer layer of electrons. Free radicals can be absorbed or ingested, as well as created within the body. A lot of airborne pollutants increase free radicals. Antioxidants were thought to bind to these free radicals and allow them to be exhaled or excreted. This science has not been proven to have any health benefit, however. Foods that are high in antioxidants are generally healthful, but the antioxidants themselves have not been proven to have health benefits. | fb4bdb08-521f-4595-927f-b67ebd1babfb |
c2opi7 | How do satellites work? (In relation to getting internet on a ship) | The relay signals between the ship and a grund station on earth that it connects to the internet.
The simplest variant is that they receive a signal from the ground station and re transmitter it in another frequency to a large geographic area. The do the same with the signals transmitted to the ships and transmitter it to the ground station.
The signal to the ground station have a narrow beam as it only need reach a single point but the signal to the ship will cover a large area. | 461fb72f-6b5e-48c5-a59d-41224290d423 |
c2orbp | How does chameleons know what color to change and how they do they change? | Chameleons don't actually use their color change for camoflauge much.
They use it for social signalling, and reaction to temperature.
So it's kinda like how you "know" to turn your skin red when you are cold or embarassed.
It's a reaction to internal physical processes.
Chameleons actually change color by using tiny crystals of guinine in their skin.
By moving them closer together or further apart they change how light bounces off the crystals, and thus change color. | f969d389-8402-425d-8f0f-6ea25523c793 |
c2oyfp | If the sensation of heat is molecules of high-energy colliding with your skin, why is wind, or moving at high-speeds through stationary air, cold? | Because the [average speed of any random air molecule is 1,520 ft/s](_URL_0_), or ~1,036 mph. Wind speed is negligible in comparison. | 0103c530-9a36-4620-b334-0598fa440c13 |
c2p7j5 | When guys inject testosterone they get bigger muscles etc. What happens if girls inject estrogen? | Limited experience, but in the condition poly-cystic ovary syndrome (PCOS), there are large cysts in your ovaries that produce extra estrogen and progesterone.
Your liver then turns all that estrogen into... testosterone! There's other complications, but one thing that happens is excess androgen production. This effect (even if you inject estrogen for menopause) increases your risk of everything from heart attacks to dementia to some cancers (though it may lower breast cancer risk).
So along with what other people say, in excess, it can cause masculinization. | b3d56cad-047c-4299-bf98-0dee827e1c33 |
c2pz1b | How does clearing your throat improves your voice when your vocal cords are much further down in the larynx? | Usually clearing your throat gets rid of liquid sitting on top of your airway which makes your voice sound clearer. | c31954fe-c4f1-480d-8bc1-7395fe5128de |
c2q2ux | How is Amazon able to get away with paying so little tax? | It's a combination of things, but usually in these cases it's a mixture of carry-over losses and tax breaks from jurisdictions that are trying to curry favor with the company in order to convince them to stay in the area.
To expand on that, companies are only required to pay taxes on profits, not pure income. Many companies, especially during their early years, do not make a profit and often run tremendous losses. Obviously they do not pay any tax during these times, plus they are able to avoid paying taxes in the future as long as the profits they make in the future are still less than the losses they incurred in the earlier periods. This can often lead to many years of little or no taxes for many years, as they recoup the earlier losses.
And then, like I said, cities and localities will often give tax breaks to large companies in order to convince them to stay put in their city because it's beneficial to the city in other ways beside the potential tax benefits. They provide jobs and make the city appear more successful and progressive, leading to further gains with other industries. | 006188b4-e8a7-4ac5-8be5-1269fac1736d |
c2q6lv | You see in movies/TV often where someone has a clear cut lawsuit against a company, but find out “they have million dollar lawyers that will tie you up in court and bankrupt you in fees” How much of that is reality versus Hollywood? | A little true, a little false. Thing thing about large companies is that they don't want to pay those million dollar lawyers either. They will always take the cheaper option. If a lawsuit is totally false, but they have to pay those million dollar lawyers to prove it, most big companies will settle and pay someone who does not deserve it because it's the cheaper option. Conversely, if the lawsuit is a huge one and paying those million dollar lawyars is cheaper, they will do that. It's all about the dollar signs.
Sometimes the big corporations are actually at a disadvantage, because they have to pay their lawyers out of pocket, while lawyers specializing in lawsuits will work for nothing unless they win if they are confident of winning. The plaintiff in that case has nothing to lose.
So--it depends. | 190d5082-edb3-4251-b8d0-d444aba82df4 |
c2q97h | Where and how does all the debt people need to pay go when they eventually pass away? | When someone dies, all of their stuff is bundled up as their "estate", it's all their money, things, property, and other assets
From this estate any outstanding debts are paid. If there is stuff left over then it gets inherited by those called out in the will.
If they had more in debts than the estate is worth then no one gets to inherit anything and any remaining debts are just written off. | a500f31e-e2ff-446d-94de-99b799ff5b20 |
c2qfo4 | If the human body is constantly reproducing cells (including skin), then why don’t tattoos completely disappear 7ish years after getting them? | The outer layer of your skin regenerates and replaces dead cells, however, the inner layer is protected and does not regenerate at the rate that the outer layer does. Tattoo ink is deposited to the inner layer.
Tattoos DO fade over time and need touch ups. Also, if the tattoo is too shallow, the ink “falls out” and the tattoo will need redoing/a strong touch up. | 8a1f7f16-352b-42ed-8597-360be888edaf |
c2qg81 | If zero times anything is zero, and infinity times anything is infinity, then what is zero times infinity? | "Infinity" is not an element of the standard real number system, so if you want to say something like "infinity times anything is infinity", you have to choose an alternate system of numbers that actually includes infinite values. There are several of these, which appear in different areas. Using the extended real numbers, which includes points +infinity and -infinity at either end of the real number line, 0 \* +infinity and 0 \* -infinity are simply undefined. Using the cardinal numbers of set theory, there are many different infinite values, but you still have x \* 0 = 0 for any x, whether finite or infinite. As with anything in mathematics, you have to be precise about what you mean by "zero times infinity" before you can talk about it. | 9a328a27-c311-40cb-b1c5-3d5db8dfd730 |
c2qkof | Who “owns” the GPS system? | The "GPS" system is owned and operated by the US Air Force. It is managed by the 50th Space Wing, Schriever Air Force Base, Colorado.
& #x200B;
There are other satellite navigation systems that are run by other countries. | 98e68936-05d1-4adf-a440-34a041cd5d95 |
c2qlt6 | How does our brain know precisely how much strength to use, or not use, when throwing an object a desired distance? We can generally get it pretty close to where we want even if we’ve never thrown it to this spot before. | Practice. You’ve never thrown it to that spot. And maybe you’ve never thrown that object. But you’ve thrown other objects at other spots. So your brain makes a prediction that you are able to implement. | 62d6b64e-b45f-4348-b151-2f1ebb64d7e2 |
c2qmgm | Why does the sound of running water make people need to pee? | Association.
When you pee it sounds like rushing water. Then when you hear rushing water you think pee.
Its how advertising works. | 08a83a3a-987b-4cc8-a078-3f06f3322dff |
c2qof7 | How do people stand on airplane wings when airplanes go so fast | People don't stand on airplane wings while they are flying, any more.
It used to be a stunt, called "wing walking", but that was in the years of slow flying biplanes. The stunt people had wires to hold them in the wind, but these planes had a speed between 50 and 60 MPH (85-100 km/h). | dbb07df9-65f7-4570-aa72-6fce841d05c3 |
c2r433 | How do baby birds just know that they need to break free from their eggs, which would be the only place they have ever known? | Instinct. Same as why a baby sea turtle crawls to the ocean, or a baby duck follows it's Mom around or any mammal that knows to suck on it's mother's teet for milk. | 408e8cb1-72c3-4b51-95eb-5629f5d64e24 |
c2r4a1 | Why do some products require refrigeration after opening, but can be on a shelf for long periods of time prior to? | An item can be packed in such a way that specific conditions are maintained: such as the content being completely free of bacteria or not containing oxygen gas.
Once opened, those conditions can no longer be upheld, and microbial growth and/or oxygen exposure will lead to product spoilage much quicker. | e39e54e3-1f2f-4894-b87a-4fd3c9e22127 |
c2r4y3 | Why in sand dunes is there no gravel or small pebbles? Only sand for miles? Wouldn't there be small pebbles at least? | Wind pushes the grains around. The heavy stuff doesnt move as well as the light stuff, so it gets left behind. The too light stuff gets blown away completely. What is left is sand, too heavy to fly away completely but light enough to move alot. | 7c392bed-54ae-40e4-a720-01c690630d5a |
c2ru69 | Why the laws of physics are unstable | You seem like a nice sort, and I honestly think you're very earnest.
So, hm. Most stories are just stories, you know?
On a grand cosmic scale, yeah sure there could be areas of the unobservable Universe where some physical laws are very different. And depending on what you believe about multiverse theory, there's sure to be some wild stuff in there.
But in the small scale, earthly scale, the laws of physics are very dependable. | ca82b159-b742-4765-bd43-cf372174d920 |
c2s64k | How can a computer beat a human at chess? No matter how pro a player is, a computer can always beat him. How? | Being a good strategist at chess basically hinges at how many iterations of the board you can predict.
If you're only thinking of the next move, playing against someone experienced you'll always lose basically because they're thinking five or ten moves ahead.
A computer program might, for example, be able to look thirty moves ahead. That means they can plan strategies a lot further in advance than you can, and can use that knowledge to steer you in the direction of a loss, basically. | cc24e657-b854-432f-bab6-20d758358313 |
c2s88j | - why do you get tired after crying? | Crying is usually due to some emotional stress, which is very exhausting. Your brain is one of the biggest energy burner. | 0dfb397b-13e5-41d8-a8ba-635941b45707 |
c2s9z2 | How do civilizations so distinct and distant from one another (like the native americans and the inhabitants of ancient China for example) shared the same technologies, such as the bow and arrow and the spear, being that there is no way of having a technological interchange between them? | All humans originally came from the same area in Africa, so any inventions from before we spread out would have stayed with people in different areas.
It could also be that they are simple things to make and they work well, so both civilizations could have invented them independently and decided to keep using them | e1b82ca1-f548-4c5f-8a86-d0b65b75bee8 |
c2sgj8 | Why if arms and legs are exposed to the sun for the same amount of time, do arms typically come out more tan/burnt? | The sun is above you. The first thing it hits is the arms. Your body and clothes provide an intermittent shield of shade to your legs. If you were to, say, sunbathe by laying on a lounge chair and don't move, your legs will tan equally as fast. In some cases, even faster than your arms since the arms have more sunburn preventing melatonin in them from more normal exposure. | 473d11e7-cfd3-4a04-a0fb-28292035ffc3 |
c2sgm5 | How do electric fences shock things if they are only touching one end of the wire, not allowing it to complete the circuit. | Electricity likes to flow to earth ground via the path of least resistance. The wires on electric fences are not insulated. When built, the electrical resistance of air is greater than simply continuing along the wire. When an object that also has contact with the ground touches an electric fence, the object is now the path of least resistance to earth ground, so the electricity flows through the contacting object to the ground. | cf057634-6a0b-46a7-8e5e-a0fb1655c8a0 |
c2suej | Why do crickets only "cricket" at night? | Crickets are found chirping, or cricketing at night because they are nocturnal and most active at night. They create that noise by rubbing different parts of their wings together. They stop when people or predators are nearby because they can sense vibration and they believe the best way to hide is to be completely silent. Only males chirp too btw because they are tryna get jiggy with the women crickets playing some sweet, romantic, and passionate heavy metal with their wings. The bitchets (female crickets) love that.
Edit: changed “jiggly” to “jiggy” | 6e65d178-3f27-456c-876f-cef4dd7c957c |
c2sw26 | Why do people not bleed constantly during surgery? | Smaller bloodvessels that are cut close themselves through blood coagulating but for bigger arteries surgeons have clamps that close the vessels to prevent a bleed out.
Thats is why its extremely important to tell a surgeon or dentist or who ever is going to cut you in anyway if you are taking any blood thining medication. Because if you are the bloodvessels won't be able to close themselves and even the smallest cut will bleed continously which quickly can become dangerous for the patient. My dad is a dentist and has had several instances where this has happened. | 11e6473e-1cb1-432f-b424-550b7e11bf10 |
c2t0b6 | How does a weighing machine work? | In general scales use springs with a known spring coefficient. This means that the designer knows how much force is required to extend a spring a certain distance. This distance can then simply be translated to a weight.
Digital and electronical scales usually use something called a "strain gauge". In general this is a material, say a piece of iron which when a force is applied to will deform. This deformation will affect its resistance and by running a current through and measuring the voltage or the current one can calculate what force has been applied which corresponds to a weight.
Edit: spelling. | 34f0e7de-0617-48ef-9fc3-06c9169138cb |
c2t0n2 | I've heard many times that honey is actually a superb home remedy for burns. How true is this, if at all? What's the science and chemistry behind it? | It's at most *maybe* true. There was a metastudy conducted in India on whether honey was useful for healing burns, and its findings were that honey can be effective for improving the healing of minor, surface burns; its effectiveness was not proven on deeper or more serious burns, however. Since there's only one study, and the results have not been repeated, it's difficult to say how accurate the results were.
The study did not explain why it may be effective, but honey does have mild antiseptic and anti-inflammatory properties which *may* help promote healing. | 558f2556-a218-4b83-9f56-53f1e34ae5c0 |
c2t2j6 | What makes warm-blooded creatures warm? | Cells in your body generate heat when they turn chemical energy into mechanical for example. When excercising your muscles take energy from food, sugars, and turn it into movement ie mechanical energy. When doing this there's also a loss of energy in the form of heat energy. So all your cells generate heat whether they be muscles or brain cells.
Cold blooded animals do the same but their cells don't generate as much heat. They instead rely on heating up via sunlight. Snakes are a good example of this.
Edit: spelling | 1667ac62-3a10-4755-8866-e39c1d4b0cc1 |
c2ticc | When you close your eyes, why do you sometimes see small, floating black spots? | It’s actually the vitreous humor (jelly-like material inside your eye) clumped together. More common when looking at bright lights and/or if you are near sighted. | 0b0966b0-2e2d-4273-a67b-03073313a45a |
c2twve | - Recently theres a huge protest regarding the anti-extradition bill in HK. It was stated “about 2 millions protesters” join the rally. How did they count the numbers of peoples? | They didn't. They made an estimation based on social media activity, density of people over a given space (as a sample), and total space the protests took place over. Of course density decreases with distance, but the models account for this.
So it's an educated guess. | ca7e865e-3aa4-4ff2-99c8-a8dfe9fe4fb1 |
c2u0k9 | Why do people find destroying things so enjoyable? | There is a tactile response when you break something that is known to reinforce that behavior. There is also a power dynamic that comes into play where you can impose your will on the object. | b4f8cae6-cca0-4bb5-8768-faa9dd151792 |
c2u1tz | How can radiation change our DNA? | The radiation itself doesn't actually change our DNA, it damages it. Radiation is very high energy, so it can ionise our DNA, i.e. it can knock electrons off our DNA thus breaking bonds holding it together. Our body tries to repair that damage, but sometimes does it badly or makes mistakes, and the result can be cancerous cells. | e78e4474-80a1-47df-a055-8113955a45b1 |
c2u8r4 | How do scientists explain the creation of the first single cell organism? Did it have parts like the mitochondria we know today? | Firstly, mitochondria only exist in eukaryotic cells, which make up multi-cellular organisms. Most single-celled organisms (prokaryotes) do not have mitochondria.
Prokaryotes are very simplistic in comparison to eukaryotes. They have no nucleus, and no cell membrane. The current theory is that pre-biotic molecules evolved, through natural selection, to become self-replicating. From there, the first single-celled organisms evolved. However, the exact origins are still poorly understood.
Interesting sidenote - mitochondria were once single celled organisms. They formed a symbiotic relationship with other single-celled organisms, to form eukaryotic cells.
*edit* for the avoidance of confusion - there *are* single celled organisms that are also eukaryotic, like protozoa. They're the exception rather than the rule. | e6bf19f6-8d21-4bb2-b42d-56b3fbb39705 |
c2uu21 | Why should China selling US treasury bonds have any effect on the US economy (question inside)? | If China were to sell off a lot of US bonds, the supply of bonds on the market would increase and people would be less likely to buy newly-issued bonds.
In order to make newly-issued bonds competitive again, the government would have to offer a higher interest rate, which means the government would take on more debt. | beaa08c8-d138-4bb1-8ffa-de1dcf9ee06b |
c2uvxn | How does the body of a pregnant woman decide when to give birth? (Water breaking, etc.) | Thinking back to uni biology about 20 years ago I believe that when baby is big enough, the baby will put pressure on the bottom on the uterus that triggers the release of Oxytocin. Oxytocin then triggers contractions and dilation. Next step is baby | 9bdc6075-32f1-4c06-bb6b-34e43edda598 |
c2v837 | How does changing a country's debt from the USD to its local currency benefit that country? | Other countries can't control the value of USD. If they have USD debt and the value of the dollar rises against their local currency, their debt gets bigger.
Many emerging markets are having this issue right now. They took out a bunch of USD loans in the aftermath of the 2008 crash, and now that debt is getting harder to service as the dollar gets stronger. | 4d1f4e68-cfab-487f-a906-e26c8bb456e3 |
c2v8mk | How come Vanilla Ice was sued for stealing a beat... but nowadays artists like Ariana Grande can do it freely? | They could have paid the artists or their estates for the right to use them, were as Vanilla Ice didn't get permission or even pay to use it. | 4a7cacf4-7bb4-4abf-88c7-296c77141dcb |
c2vc1g | How do filmmakers/artists make a bright/blinding white compared to a normal white? | Contrast. If a scene is largely dark, a bright spot will appear brighter than if that brightness were to fill the whole screen. Likewise if a scene is dark and then cuts to a completely white screen, our eyes will have to adjust to the change in brightness, and it will appear brighter than it actually is. | 065c580b-4442-4084-947f-f01c78487f26 |
c2vd8u | Why do blockbuster movies like Avatar and End Game have there success measured in terms of money made instead of tickets sold, wouldn’t that make it easier to compare to older movies without accounting for today’s dollar vs a dollar 30 years ago? | Industry news focus on money because studios want to make money off releasing the film. The amount of money made versus the amount of money spent on making and marketing the film is what people in the film sector are interested in. It's not supposed to be a scientific comparison, and not relevant for whether the movie is good of course. | a4ab8726-a438-448c-abfd-7b71befbfe9e |
c2vh8k | Why do seemingly non-perishable items — like rubbing alcohol, dental floss and body lotion — have expiration dates? | While there is actual chemical breakdown where certain items eventually do become less effective or physically break down (items from 1970 would likely not be very effective for instance), most of it's marketing designed to get people to toss stuff out and replace it.
It's even the same with foods: The 'best by' date has a grain of truth to it as far as when it begins to chemically alter and lose its desired taste, but is NOT the same thing as an 'expiration date,' something that only applies to certain food items (mostly baby products, dairy, etc). Very often canned and dried goods can survive much, much longer than people think and get tossed for no reason at all.
Don't take this as an invitation to eat random 30 year old tins of beans, mind you, since things can definitely go bad and in dangerous ways, but chances are you can ignore the date on dental floss or lotion. | 1439a78f-d7d8-43de-bf4f-17c44f1272a5 |
c2vibc | Why is it that Asians get the Asian blush? I understand it has something to do with an enzyme, but what is the trend between this issue with alcohol & Asians primarily ? | Basically when you metabolise alcohol, it is as with a lot of drugs broken down in the liver. You generally have 2 main enzymes for this. Alcohol dehydrogenase which breaks down the alcohol into acetylahyde, and then Acetylahyde dehydrogenase which breaks the products into vinegar like substances. Acetylahyde is toxic, in a nutshell, and produced by alcohol dehydrogenase. Asians generally speaking, have a more efficient enzyme, hence producing more acetylahyde, therefore this build up of toxic byproducts generally causes the flush. As for why it's common - supposedly it acted as a mechanism to ward off parasitic invaders. - most diseases that persist have had some historical role in keeping us from facing a worse fate. So for example, anorexia - it's lethal today - but it has been hypothesised that it made people move tribe to find a better location, as it usually gives energy, hence protected against famine... | c018e2ae-c859-48e0-a683-2e2d13f3f43e |
c2vk1j | How does the US Tax system work? | I’m not a CPA, but in a nutshell yes everyone who is employed gets taxes taken out automatically each paycheck however, sometimes they take too much or not enough because of the plethora of deductions individuals might be eligible to claim. Every year we must report any income and deductions we are eligible to claim to the IRS. Deductions reduce the amount of your income that is taxable. Some end up paying more and some get money back. | 03fddc7d-d05e-4cdc-9d2b-378bbf190467 |
c2vma8 | How do metal detectors only sense metal? | They're looking for materials that interact with a magnetic field. Out in nature, this is almost always a conductive metal.
There are other materials that react to or interfere with the magnetic field and could produce a false reading, but they're pretty rare.
You're unlikely to stumble across a deposit of magnetic ore or some kind of human-made conductive ceramic while checking the beach for jewelry. | 26e801f4-dd50-4a83-a1cf-39d3ea117ce6 |
c2vzt8 | Can the US ever leave the Middle East alone? | There is a large Jewish population in New York and other areas which can sometimes decide the Presidential race. In addition to this America is always concerned about oil supply from the Middle East. If America ever weans itself off oil they may become less involved in the Middle East. | 7389a1d6-8ab5-4412-92e0-7dc6084dd98e |
c2w4a1 | how is GDP calculated and why? | I'm a finance student fresh after economics exams so I can help you.
Y(gdp) = Consumption + Investment + Govt Spending + Net Exports (Exports - imports)
GDP due to the circular flow of money tells us about total income, expenditures or revenues in the economy (1 dollar spent by someone is 1 dollar earned by someone so they are equal).
GDP is a measure of all final products made each year in a given country and sold at market price. It is not the perfect indicator of wealth because you have two parameters: the price of products and the amount of them. If both price and quantities produced increase, you will not be able to accurately compare the GDP increase between two countries or two given years. A better index is Real GDP which works more or less the same but holds prices fixed (You assume one year to be the base year and during calculations you take the prices from this year). This way you can compare the increase resulting from the increase of quantities of produced goods. An even better index is Real GDP Per Capita, where you divide the GDP by the number of people living in a country. This way you know how much does every person have on average so you can better compare 2 countries which might have equal Real GDPs but different populations.
The GDP is imperfect also because it does not value things which don't have their market for like time spent with your family, the value of leisure etc, the value of clean environment etc. | e448dbf9-3a47-4177-b1a1-8047361cfd0c |
c2w8uc | Aristotle’s virtue ethics. What makes his theories important? | Which part? Its been a while, but from what I remember in order to be a good person we have to find the golden mean to our character. Not too cowardly, but not too reckless, finding the balanced 'courage' in between. So on and other similar stuff. Im sure someone who has studied this more recently can break it down further.
& #x200B;
[Here](_URL_0_) is a youtube video about Aristotle that is broken down pretty well. | 9c1acc9c-af61-4c15-9e10-2157e1aa6ba3 |
c2w9y5 | We close our eyelids when we sleep. How do we "close our ears"? | You don't. Your brain is listening all the time for any noises that might mean danger but apart from that it doesn't process them further while you're sleeping. Think of it as a kind of stand-by mode. | 2f9cce87-2943-4cc8-bd16-bfdffc900408 |
c2webb | What is a second mortgage for? | It's just another loan, with your house as the collateral. If you own your home, a lot of your wealth is the home itself, which means you can't use that wealth to pay for things. A 2nd mortgage converts some of that wealth from property into cash so you can spend that wealth. | 6ff3a8b5-974c-4684-82b3-fd807762b870 |
c2wic2 | Why doctors offices overbook then fall behind schedule consistently | Because there is a certain % of cancellations that can be measured over a large sample size. So if you are a doctor and you see that you have, let’s say, a 10% cancellation/no show rate then you will start to overbook by 10% so that you - as a physician - aren’t sitting around waiting.
Sometimes statistics don’t play out on a daily basis so on the days when everyone shows up, you end up being overbooked.
There is a decent amount of skill and finesse in scheduling and it sounds like that particular office isn’t very good at it - but it’s something every office does. | 514948b3-6713-4dac-b982-11d8f6fd061c |
c2wlm6 | What actually physically happens when hard drive "fails"? Does it just ''wear out''? | In a platter drive (the older, typically larger capacity ones), they have one or more thin discs of metal on a central spindle, and one or more arms with a sensor that act almost like a stylus on an old vinyl record player. When those drives fail, one of the following has typically happened:
- Physical failure of the central spindle
- Physical failure of the sensor arm
- Failure of the sensor
- Failure of the input/output socket or circuitry therein
On newer, solid state drives, it will be a problem with the chip or the board that the chip is mounted in. There are no moving parts. | 494f3e2a-7a34-487c-9ff7-23d51a5df4ee |
c2wo1m | why is it that sitting in a hot room feels horrible but taking a warm shower feels a lot better? | Because in a hot room you are typically clothed, and in a shower you are naked. If you sat in a hot room nude, it would be much more comfortable, but then everyone else at the office would be uncomfortable. | ed39d026-a3eb-4106-a554-bd48f5033150 |
c2woh8 | In an action film, the hero climbed on top of a fast moving train, then jumped forwards from one carriage to the next to get to the front of the train. Is it possible in real life, and whats the physics behind it? | Yes it's possible. The only thing making it difficult would be the rushing air pushing you back. | 4ecb6a3c-6015-452f-adfd-f0869791c353 |
c2wwhp | I'm encrypting a drive on my PC and the software I'm using instructed me to move my mouse as randomly as possible before it formatted for encryption. It says this "significantly increases" the encryption. How? | Computer are bad at making truly random numbers, because they're running code and code is, by definition, deterministic: it has to run in a certain way. We can make a sort-of-random algorithm (algorithm is just a fancy word for a piece of code) that takes an input (a seed) and then uses that to decide on different paths through the code.
For example I can ask the user to enter a word, and then use things like the length of the word, the letters of the alphabet used, the "difference" between the letters used etc to take different paths through the code. This makes a hard-to-predict result which looks random but actually isn't, because you'd get the same result if you used the same seed data. We call this "pseudo-random", which means "sort of random"
The trick, then, is to find good quality seed data. Good random number generators will basically find as many sources for this data as they can: for example you could use the current date and time (including milliseconds, since that changes a lot), or you can do things like look at the number of network errors you've had in the last hour since that's likely to include some actually-random line noise.
By combining a good pseudo-random algorithm and a good random-ish source of seed data, we can produce something pretty close to random. In most cases, this is sufficient.
If you're **really** paranoid, though, you can add in other sources of actual random data and either just use the output directly, or use the output as seed data for your algorithm. For example you could take some radioactive material and measure the decay and use that.
Obviously it's not easy to get hold of radioactive material, though, so most software will find something a little more accessible... humans are pretty random, so we can use one of those. Namely you. Now all the system needs to do is as you to do something that's hard to control precisely (move a mouse, for example) and that you will do for a reasonable length of time.
Moving a mouse for 30 seconds will mean that you have potentially hundreds of different movements with lots of different data: start and end points, travel time, travel distance, pauses between movement etc. It's pretty close to truly random.
By having you move your mouse a lot, we have easy access to a pretty random source of seed data that will be almost impossible to reproduce | a596bf0f-62d0-4958-851f-4bc6648afbce |
c2wz93 | How can artists release music after they have passed away? | 2 things. The recording and releasing process takes time. A recording may happen one day, but then many months could go by in producing the rest of the song. Tweaking the background music, changing the volume levels here and there, etc. So it could be possible for someone to record an entire album die, and then the remaining music production happens before the release. The other way is that if the artist recorded a song but didn't quite like it enough to include it on an album, or wanted to make some changes to it before they released it. After they pass away, their family may choose to release the "unfinished" songs. | f42d0087-b01a-47d6-b81f-e02d3720c658 |
c2wzca | How do county and city police departments decide who responds to what call when they have overlapping jurisdictions? | If it's inside the city limits the the city cops take care of it. If it's outside the city limits but inside the county then the sheriff's department takes care of it.
There can be exceptions, for example the county jail is run by the sheriff even if it's in the city limits. | 814722eb-16bb-4554-b241-08a5b267a3c2 |
c2x07d | DC splitter question | Probably not, 1.5A is not enough for 4 hard drives. Most HDD's draw 6-9 watts (0.5 - 0.75 amps @ 12v). At most, I would put 2 on one power supply. Too much load on a PSU can cause a voltage drop and that can cause the HDD's to malfunction.
& #x200B;
Also, this is more of a /r/techsupport post. | dbbba5fa-e550-4b65-a721-9d565904f343 |
c2xd4i | I've seen many articles that claim that our genetic information is the most personal information we have, and that by having our DNA/genealogy tested, we are selling this information to third parties. But why is that a problem? What can companies and organisations actually *do* with your DNA? | The most concerning case (and by far the most likely) is that these gene sequencing companies will sell your genetic code to insurance companies, who will use that code to increase your premiums or deny coverage.
It isn't inconceivable that your insurance provider would look at your DNA and see that you have a gene marker for a type of cancer, then raise your rates because you are an "increased risk" based on that marker. Even worse, they might start claiming that the cancer is a "preexisting condition" due to the marker and refuse to pay **at all**.
Most people feel that is an incredible invasion of privacy and very unfair, so they suggest not allowing insurance companies the potential option. | fd0724f6-b47c-4699-aa4f-f24d3312e088 |
c2xgsw | Why do administrators try to deny a disaster is happening when a disaster is truly happening (better explanation to my question in desc.)? | In the specific instance of Chernobyl, they didn't believe it was possible for the reactor to explode. Too many fail-safe mechanisms were in place for that to possibly happen. It just so happened that one of those fail-safes was flawed. They knew it was flawed before hand, and didn't address the problem. Russia is a very prideful group of people. They didn't want to admit that a disaster of that scale could have happened on their watch. No country wants to admit that something they did is going to have a negative global impact.
For other instances, there are several reasons. Reducing panic in the public, mitigating negative publicity (no one wants to be at fault), saving-face, etc. | 466c84f7-0320-4d17-bfa8-16115678707e |
c2xop9 | When a car is stationary, where does the engine’s power go? | That is where a clutch comes into play.
When you are idle the flywheel disengages from the clutch plate and stops the engine from transferring power to the drive train. When you start moving again, the clutch and flywheel press together and power is transferred back to the drive train.
There is some slippage there. That is how a clutch gets worn out. It is rubbing against the flywheel. | 1424ac2c-b73c-4bd3-abf3-0b5d72a11e66 |
c2xwe2 | Why is it so much easier for me to pull flexion muscles of my toes compared to those of my fingers? | I'm not sure what you mean here. If you make a fist, you are flexing your fingers, which is pretty easy for most humans to do. | cd0b1363-9cb7-4914-b7f6-ee77ae0c0af8 |
c2yikp | Why some materials can/cannot scratch other materials | It is a property of the material called hardness. Higher hardness always wins the battle.
What determines hardness is the strength of the molecular bonds of the material. | 0f6e86c9-9558-4e5c-aa35-0f4a7f694402 |
c2yn8k | Is economics a science? | It's considered a social science, like political science, sociology, psychology but not a natural science like chemistry or physics. Social sciences don't have hard and fast rules that are replicable, because you can't isolate experiments in the real world like you can in science labs. | f9461325-0a6a-4852-972f-d79e31101620 |
c2z27b | When a company offers a direct listing for a new stock, how is the initial price point determined? | In the case of a direct listing, the original share holders put up their shares and determine the value themselves (no underwriters involved). It is much cheaper for the company but it is also considered extremely unsafe. There are no protections against the price swinging violently.
This can lead to your shares not being purchased; low demand = no value and your stock tanks.
Doing an IPO comes with the backing of security. In certain cases, where your product/offerings have an extremely solid future, or an already established market presence, you can do a direct listing and basically pop bottles because your product is the tits. | bcf728d4-77db-4396-b96d-6d55b3c72f06 |
c2z7dx | Why do animals such as deer, squirrels, raccoons etc. sometimes cross the road right as a car passes? Why don’t they wait for the car to pass? | It’s one of those “If a tree falls in a forest and no one is around to hear it, does it make a sound?"
There’s no doubt animals could be crossing the road at any time, all the time. But you’re only noticing those that you drive past. It’s coincidence. | 376f6412-6022-45b4-a41e-eba9a7091137 |
c2z89k | How does alcohol dry things out? | Alcohol and water are miscible (they can mix). If you place electronics in alcohol, it will reach all the tiny corners where water is hiding and mix with it, “diluting” the water.
Then the alcohol evaporates, so the remaining water is now spread out over such a large volume that it evaporates quickly as well.
The detection strips rely on a hydration reaction with water. They probably won’t work with alcohol. | d21154b9-ea0a-4a6e-af4f-5d25c974774e |
c2z90i | What does it mean to write something off for tax purposes? Is it worth it? | Depends on your country, you tax law, your state (as in self employed or employee, or owner of a enterprise..), your situation, your income....
In short. Everything fictional here. Just simple numbers to make it easier
Say you are self-employed. You bill a 1000 dollar. You pay 30% taxes. You take home 700 dollars. You then buy an office chair of 100 dollar.
You have 600 dollar and an office chair.
You now write off the chair from your taxes. It's a 100% business expense? You now have spent 100 dollar before taxes. So your income is now 900 dollar, taxed at 30% (the chair is deducted from your income)
You now have a tax write off on your chair, and 630 dollar after taxes.
You just made 30 dollar back. | 2dfaa459-7d85-45fb-abab-7995c4e2181b |
c2ze5o | In the news I'm seeing that Iran shot down a US drone. My question is: would the US allow a drone from Iran to freely fly around the US or shoot it down as well? Or was it part of an agreement that the US can fly whatever they want in Iran? | It’s claimed by the United States that the drone was in international air space and Iran shooting it down was an act of aggression.
My thing is: it’s an unmanned drone!
It’s not anything to raise hostilities between Iran and the US. | df4abd99-4a0e-4017-9c46-1f6303f52d45 |
c2zetp | What happens in species that can hibernate which prevents musculature atrophy? | They do experience muscular atrophy but in those animals which have evolved to hibernate, their brain basically twitches the muscles while they sleep to maintain the strength. It's an involuntary muscle action, same as you don't stop breathing and your heart doesn't stop beating while you're asleep. | e81b7e9d-6884-48ce-b95d-df2acf8c3ad5 |
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