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l3ppdl
|
Why do birds getting sucked into a jet engine cause such trouble? The engine can lift a jet, so how is it not powerful enough to chew up some bird bones with no problem?
|
Other
|
explainlikeimfive
|
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"Jets are extremely sophisticated machines. It can chew up bird bones, but not without clogging the very fine tolerances and air path needed for compression and the production of thrust. Not to mention turbine blades are not meant for cutting, especially at the extremely high speeds that they will hit birds. I work in aviation repair and have seen the nicks and dents created in them. Every little imperfection is a loss of efficiency, so a big deformation on multiple blades might be enough to kill the jet's power entirely.",
"The same power that makes it chew a bird with ease also chews another turbine blade with ease - which can cause a cascade of failures as lose pieces of metal start chewing into each other at incredible speeds.",
"They are designed to chew up birds and not malfunction, you can watch engine test videos on YouTube. The problem is that usually an airplane suffers a bird strike on takeoff and if it’s enough birds it can cause a flameout in the engine causing it to lose power."
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l3qy7t
|
Why is it safe for MMA fighter to wear such minimal gloves but boxers such larger ones?
|
Is this simply a case of the regulatory bodies involved in each sport?
|
Other
|
explainlikeimfive
|
{
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"Ironicaly, the advent of gloves made boxing more dangerous. See, hands are delicate structures, easy to injure and break. That means you have to be careful how hard you punch and where you punch. Headshots were rare pre-glove, because the skull is hard. Bodyblows, like to the kidneys or stomach, were more common Add padding in the form of boxing gloves, however, and you can throw full-power haymakers to your opponent's head all day.",
"MMA is mixed martial arts meaning striking isnt the only way for an opponent to be defeated. Imagine trying to clinch with someone and get a good grip on their arms for an arm bar with boxing gloves. Edit: not necessarily safer, just more practical.",
"Its isnt \"safer\" but it is necessary because mma fighters need to grapple and grab alot for takedowns or submissions. Boxers dont. Imagine trying to grapple and do juijitsu with boxing gloves."
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6
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l3rmef
|
Why is the skin on your face prone to blackheads and pimples so much more than the rest of your body?
|
Biology
|
explainlikeimfive
|
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"The sebaceous gland produces sebum, which is an oily substance that moisturizes and protects the skin. Excess sebum production can block the sebaceous gland duct causing a comedo (a clogged hair follicle or pore), commonly known as a blackhead or whitehead. Unchecked a comedo can lead to an infection — acne. In humans, sebaceous glands occur in the greatest number on the face and scalp, but also the shoulders, upper chest, and back.",
"Human skin has pores that connect to oil glands under the skin. Follicles connect the glands to the pores. Follicles are small sacs that produce and secrete liquid. The glands produce an oily liquid called sebum. Sebum carries dead skin cells through the follicles to the surface of the skin. A small hair grows through the follicle out of the skin. Pimples grow when these follicles get blocked, and oil builds up under the skin. It is unclear what role diet plays in worsening acne. Scientists have found that people who consume a diet that offers a good supply of vitamins A and E and of zinc may have a lower risk of severe acne. One review describes the link between acne and diet as “controversial,” but suggests that a diet with a low glycemic load may help. These are the top 10 pimple treatments in the market right now: URL_0"
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l3s8z9
|
Why can't temperatures in the universe be infinitely hot or infinitely cold?
|
Physics
|
explainlikeimfive
|
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"If you think of temperature as the average kinetic energy of the atoms, it makes sense: you can not have less kinetic energy than something that is absolutely still. When the atoms in an object are absolutely still, the temperature is absolute zero. Conversely, infinite temperature means infinite kinetic energy, and there is not infinite energy in the universe. Energy can neither be created nor destroyed (only converted into our from other types of energy).",
"Temperature is a function of energy, so an infinitely hot temperature would need infinite energy and an infinitely cold temperature would be the complete absence of energy. The universe has finite matter and energy, so the first temperature is impossible, and the second cannot happen naturally because particles are always going to have some small bit of energy. We have methods to remove a lot of the heat, but to reach absolute zero would require an [infinite amount of energy]( URL_0 ) to fuel those processes, which is again impossible in our finite universe.",
"Temperature is the measure of how much the molecules in a substance are moving - vibrating. At absolute zero, they are not moving at all. How can you be moving less than not moving? Infinitely hot would take infinite energy. So while mathematically it is possible, it does not make much sense pragmatically.",
"Temperature is defined as average molecular movement. So at a certain temp (absolute zero) the average molecular movement is 0 so the molecules are stationary. You can't be anymore stationary than stationary, so they're just fixed in place, although there is some really interesting physics at and around this temp. At the highest temps humans have achieved matter tends to break down and weird physics stuff happens that's way over my pay grade and involves string theory. But the gist of it is that matter likely has an upper limit of how quickly it can move before it is simultaneously occupying both states of existence at once (ie it's moving so fast it's effectively in two places at once).",
"\"Infinitely cold\" is just [absolute zero degrees]( URL_0 ). It's impossible to make anything that temperature because the universe around it will leak in some heat, and there's no real way to pull away heat all the way down to zero. We've gotten REAAAAAAL close though. \"Infinitely hot\" would be a black hole. Stuff enough energy into something and it'll phase-change, but you can keep pumping in more energy. Up until it becomes a black hole. ...and you can still throw more stuff in it. I'm not sure bigger black holes are considered \"hotter\". I guess they are. Infinity is just a hard target to reach. Even if you threw in all the mass in the universe, it could still take in more. Probably."
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|
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l3scsc
|
Why couldn't they mix purple dyes in ancient times?
|
Purple dyes were very rare and valuable in ancient times because they could only be laboriously sourced from a particular type of shellfish. But blue dyes and red dyes were available comparatively widely. Why weren't they able to create purple by combining the red and blue dyes?
|
Chemistry
|
explainlikeimfive
|
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"It has long been possible, as you say, to get a purple shade by combining a red and a blue pigment. But adding a new pigment to a mixture always serves to take more of the other light away, not add more of the desired colour of light. So, even the purest, most vivid and saturated red pigment found in nature, and the purest blue pigment, would only give you, at best, a [muddy and darkish shade]( URL_0 ) of purple. The vivid violets and purples you see in flowers and on [birds]( URL_1 ), couldn't be rendered this way. If you want vivid purple paint but yours is too dark, there's not much you can do to save it. You can lighten it by adding white, but that just makes it more grey, not more purple. In general, a mixture of two different pigments will always produce a colour less saturated than the components you started with.",
"URL_0 > There are two ways to mix colors, additively, and subtractively. When you mix dyes, you get the subtractive kind of color mixing. Under this method, when you mix red and blue you get black or brown, not purple. > It is under additive mixing, like when you shine different colors of spotlight onto the same piece of stage, or when you have a TV or phone screen giving off different colors in different pixels very near each other, where red and blue make purple.",
"Its a myth. Okay, it's not a myth. But it's massively misunderstood. What you're talking about is a specific shade of \"purple\" called tyrian purple. It was also called Phoenician red because it didn't actually look very purple. The reason it was so valuable wasn't because it was *purple*, its because it didn't fade. So, normally clothes fade with washing. I mean, even our modern clothes do so you can be certain it was worse in ancient wherever. Most dyes faded over time, becoming dull and washed out. But tryian purple became brighter and more vibrant with wear. Instead of looking older and more worn, the colour would become better over time. Combined with the how hard it was to produce (its crazy complicated and required thousands of one specific type of sea snail), it was crazy expensive and quickly became asociated with royalty and the upper classes. As for mixing, there are are two things to keep in mind. First is that they didn't have true colours; they had ground of plants and animal goo and rocks. What colour do you get when you mix ox blood red with turquoise blue? It's probably not purple, even though you're mixing \"red\" and \"blue\". Second, they werent dying paper white fabric. They were dying natural, home spun cloth. So at best it was probably cream or slightly yellow or light tan. Bleaching fabric wasn't really a thing in Europe until the 16th or 17th century. And the methods they had to bleach it - lye - probably isn't very quick or kind to the longevity of your fabric."
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4,
4
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l3suaa
|
What does it mean when an object is irradiated?
|
Does this object now also give off radiation/become radioactive? For example, if a dust particle were to be hit by a ton of gamma radiation, would this piece of dust become radioactive? Edit: what does it mean when the piece of dust becomes contaminated?
|
Physics
|
explainlikeimfive
|
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"Radtech here, a material is either radioactive or not, and can be made radioactive through intense neutron bombardment to change the overall atomic structure to create an isotope. If a material inherently gives off radiation then it is radioactive, if it is covered by a material that is radioactive then it is contaminated, if it has received a dosage of radiation then it has been irradiated. If you have received enough neutron radiation to become radioactive then you're going to have a baaaaad time. I've seen what a cobalt-60 source will do to a person... eurgh i'd hate to see neutron.",
"Well, technically \"irradiated\" can just mean you've shone a bright light on an object. Assuming you're talking about ionising radiation (e.g. the stuff that can kill you), AFAIK the only way that can make a material permanently radioactive is via a process called neutron absorption, where the atoms of the material take extra neutrons in and get turned into (likely radioactive) isotopes. Gamma radiation can't do that.",
"Irradiation just means that something has been hit by radiation. Could be photons, like uv radiation, could be neutron radiation from a nuke. What happens after depends on what the type of radiation is, as well as the quantity. What you seem to be referencing is irradiation in the context of something becoming radioactive after being irradiated. This is something that just gamma rays won't do. Gamma rays will destroy lots of things, especially living organisms dna, but even huge quantities of gamma radiation will just turn that dust into plasma. After the gamma rays are removed you don't get any nuclear radiation from the dust. Though it will be quite warm. In fact gamma rays are used like this to sterilize things after being sealed like bandaids, and medical needles. For something to become radioactive you would have to hit it with neutron radiation. The neutrons hit other atoms and combine to form new nuclei that are usually unstable. These unstable nuclei will then decay into more stable nuclei after some amount of time, releasing energy in the process."
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l3temz
|
Why can't we just read the secret ingredients of coca-cola off the ingredient label on the back of the can ? What's secret about it ?
|
Technology
|
explainlikeimfive
|
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"The process in which you make things can drastically change the results. Their “secret” ingredient could be something special they add to the process that isn’t necessarily an ingredient. This is more a chemistry aspect then an ingredient aspect. Temperature, speed, time and a ton of other things can affect this, I can’t guarantee this is the reason why but it’s a possibility.",
"One of the ingredients is \"natural flavors\" which could be any combination of barks, spices, roots, fermentation products, buds, vegetables, fruits, or yeasts.",
"If you look at the recipes for Coke (and Pepsi) 'do it yourself' plans you will see that the flavor comes from a pretty complex mix of quite a few flavor ingredients. Even if they published what they were trying to get the precise combination in the precise amounts would be very difficult.",
"I will only give you 65kg of Oxygen, 18kg of Carbon, 10kg of Hydrogen, 3kg of Nitrogen and 4kg of ‘other stuff’. Now that you have all the ingredients, make a human.",
"I had a friend in sweet beverage industry. What he told me is that recepy for Coca-Cola is not a mystery for the last 20-30 years. It was reversed long time ago, however noone wants to face Coca-Cola law team. There are laboratories all around world specialized for \"taste\" formulas for food industry - they make industrial formulas for samples you deliver."
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3
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l3uego
|
Why does cheese taste salty while having almost no sodium?
|
When I eat avocado toast, I put a lot of salt on it and it really brings out a salty flavor. When I eat a cream cheese bagel, it already has that same salty flavor even though the cream cheese I used doesn't contain almost any salt. Why is that?
|
Chemistry
|
explainlikeimfive
|
{
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"Do you know the brand of cream cheese? Low sodium doesn't necessarily mean low salt. Potassium salts taste salty without the Sodium and is pretty common as a substitute. So it's likely there's either this, or something else being used as a salt substitute.",
"The bagel is salted too. And I bet it's way saltier than you might expect. Generally, bread dough is like 2-3% salt by weight - not uncommon to dump in salt by the tablespoon. Even though most of probably don't eat bread and think \"salty\". I would assume bagels to be in the same neighbourhood. Off the top of my head, I'd guess the bagel would be 15-20% of your daily recommended sodium because it's probably equivalent to, like, 2 slices of bread.",
"Some cheeses might contain other compounds, like glutamate, that activate umami taste receptors. Umami is sometimes considered “tasty” or salty in some way."
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l3v1mz
|
why do muscles and joints ache or get stiff with age?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"As for joints: Bones are really hard so if two bones in a joint would touch each other while moving, they would 'scratch' and cause damage. To prevent this, our body puts a softer, protecting layer between two 'touching' bones. This layer is called cartilage. Cartilage is really great but it does accumulate damage over the years and unfortunately it's unable to repair itself. (Because there are no blood vessels going through it). So older people usually have damaged cartilage in joints that have been used a lot over the years, causing pain.",
"Your connective tissue gets stiff due to changes in aging - cartilage becomes thinner and there is less of the lubricating fluids between the joints. Bones change as you get older - as you become more inactive the bones loose mass. Hormonal changes can accelerate this. Given that joints are moving parts this becomes a vicious cycle- the joints rub together with less protection making movement hurt. Since movement hurts you're less active - that causes your body to rob the bones of mass and that causes your joints to get stiffer. Since these changes happen later on in life, when most humans are past their child-bearing ages, we can't \"breed\" these changes out."
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5
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l3vhto
|
Why does hot water sometimes start to feel cold?
|
Had a shower earlier and i had to keep checking whether my water was turning hot or cold.
|
Biology
|
explainlikeimfive
|
{
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"text": [
"Its called paradoxical cold! So, your skin has hot nerves, cold nerves, and pain nerves. When something warm touches your skin, it stimulates those hot nerves and tells your brain that it's touching an increase in temperature. Touching a cool thing stimulates cold. Touching a pointy dagger stimulates ouch. But it's possible to overstimulate those nerves, which is what paradoxical cold is. The water isn't just warm or hot, it's burning hot. Your nerves kind of freak out and everything gets stimulated. The same effect happens with cold in both directions. First, if you've ever held an ice cube in your closed fist you know it goes from \"this is very cold\" to \"ouch\" pretty quickly. Second, when people are dying of hypothermia (when they're freezing to death), they often take off their clothing. Its called paradoxical stripping. Its not super well understood bc, ya know, prob unethical to freeze humans to the point of death just to study them. But the prevailing hypothesis is that its delirium, which prevents people from thinking rationally, combined with those hot nerves being stimulated inappropriately. Ie, people freezing to death suddenly feel like theyre burning up, so they start removing their clothing to cool down."
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7
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l3vqh7
|
How do mood rings transition from color to color?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Mood rings contain a liquid crystal that basically works similarly to a thermometer. Or in other words, the liquid crystals reflect different wavelengths of light at different temperatures.",
"Body temperature. I realized this by wearing mine while wetting my hands, cooler water made it turn lighter colors, and warmer water scorched it and now my ring doesn't work anymore."
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3
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l3w695
|
Rule of nines?
|
This is something I have been very interested in for a long time and have never found an answer to. If you multiply 9 at any number and then add the digits it will always come back to nine. I.E. 9 X 2 = 18 1+ 8 = 9. Nine is the only number I have found is the only number that does this. Any ideas why?
|
Mathematics
|
explainlikeimfive
|
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"Because it is one less than 10. To add 9 and 9, you borrow one. Now 9 and 10 are being added. You gained 1 in the tens place and lost 1 in the ones place. Repeat every time. Borrow 1, gain 1. To be more baffled, look at the rule of 3. Any number where the digits all add up to a number divisible by 3, is itself divisible by 3. So, 163947261 is divisible by 3, I typed that randomly, then added a 1 at the end to make sure it met the rule of 3. I haven’t checked, but I know it will work out.",
"It's actually something that transfers across bases as well. Base 8? Multiplying by 7 will do the same thing (all digits add up to a multiple of 7). Why does this work? Because as stated, 9 is one less than 10. Specifically, check this out: x * 9 = x * (10 - 1) = (10 * x) - (1 * x) = (10 * (x - 1 + 1)) - (1 * x) = (10 * (x - 1) + 10) - x = (10 * (x - 1)) + (10 - x) This may seem a little silly to see it represented this way, but that this show is that for single digits, you're putting one number lower in the 10's place, and putting the missing part to reach 10 in the 1's place. So for 8, 7 would go in the 10's place, and 2 goes in the 1's place. Regardless if what single digit value you pick, you'll end up totaling to 9. But what about when you have more digits? Well, let's pick it apart. What does it mean to have more than one digit? * Each digit actually represents that digit multiplied by however many 10's over it is So, if we're looking at a number like 357, that's actually 300 + 50 + 7. Since 9 * 357 is the same as 9 * 300 + 9 * 50 + 9 * 7, we can already tell that each of those products individually have to have their digits sum up to 9. ... but what about when they're added together? What happens? Well, let's take a look at what happens with addition, and how things look in relation to our decimal system... let's take this addition: 57 + 64 ---- 121 But how did that happen? The secret is in how we carry numbers over. 7 + 4 is 11, but we carry over the 10 over to the next column. Remember that we're focused on whether the sum of the digits corresponds to whether it's divisible by 9, right? Well, that 10 that's being carried over is turning into a 1 for the next column. **Both have the same remainder when dividing by 9**. That's the critical point. Because the remainder for 8, or 80, or even 800 will always be 8 when you try to divide by 9, it doesn't matter where in the columns that number is actually added if all you're checking for is divisibility. Just for a sanity check though... why is this? Well, let's break that apart: x * 10 = x * (9 + 1) = (x * 9) + x We know (x * 9) will be divisible by 9, so the remainder when we divide (x * 10) by 9 will always result in x. & nbsp; *WHEW!!* So we've got this far. What does all this mean? * Multiplying single digits by 9 will always result in the sum of the digits totaling to 9 * Multiplying any number by 10 will always result in the same remainder when dividing by 9 * Adding numbers together will result in the sum maintaining the same divisibility by 9 With all of that, we can now definitively say that any number multiplied by 9 will have its digits sum up to a multiple of 9! & nbsp; But wait... what about the other way around? How do we know whether if the sum of the digits is 9, if the number itself is divisible by 9? Well, it works in reverse. If you break down something like 357 into each digit like we did before (300 + 50 + 7), we know that for dealing with their remainders when dividing by 9, it doesn't matter how many times we've multiplied by 10. So, 357/9 will have the exact same remainder as (3+5+7)/9. That means if the remainder is 0 (i.e. you get a multiple of 9 from the sum), that must mean that the original number is also a multiple of 9! & nbsp; As a bonus, because the sum of the digits gives the same remainder as the number itself, if you end up adding all the digits and you still have a big number, you can add *those* digits together and keep going until you get your result! So for example... 529847382848247 gives you 81, which would then give you 9, so it's divisible by 9!"
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l3wfgb
|
What is so bad about the waste of nuclear power plants? Why are many governments so against it? What is so hard about storing the waste in a safe place?
|
Technology
|
explainlikeimfive
|
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"I'm a nuclear engineer. Elements can have different weights when they have different numbers of neutrons in their nucleus. A reactor is a neutron throwing machine. Certain atoms split into pieces when it absorbs a neutron, making smaller atoms, while others hold onto the neutron and get bigger. Generally, more neutrons make the atom radioactive, meaning it spits out energy and/or parts of the atom to be more stable, like a ball rolling down a hill. So, after running for 3-4 years, nuclear fuel has made some of every element in different weights. That includes toxic metals, which makes it chemically toxic, and many radioactive versions of atoms. People have long been conditioned to be afraid of radiation, though compared with most industrial hazards it is pretty easy to manage. In fact, the atoms that decay slowly (\"they last for hundreds of thousands of years\") release radiation slowly, and is of little risk. The real problem ones last a hundred to two hundred years, which is relatively easy to store. The short answer is fear and lack of perspective. Basically, reactors make a chemical soup that is capable of putting out a lot of energy for a couple hundred years, and after that you're left with a weird mix of elements. We have multiple techniques for reusing, recycling, and safely storing the used fuel, but fear keeps hitting those ideas down and we're left in a weird limbo as an industry. Essentially, a technically challenging but solved problem is being confused with the politically challenging and unsolved problem.",
"The waste from current nuclear power plants is highly radioactive and also toxic. It is stored on site under a pool of water until the worst of the radioactive isotopes have decayed but some of the particles will have half lives in the thousands to hundreds of thousands of years. This means the waste remains dangerous for thousands of years. Finding a place which is safe to store it is difficult, convincing locals to let you build that storage is even more difficult and then you have the cost of actually building long term storage.",
"Old reactors worked this way, definitely - they made spent fuel that is hard to safely store. Modern reactors don't. Heck, some modern reactors can use old-school spent fuel as secondary fissile (fuel) material! And then the waste they produce is pretty inert (harmless), edit: at least the waste we don't recycle, I should say! In short, nuclear science had come a long way, and modern reactor waste is not remotely as dangerous as old-school spent fuel.",
"Not here to argue. But I would like to share [this article here]( URL_0 ) Just scroll down to read the radioactive waste from a coal plant, and compare it to a nuclear plant. That said? Green all the way. Nuclear would be a *great* step away from coal though to help bridge the gap as far as carbon emissions go however. The article I'm sharing though is just to illuminate *how insanely bad coal is* compared to literally the most though of radioactive producer that actually isnt. Nuclear power just concentrates it incredibly. Now, compare coal to green, and ask yourself why people still argue for coal....",
"Nuclear waste is radioactive and harmful to people. Bad particles come out of it and if they hit you, they can really hurt your body. Because of this, many people are scared of it. And it’s right to be scared of nuclear waste, it’s dangerous. Thankfully, scientists have have worked really hard to make new technology so that the waste isn’t as dangerous. Nuclear reactors are more efficient now and we have storage containers that can stop the bad particles from getting out. The waste is still dangerous though, so we have to be really careful.",
"What really needs to happen: refine it, reuse it. This is possible and would save loads of money and prevent further spent fuel needing to be stored. This is completely possible and done in some countries-France for example, and should be an environmental priority.",
"There's been serious talk about having absolutely huge sites deep under ground near bedrock and have different types of signs that will be understood by people 100.000 years from now. That no treasure or valuables are buried here. Only death that will get worse the closer you get to it. And possibly even make a sort of religion around it to pass the knowledge to future generations.",
"Nuclear waste stays radioactive for a REALLY long time. During the first hundred years this presents little or no problems. BUT, after a while the drums sealed in concrete can and will begin to leak. Any leakage not only contaminates the the outer container but any surface the containers are in or on. That means you have to dig up the floor or dirt in the facility and recontain it and the original containers. This isn't a big deal in the short term but over hundreds and hundreds of years it's going to be a big problem! If 1 tom of waste is produced in the first years and each year there after: Year one = 1 ton of waste. Year two= 1 ton plus one ton equals 2 tons, Year three= 1 ton plus two tons, plus 2 tons, year four = 1 ton plus 3 tons equals four tons of stored waste. Still not a big deal, eh? Okay, lets say an accident occurs on year 8 and 44 tons of contaminated waste needs to be stored. Suddenly you have 54 tons of store waste!. Now, repeat this cycle every 20 years and by year 100 you have hundreds of tons of radioactive waste to watch over, contain and monitor. If an earthquake hits and damages the storage site you could have thousands of tens of thousands of tons of radioactive waste to contend with. Politicians can safely say \"they\" have nothing to worry about whole ignoring the radioactive legacy they leave for our descents to live with. Edit. These numbers are not consistent over the years and may decrease or increase depending om many factors. I was simply illustrating the concept.",
"Where do you think the nuclear fuel comes from? It's mined from the ground. The ground is radioactive. Coincidentally, but unrelated, the sky is too. Bananas are radioactive. So are people. You are radioactive. (Go ahead and google something like \"How Much Radiation Does the Human Body Emit?\" if you're curious.) It's totally natural and nothing to be concerned about. The problem with nuclear waste is just that it's concentrated. It just so happens that it's easy to concentrate, and that's what we do to get power out of it. You have to concentrate it for that. If you concentrate any dangerous thing (like a poison), then it's not easy to dispose of safely. One accident with a concentrated poison could get into the groundwater and contaminate the drinking water for an entire region. And that's exactly the fear of nuclear waste. Radiation isn't dangerous in natural amounts (well, it is, but no more so than just being in nature), but concentrated it can be much more dangerous. And we have to concentrate it to get that value out of it. The other aspect is how long can it be safely stored? It can take a long time for radioactivity to degrade. And we're a \"buy a new phone every two years\" society. We're not really good at long-term projects that can be secure for multiple generations. There's nothing technically stopping us, but human nature and our culture tends to ignore and neglect things that are old. We're fully capable of containing it safely, but not quite mature enough to do so.",
"Several items we call waste. First off the fuel which is highly radioactive is placed in dry cask containers, welded shut and filled with helium as a heat transfer medium. Casks are placed outside to continue to decay and you can walk right up to them. This is done all over the world. In the US there was discussion to consolidate the containers but currently the casks are stored on site. This is not hard and has been done for twenty years here in the US. Second by product is contaminated waste which includes old components, consumables for service work. These get packaged up and sent to a burial site where they are sorted. Some of the old components are stored on site as they are too large to move so utilities make a bunker and let the part cool off radiologically. All of the waste is monitored and disposed of safely and correctly with very few exceptions. The largest risk of nuclear is not really the waste. It is the potential for a large scale issue like Fukushima which could impact the area.",
"unrational fear of the people, and government workers are generally directly or indirectly elected by the people. Older people know of chernobyl and younger people learned of it, and then saw fukushima, even though they are not related in the slightest. They also see the direct deaths of chernobyl and not the indirect deaths of coal miners, oil harvesting and all the other side affects of dirty power. So people are afraid, thus government has to act afraid, even though it would be better and much much safer. Waste is not an issue, the world has thousands of sites we could easily store waste, and the waste created is very small amount.",
"> What is so bad about the waste of nuclear power plants? It doesn't take much place, but it's dangerous for a long time. Like 100,000 years. > What is so hard about storing the waste in a safe place? It's easy to store it for a short time, but harder to store it for a long time because in 100,000 years languages change, culture changes, even ground changes. You need to keep it in a very stable place like some mountains. > Why are many governments so against it? People are afraid of anything related to radiation. > Unasked question: [can we shoot it into the sun/a black hole?]( URL_0 ) It's hard and expensive. It takes *a lot* of energy to shoot things into the sun. And if the rocket explodes or falls down to earth, the dangerous waste is spilled all around. > Unasked question: is storage the only option? No. The \"waste\" is mostly good fuel, just with some dangerous isotopes in it. [Fast-neutron reactors]( URL_3 ) can use this waste as fuel and produce energy plus much less problematic waste which only needs to be stored for about 300 years. That's much easier. Nuclear waste can also be made less problematic in a process named \"[transmutation]( URL_2 )\". This is expensive though and doesn't produce energy to pay for itself. See also: [List of radioactive waste treatment technologies]( URL_1 ) on Wikipedia.",
"The waste is not that difficult to manage. It is small and easily stored. The problem is that it has a half-life measured in tens of thousands of years in some cases. So where do we put it that will be safe for that long? The benefits of nuclear also relate to the waste. Nuclear waste is small and easily stored, easily sequestered, unlike the waste of fossil fuels, which we puke into the atmosphere and which will take billions of years to clean up. (Life on earth has been sequestering carbon from the atmosphere for 2 billion years. We are putting it back into the atmosphere in a few hundred years). The resistance to nuclear power is an exercise in what-about-ism. Nuclear is cleaner, safer and cheaper than fossil fuels, and more practical than wind or solar for now. It is not perfect, and it will be overtaken by solar. It is marketed as an alternative to coal, not solar power.",
"URL_0 This is a brilliant and very short (6 minutes) video that EVERYBODY should see. The worst thing about spent fuel is peoples perception. In fact, it is the best kind of \"waste\", it is of low volume and has a half-life. It also has lots of energy left, and can be reused in advanced reactors or recycled. Chemical toxins do not have a half-life, they are poisones indefinitely, like cadmium in solar panels. Nuclear \"waste\" is great.",
"Half-Life of 24,000 years. It's fucking Pandora's Box. NO human enterprise can keep its shit together for that long. And then twice that again. The literal dawn of reason in humanity was 10,000 years ago, when we know they had oral traditions from the Vedas. This kinda shit right here is why the quote: **Paleolithic Emotions, Medieval Institutions, God-Like Technology** Is meaningful. EDIT: Some helpful information: [ URL_2 ]( URL_3 ) [ URL_1 ]( URL_1 ) [ URL_0 ]( URL_0 ) Thanks to /u/dbdatvic for the heads up I might want to include this, since my view is sounding perhaps a bit alarmist. I DO think that there is a lot of things we don't know, as the public, and I believe more my friend [Helen Mary Caldicott]( URL_4 ) than I do more governmental agencies, but take it as you will.",
"Going to attempt an eli10 on this: The waste is like the sun. It puts out light, and things like light, that you can't see, and that light can hurt you just like too much sunlight can. Big governments aren't as much against it as little governments are, like towns and councils, because people don't want to hold onto it or have it stuck in the ground near their homes. Remember those X-rays you got? If you got way, way too many of those, you could get sick. That's why doctors leave the room while they take the X-ray, because they might do a lot and be close to a lot, but you only get a couple a visit. The X-ray is actually a lot like the stuff that comes out of the waste, and not just for how it can make you sick. We can block it with lead, and we can block it with other stuff as well. Water is pretty popular; it's cheap, and it works pretty well for what we're trying to do. Another way the stuff it makes is like light is that it gets dimmer the farther away you go, and there's only so much the source can give before it burns out. So, you can dig a big hole in the ground, build basically a big swimming pool, seal it to prevent leaks, put the waste in, and cover it with water. Then we watch it from a small distance to make sure nothing happens to it, and we let it burn itself out over time. After about 150 years, barely 3% of the waste is still dangerous. Once the material burns out, we can reuse it. The hardest part in the whole thing is getting someone to agree to put such a pool in their town, because people mostly don't know how it works, so it makes them afraid, but if the government wanted to pay me to hold onto it, and they gave me the money to dig the hole, build the pool, stick it all in, and then babysit it, I would. I worked with this stuff in the Navy. It got less radiation working in the plant than the guys working on the flight deck, because they were standing in the sun and I was deep below in the ship, surrounded by metal above and shielding around. The next-hardest part is about making something that'll last for that long without anything leaking, but that's why we have to watch it and check it to make sure it doesn't. We're great at building stuff good enough for people that'll last for hundreds of years, but not as good at building stuff that won't ever spring a leak for that long. That's one of the reasons why we have to watch it after we put it in the pool. The water itself doesn't become *very* dangerous, but if we're being responsible we have to make sure nothing corrodes and gets into water... But that's an engineering problem that you solve by building stuff, moving stuff, and being responsible. You can check how much radiation is coming off of the waste with a bunch of different detectors, the way the TV has a detector that checks for the signal coming off of the remote. That's the biggest danger out of all of them: People need to be responsible while they hold onto the stuff. It's not anywhere close to as bad as you see on TV or in your games, but you can't be stupid or careless with it either. It's fine. Like I said, I'd put some of it in my backyard if they gave me enough money to build what I need to build, and if they paid me to keep an eye on it."
],
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"https://www.cleveland.com/pdopinion/2009/02/nuclear_power_vs_clean_coals_d.html"
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[],
[],
[],
[],
[],
[],
[],
[
"https://www.scienceabc.com/eyeopeners/why-dont-we-shoot-all-our-nuclear-waste-into-the-sun-or-moon.html",
"https://en.wikipedia.org/wiki/List_of_radioactive_waste_treatment_technologies",
"https://en.wikipedia.org/wiki/Nuclear_transmutation#Artificial_transmutation_of_nuclear_waste",
"https://en.wikipedia.org/wiki/Fast-neutron_reactor"
],
[],
[
"https://youtu.be/0JfJEK3R1k0"
],
[
"https://www.world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-wastes/radioactive-wastes-myths-and-realities.aspx",
"https://www.nrc.gov/reading-rm/doc-collections/fact-sheets/radwaste.html",
"https://en.wikipedia.org/wiki/Radioactive\\_waste",
"https://en.wikipedia.org/wiki/Radioactive_waste",
"https://en.wikipedia.org/wiki/Helen_Caldicott"
],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3wkqo
|
Who is Navalny and why is he important?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkiy2c6"
],
"text": [
"Alexei Navalny represents Putin's strongest critic, and in a country known to assassinate people who go against the Russian government, it is kind of a big deal. Putin has attempted to assassinate Navalny twice and failed, but now he's returned to Russia. He asked his supporters to be present when he landed, and Russia has his plane diverted and land elsewhere where there were armed police ready to arrest him. Putin fears Navalny because he represents rebellion, and he cannot kill him now or he'll become a martyr. He has recently unveiled a plot by Putin to construct a billion dollar palace, and so it also shows Putin in a bad light. In essence, Alexei Navalny is Putin's greatest threat at the moment."
],
"score": [
255
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3wlvm
|
What is the internal difference between a CPU and GPU?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkizh4b",
"gkjbeqj"
],
"text": [
"The CPU has a relatively small number of cores - up to 4 in home computers, and up to 32 in high end workstation CPUs. Each of these cores if very fast and can do lots of different kinds of calculations. Meanwhile, a GPU has a large number of relatively weak cores, which specialize in calculations that are used mainly for displaying graphics. A single GPU core is much slower than a CPU core, but there are literally hundreds or even thousands of cores in the GPU, all calculating at the same time.",
"A CPU is like a pocket knife and a GPU is like a surgeons scalpel. The CPU is designed to be decent at pretty much everything. The GPU is designed to be really really good at it's one specific purpose, which in the case of GPU os doing lots and lots and lots of fairly simple and extremely similar calculations in very little time."
],
"score": [
11,
8
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3wvk4
|
If we breathe in O2, and exhale CO2, doesn’t that mean we lose stuff every time?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkj7fbc",
"gkj983b"
],
"text": [
"Yes. And the flip side of this is that trees (and all plants that photosynthesise) take in carbon dioxide and release the oxygen, gaining mass in the process. As someone said, trees don’t grow out of the ground, they grow out of the air!",
"Yes it does. In fact the vast majority of weight you lose (e.g.when you're dieting) is via the exhalation of CO2. That's why you need to eat and drink. You work like a combustion engine. You take in fuel (food) and oxidzer (air) and out comes CO2, and other \"combustion\" waste products (poo)"
],
"score": [
40,
29
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3x0p9
|
when Adobe Flash ‘died’, why did it cause every Flash program to stop running?
|
I don’t really have much of an understanding of computer programming, but I thought that Flash was just another program that was installed on a computer to access content. I read a story about how it caused a Chinese railway to stop running which is just mind boggling, but for simpler things like games and other interactive content, why can’t you still access them?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkj55ob",
"gkj6nht"
],
"text": [
"Flash applications won't run anymore because Adobe time bombed Flash player so that it would not run after 12 January. Microsoft and Adobe distributed these updates over a long period of time, which meant they were installed on the majority of computers. So, on 12 January, Flash stopped working on most computers. This approach was taken because Flash was never designed with security in mind and as a result was very, very insecure with no possibility of fixing it. The decision to do this was made, and announced over three years ago. It has been announced over and over again so nobody should have been surprised when it stopped working. But of course some people don't take warnings seriously.",
"Adobe specifically included a kill switch in all Flash updates since they decided to finally end it for good, in order to avoid a Windows XP/Internet Explorer 6 kinda situation. The browser maintainers also did this separately, so browser refuse to load the Flash plugin. This is very rare to see for this kind of program and only goes to show how huge a security threat the existence of Flash was. If you *must* run a Flash SWF file, there is an open source player called Lightspark."
],
"score": [
41,
21
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l3x6su
|
Why are longer limbs especially arms much more common in girls than guys?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkjassh"
],
"text": [
"It's not that their arms are longer, it's that their waist and hips are set differently than guys. If you ever look at a girl's belly button, it's much higher in their abdomen than a guy's. This makes their arms seem longer as a ratio to their waist, but past puberty, men generally have a larger arm span to height ratio, meaning thier arms are usually longer than women's for a given height."
],
"score": [
17
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3x80n
|
How is it so easy to confuse boredom and depression? And why are they, being dramatically different things, very often associated with each other and often amplify eachother?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkjmimy",
"gkje97k"
],
"text": [
"Hi I'm on psychology degree with plenty of friends suffering depression, not an expert but done my research. First, it depends of the POV, from external one it MIGHT (because both can be experienced very differently) look the same because in essence the sufferer is apathetic and look like they do nothing, but from the one suffering it's not the same at all. Depression leech on your physical and mental energy, you're physically enable to do pretty much anything nor feel anything, depressive people are nothing but empty shells (again it varies in intensity but that's the main symptom). Bored people on the other hand do not suffer from this lack of energy, just the lack of things to do. On a ELI5, boredom is a full battery with nowhere to be plugged in, while depression is an a empty battery, that actually often try to get plugged. And it comes to the second point, why does boredom is associated and amplify depression? Well, as said in first point, because both aren't doing anything, but for the depression it adds guilt on a already pit-bottom mind, you CAN'T physically do stuff even if you had the slightest motivation to do it, and you're feeling guilty about it. The lack of purpose lead to more apathy, less motivation, even less energy, so on and so forth, and depressive people suffer a lot because of that because of the confusion between laziness and a real mental disease. TL;DR: It's confusing because it looks the same but it feels nothing alike, one don't know what to do while the other one is physically and mentally suffering . And it amplify depression because doing nothing in western society is one of the greatest sin no matter what's the cause, and put guilt on already apathetic mind",
"> How is it so easy to confuse boredom and depression? It isn't. > And why are they, being dramatically different things, very often associated with each other and often amplify eachother? They aren't. I completely reject the premise."
],
"score": [
7,
5
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3xfyh
|
What is bitterness, really?
|
I've looked through tons of ELI5 questions on bitterness and the majority seem to accept "bitterness" as this abstract concept that simply exists, like if you were trying to explain what wind looks like. As a cook and bartender, I enjoy bitter foods daily - amari, bitter veggies, grapefruit, lemon pith, coffee. I can go on and on. I know what it tastes and feels like. But what is it, on a chemical level? Why do so many poisonous or even unnutritious things taste bitter? How do our taste buds pick it up and what is the "bitter" signal sent to our brains? Why is it neutralized to a degree by other specific flavors? For an alternative and extended answer to this question, can you extrapolate on this? If humans publicly and consistently accepted and appreciated bitterness in foods, would we continue to have a nature-based aversion to bitter foods, or would it be seen as a generally desirable characteristic? Sugar and salt are the most obviously sought after, but appreciation for acidity is becoming more and more common and I wonder about the effect of marketing and publicity as a means for changing perceptions of flavor. **In short, is perception of bitterness as a negative (less desirable) flavor largely or even completely driven by environmental influence?**
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkjggix"
],
"text": [
"Bitterness is perceived via an assortment of taste receptor proteins, the TAS2R family. It's hard to predict from the structure alone which substances activate those receptors, but generally a lot of secondary plant metabolites do, and a lot of those are a defense system by the plants and thus toxic. At the core, it's an avoidance mechanism to prevent you from eating stuff you shouldn't eat. You'll notice that kids don't like bitter stuff, not at all. They are even more sensitive to it, which plays into their dislike for certain vegetables. However, we humans being smart, we figured out that there is bitter stuff we can eat safely and came to like it - but that is pretty much always an acquired taste, learned behaviour overriding the innate preferences."
],
"score": [
34
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l3xzp8
|
Why are sinking ships in movies portrayed with metal screeching sounds while going under?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkjv8ts",
"gkjiuef"
],
"text": [
"There are stories (true) about submariners who would listen to the ships sink after torpedoing them - the sound of a ship dying underwater is haunting to fellow mariners even in war time. It was also true of the surface fleet - as they could hear and confirm a kill by the sounds of the sub coming apart. So the noise it real - Hollywood obviously enhances it - like most everything else. The structure of a hull is designed to resist the forces of the water being applied to it - this is what buoency is. The moment it stops resisting is when the sea wins. This resistance is along the entire length of the ship and although it is a very dynamic load (load of the ship, waves, rise and fall, rolling etc) these loads are designed into the structure. But when that structure fails then you have loads applied that are not designed for or that exceed the strength of the material and it fails - violently. Like ripping itself apart or snapping. And this material is metal - so the sounds of metal grinding onto itself, snapping and ripping open is like a soda can x1000 being crushed.",
"To make it sound more dramatic, of course. Same as with crashing aircraft typically featuring Jericho trumpet sounds - which, in reality, were a fancy little gadget Nazi Germany planted onto its Stuka dive bombers as a literal terror weapon. Additionally, do bear in mind that water actually weighs a lot. So if one \"half\" of the ship is rapidly flooding while the other half is still dry, it *does* put a considerably amount of stress on the ship's structure."
],
"score": [
26,
4
],
"text_urls": [
[],
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}
|
[
"url"
] |
[
"url"
] |
|
l3y750
|
Why do we say "humans are social creatures" like there're other type of non social creatures exist? I've been trying to find a case of a creature that's non social and couldn't find any on google. How can anything not be a social being?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkjkxwi",
"gkjl42h"
],
"text": [
"There are lots of animal that are not considered \"social\". It doesn't mean they never see others of their kind (they have to procreate), it just means they spend a majority of their time alone or only with their offspring. Examples would be mountain lions, Tasmanian devils, female cheetahs, and many many more",
"That’s because a lot of animals are not considered social. They are called “subsocial” which means that they only care for their young (which doesn’t count to be called social) and only meet other animals of their kind when they need to find a mate. There are a lot of social animals that live in groups or herds. Think of wolves, lions, bison, dolphins, etc. Humans are “social” as they form groups or “societies” to live together."
],
"score": [
10,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3y9zs
|
How your body makes sure you don’t fall out of your (or any) bed while sleeping
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkjp7u0"
],
"text": [
"You actually can fall out of your bed, because short moments of tossing and turning are possible when you're not sleeping deeply. The urge to do more than just turn around usually only comes up while dreaming. During that phase two different brain systems keep body muscles from moving so you can't act out your dreams. When there's something wrong with these systems it might lead to sleepwalking and other disorders. Today we still haven't fully understood what's happening in our brains, so it's hard to be more precise."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3yw9e
|
The sun heats the earth, and it takes 8ish minutes for the sunlight to reach earth. Does any of the light from all the other stars we can see heat up the earth, even the tiniest bit?
|
I hopes this makes sense. English isn't my first language. I've spent 10 minutes trying to phrase this sentence coherently but it still feels like a weird sentence. Let me know if you don't understand and I'll try and explain my dumb question
|
Earth Science
|
explainlikeimfive
|
{
"a_id": [
"gkjyi07"
],
"text": [
"Yes, any wave from any part of the EMF spectrum will technically add energy to whatever it comes in contact with. Of course it's going to be extremely neglible since the energy transfer follows an inverse square law, the same as gravity."
],
"score": [
27
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l3z2ru
|
How can skateboarders Ollie from a high place to ground and not break their legs.
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkk4z5z"
],
"text": [
"Bending the knees on impact distributes force to the board itself, and ideally into the trucks and wheels if your feet are positioned correctly on impact."
],
"score": [
12
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l3zhk8
|
Why do we prefer to do certain things with our non-dominant hand/foot?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkkg2kx",
"gkk9vsf"
],
"text": [
"maybe because it is easier, or its the “proper way”? im a lefty but i do prefer using my right hand on certain cases, like using a mouse for example. aside from those two reasons, i can't think of any other else. atleast for now. maybe OP what the dominant hand also have a large impact on it, for example, most people are expected to be right handed so everything is designed for them. so for them, they will use right hand almost exclusively. but for left handed, they will have to learn to use right their hand on certain things(like doors). but if it's not required, then they can use their left.",
"I’m not sure if I’m allowed to comment without explaining on this sub so I proceed with caution What things do you prefer to do with your non-dominant hand/foot??"
],
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5,
4
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|
[
"url"
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[
"url"
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|
l3zpds
|
If radio waves have been used for over 100 years then why are we just now using waves like 5G to communicate?
|
Earth Science
|
explainlikeimfive
|
{
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"text": [
"We never needed it and the electronics are more complicated. The frequency range of 5G gives you a high data rate, which we only started to need with mobile internet everywhere, but you pay for it with a very short effective range. For previous applications, a long range coupled with a lower data rate was far more desirable. You can call a dude half the world away on shortwave, with 5G you are limited to a few kilometres at best.",
"5G isn't \"just waves.\" They're waves of a higher frequency. Back in Ye Olde Times the only broadcast radio was AM and you'll notice the tuner for that floats around in the range of a few kilohertz. FM came out and is in frequencies up to about 108 MHz. But it's not just about the waves but how we use them. The real secret sauce behind 5G isn't the frequencies used but the technologies (hardware and software) used for putting useful data in that wave, and getting the data back out on the other end. 802.11b Wi-Fi operates on 2.4GHz and is capable of up to 11MBPS data rate, 802.11g using the same 2.4GHz band can put through up to 54MBPs, and 802.11n utilizing 2.4GHz can theoretically push up to 450MBPs. See how as technology got better we got a lot more data through the same wavelength?",
"5G uses radio waves too. 5G refers to the method of putting information on the radio waves and specific frequencies used as standards so that all devices inter-operate properly. These methods, of course, rely on high speed circuitry and technology not previously available (at a reasonable cost or reliability). There are many theoretical methods to encode information on radio waves and many of them have been known for a long time - some are just very difficult to implement and 30 years ago, before the internet, there wasn't much demand for it either (and \"demand\" means people willing to pay for it, not just a desire for it)."
],
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10,
9,
5
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|
[
"url"
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[
"url"
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|
l40k2d
|
What exactly is the significance of the USSR dissolving and what did it mean for the entire world?
|
I know very little of russia and trying to learn it’s history is very complicated. I still don’t quite understand what the USSR represented but i know it dissolving was a big deal and impacted the world in a major way.
|
Economics
|
explainlikeimfive
|
{
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"text": [
"The USSR was multiple republics put into a central authority that was based in Moscow. They were like the managers, and the other small republics, workers. The US and the USSR did not like each other because they thought the other wanted to invade the world. The US also wanted people to be able to own businesses and keep the money they made from the business. The USSR wanted the government to own the business, and give everyone the money. When the USSR fell, it was important because the US thought it meant they were right. Also, it meant that another big war wouldn't happen, and that many people would not die.",
"Well, the USSR and the United States had a very contentious relationship after world war 2 which you’ll know as the Cold War. The USSR wanted to show that their way of life was better than the democracy/capitalism of the west. Lead to all sorts of things, like the space race, where the two countries were trying to exert dominance. In America everyone became afraid of communism, and you had things like “the red scare” where everyone in the US was paranoid of communists infiltrating American society and subverting it. Idk how every day Russians really felt about Americans, but probably similar. You’ll also remember that the USSR controlled the eastern part of Germany (after WW2) and the western allies controlled the western part of Germany after ww2. So this whole Cold War stuff manifested itself in really weird ways if you lived in Germany from the 50s until the late 80s. Berlin was split right down the middle with eastern Berliners living pretty shitty lives and western berliners living wild and free. People were always trying to sneak over to the west. Anyway. In the late 80s the USSR sorta fell apart and broke up into all of its constituent countries, one of which was Russia. They probably just ran out of money and couldn’t keep it going. Plus many point to this as a prime recent example of why communism just doesn’t work at scale. The Berlin Wall came down and Germany was made whole in a way. I’m sure it was chaotic for a while, almost imagine like the United States breaking up and all the sudden the state you live in is now it’s own country and you gotta figure out how to make it work with all the other new countries surrounding you. I think for the west it as a big deal because it meant the Cold War was over. That ostensibly the western way of life prevailed over communism, and the constant threat of mutually assured destruction via nuclear annihilation had relaxed considerably. Nowadays you occasionally see Russia trying to reclaim some USSR territories with moves like the annexation of Crimea (which was part of Ukraine that Russia just sorta took back - both Crimea and Ukraine were formerly part of the USSR.) (P.s. I was born in the mid 80s and this is just my high-level impression of what it meant for the USSR to fall, someone will probably come in here and explain it way better)",
"It meant that the Cold War was over and Pax Americana has begun: the US won the race to become the world's only superpower. Since the USSR crumbled, the US could now expand its influence to formerly contested regions such as the ME and Eastern Europe. More wars broke out after the USSR dissolved compared to the Cold War era because simply there was nobody there to do anything about it."
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[
"url"
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[
"url"
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l40x6h
|
- Explaining Labor Unions & Why Companies May Be Anti Union
|
Other
|
explainlikeimfive
|
{
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"text": [
"Its fairly straightforward. Unions give workers stronger leverage when negotiating with management due to the fact that all agreements are collective, and disagreements with the union can risk a strike or walkout of the employees. Obviously corporate management dislikes unions for exactly that reason. It lowers their own leverage when negotiating, which they have a lot of when the work force is not unionized as they can fire and punish individual employees without explanation or rationale, which makes it easier to control them.",
"As an example Your company employees 200 people on the \"front lines\", say grocery clerk stockers and cashiers or assembly line workers, etc. In a given year, with 10% turnover per year, they fire/have quit 20 people and hire another 20 people. That's almost 2 people coming and 2 people going, per month. As a worker you want to negotiate more money or different working conditions. In this situation, as one of 200 front line employees, your only leverage is the cost of training a replacement. If you ask for more than the cost of training a replacement, it makes no sense for the company to give in. And since they replace 10% of the workforce per year, they've gotten the cost of replacement down pretty low and largely bake that into their expense estimates already. You're just one of that years' 20. Additionally, the company also has to weigh the risk of you letting other people know you got a raise. So giving in to you isn't an isolated cost, but rather also a risk that can generate cost from other employees. This strongly incentivizes the company to not deviate from whatever compensation structure they've committed to on your behalf under almost any circumstances. Now, let's take the same situation and put you in a union with 200 people. Now the risk differential is very different. It isn't the cost to replace 1 worker, it's the cost of all 200 workers potentially walking off the job and going \"on strike\". And in many states/countries there are additional labor protections afforded unions which prevent the company from even trying to replace all 200 workers with \"scabs\", significantly increasing leverage. At its core, that's the point and value of unions. Where unions get a little more complicated is that in order to \"strike\", walk off the job, these workers will lose their immediate income. In all likelihood they are a lot closer to the poverty line than the owners of the company, meaning in theory the company could attempt to just wait out the workers (or more specifically, their pocket books). Unions try to hedge against this with \"strike benefits\", collecting wages during non-strike months to build up a reserve to pay out to workers during a strike to keep them solvent for longer. Unions also often try to create benefits tied to the union, not the company, to keep the workers more loyal to the union than the company. They'll cover legal bills for work related lawsuits under the theory that one workplace lawsuit benefits everyone (if one person is harassed enough to sue, likely more are as well). And all of these activities are administered by someone, getting legal advice from somewhere, etc. This means being in a union is a long-term investment. It's a bit like insurance where you pay hundreds of dollars every year *in case* your house burns down. But generally your house doesn't and so you just lose money without ever necessarily seeing the direct benefit. It's why banks require people to purchase home insurance, people are bad at risk evaluation and weighing long-term benefit against short-term cost, left to their own devices many people wouldn't buy insurance. Similarly, many pro-union states/countries/companies will try to mandate that workers all must join the union (or at least pay the dues). As to why your company is making you watch anti-union ads, that's what they're trying to exploit. They're trying to exploit the short-term costs of the union in order to dissuade you from being enticed by the long-term benefits. Whether that cost benefit analysis is actually in favor of a union or not isn't a question I can answer for you, though I would argue that them showing that video would immediately make me suspicious. Not that I have to tell you that, since your question by its nature suggests you are as well.",
"Labor costs are some of the biggest single costs for an employer, so an employer's goal is to keep labor costs as low as possible, because that means the investors in the company have more money left over for profit. But the business depends on labor. Without a union, it is each individual worker vs. the company and it is easy for the company to say \"if you don't like the wage, then you're fired.\" But with a union, the workforce organizes as a collective unit. Now they have the power to say \" give us a fair wage or we walk and your business is finished.\" Lot of companies use scare tactics because unions make business more difficult. It is the tension between capital (shareholders/investors/ Wall Street) versus labor (workers/ Main Street.) It is the oldest conflict in America.",
"You are experiencing the timeless struggle between wealthy capital owners, and their subjects/employees. In America talking about salaries, talking about money, and talking about class is taboo. The rich need to control the conversation and prevent the poor from becoming aware of their common predicament. The unions are simply the way the poor improve their situation and take back some of the capital that has been taken from them over the years.",
"I think the fact that one of the first videos they show you is about why unions are bad should be a major red flag that you're going to need a union very soon.",
"Unions basically gather the workers together to act as a group rather than as individuals. If one person says they won't work until they get a pay rise it is easy for the management to get rid of them and hire someone else, if the majority of the workforce says it, then it is extremely difficult for the management to replace them so they are more likely to give them a pay rise. So far this is good for the workers and not too bad for the management since they can link the pay rise to productivity or something similar and actually profits may increase. The problems then come when unions try to exercise this power of the workforce outside of what the workers really want. This can be for political reasons or from extortion or anything else, most countries that have a long history of acceptance of unions and organisations have smoothed all this out with the legal system; however America had a history of where criminal organisations (the mobs) took over some unions and were able to make huge sums of money deciding which buildings would be built, which trucks would deliver etc. So to clarify unions within a properly functioning democracy work well, in corrupt societies or poorly functioning democracies they have a potential for problems.",
"You know the phrase “divide and conquer”? It’s much easier to win a battle when you’re fighting small groups or individuals rather than fighting a whole huge army. Even better if you can get those small groups to pick fights with each other and all you have to do is mop up any leftovers. You win by making your opponents weak and disorganized. Companies and bosses are always in competition with workers: companies want to get their employees to do as much work as possible for as little money as possible. Workers, on the other hand, want to be paid well and not be overworked. Companies try to win this battle by dividing and conquering their employees, and they usually win because they have all the power: “here’s what we’re willing to pay you — accept it or you’re fired.” As a worker who needs that money to survive, how could you put up any real fight? Even if you do, there are thousands of other hungry workers to replace you who might even do the job for less money. Unions are the best protection we have against dividing and conquering. One single employee is weak and vulnerable, but when a whole workplace or even a whole industry band together they are tough to push around. You can fire one employee you don’t like, but you can’t fire all of your employees or there will be nobody left to make your widgets and doodads. Unions use their collective power to make the battle between workers and companies a little more fair, and work to protect the safety and wellness of the workers from the greed of the bosses.",
"If you get run over by a UPS truck, do you want UPS to decide how much you're compensated?",
"Others have provided good answers so I’ll just add that unions are an essential bulwark under capitalism for workers to have some collective power against the private sector and business interests.",
"Unions exist to avoid interactions like this (imagine a factory in a 'company town'): & #x200B; Worker: Hey boss, the safety interlock on that press that I've been telling you about for months has finally failed. Boss: Just bypass it, those things are expensive and we have a quota to meet (note there is \\_always\\_ a quota to meet) Worker: But boss, I'd rather not get my arm torn off Boss: Just get it done, and if you won't **there's 5 more lined up out front** of the factory just begging to take your job! & #x200B; Either the worker is fired, or maimed and then fired. This happens when there is a significant imbalance in labor supply / demand. The factory employer controls essentially 'all' the demand in a given locale. Each worker controls just their contribution. As often happens, there are more workers than jobs. Pay can only go so low, but less obvious things can be cut. Hours can be lengthened, poor safety conditions, poor after-injury care (hurt? Fired!), no retirement scenario supplied (too old to work? Too bad, starve, not my problem.) & #x200B; Unions provide a balance of power; now the employer can't just cycle though the line out front -- they have to deal with all the workers as a whole. & #x200B; The 'ruins resident lives' is an artifact of a overbearing / overpowered union. In the first scenario, a substandard worker is just fired. In a union scenario there is extra process to go through. A 'slightly' substandard worker won't be worth the effort. A union can make the firing process so difficult that a worker has to be horrendous to be worth the effort, so in that sense it can down the average quality of care. A good union won't cause that. & #x200B; 'Back in the day' the concept of workers comp, OSHA, wrongful-termination, wrongful death, and personal-injury lawsuits were far less of a thing. Nowadays many of the things unions won are encoded in law, but even then successfully wielding the law may be out of reach of individual workers. I think there is still grounds for a healthy debate as to if unions are necessary in any given sector."
],
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|
[
"url"
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[
"url"
] |
|
l40yir
|
Why can other mammals easily give birth by themselves but humans seem to need to put a lot more effort into giving birth?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkkwr24"
],
"text": [
"Bipedia and big heads makes us born underdevellopped but still quite big for the woman pelvis. It is a problem of balance between head and hips size."
],
"score": [
7
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l40z0c
|
If you have bad eyesight and look through mirror at something far away would you need glasses to see it clearly?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkkx1yy"
],
"text": [
"Yes. This is actually how many tests for nearsightedness are conducted, to simulate a much larger distance than the (usually small) test environment allows. Physically, basically nothing changes about the manner in which light is traveling when it hits a mirror. **You can reason about the light coming from a mirror as though it were coming through a window into a (mirrored) universe.** So if things look blurry through a window, they also look blurry through a mirror. (Granted, I am assuming the mirror is flat. A curved mirror could provide the equivalent effect of a corrective lens.)"
],
"score": [
7
],
"text_urls": [
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}
|
[
"url"
] |
[
"url"
] |
|
l411ya
|
World record for holding your bresth is 22 minutes and 22 seconds, how is this possible if the brain cannot go without oxygen for more than 5-10 minutes without brain damage?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkkyg80",
"gkkzfnb"
],
"text": [
"These are people who have trained a lot to hold their breath in this way. The techniques they use are both to reduce the symptoms of oxygen depletion as well as reduce oxygen consumption. So they are able to extend their time holding their breath to around 12 minutes without aid. The 22 minute record was set by breathing pure oxygen under pressure to increase the amount of oxygen in the blood and lungs.",
"The record attempt is performed in cold water. It will reduce your heart rate and metabolism reducing oxygen consumption. On top of that they usually inhale pure oxygen for an extended period of time before going under water. That way their oxygen levels are higher than usual. & #x200B; And this combination of reduced oxygen consumption and higher oxygen levels when beginning holding your breath is whey you can go past the 5-10 minute mark without permanent brain damage."
],
"score": [
10,
4
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
|
l415ag
|
How did we get to the point where a smartphone cost more than a laptop?
|
Technology
|
explainlikeimfive
|
{
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"gkkz0sr",
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"text": [
"There are plenty of smartphones that cost less than a laptop, and plenty of laptops that cost more than a smartphone. But if you compare a *high end* smartphone to a *low end* laptop, then yes, the smartphone would cost more.",
"A high-end smart phone does not cost more than a high-end laptop, and a low-end smart phone does not cost more than a low-end laptop. I reject your premise. If you want to know why smart phones _can_ cost as much, it’s because of miniaturization.",
"I get you OP. My iPhone costs a grand but my laptop costs $400. I believe we got here because people now spend more personal time on their phones, which can do some of the same functions as a laptop. I use my personal laptop maybe 8-10 times a year. I use my phone 8-10 times an hour. If I were gaming or working from my personal laptop, I would buy a more expensive one. I compromised and invested in the platform I use the most.",
"Customer demand for smartphones vs. laptops. People will still line up to pay $1000+ for smartphones.",
"Well, that isn't always the case as already pointed out, but fundamentally a modern smartphone has pretty much all the same components as a laptop (screen, CPU, memory, storage) along with stuff that a laptop typically \\*wouldn't\\* have (GPS and mobile network connections). So, even though the smartphone is smaller it's arguably more complicated and thus harder to manufacture.",
"It’s harder to engineer and manufacturer on smaller scale. It’s easiest to fit the necessary components into a desktop computer. Harder to make them smarter and fit just right into a laptop. Much harder still to do so into a tiny smart phone. The processing, storage capacity, etc are not that far off between a laptop and smart phone in spite of size differences"
],
"score": [
47,
19,
7,
3,
3,
3
],
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[],
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|
[
"url"
] |
[
"url"
] |
|
l426oy
|
how is the bottom of the ocean mapped and how accurate are the results?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkldg4k"
],
"text": [
"Mostly they use a form of radar/sonar but water can cause issues with mapping. Results are pretty accurate. But the ocean is just big and it takes time"
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l42qav
|
How does a trunked radio system work?
|
please as basic as you can lol
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkmtgwj"
],
"text": [
"The simplest way it was explained to me is to think of a bank. Each teller is a different frequency. You stand in line. When you transmit, you go to the first available teller/frequency. You stand in line again. When you transmit again, you again go to the first available teller/frequency which may be a different teller because another person is using the previous teller/frequency to talk with their dispatch from another agency."
],
"score": [
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
l43jgx
|
Why does caffeine have a calming effect on some individuals with ADHD, as opposed to making their traits increase?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gknsly2",
"gklvpy5",
"gkm2smm",
"gko31ss",
"gkorgcn"
],
"text": [
"Clinical psychologist here. It's not that caffeine produces a calming effect, it's that caffeine improves function of the frontal lobe which is responsible for executive function, which oversees other operations in the brain. ELI5: Think of an ADHD brain as one of those old-school factories where the foreman's office was above the line, except the foreman is sleeping and so normal operations slip. Caffeine (and other stimulants) wake him up so he can do his job overseeing the work. Non-ELI5: There are two predominant models of ADHD. Barkley's inhibition model and Rapport's working memory model. Barkley's model suggests its difficult not to blurt out the answer. Rapport's model posits (if we use a metaphor) that if a behavior was a 'photograph' , that those with ADHD struggle to hold that 'photograph' in mind as a guide for their behavior.",
"The best ELI5 I can do: A person suffering from ADHD has a weak response in the reward center of their brain. This causes things to be less intriguing and an interests short lived. When a stimulant is added, your brain releases a greater concoction within the reward center in such a way that the brain struggles less when trying to remain on task. The subtle soothing feeling is due to the brain being less strained/ task saturated",
"It’s a stimulant. The medication to treat ADHD is also a stimulant (adderall for instance). It helps people focus and control what they’re putting their focus on.",
"The way I understand it, is that the brain of a person with ADHD is like driving a manual, or standard car really fast in first gear. The engine is racing very quickly. But if you move up to 2nd or 3rd gear (I.e. take a stimulant of some kind), the engine calms right down.",
"So, you're in class. The teacher walks out of the room and starts talking with a visitor. She is engrossed in her conversation, and loses track of time. Kids being kids, you all start whispering to each other instead of doing your school work. It gets louder and louder. Eventually, paper airplanes are flying through the air, and little Johnny is running across the desks. That's an ADHD brain. Caffeine keeps the teacher on task. She doesn't get distracted by her conversation, and keeps the class focused on the task at hand."
],
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30,
3,
3,
3
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|
[
"url"
] |
[
"url"
] |
|
l43q8u
|
does the container of drinks really change the flavor?
|
Have it be aluminum, glass or plastic?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gkm5jma"
],
"text": [
"Glass leaches fewer chemicals and is unaffected by temperatures and light generally. Other containers tend to be more effected by light (plastic) and temperatures (aluminum) so the glass is as close to pure taste as you can generally get."
],
"score": [
7
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
l446i6
|
Why is men stealing girls panties such a big thing in pop culture? Seems pretty gross and I'm a dude.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkm4ii1",
"gkm54gc",
"gkm2e0j"
],
"text": [
"I've seen it in pop culture in two main categories - old white men in american cinema/tv and any age in Japanese animation. I always assumed it was a fetish caused by severe sexual repression. If you've never normalized seeing a woman in underwear, the underwear itself takes on a sexual aspect, or something like that.",
"It's a common fetish. Panties are in intimate contact with female genitalia. So there's a lot of cross-association. I'm not sure what else there needs to be to it.",
"Perhaps most writers are pervs and that’s they’re outlet for the panty raids they wish they could have"
],
"score": [
9,
5,
3
],
"text_urls": [
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|
[
"url"
] |
[
"url"
] |
|
l44mae
|
Why can a major news network set up cameras in a public space without asking every person to sign a release form, yet youtubers seem to blurr out everyone in the background
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkm6xqb",
"gkmees1"
],
"text": [
"In the US you can film on public space without issue. If you're in public its almost always OK to be filming (there are some exceptions). However, you do need permission to film on private property in most cases, which again there are some exceptions. I don't know what youtubers are doing blurring people out, but there's nothing wrong with that. Protecting people who did not know they were being filmed is totally fine. Its not mandatory in public, but its certainly OK to do.",
"There's several overlapping issues going on here: 1) Anyone is free to record anything they want in a public space. 2) You have a state level right to the exploitation of your likeness. How strong this is varies from state to state, but is notably strong in California. Anyone who is broadcasting video in California (which includes every major youtube channel) is subject to California law on this. What this means is that while anyone is free to record you in public, they are not *necessarily* free to broadcast that recording of you. Right to likeness is a complex area of the law and to be on the safe side nearly everyone who makes videos for mass broadcast blur the faces of people who haven't given them a signed release. 3) Right to likeness laws are state level laws, there is no Federal level equivalent. However, the 1st Amendment exists at the Federal level and offers protections that supersede any state level laws. In particular, the 1st Amendment offers broad protections for content related to a \"newsworthy\" event or subject. Generally speaking, anything that a major news network is going to broadcast is going to be considered \"newsworthy\" and is therefore protected by the 1st Amendment. Because these broadcasts are protected by the 1st Amendment, state level right to likeness issues don't apply to them and so there is no need for faces to be blurred."
],
"score": [
48,
38
],
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}
|
[
"url"
] |
[
"url"
] |
|
l44zii
|
why animals in the same family don't prey on each other?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkmc5qe",
"gkmskbg"
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"text": [
"If an animal is fighting a similar sized member of it's family to the death, the winner is not going to come out unscathed. Similar sizes and strengths means the winner would most likely be injured in the fight which hinders further opportunities to get food. Certain animals do eat the young of their own species. Fish are the most common as the young are often very small. Since there's so many of them, it's survival through numbers. Other animals like birds can have severe sibling rivalry. The larger baby birds will attack or claim the food from their smaller siblings in the nest which can case the smaller siblings to not thrive. Another issue with eating your own species is diseases. There are specific diseases caused by prions, which are improperly folded proteins, that only infect others of the same or similar species if they are consumed by them. One such disease, Mad Cow Disease, spread because cow products were mixed into cow feed.",
"Because our behavior is most fundamentally shaped by the evolutionary selective pressures our ancestors and their competitors experienced. Different environments have different selective pressures, but one selective pressure which operates across almost all situations is that genes that code for attacking your family members are genes for getting attacked *because your family members share your genes*. The basic point is that any gene that codes for attacking your family members got outcompeted by genes that coded for protecting your family members."
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l45lrb
|
Why do “streaks” feel so important for quitting vices/addictions or achieving goals? For example, why does it feel like a bigger achievement to say “I haven’t had any fast food for an entire year”, than “I’ve limited the amount of fast food I’ve had in general”.
|
Biology
|
explainlikeimfive
|
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"I didn't smoke cigarettes for 425 days, which means 80,000 times that I wanted to smoke, I didn't do it. That's pretty impressive. It also helps to be like \"well shit I'm not gonna break the combo now\"",
"Because “I’ve had no fast food in a year” means, no fast food in a year. “I’ve limited the amount of fast food I’ve had” means anywhere between 0-99% of the normal amount of fast food, and for an undefined period of time. It doesn’t say anything about how much you’ve actually restricted yourself, and doesn’t indicate anything about how successful you’ve been. The longer you go, the more situations you are going to run into where you might be tempted to do something again, “Just this once.” Quitting things can be hard. I can say I haven’t had any fast food since yesterday, but that doesn’t mean anything, if I go and have fast food later today.",
"Because of the human condition, it's easier to self control when there's nothing to control. A little bit of something bad means now you have to control it in focus. A whole lot of nothing means you only have to control avoiding that thing. You don't have to control the amount you take, not how often, not when, not why, and not where.",
"It creates value in it's size. Think about a rubber band ball. One rubber band has no value - you wouldnt really care if you lost it. 10, OK, you're getting somewhere, 100, neat, 1000 - you'd be sad if something happened to it. The more you've added to the total, the more you want to keep the progress going and the more important it is to you. That makes it easier for you to avoid the temptation because you know just how much you'll loose by slipping.",
"When we accomplish something we perceive to be difficult, our brain releases \"feel good\" chemicals. A streak is a reminder of progress, which feels good. And, people usually praise specific accomplishments. Praise also makes us feel good. \"I lost 30 lbs\" usually gets a better reaction than \"I lost some weight.\" So our brains are conditioned to like specific outcomes, which reinforces the power of streaks.",
"for alcohol i've actually heard from a therapy form that allows something like one glass of wine every evening, teaching people to live with alcohol and as far as i know it works better than the no alcohol therapy (less people getting addicted again) i know, this does not answer your question, its just some additional knowledge"
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l45qd9
|
how does a country like the USA produce exactly as much electricity as needed at all times. Where does excess power go when not needed?
|
Technology
|
explainlikeimfive
|
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"One one side, you regulate the output of your powerplants to meet demand. That can be complicated with some plants, so the system is set up that you have base load plants, that will essentially run at constant production, mostly nuclear and coal, and peak load plants, which can react quickly to changing demand, that is mostly gas. On another side, you can store excess production. That's done with pumped storage plants. Excess energy is used to pump water into an uphill reservoir, from which it can be quickly released downhill through a water turbine to produce electricity again when the need is there. Overall, it's a fine balancing game between all the different sources and the changing demand. But the folks running that game have lots of statistical data on how demand changes over time and can predict what they have to do based on that.",
"Used to operate a gas power plant. A large power company has a central control center. They predict and react to demand and direct starting and stopping of units. Any plant with variable load will likely have an automatic control that can change a plants megawatt output remotely. In the US like other countries our grids are very large and interconnected, like multiple states and parts of canada for the west coast as an example. Power companies buy and sell power/reserve from other companies on the grid as needed. The control center was pretty good at their job, but we dont always produce exactly enough. This mostly results in frequency and voltage changes on a grid, but you'd need a large surplus or deficit for this to be a big issue....generating units like steam turbines will trip on overspeed or underfrequency to protect themselves if the load is too imbalanced. Other issues include things like lines overheating and transmission equipment tripping. You can use things like pumped storage to help use grid load, and can cut power to certain areas to help lower grid load.",
"In addition to what these other smart people have said, it's important to understand that we don't produce exactly as much electricity as needed at all times. We try to keep up with demand, but that doesn't always work. Prime example, summers in CA. They've been plagued with rolling blackouts for years in CA due to demand exceeding supply. They max out all the generation facilities but it just isn't enough. So they have to shut down parts of the electrical grid to make sure they don't go into an overload state. It would be nice if we had a way of storing power for an emergency at a large scale, but we don't. As others have already said, it takes a ton of monitoring and constant adjusting to ensure the power grid generation closely matches the need. Another thing to note is that the USA isn't one large power grid. Its many many many many small grids interconnected at times. So where I live in Oregon, my power mainly comes from hydroelectric with some other sources as needed. If my area had a huge power spike, the power would come locally. It's not like some big all equaling grid where power from other places automatically rushes in to fill the demand. We have the ability to move power to other areas, in fact Oregon sells a ton of power to California when needed, but it's very inefficient. The further distances you send power the more you lose. So in general, power is generated very close to the consumer. It'd be cool if this wasn't the case, because we could put all the power generation plants some places where nobody care, like the middle of the desert. But alas, this isn't the case.",
"Excess power goes into main power frequency, which fluctuates slightly. The power regulation system needs to stay into certain frequency range around 50 Hz (60 Hz in US). In Europe there was a power generation problem in Serbia few years ago. Since many clocks use the frequency from the main to keep clocks, they were getting slower because they were not generating enough power. URL_0",
"By starting up and shutting down power plants as needed. And computers. And lots of smart engineers watching it 24/7. It's a clusterfuck really, and nothing but a miracle that it works as well as it does. > Where does excess power go when not needed? It makes the generators in the powerplants spin faster, increasing the net frequency. Which you REALLY DONT WANT. It's imperative that there is no \"excess power\". Electrical energy isn't really stored at large scale (yet). There are a few battery facilities, and a few pumped hydro (think of it as a reverse hydro plant, which consumes energy to pump water up a mountain) stations, but nothing large scale. If we can accomplish that, it's a huge leap forward especially for unpredictable power plants such as wind and solar.",
"It actually does not. You will find that the grid frequency fluctuates all the time, it‘s just that it fluctuates very tiny amounts. If you pull more energy out of the grid than you supply, the frequency drops, and vice versa. As a first line of defense, the rotational inertia of the big turbines in the power plants buffer the changes, just like a heavy truck will react less quickly to pressing the accelerator than a light sportscar. Then you have power plants that are quick to regulate, like smallish gas plants, those get adjusted constantly in a matter of (mili-)seconds to follow demand. Coal plants are sort of in the middle, while nuclear power plants are extremely slow to adjust and wind or solar are depending on weather rather than energy demand. That‘s why we have stuff like pumping stations, which will store excess energy by pumping water up to a reservoir on a hill and release that energy later when it is needed.",
"USA also imports power from Canada. Quebec and Ontario for example. The US grid is tied in with Canadian grids",
"Power producers can only control their output voltage and frequency. Power generating stations produce high voltages which are eventually reduced to somewhere between 108-127V at your residence wall outlet. Sensitive equipment and other devices (wall clocks) rely on a constant frequency at 60Hz but are designed to accommodate fluctuations in voltage (108-127V). The generators constantly vary their output voltage to maintain a constant 60Hz output. This results in variations in your residential voltage which may cause your lights to shine a little brighter or dimmer or you coffee maker to heat a little faster or slower."
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l45vgn
|
If radioactive waste is dangerous because of the deadly radiation, why can't we still use that radiation in some way?
|
My current understanding of the disposal flow is: Fuel is used > Hot fuel is sent to cooling pond > Possibly some other longer form cooling pond > Barrels in a cave somewhere for thousands of years. If the waste is still dangerous, that means it has to be giving off some kind of energy right? How come we can't use that energy in some way to power something, or at the very least reduce the electricity required for the powered cooling ponds?
|
Physics
|
explainlikeimfive
|
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"The energy produced by nuclear power plants is due to nuclear fission of the uranium atoms, mainly the isotope Uranium-235. The uranium itself is hardly radioactive at all, and is quite safe to handle. The intense radioactivity given off by spent nuclear fuel is due to the fission products that build up in the fuel as it's used. These fission products are the fragments from the fission that produces energy. These include eg. Caesium-137 and Strontium-90. While these fission products are much more radioactive than uranium, none of them are fissile - that is, they can not sustain a fission chain reaction, which is needed to produce significant amounts of energy. That said, your question is important because in fact, over 90 % of the energy available from the uranium is still there in the spent fuel. This is because conventional nuclear power plants (BWRs and PWRs) only make use of the U235 portion, and about 95 % of the uranium in the fuel is non fissile U238. Even though U238 is not fissile, it can be used to \"breed\" fissile plutonium-239 in a special type of reactor, known as fast breeder reactors. A breeder reactor essentially makes it's own fuel, it produces more fissile material than it consumes, although eventually you'll run out of U238. So the technology to extract much, *much* more energy from spent nuclear fuel is there, but unfortunately, the political climate surrounding the nuclear industry is such that it's not in wide spread use. EDIT: Thanks for all the upvotes. I feel the need to clarify, that while breeder reactors are technically possible, they are not exactly a low hanging fruit. I mentioned them because they can extract almost all of the available fission energy from nuclear fuel.",
"Because it no longer generates enough heat to heat the water efficiently, and power plants only have so much room for fuel. But in today's age, we actually do recycle quite a bit of the used fuel. However, there is still a lot of stuff we can't recycle and has to be buried. Think of it like this. To make tea you should use pretty hot water, usually boiling or close to it. If you choose to make tea with water that was boiled an hour ago, you will probably get very weak tea and it will take forever to make. It would be an unsatisfactory product.",
"You’re not wrong - the “waste” from one type of fuel source can be reused as a different type of fuel source in another reactor, often after reprocessing it to remove certain impurities that mess with the chain reactions. But eventually you get to a point where the waste is in the form of elements that have very long half lives and don’t readily form chain reactions that give out a lot of energy quickly, so the output is too low to be useful in generating power, and can’t be sped up, resulting in (at present) useless waste that’s incredibly hazardous to most life on earth for very long periods.",
"If they could they would is the short answer. We use nuclear energy by converting it into turning water into steam, it's the immense heat it puts out that is valuable. The spent fuel is considered spent because it's not capable of generating the heat necessary for the primary system, and it's a question of whether it is economical to try taking further energy from it. It may be technically possible but the returns just too small to justify spending money on it.",
"Think of it this way: you could still make coffee from used coffee grounds, but it would be really weak. You'd still have coffee, but not a at strength level anyone would want."
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l465oe
|
How is the US government able to function and fund different things when they are in trillions of dollars of debt. Is this debt getting paid off? Who collects said debt payment? How does this all work?
|
Other
|
explainlikeimfive
|
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"So, the first misconception about govt spending is that taxpayers fund the government. They don't. The government doesn't take money from taxpayers and put it into an account then use that money to pay for government activity. The government pays for its activity by simply creating the money necessary to do so. If the govt needs $1.2 trillion for a stimulus package, they just create $1.2 trillion in new money and use that. The govt theoretically can't run out of money. They just print more when they need more. Taxes are what keeps this printing from driving inflation to unsustainable levels. By removing cash from the economy through taxes it reverses the inflation effect of printing money. The IRS collects \"debt payments\" via taxes. \"Taxpayer money\" is simply removed from circulation entirely, metaphorically burned."
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l4701j
|
Why is the sound, the sensation, or even the thought of dragging your nails on a blackboard so physically horrible?
|
Biology
|
explainlikeimfive
|
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"To simplify: Our outer ear is shaped specifically to make a specific range of frequencies much \"louder\". Meaning you can listen to a frequency thats outside this range thats loud and another that's inside this range which is, actually, quieter, and the pitch within the amplification ramge will sound lounder, even though its actually not. There are a few frequencies that REALLY get amplified. Biologically, the crys of babies are close, as is the warning signal of champanzees. Scratching on a chalkboard also just happens to fall in one of these ranges. Anything that falls in these ranges also increases stimulation between our auditory part of our brain and the part of our brain assocoated with negative emotions. In a study ( URL_0 ) they presented some of these sounds that were very unpleasant and got rid of JUST the frequencies in those sounds that fell within the range, and the sounds were much more pleasant. They also tried just getting rid of the high frequency, low, mid, etc and none of that had any effect on pleasantness."
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|
l4707o
|
why does muscle grow slow considerably for someone who has been working out for years compared to a new comer / why is it so easy to gain muscle earlier into lifting?
|
Biology
|
explainlikeimfive
|
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"The human body has a limit to how much muscle you can build (whatever that limit is). Everytime you hit the gym and gain some muscle, you're putting yourself a tiny little bit closer to that limit, which means you have less room for growing more muscle, which takes more time and effort and energy every day.",
"Sometimes lifters call this the \"Novice Effect.\" When you build muscle, your body is adapting to the stress of lifting. When your body is thoroughly unadapted to the stress, almost anything will cause an adaptation. But when your body is mostly adapted to lifting, more stress and more complex lifting programs are required to cause continued adaptation. So growing muscle gets slower and more difficult.",
"This question seems opposite of what I have experienced. After having worked out to the extent of becoming a physical beast when I was younger, I have since found it easy to put on muscle mass. Muscle memory. For instance, I may go a year or more without working out, lose muscle mass and start getting flabby. But once I do get back into the gym, I gain that muscle back fairly quickly. I set my goal at 3 months of working out to slim down and gain my muscle back. Proper diet is very important for gaining mass as well though.",
"MYOSTATIN & #x200B; The more muscle you have, the more myostatin your body produces. Myostatin tells your body to eat itself because its getting too big to sustain. You can only push yourself so far into this before the gains pretty much stop. Elite bodybuilders have been tested, they have less myostatin production and ramp up than normal people. Yes they use drugs as well. I used a lot of drugs to get as big as I could and lifted and ate like a madman for years but never even came close to the results these freaks of nature achieved. [ URL_0 ]( URL_0 ) This is a picture of a cow or whatever that has zero myostatin due to a genetic defect. It definitely does not work out harder than other cows. It just keeps growing because nothing tells it to stop. The only thing limiting it is its food intake."
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l474j3
|
How do electromagnetic waves (like wifi, Bluetooth, etc) travel through solid objects, like walls?
|
Physics
|
explainlikeimfive
|
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"So, when a ray of light hits something, it can basically do one of three things: It can go right through, with a slight angle that reverses when it comes out the other side, like light passes through glass or water. It can bounce off at an angle, like light does with a mirror or a bright piece of colored plastic. Or it can get \"eaten\" and heat up the object, like when light hits something dark. Objects are different colors because light is different wavelengths, and some wavelengths get eaten while others pass through or get bounced off. A solid \"red\" object is red because green and blue light get eaten more than red light, while red light bounces off more than green or blue. A transparent \"red\" object is red because green and blue light get eaten more than red, while red passes through more than red or green. Now, infrared and radio are also just different \"colors\" of light that we can't see; think of a radio antenna or a WiFi receiver as a kind of \"eye\" that can see those colors, while a transmitter is like a \"lightbulb\" that blinks in those colors. Walls happen to be \"transparent\" to radio even though they're \"solid\" to visible colors, just like a stained glass window is \"transparent\" to some colors and \"solid\" to others.",
"Similar to how visible light goes through glass, they are transparent in those wavelengths.",
"Without getting too in the weeds, electromagnetic waves aren't always bothered by solid surfaces. Take light for example....it doesn't go through traditional walls...but it does travel very freely through glass, another solid surface. WiFi/Bluetooth/other ranges of electromagnetic waves are able to travel through what we call walls (solid surfaces that light can't even pass through), similar to how light travels through glass. Another example is infrared. The infrared wavelengths that most thermal cameras detect are blocked by most glass, but other (shorter) wavelengths of infrared, such as from sunlight or most infrared heat lamps, passes through most glass....and coatings can be added to help block it.",
"I think a good analogy would be standing outside a nightclub. You only hear the bass (low freq sound waves) while most higher freq sound is either absorbed by the walls or bounced back.",
"Matter is 99%+ empty space, so some electromagnetic waves can freely travel through those spaces. Light cannot travel through walls because its wavelength is \\~500nm, meaning it travels back and forth billions of times before passing through and the wall absorbs most of the energy. Wifi, Bluetooth have longer wavelengths so they can pass through more easily.",
"Everything is made of stuff (even air) called atoms. Every atom is basically surrounded by electrons. Electromagnetic waves can go through some things and not others because of how the electrons are arranged in the stuff and how they interact with each other. Something that is not transparent for one portion of the electromagnetic spectrum may be transparent for another part. Whenever an electromagnetic wave moves from one material to another, it will bend a little bit as it travels forward or it might just bounce back in the direction it came from. When it can just travel through, that stuff is transparent for that particular electromagnetic wave. For radio waves and others like it, walls are see-through (like glass is for optical waves).",
"Sorry to tell you OP and anyone reading this thread, but nearly every answer is, while technically correct, wrong per your question. Wifi and other radio waves used for communications don't pass through solid objects (other than glass) appreciably and with the signal intact. So, how does wifi get all around your house? Typically by going through cracks around doors, and going out the windows of the room the router is in an bouncing off your neighbor's walls or nearby hill and trees and going back in other windows. Which is why it doesn't propagate all around a house very well, even a small house, and why it propagates better in cities and dense suburbs better than rural areas.",
"I asked the same question on here about a month ago, check it out for a lot of great, in-depth, answers - > URL_0",
"There are two things to consider when thinking about the electromagnetic spectrum which are frequency and energy. The combination of the amount/strength/level of these two is what determines how it can pass through \"walls\". Let's leave the characteristics of matter and other solid objects for now and imagine the world is made up of one type of \"wall\". Are you familiar with Non-Newtonian fluids? The best example are those made with flour and water, and when you slowly put your hand in, it goes though. But when you punch it, it becomes dense and hard (and possibly painful for your hand). These fluids are fascinating but we will not discuss its properties further (there are many simple experiments in the internet you can do at home). So in summary, slow means soft, fast means hard. Now imagine you have like a barrel full of that thing and you dip your hand in it for absolutely no reason, then pull it back. Then you repeat the process (slowly in, slowly out, etc.). One thing you will observe is that its easy doing it. You can put your hand in and pull it out smoothly and with ease (aside from your hand being dirty now with the flour lol). Now imagine doing it again, the in-out thing, but do it faster. This time it becomes more difficult as it requires more effort because the fluid becomes more dense. Now, how fast your hand dips in and pulls out is the frequency. And in general, the higher the frequency, the lesser it is likely to pass through \"walls\". But wait, how about X-rays and Gamma rays and the others. Well, that's where energy comes in. Continuing the analogy, if the frequency is fast you dip your hand on that magical fluid, then energy is the literal energy you exert to dip more than just your hand, say, like, your whole arm. Hence, the deeper your hand or arm goes in that barrel we talked about, the higher the possibility it will pass through \"walls\". With this in mind, if you dip you hand slowly but put your hand as deep as it can go, then you can say you can pass through \"walls\". But if you have high frequency where you dip your arm as fast as you can, you won't be able to pass through unless you push and pull your arm through with all your might. In the case of Wifi and bluetooth, well it has enough energy to pass through household walls. Unless your walls are made of lead, that's a problem. Of course, there are other factors such as what type of object the \"wall\" is, how thick it is, its chemical composition and the likes. The electromagnetic spectrum has also many other different properties to consider.",
"The first thing is: what is a solid object? Say I grab two atoms of a very solid material, say Iron. Is it a solid object? Well an atom is made of a nucleus of protons and neutrons, and electrons floating around. We consider that the space that the electrons travel around is the \"shell\" or the shape of the atom. But here's the thing: it's [almost all empty space]( URL_0 ). And when I say \"almost all\" I mean, the space that the electrons, protons and neutrons take is like 0.00..01% of the space that is the atom. What is happening there? Well lets look closer. Lets look at just an electron. An electron isn't solid (after all they can travel through solid copper wires). So I could put two electrons in the same space and they would both \"fit\" as they're not taking up space. *BUT* they wouldn't want to stay together. Electrons have negative charge, and charges of the same kind repel each other. So both electrons would want to be far away from each other. Atoms have electrons on the outside, and they each push each other away. So when you put your hand on a wall, the electrons on the shells of the atoms on your hand are pushing the electrons on the wall away, so you never mix. In an atom there's a nucleus with positive protons pulling the electrons enough that they can stay close to each other (they want to be as far as possible from other electrons, but as close as possible to the protons, so a compromise is reached). Sometimes shells have \"holes\" were another electron could pull in and then it'd be close enough to the positive nucleus to stay together. When this happens you get molecules, and that's how chemistry works. I won't go deeper into this, we don't need this for the question. So solid matter is really just atoms with electron shells that don't let other atoms pass through. But electromagnetic waves aren't atoms. They are something else, a photon, which is much much much smaller than atoms, and they can easily slip through the spaces between atoms, and between the electrons and atomic nucleus. Now if you remember waves go up and down very quickly. Depending on how fast they go up and down, they can have a high chance of hitting an atom, or could move through the spaces easily. When they go through all the spaces, most waves make it through the other side, some get bad luck and hit some random part and then get \"absorbed\". Others, instead, go up and down so quickly they are bound to hit at least one of the electrons (well pass \"close enough\" in theory) and when they do they kind of \"hit\" the electron and move it around (really the electromagnetic force of both the wave and the electron itself interact). When that happens it can't absorb the energy, instead it converts it to something else. It can be by releasing another electromagnetic wave, or it can be by heating up. Or doing all sorts of crazy stuff. There's whole fields of science dedicated to this. So this is why 5ghz and 2.4ghz can go differently through different things. Different atomic structures and different wave structures interact differently, but some just go through fully. It's also what affects how objects show certain color under certain light. See the colors we see are due to our observing electromagnetic waves, like wifi or such, that happen to be in a range. So when light of a certain color hits something, light of another color may appear. Sometimes it's not visible. Sun-blocker cream appears to become transparent to us, but absorbs UV light (so it's kind of black on that wave, we just can't see it). Similarly glass will let most visible light too, but it will bounce infrared away (so it appears \"white\" on infrared ranges, but we can't see it). What is really happening is that somethings will transform electromagnetic frequencies on a certain range (measured in hz) into something else (which is absorbing), other things will instead bounce it back (reflection) and some will just have it pass through (which is transparent objects). If you could see on the frequencies wi-fi works, a lot of walls would appear transparent. --- TL;DR: it's because walls or such are not really \"solid\", they simply push us back due to the electromagnetic force of the electrons in our atoms and the atoms of the wall. Waves don't care for that, so things aren't \"solid or passable\" to waves, instead things can either let waves pass through without any effect, alter the path of the wave (reflection and refraction) or consume energy from the wave to transform it into something else (absorbing)."
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l47qk7
|
Why do corporate inversions work? Why wouldn’t all corporate entities be taxed on profits they make inside a country regardless of where they are headquartered?
|
I’m just curious how/why it matters where a company is headquartered. Is it because we want to tax a corporation for profits made in the rest of the world and we are willing to accept a Lower tax rate to incentivize them to headquarter here, or is there a world trade competition issue that would result in a trade war if we basically said in order to have access to the country’s marketplace you have to pay x tax rate on all profits made in this marketplace?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gkmus7y"
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"text": [
"Because they often present minimal profits. One example of a very famous coffee brand: they pay royalty fees for their products to a third company, based in a tax haven, leaving their physical stores with zero or minimal profits for taxation."
],
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5
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|
[
"url"
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[
"url"
] |
l487ah
|
what is the money based on? What makes the dollar valuable?
|
Economics
|
explainlikeimfive
|
{
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"gkmxfzn",
"gkmy23b"
],
"text": [
"The US dollar used to be based on gold. Hence the term \"gold-standard\". Every dollar you had could be traded into a bank for a certain amount of gold. That's not really the case anymore and now it's really just based off of the faith of the consumer. I'm not an economics expert or anything, but this is my understanding.",
"It's essentially a social acceptance that gives it value. If you've ever read lord of the flies, here's a connection to that book. The boys on the island use the conch to keep order. Whoever holds the conch, holds the ability to speak. The conch is not magical, threatening any of their lives, or even special- it's just a conch.. however. The boys have socially accepted it having value for the sake of order... the same is true with money and all forms of currency."
],
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11,
7
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|
[
"url"
] |
[
"url"
] |
|
l48ilr
|
How do bird legs work?
|
They look so thin and basic. How do they function?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkn064f",
"gknsmcf",
"gknrtam"
],
"text": [
"Like human fingers, there are no muscle groups in them, just tendons. By relaxing or constricting the tendons, they move their joints, just like we move our fingers and toes. Interestingly, some birds can wrap their claws around a branch and then relax. When they rest, their body weight can push down on the legs, and exert force on the tendons, which causes the tendons to reach their maximum length of stretch, and force the claws to squeeze around the branch.",
"It’s worth noting that bird bones are hollow. Birds don’t weigh much so their legs are not necessarily supporting the weight it might look like.",
"If you mean 'why does a flamingo's knees bend backward' sort of thing, it's because the part you see bend backwards is the ankle, not the knee. [this diagram]( URL_0 ) shows it pretty well."
],
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80,
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|
[
"url"
] |
[
"url"
] |
l48m6u
|
why can you fall asleep so well in cars?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkn81aw"
],
"text": [
"They're warm, comfortable, enclosed spaces. Watching the road or the scenery go by is very relaxing. The sound of the engine, the tyres on the road, and the airflow over the chassis is sleep inducing, supposedly because it reminds us of the sound we heard in the womb before we were born."
],
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10
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
|
l49lsm
|
- What do blood thinners actually do?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkn6m7u"
],
"text": [
"They can do one of two things: Anticoagulant drugs, like warfarin, slow down the processes by which the body makes clots. Anti-platelet drugs, like aspirin, stop your platelets from clumping together to form the clot."
],
"score": [
17
],
"text_urls": [
[]
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|
[
"url"
] |
[
"url"
] |
|
l4a496
|
Why are currencies worth different amounts and why do they fluctuate?
|
Economics
|
explainlikeimfive
|
{
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"text": [
"Cost of living varies globally. The costs of doing business, and the availability of resources and people vary, too. The rest is because there are markets, where people make offers and agree to variant prices. We have enough jelly beans, so the price goes down. We need more pinatas, so the price goes up.",
"The reality is very complex and includes effects from capital flows, trade, purchasing power parity etc. and no model has yet succeeded in fully explaining (and modeling) the development in the long-term, because the process simply has too many variables. Essentially it boils down to each country (or monetary union) emits it's own currency. To purchase goods from or in that region you must pay using that currency. This creates demand and supply for currencies due to crossborder transactions. For example, a German company purchases goods in the US and must pay in Dollars, so the German company must first acquire Dollars or the American company accepts Euros but must then at least partly exchange that for Dollars to pay taxes in the US, wages, etc., essentially \"producing\" Euros and \"consuming\" dollars in the exchange process. This is very simplistic, but the sum of all transactions essentially ends up creating demand and supply for currencies on the foreign exchange market, the equilibrium of which creates the relative prices or exchange rates.",
"Floating currencies are a natural consequence of \"fiat money\", or currencies whose value isn't fixed to a specific other good (classically, precious metals like gold or silver, referred to as 'specie'). But here's the crazy thing: specie-backed currency fluctuates too, it just fluctuates in tandem with whatever metal it's pegged to. This is what happened to the Spanish Empire after they discovered the new World. They brought back so much silver and gold from their American colonies that the influx sharply devaluated them. So, the question then becomes, if you don't want to peg the price of your currency to gold, why not peg it to the price of another currency? Some countries do this, usually smaller ones, and that has advantages and disadvantages. The advantage is that you benefit from stability, if you're pegged to a stable currency. The disadvantage is that you lose control of your country's monetary policy. So, what's monetary policy? Monetary policy is a way governments and the central banks they appoint can manipulate their currency to try and stimulate economic growth, or curb inflation. If your economy suffers from persistently low employment, and wage growth is low, the central bank can devalue the currency to make money more available to people with credit, which, *in theory*, will spur investment, make your exports cheaper, and lead to more jobs. If your economy has high employment and rapid wage-growth, however, the price of basic goods like food, fuel, etc., can rise rapidly, and then the central bank can appreciate the currency (cause it to get more expensive), deterring investment, making exports more expensive, and tightening the job market. Politically, there is always a tension between the people who want the currency to inflate, and the people who want it to appreciate, particularly, exporters, importers, and above all, **BANKS**. A bank loan, is, in part, a bet that over the term of the loan, the currency that the loan is denominated in won't deflate sharply. Let's say you borrowed $300,000 to buy a house at 4% APR, for a 20 year term20. If the value of the currency stays the same (zero inflation), the real cost of that loan will be ~$436,300. If the value of the currency drops by 25 per year (which is the declared inflation target of most Western countries), the effective rate of interest on the loan drops to 2%, and the real cost of the loan will be ~364,000 in inflation-adjusted dollars. So, you see how a very slight change in inflation wildly changes the realized profits taken by the bank from their borrowers. So, as a general rule, lenders and importers want low inflation, borrowers and exporters want high inflation. Anyone with fixed expenses wins with high inflation, and anyone with fixed income wins with low inflation. And in any given country, these different political actors may win or lose the monetary policy battle at any given time.",
"this question has been asked a ton already. here: [ URL_1 ]( URL_0 )",
"Redhouse works by paying with redbucks. Bluehouse works by paying with bluebucks. You get the idea. Redhouse makes very cool stuff, such as cool cars, cool gadgets, cool phones etc. so everyone wants to get redbucks. Redbucks are very valuable. Bluehouse grows vegetables and maybe mines some mineral. Bluebucks are not as valuable for everyone in the neighborhood but ya know people still desire it to get vegetables and copper and such. Yellowhouse has conflict. They are unable to produce much so nobody desires to get yellowbucks, making yellowbucks very worthless. Purplehouse mostly produces oil. Purplehouse is very rich and everyone wants purplebucks. However electric cars are overtaking, so each time purplebucks are becoming less desirable, and are losing worth. Oversimplified explanation, but you get the idea.",
"The truth? People don't really know. There are definitely guesses which use things like how much of different goods are traded from different countries, how much people are willing to pay for those goods, etc. But honestly, no economist can in good faith tell you exactly why a small shift in the euro/dollar ratio happened.",
"In 1944, the Allied powers held a conference at Bretton Woods in New Hampshire. There, they set the price of gold as $35 US. Other currencies were 'pegged' to the US dollar, within narrow bands. This provided relatively low inflation from 1945-1971 (~2% a year) when Europe was growing rapidly as it recovered from WWII, and the US was creating the first TV economy. The easiest way to think of this is gold provided an 'anchor' to prices. Since an ounce of gold was the same anywhere in the world, and the demand for it was universal, it became the global standard for value and the US dollar became a de facto stand-in for it. Hence the phrase \"The dollar is as good as gold\". Trying to explain the Eurodollar explosion is beyond ELI5. Let's just say banks beyond the Fed's control in Europe created more dollars than Fed policy wanted. At some point, it became clear that to everyone that there were many more US $ out in the world than there was gold in Ft. Knox to redeem it. This was ignored in that generation's version of *The Emperor's New Clothes*. The only guy who wouldn't play along was France's Charles De Gaulle, who inconveniently kept asking Nixon to redeem France's US$ for gold. This could not be done; frostiness ensued. In 1971, that play's run ended. In the history of finance, the term is \"the gold window\" was closed, and the price of gold was no longer tied to the US$. The price of gold went up, slowly at first, and then exploding to $800 by 1980. The anchor was gone, and inflation went crazy as there was no standard to tie prices to. Prices doubled in ten years compared to the 34 years they took to double from '46 to '70. Everything we've done since is to try to find some replacement for gold as that monetary anchor. The Euro was an attempt to do that; not working too well, IMHO. Macroeconomics is both complicated and fraught with religious wars, so I'm not going any further here."
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|
[
"url"
] |
[
"url"
] |
|
l4ccff
|
How do people gain access and leak CCTV videos?
|
I go on 4chan a lot and see threads of gore and "rekt" and continuously find myself wondering, "where do they get these videos? Who is giving these people tapes of random maimings and such?" I know that they probably **find** the video on liveleak or some other gore site but how does the footage itself make it on the internet? Edit: Why the downvotes?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gknpnje"
],
"text": [
"Someone who has access to the source files initially leaks them. It's really that simple. There's also a chance, if the CCTV system is networked, that it is compromised and hackers go through the files for a bit of fun and come across it. Then *they* leak it."
],
"score": [
4
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
l4ci5y
|
. How do websites like ‘Ancestry’ and ‘23 & me’ work?
|
I am not sure if it is the altered state I am in, but I can’t seem to understand how these websites are able to track back so far before DNA could be analyzed and understood or even known?!
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkntba8",
"gknszdp"
],
"text": [
"They compare your DNA to the DNA of modern people in other regions. Their equipment is meant to search for certain common markers with other groups. So let’s say they take your DNA and run it through their database. They find that your DNA is most similar to people who live in southern Italy and you also have some similarities with Hungarians. Your results come back mostly Italian and partially Hungarian.",
"Well Ancestry uses reports, like birth certificates, things in the news, etc. 23 & me goes off of the genomes in your DNA, which some are specific to regions of the world/ethnicities, and my looking at the placements and mixtures, they do the path. It’s not perfect, as there have been cases of identical twins getting different results. And to know the timeline of DNA they’ve gotten samples from bones/fossils/preserved stuff from that time."
],
"score": [
15,
9
],
"text_urls": [
[],
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|
[
"url"
] |
[
"url"
] |
l4ctl3
|
how does an impulse travel from one neuron to another
|
Biology
|
explainlikeimfive
|
{
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"gknw78u",
"gknus7b",
"gkoib2r"
],
"text": [
"When an impulse reaches the end of a neurone (the axon) it releases a neurotransmitter. This is a chemical that carries the message to the next neurone that stimulates it to activation. It’s travels by diffusion but this happens very quickly.",
"I didn't learn my theory in English but basically, each neurons has a -70 mV voltage at rest, when a stimulus happen, it activates ion pumps that pushes in and out of the neuron ions K + and Cl- and if the the voltage get to -50 mV or above, the neuron get activated automatically creating an even higher voltage by activating even more ions pumps, this higher voltage will create a wave activating every other neurons connected to the neuron that initiated the wave until it reach a neuron that will stop the wave.",
"So, at the end of a neuron, these branches are present which we call axon terminals. There is a short gap present in between these branches of 1 neuron and the second neuron. When the impulse reaches the branches of 1 neuron, it stimulates the end part of the first neuron and makes it release certain chemicals which we call neurotransmitters (the most common of which is AcetylCholine or ACh) These Neurotransmitters travel the short distance (which is known as synapse) between the first neuron and the second neuron. After travelling, they bind to, or you can say, stick to the membrane of the second neuron, thus carrying the impulse. & #x200B; There are other ways as to how an impulse travels from 1 neuron to other, but this is the most common way and the preferred way of our body"
],
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6,
3
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|
[
"url"
] |
[
"url"
] |
|
l4d7d6
|
why is it that only one side of the moon is visible from earth? If both the earth and the moon rotate then why do not we see the other side?
|
Earth Science
|
explainlikeimfive
|
{
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"gknvdxi",
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],
"text": [
"The moon is tidally locked, meaning that it rotates at the same rate that it orbits the Earth. If you imagine a point on the Moon's surface directly facing the Earth, the Moon rotates at such a speed that that point continues to face the Earth throughout its orbit. This is a typical fate for moons throughout the Solar System, especially those close to their planets. In some cases, the relationship is even two-way: Pluto and its largest moon Charon are *both* synced up to Charon's orbital period, so you can only see one side of Charon from one side of Pluto (and the other side of each never sees the other). If the Earth survived long enough, the Earth would sync to the Moon and the \"day\" and \"month\" would have the same length - but Earth probably won't survive long enough for this to happen, as our planet is ultimately doomed when the Sun expands at the end of its life. The match actually isn't quite perfect because the Moon's orbit isn't quite a circle. So the rotation gets a little bit ahead/behind the orbit as it goes before ending up back in sync at the end of each orbit. So you can see a little bit more than half the Moon over time. But it's only a bit more than half.",
"The moon rotates around its axis, but it's also orbiting around Earth. Imagine swinging a ball on a string around you, yes the ball is spinning once every time it goes around you, but the same side is still facing you. Though instead of a string keeping it from rotating, the rotation that used to be present was slowly turned into heat by tidal forces. It isn't perfect, there is some wobble, which is called libration.",
"The moon has been with us for quite awhile now, and as a result it has really let itself go. As it goes around the earth it kinda turns just right so we can never quite get a direct view from behind, as it is a little embarrassed that it’s dark side is not quite what it used to be when we first met."
],
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5,
3
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|
[
"url"
] |
[
"url"
] |
|
l4dlbt
|
what happens if I connect my power bank to itself? Will it explode??
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gknwsdv",
"gkny88c"
],
"text": [
"Many power banks will disable the outputs when connected to a power source, but otherwise the entire contents of the battery would slowly be lost to heat as it attempts to charge itself from its own batteries.",
"No, unless it's very poorly designed. It will slowly discharge itself. It's not some sort of power increasing perpetual motion machine."
],
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10
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|
[
"url"
] |
[
"url"
] |
|
l4e0vq
|
why are octopuses so intelligent when squids and most other cephalopods aren't?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkod1nc"
],
"text": [
"Why are humans so intelligent when Lemurs and Vervet monkeys aren't? Intelligence (and specifically, intelligence that humans recognize) is just one trait among many that can change as needed by evolution. Octopi have been their own line for at least 300 million years, which is PLENTY of time to evolve a brain that can do things a squid's brain doesn't need to do."
],
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11
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|
[
"url"
] |
[
"url"
] |
|
l4e16g
|
Why do you feel heat immediately when you touch some hot things, like a pot, but you feel others gradually, like a cup of coffee?
|
Physics
|
explainlikeimfive
|
{
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],
"text": [
"If mostly has to do with the material. Most metals will gain heat quickly, but it will also transfer that heat quickly. The ceramics or plastics of most mugs will gain heat slowly and transfer it just as slowly. In physics this is known as a material's specific heat capacity. It is the measure of energy it takes to raise a gram of that substance 1°c. Metals have a low specific heat. Ceramics have a higher specific heat.",
"Contrary to the top comment, this has very little to do with heat capacity. A minimum amount of heat capacity is required to feel the heat, but it has nothing to do with how fast you feel that heat. This is caused by thermal conductivity which is the rate at which heat transfers when two surfaces are in contact. The value you want to look up if you compare two different materials is the coefficient of thermal conductivity. A higher value will transfer heat faster when in direct contact."
],
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3
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|
[
"url"
] |
[
"url"
] |
|
l4e2s4
|
why do those dark rings under your eyes form? even with proper sleep, diet and exercise?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gko1r0m"
],
"text": [
"Has to do with blood pooling in the skin underneath your eyes. Could be genetic, staring at screens also can cause it, plus it just happens naturally with age and sun exposure. Even slight differences in sleep patterns can trigger it. It’s not really an indicator of anything, and most people have them, it’s just a weird physical quirk"
],
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|
[
"url"
] |
[
"url"
] |
|
l4eccc
|
Why you can’t put some dishes in the dishwasher
|
My spouses mugs have a warning to only hand wash them. Why is this? I assume it has to do with how dish soap vs dishwasher soap interacts with various kinds of dishes?
|
Chemistry
|
explainlikeimfive
|
{
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"text": [
"From my experience some dishes should only be hand washed because the heat of the dishwasher can chip the paint. I had a wonder woman mug and when it got washed a lot of the sealant came off. Plastic bottles will melt and deform under high heats too",
"It has to do with the heat. Some dishes will say \"top rack only\" and some will say not dishwasher safe. A dishwasher gets VERY hot inside during the drying process. That can melt, crack, or otherwise damage some fragile stuff. Some stuff, like I said, can be ok on the top rack because it's further away from the heating element. Some stuff is still too fragile though.",
"The heat can warp or crack some materials and the detergent can etch things badly. I am careless about dishwasher protocol and my wineglasses are all fogged up.",
"I’ve cracked several plastic cups because they couldn’t take the heat from the dishwasher. Same with the designs painted on some of them. They chip and fall off. I still do it lol",
"Are they the vacuum (double walled) insulated ones? Those can crack if they’re put under very high temperatures (dishwashers are much hotter than the stuff from the sink), I think because of the vacuum inside. If they’re heated up to much, the metal will expand which can interact with the vacuum and cause it to burst. At least that’s my understanding. A physics expert might be able to explain more.",
"Some metals will corrode. Some paints and laminates may get destroyed. I put a silver cake server in (wedding cake server) and apparently it had a coating that prevented oxidation. That coating half came off in the dishwasher. And yes. The soap makes a difference too. Dish soap is more like soap. Dishwasher detergent is a chemical cleaner and is much stronger. It has to be because it has to do its work mostly by itself without you scrubbing it."
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[
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[
"url"
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l4ejct
|
How do we know there isn't a final number for pi, but that it goes on forever?
|
So apparently it goes on forever because it's irrational. So next question, *how** do we know pi is irrational?
|
Mathematics
|
explainlikeimfive
|
{
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],
"text": [
"At the most basic level, the most common way to prove a number is irrational is to first assume that it's actually rational (i.e. can be written as a/b where *a* and *b* are both whole numbers) but show that this assumption leads directly to a contradiction (e.g. 0 = 4 or similar). As for the specifics to pi, there's several different proofs that pi is irrational, but unless you're quite familiar with university-level math (calculus and beyond), they're neither easy to understand nor intuitive. Here is one such proof by [Timothy W. Jones of the University of Washington]( URL_2 ). That said, I believe Lambert was the first person to prove pi is irrational, in 1761. Essentially, he showed that: * tan(x) = x / (1 - x^(2) / [3 - x^(2) / (5 - x^(2) / [7 - ...])]) where tan(x) is [the tangent function]( URL_0 ) which you might remember from geometry classes in middle school or high school. Basically, the above expression is a continued fraction. It may be difficult to parse out in-line like that, but it should look [something like this]( URL_1 ). Lambert also proved in a separate result (unfortunately I don't think I can really ELI5 this part) that if *x* is any non-zero rational number then the above expression is irrational. If we assume that pi is rational then it follows that pi/4 must be rational as well. However, tan(pi/4) = 1 and 1 is not irrational, so we've reached a contradiction and thus we know our assumption is false."
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"https://www.mathsisfun.com/definitions/tangent-function-.html",
"https://i.imgur.com/hSrmZS2.png",
"http://faculty.washington.edu/rvanderp/Teaching/Archives/308Fall_10/Example2.pdf"
]
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|
[
"url"
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[
"url"
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l4fl0g
|
why do we need to keep eating iron or foods with iron? What happens to the iron we've already eaten? What happens to the iron in the next meal we eat? Can our bodies recycle the iron in our blood or not? Why?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkoa2l8"
],
"text": [
"Disclaimer: not a medical expert. I'm pulling most of this from [this minuteearth video.]( URL_0 ) Iron is used to make red blood cells, which carry oxygen. Your body needs a LOT of red blood cells, and unfortunately they are treated as more or less disposable, being produced and then retired a few months later. Iron is recycled to an extent; your body breaks down the red blood cells it retires and harvests their iron. But not all of this iron makes it back, so you need to eat more to replenish the amount you lose. And you need lots of iron. Your body produces millions of red blood cellsper day, so even the iron reclaimed from retiring red blood cells doesn't quite cut it. You need to eat iron to make up the difference."
],
"score": [
8
],
"text_urls": [
[
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]
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}
|
[
"url"
] |
[
"url"
] |
|
l4fo79
|
Why are antibiotics prescribed for a course of ten days to two weeks as opposed to a shorter treatment, especially for minor infections?
|
All I've seen in a sub search is explanations of how they work, without length of treatment being directly addressed. Anything else I'm given to treat acute issues is a one dose deal. Bonus points if you can also ELI5 why antibiotics are always ginormous horse pills.
|
Biology
|
explainlikeimfive
|
{
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],
"text": [
"A smaller dose of antibiotics will generally get the initial infection under control. But it won't kill *every* bacteria, which is a bad thing. The survivors tend to be more resistant to the antibiotic than the bacteria that are killed. The more this happens, the less antibiotics work overall (because more and more of the wild bacterial population becomes resistant), so it is **extremely important** to finish a course even if your symptoms clear up. I don't know the answer to your second question, but my guess would be that it's because antibiotics usually have to chemically poison the bacteria directly. So you need enough for the concentration of the antibiotic to be high enough throughout the infected areas to kill bacteria effectively. Normal medications are mostly signaling molecules that don't so much *make* your body do something as *tell* is what to do, and that doesn't take too much. That'd be my best guess.",
"Bacteria reproduce quickly so if you don’t kill enough of them they grow back. Even worse they may grow back immune to the antibiotic you took. You have to take them for that long to make sure they are dead and don’t come back. I was exposed to tb once and had to take an antibiotic for six months.",
"This is not always the case. I’m allergic to penicillin, so I am often prescribed Zithromax for sinus/respiratory infections (that I’m prone to getting). It is a 5-day blister pack of pills.",
"From experience: the doses are prolonged in an attempt to make sure whatever bacteria infection you may have is completely gone. After the initial 2 days of doses you might feel all better but some micro clusters mightve survived the bombardment enough to regroup and restart the infection. So the extra days of doses are there to try and get rid of the bacteria in question down to a very small amount for your immune system to finish it off or rid of it completely. And some pills are huge mainly because they are designed for slow release or to get far enough into your digestive system before releasing for maximum absorption.",
"The human body has a huge amount of bacteria in it, and these bacteria perform all kinds of important functions in the body. They're basically symbionts with us and if they weren't there we'd have significant health problems. Then when you have an infection and need antibiotics, it's because you have a bad bacteria overgrowth in your body. So the antibiotics kill the bad bacteria but they also kill the good bacteria that you need. Doctors need to prescribe enough antibiotics to kill the bad bacteria but not enough to kill the good bacteria. They could give you a massive dose of antibiotics on day one that kills all of the bad bacteria but also kills all of the good bacteria. That's not a good idea. Instead, they give you a small dose daily for a period of time that will kill off the bad bacteria but hopefully the good bacteria is different enough from the bad bacteria that the antibiotics don't kill it all off, too. They run all kinds of clinical trials to get this mix right. They've come up with bacteria courses that last 5 days to 2 weeks, usually, for this purpose. They need a general length that will apply to the most people. Might a person with a minor infection do fine with 3 days of antibiotics rather than 2 weeks? Possibly. But they can't run a study on every single person. They have to get a general plan for everybody. And they can't risk too short or too weak of a treatment due to the possibility of antibiotic resistance discussed by others here. And they can't risk too long or too strong of a treatment due to the possibility of killing off your good bacteria and causing health problems in that direction. So they have a happy medium to hopefully treat the most people the most effectively."
],
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8,
6,
3,
3,
3
],
"text_urls": [
[],
[],
[],
[],
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|
[
"url"
] |
[
"url"
] |
l4g3qo
|
Goosebumps!
|
Hi! Why do we even get goosebumps? I've been having it alot back and forth during the past couple of months quite regularly, without any specific reason. So I am wondering why we are getting it, what triggers it, is it bad or good and is there something you can do to prevent it? Thankful for all kinds of responses or theories. Ps. You guys are awesome.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkocjcp"
],
"text": [
"The bumps are tiny contracted muscles to fluff out your fur so that it holds more warm air to prevent you from getting too cold or to make you look bigger if you feel threatened or nervous. Evolution just hasn't caught up with the fact that you don't have fur that works like that anymore but still have the muscles."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4gorz
|
How do polarized sunglasses work?
|
I get that they dull down reflections and things, but how do they do that? I also noticed that if I'm looking at a screen (phone, computer, etc...) it creates a rainbow effect, and if I look at the screen sideways, it looks extremely dark.
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkogb2f",
"gkoh6t5"
],
"text": [
"Light from the sun gets polarized when it bounces off of something. When it is polarized, it is very \"organized\" in a certain way. Because of how organized it is, it is possible to stop that polarized light from going through lenses that are polarized differently from the way the light was polarized. Kind of like how the square shape can't fit through the round hole. Light from the sun that is un polarized is kinda like silly string and goes through the round hole easily. Light from most screens now a days go through a polarizing filter to organize the light and so when you look at the screen through glasses, there is some compounding effect of the two polarizing filters (screen and lenses) The physics gets pretty complicated but I hope that made some sense.",
"So light has polarization. It’s super confusing. Basically, each individual light photon moves like a straight shot. But in that straight shot, it has an angle around that straight line that it’s polarized to. Much like how an airplane moves in a straight line in 3d space, but it’s wings are wide in one direction. Polarizing lenses work by creating long, narrow, microscopic slits that only let light through that’s polarized in that direction. And it blocks most of everything else. In the plane example, it’s like if you had a horizontal slit large enough for the plane to get through, but only if it’s wings are exactly flat. If the plane’s tilted at all, the edges of that slot will tear off some of the wing. If the plane is tilted 90degrees, it’s wings are torn off entirely. So back to polarized lenses. When they’re used to dull down reflections, it’s because they reduce the amount of light that’s coming in at weird angles. For many electronic screens, it’s because the light from the screen is already polarized; if you rotate the screen or your head 90 degrees, you’ll either see it’s full brightness, or no brightness at all. If it passed through the set of slits on the screen, all the light’s in one polarized direction as all the other light was blocked; if the slits in your lens are the same direction, you’ll see fine, but if it’s 90 degrees off, then almost all the light will be blocked. In the case of rainbow-y glass like in modern cars, it’s usually because it has a lightly polarizing screen on it already."
],
"score": [
8,
7
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
l4h1bw
|
Why does rust and aluminum burn so well together?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gkohizl",
"gkohnp6"
],
"text": [
"If the rust (=oxidized iron) and aluminum are powdered and well mixed and you have something that can be used to ignite it, such as a strip of magnesium, a reaction will start that gets very, very hot. Aluminum has a higher affinity for oxygen than iron does and with the available energy it can grab the oxygen atoms from the rusted iron. The result is aluminum oxide and molten iron.",
"Thermite requires a lot of activation energy to get started burning but the rust acts as an oxidizer for the aluminum producing aluminum oxide and iron as a byproduct plus a ton of heat. aluminothermic reaction"
],
"score": [
5,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4haqh
|
How does a company gain when their stock prices go up?
|
For example if market opens with a 20% gain in a company's stock, there is a lot of noise happening. But what does this mean for the company? How exactly did the company benefit from this spike? Its not that the founders can sell their shares tonight. They can't pay their suppliers in equity either, so what does a spike really mean for a company , if anything at all?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkoivjg"
],
"text": [
"In short the price price only affects the company itself if it sells new shares to the market. The people on the board who make the decisions own significant amounts of that companies stock. The individual share holder on the board is who benefits not the company itself. And keep in mind the price doesn't always reflect the state of the company just look at GME or tesla shares."
],
"score": [
4
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4hhew
|
Why are some diseases and conditions easy to cure, while some, like cancer and psoriasis, are so impossible to cure that they’re deemed "incurable"?
|
Basically why can we cure some things and not others?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkok1pl",
"gkolvvr"
],
"text": [
"Because they’re caused by different things. Cancer is part of your own body losing control and growing wild. It’s very hard to effectively target that, because they are 99.99% the same as healthy cells. Something like a bacterial infection is (relatively) easy to treat because it’s easy to differentiate between bacteria and your own cells. We have developed tools (antibiotics) that can use that difference, poisoning the bacteria while leaving you (mostly) healthy.",
"Because \"disease\" and \"condition\" are *phenomenally* vague terms that cover anything from not quite enough of a particular kind of bacteria in your intestines causing you to get a little bit of gas when you drink a lot of milk to giant steel pole rammed through your skull. And that's less of an exaggeration than you might think, too. Diseases and conditions are all caused by something. Conditions that are easy to cure tend to be ones that are caused by bacteria or viruses. These are easy to cure because our body cures them automatically: Get a bacterial infection and eventually your immune system will figure out the best way to destroy them and then do that, so pharmaceutical cures tend to just be things that prepare the immune system in advance (vaccination) or cripple the bacteria, making them easier to fight (antibiotics). Since bacteria are living cells, anything that kills a cell will kill a bacteria, and there are lots of things that do that. Just need to find one that kills bacteria and not us. Unfortunately, bacteria reproduce so quickly that they are evolving resistance to antibiotics right now and we are fast approaching a future in which bacterial infections are really quite difficult to treat cos they're resistant to all our bacteria death chemicals. Conditions that are difficult to cure tend to be ones that do direct and permanent damage to physical structures - ones that destroy important cells that our bodies aren't able to grow replacements for. Many of these conditions are auto-immune conditions, which means they're the result of our own immune systems falsely detecting these cells as foreign and attacking them as they would attack foreign cells. Others that are difficult to cure can be ones where you can destroy 99.9% of the cause, but that can regenerate from just a tiny surviving part. This is what cancer does. Unless you get rid of *every* cancer cell, the tumour has a good chance of growing back. Difficult to cure conditions are often ones that the immune system doesn't respond to. For example, many brain disorders are incurable since the inside of the brain is a \"privileged\" area. Nothing is allowed inside, not even the immune system, so any dangerous thing that can infiltrate its way inside is going to be able to get up to all sorts of trouble without the immune system being able to do anything about it. Other disorders in this field are ones that the immune system doesn't realise is a threat - conditions they're either not programmed to be able to recognise at all or conditions that are capable of masking their own presence (normally foreign cells cover themselves in things called antigens which are kind of like big red stickers saying \"Hi I'm a terrorist!\", but some have the ability to do something like not wear the terrorist sticker, or wear a sticker saying \"Hi I'm *not* a terrorist!\" Malaria even climbs inside other cells which would be kind of like if I hollowed you out, stole your passport and wore your skin to get through security)."
],
"score": [
10,
5
],
"text_urls": [
[],
[]
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}
|
[
"url"
] |
[
"url"
] |
l4hvo6
|
If autism is mostly genetic, how come some severely autistic kids are born to completely neurotypical parents with no autism in their family.
|
I read in one of my genetics classes that autism is 90% genetic, which means that it has to be passed down somehow, yet I know plenty of neurotypical parents who have autistic children, some on the severe end of the spectrum. How does this come up seemingly out of nowhere?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkosytt",
"gkon00i"
],
"text": [
"Autism is thought to be caused or made probable by complex genetical constellations and not by a single gene. This increases the chance that no parent has the whole genetic constellation, but the child gets an \"unlucky\" combination. A simple example: The combination (A1, A1)+(B4, B2) causes autism. The mother carries (A1, A3) + (B1, B2) and the father (A1, A2) + (B3, B4). No parent has autism, but a child has a 1/16 chance of inheriting the unlucky combination. In the real world, the gene combinations are much more complicated, and recessive/dominant genes may play a role.",
"It is possible that one of the parents were just never diagnosed. I believe this is what happened with me. After my sons diagnosis and looking at him and his behaviors I feel that I am autistic also and was just never diagnosed because I was high functioning and learned through reading psychology books at a young age how people worked, who to deal with them, and how to function myself."
],
"score": [
10,
4
],
"text_urls": [
[],
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}
|
[
"url"
] |
[
"url"
] |
l4jjto
|
How and why 6gb, and 12gb RAM sizes came to be in smartphones?
|
With RAM sizes, I have seen them going up by doubling, for example 1- > 2- > 4- > 8 etc. So why and how some smartphones come with 6, or 12gb of RAM? Is there any specific reason for this "odd" amount of RAM?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkovsdh"
],
"text": [
"Memory in pcs always come in powers of two because of the architectural design. Ie dual channel, requires it to be even. And since the dimm dimensions are also strictly defined its just been convenient. For phone memory, the architecture is different so they could plop in whatever GBs they wanted since ram is soldered on and space is more important as well so they stick on the bare minimum they think they can get away with based on modern usage scenarios. In terms of memory controller design. Ram has a row and column address and the number of rows and columns is in powers of two (because binary) so making 6GB ram doesnt leave any unused addresses. But 5gb will."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4jlsk
|
What is a short squeeze in trading?
|
There is a lot of news right now about a historic “short squeeze” regarding GameStop. Can someone explain what is happening
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gkowajx"
],
"text": [
"There are a LOT of shorts on gamestop ticker GME. Shorts are stocks that are borrowed from a lender and then sold at a price and then bought back later and returned to the lender. if the stock goes down they make money (sold for $100 buy back for $90). but if it goes up they lose money (sold for $100 buy back for $110) So they hold on to the short until it goes down because gamestop is kind of a failing business and no one bets on a failing business, so it’s bound to go down right? The problem is a bunch of people on the internet decided to jump on a bandwagon and started to buy and hold a bunch of GME shares which means the price won’t go down. more people see this news and buy more which causes the price to go up. eventually the lenders feel like the shorts might lose too much money and won’t be able to return the shares they lent them and force them to cut their losses (sold at $100 but have to buy back at $150) this causes the stock price to go up. as long as the price goes up, the shorts will have to cut losses by buying shares, causing the stock to go up more. Thus short squeeze."
],
"score": [
36
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4k9hb
|
Universe's smallest time unit is planck time, how can real world have discrete time intervals, does that mean a photon is at the same place at half a planck time?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkowrqa",
"gkp2frq"
],
"text": [
"It isn't the smallest time unit. Time is not discrete at the Planck scale, and neither is space with regard to the Planck length. It's more like our physical models somewhat break down at that scale.",
"Our current understanding is that time isn't discrete. Pop science often talks about the Planck time as the smallest unit of time, but this isn't an accurate description of the science. There is nothing particularly special about the Planck time or Planck distance with regards to the nature of time/distance other than around that scale we expect that we would need a quantum theory of gravity to properly describe what happens on those scales."
],
"score": [
27,
9
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4kol7
|
what causes market elasticity?
|
I'm aware that market elasticity is how much a specific market is prone to changes in value, but what factor cause one market to be more or less elastic than another?
|
Economics
|
explainlikeimfive
|
{
"a_id": [
"gkp3pg2"
],
"text": [
"If the price of bananas doubles, a many people will simply decide to buy fewer bananas. But if the price of petrol doubles, there are a lot of people who just cannot buy less of it. They are dependent on their car if they want to keep their jobs. So in that case, the demand for petrol will only decrease a little. So, while there are certainly other factors, an important one is available alternatives. & #x200B; Note that there may be differences between short and long term elasticity. In the petrol example, if the price of petrol remains high for years or decades, many people will take that into consideration when they relocate the next time, maybe choosing inner city life with public transports over suburbia, and reducing demand for petrol in the long term."
],
"score": [
3
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4l3w3
|
Why does cold water taste better than hot water, even when it's freezing outside?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkp4th3",
"gkpdrza",
"gkp08ud",
"gkpmjio",
"gkpm8sm",
"gkp4e7s"
],
"text": [
"Because of evolution. In the wild, water that's been sitting stagnant is warm. Stagnant water is a breeding ground for bacteria and disease. Running water, say, from a stream or natural spring is usually cold. The colder it is, the closer to the source it is, and thus more fresh and clean it is. Evolutionarily, humans are drawn to cold water because it would have helped our ancestors survive better by avoiding waterborne diseases. Those that didn't have such a preference would have died out due to sickness, thus creating one of the necessary keys for a species to evolve.",
"Because that's what you like and what you're used to. I can't drink cold water. Locks my throat up. Like brain freeze in your throat. I love water. But once you put ice in it it's ruined",
"Water is not supposed to taste anything. What you are tasting is impurities in the water which generally taste bad. But when you drink cold drinks your taste budds gets dulled and is unable to taste them. This is why you drink cheap beer cold and expensive beer luke warm. And if you want to drink hot water when it is cold outside then you can add some flavoring to it.",
"I'm gonna throw some doubt on the evolutionary answer, because not all people in the world drink cold water as often as we do in, say, the US. It's cultural. Live in China for a while and you'll quickly get used to drinking hot water on occasion. It's just as nice and refreshing, though as a westerner it is, at first, a little strange. At this point I don't mind what temperature my water is served at, and hot can actually be nice on a cold day.",
"Because that's your personal preference. In Chinese culture cold water is considered unhealthy and disgusting. Nobody drinks it.",
"Evolutionary pressure. In nature, warm water usually means stale water which can mean death."
],
"score": [
121,
19,
10,
9,
5,
4
],
"text_urls": [
[],
[],
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|
[
"url"
] |
[
"url"
] |
|
l4lij1
|
why does getting your back scratched by others feel good when scratching your own back doesn't?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkp6y5w",
"gkq2lor",
"gkski0c"
],
"text": [
"For the same reason that you can not tickle yourself. I believe it is connected with your mind knowing that the hand you are using is yours, thus translating the whole experience into something you are accustomed to.",
"It makes you want to make friends, so that your friends can scratch your back for you. Scratching each other's backs is an extremely important part of making friends for all other apes and all monkeys. Allowing someone to scratch your back shows that you trust them enough to turn your back to them. Because of this, you will often find young, friendless apes and monkeys begging another to allow them to scratch their back. Back scratching is also more important when you have parasites like fleas or bedbugs, that your friend can pick off of you. Having someone else do it works better than trying to do it yourself. Humans don't have many parasites anymore, and we also have lots of different ways to show friendship and trust (dancing, playing video games, gossiping, etc.), so back scratching has become less important. But because it was very important for our ancestors, it still feels waaaay better to have someone else scratch your back. & #x200B; p.s. scientists call backscratching \"grooming\".",
"Scratching your back against a tree feels even better than having a friend scratch your back."
],
"score": [
5,
5,
3
],
"text_urls": [
[],
[],
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}
|
[
"url"
] |
[
"url"
] |
|
l4lv6p
|
why does drinking water immediately quench the thirst, even though it hasn't reached the necessary body parts yet?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkp3ql2",
"gkq5cxq",
"gkp4ykm"
],
"text": [
"Thirst, just like other sensations like it, are just signals. You are not necessarily dehydrated, or in the case of coffee to pepp you up when tiered, is the body and brain telling your consciousness that you need to refill something - soon. So when the receptors in your month feel H2O, it signals the brain that \"hey, what you ordered is on its way - be kind to the body now please!\" Or drinking coffe/sugary drinks gets you less fatigued even thou sugar and coffee needs to metabolize in your liver which usually takes half to a full hour before real effect.",
"“7 1/2 lessons about the brain” is a short accessible book written by a neuroscientist that answers exactly this question. The gist of it is that the brain 1) relies on predictions to do its job of managing resources more effectively, and 2) produces for you a carefully crafted hallucination (that you call reality) based on inputs and prediction. It takes 20 minutes for the water to have positive effects inside your body, but when your brain realizes (through signals) that water is coming, it predicts upcoming well-being and makes you feel better now. edits: rewrote the whole thing for less sloppiness.",
"Does it? I mean the mouth may feel wet but depending on how much you drank to quench that thirst... may depend on how quickly it’s gone. If you have ever been NPO and could only rinse your mouth but not actually drink... they you will understand that wet mouth doesn’t cure thirst. Thirst is a sensation caused by your brain when your fluid level is down or your chemoreceptors sense increased osmolarity in the blood or gut. When you consume liquids, this adjusts the osmolarity in the gut and triggers the brain to stop the thirst. So, when you drink, it does react the needed body parts in the gut to flip the switch"
],
"score": [
27,
4,
4
],
"text_urls": [
[],
[],
[]
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|
[
"url"
] |
[
"url"
] |
|
l4m3br
|
What actually is an electromagnetic wave?
|
The issue I’m running into is that I understand the concept of waves and the electromagnetic spectrum, but I am struggling to comprehend exactly what a wave is. Like what is a wave MADE of? I get that sounds waves and such are made from a force transferring through a medium, but what about the other waves that travel through the vacuum and near vacuum of space? What are they moving through? What ARE they?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkp60gq"
],
"text": [
"Electromagnetic waves are waves in the electric and magnetic fields. Ok so first you need to know what a field is, which is just a way of assigning some quantity to every bit of space. For example when you look at the weather predictions and they list the temperature in different places, you can see that as a temperature field. Every place on Earth has its own temperature we can assign a number to. Another type of field is that of wind velocity, everywhere on Earth has its own wind velocity, though this is slightly different from the temperature field because it has a direction (which way the wind is blowing) as well as a magnitude (how fast the wind is) while the temperature just has a magnitude (how hot it is). A quantity with both magnitude and direction is a vector, so a field made up of vectors at every point is a vector field. & #x200B; The electric and magnetic fields are vector fields. At every point in space we can look at what would happen if we put a charged particle in that place, if the charged particle would be accelerated then we say that the electric field in that location is the vector along which the particle moves. Basically positive particles will follow the direction the electric field is pointing in, negatively charged particles will go opposite to it. The magnetic field behaves similarly in that its a vector field. We worked out in the 19th century that electric and magnetic fields are actually caused by the same interaction, electromagnetism. If you have a changing electric field you'll induce a magnetic field (like an electromagnet) and if you have a changing magnetic field you'll induce an electric field (like in a generator). If you set up your system in the right way you can have an electric field which changes, this change induces a magnetic field which itself induces an electric field which then induces a magnetic field and so on forever. This oscillation between a strong magnetic field and strong electric field propagates out forever at the speed of light, in fact this is what light is, an oscillation in the electromagnetic fields, an electromagnetic wave. You don't need a medium to have an electric or magnetic field, they exist in a vacuum, this means that waves in the electric and magnetic fields don't need a medium like sound to move through."
],
"score": [
19
],
"text_urls": [
[]
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}
|
[
"url"
] |
[
"url"
] |
l4m8xk
|
Why do we see lights flashing around when eyes closed?
|
When ever I close my eyes at night even though it is pitch black in the room I see flashing lights whizzing past and 'fireworks' types of lights. What causes this?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkplqvp",
"gkq3oji",
"gkq4i16",
"gkpt31m",
"gkpfqhn",
"gkphgkz"
],
"text": [
"My father had that too. His retina was in the process of detaching and he needed surgery. You need to get your eyes checked. If you have that and it doesn't get fixed, you might lose your eyesight.",
"It’s seems to me that you are referring to phosphenes which are the moving visual sensations of stars and patterns when we close our eyes. [huffington post that explains what I think you mean]( URL_0 )",
"I have had this happen for most of my life. Have had many I exams and pictures of my retina and I doctor exams. Everything is fine. It’s kind of like you can see swimming lit up fireworks almost in your eyes. Sometimes I can see this noise so to speak if I’m looking at a plain blue sky .know exactly what you mean",
"What you're describing sounds like [Closed Eye Hallucinations]( URL_0 ). Though I don't doubt there could be a similar experience from detaching retinas, I wouldn't immediately assume that's the case. I've experienced Closed Eye Hallucinations my whole life with no obvious problems (though sometimes distracting when trying to sleep).",
"Could be related to a detachment of the retina. You should get an eye exam to rule that out.",
"[ URL_0 ]( URL_0 ) \\- do you mean hypnagogic hallucinations? The images are quite creepy though but I guess this is what you're experiencing :D."
],
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15,
13,
13,
11,
10,
6
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[],
[
"https://www.huffpost.com/entry/why-do-i-see-patterns-when-i-close-my-eyes_b_7597438"
],
[],
[
"https://www.healthline.com/health/closed-eye-hallucination"
],
[],
[
"https://en.wikipedia.org/wiki/Hypnagogia"
]
]
}
|
[
"url"
] |
[
"url"
] |
l4mjzq
|
Why do we bleed when pricked with a pin but not when we use a medical needle?
|
Biology
|
explainlikeimfive
|
{
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"gkp72q5",
"gkp73gw",
"gkp7tnb"
],
"text": [
"you do bleed when you’re pricked by a medical needle. that’s why they put a cotton ball or a bandaid over it. am I wrong?",
"We do bleed from medical needles, but we bleed less because the hole is smaller. Needles for syringes are very fine because they are designed to be as painless as possible while pins are several times thicker because they are designed to be sturdy. Thicker object = bigger hole in the skin = more blood.",
"These are some images [of a medical needle under a microscope.]( URL_1 ) On this next page [you’ll see a picture of a pin under a microscope.]( URL_0 ) Pushing a relatively blunt object into your skin is going to have a bigger impact than the extremely sharp one from the first picture."
],
"score": [
32,
11,
5
],
"text_urls": [
[],
[],
[
"https://www.evolvingsciences.com/Drag%20Forces%20and%20Friction%20.html",
"https://imgur.com/gallery/Rh7RY"
]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4mmum
|
How does the liquid inside deodorant cans turn into droplets that spray outwards?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkpfo63"
],
"text": [
"There are two effects here. The first is that the propellant evaporates as it passes through the nozzle. This expanding cloud of gas helps to disperse the droplets. The second is the geometry of the nozzle. This has a tiny hole at the front, but behind this there is a tiny chamber with some funky shaped vanes which cause the fluid to swirl. Thus the fluid is spinning as it passes through the hole and is flung outwards. As it spreads out the fluid breaks into droplets. This is the only mechanism available to pump sprays which don't have a propellant. How easy it is to achieve this dispersion of droplets depends on the fluid itself, for example suncream is very hard to spray nicely. If you want to play around with spray geometries then get one of those adjustable hose nozzles where you can go from a single jet, to a cone, to a nice spray pattern. Static electricity is not generally relevant. Source: I design these nozzle inserts for a living."
],
"score": [
9
],
"text_urls": [
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|
[
"url"
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[
"url"
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|
l4mww3
|
What is rent seeking and most specifically defensive rent seeking?
|
Economics
|
explainlikeimfive
|
{
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"gkphtbs"
],
"text": [
"Rent seeking is behavior that increases someone's income without increasing wealth. In economics, most transactions are done because both people are better off, when a baker sells a loaf of bread it's because the baker values the money more than the bread, while the buyer values the bread higher than the money. An economic rent is something that doesn't do that. A simple example is a license to be a baker. If the government only wants 20 bakeries in the town, and makes that many licenses there will be 20 bakers who get the licenses and who make more money than bakers in the next town over, but whose bread doesn't make their buyers any better off.",
"Economic rent is money that you pay someone or something that's more than the cost of bringing it into production. Take Lewis Hamilton the F1 driver -- what it costs to \"bring him into production\" is whatever the minimum sum is he'd be willing to accept to race a car, but he gets paid lots more than that. The difference between what he gets paid and what it would take to get him into a car is rent he receives. It gets called \"rent\" by analogy to land rent -- if you have 10 acres of raw, unimproved nothing, it doesn't cost you anything to let someone else use it for something productive, so (with some assumptions) all the money you get paid is rent. Economists generally don't like rents because it's unproductive spending -- all the money that Hamilton gets above his reservation price doesn't make the car go faster, it just gets sucked up by Lewis (there is a flipside to this though where Lewis should receive his marginal product, which might be much higher than reservation price). It could have gone to materials research or better computing systems that would have helped the car go faster, but now it can't. Rent seeking is doing stuff to try to get rents, usually involving government policy that reduce competition one way or another. bulksalty's example of arguably-unnecessary business licenses is one example. If we have strict licensing for barbers, that makes it expensive to become a barber, which reduces the competition barbers face. This allows them to charge at least some rents over and above what a truly \"free\" market would bear. I've seen a couple of very different uses of \"defensive rent-seeking.\" One is rent-seeking on the taxation side -- looking for loopholes in tax code as opposed to seeking rents by looking for licensing requirements or direct subsidies or something else more \"active.\" The other use I've seen is trying to screw your competitors more than trying to help yourself -- rent-seeking by lobbying for a policy that hurts your competitor. Like lobbying for higher taxes on a factor your competitors use but you don't, so their costs rise but yours don't.",
"Think Deliveroo. They spend millions on advertising. By doing it they capture the attention of delivery meals buyers. All the restaurants now have to sign up for Deliveroo or they lose their customer base. They can't afford so much advertisement because they are much smaller and the scale doesn't allow it. Now a meal buyer buys a meal from potentially the same takeaway restaurant that he would normally buy it from, it is delivered by the same courier guy, but now Deliveroo gets a cut, making it more expensive or reducing the profits of the restaurant. The same meal, the same courier, the same service, Deliveroo gets money for doing literally nothing."
],
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[
"url"
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[
"url"
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|
l4n7qd
|
What happens if new senate cannot agree on a power-sharing agreement?
|
Other
|
explainlikeimfive
|
{
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"gkpbquj"
],
"text": [
"If you have paid some attention to the actions of the Senate in general you have noticed that they have had a very hard time passing any legislation at all. This is per design by the constitution as it means that laws do not change very often which was considered a requirement for a stable democracy. As for the committees they are just administrational functions of the Senate. Instead of having all Senators look in detail at everything they are to pass they have decided to split up into different committees that handles different topics. These committees have no actual power over the rest of the Senate but can come with recomendations. The problem that is mentioned is that even if Democrats have a majority in the Senate with the Vice Presidents split vote Republicans can still delay votes using fillibustering tactics. In general you need 60 Senators to agree to have a vote at all. This means that whenever the Democrats want something to pass in the Senate and fewer then 10 Republicans want it to pass they can delay the Senate preventing anything from being done. This is a tactic which Republicans are known to employ. It is still possible for the Democrats to get things through the Senate by convincing a few Republicans to allow the vote to go through, for example by adding Republican items to the docket that also gets held up by the fillibuster. However low priority items such as committee nominations may be put on hold to get more important things through. This may not have much practical impact. Some of the committees are no more then dog and pony shows for the politicians to publically voice their oppinions and try to humiliate their opponents. However some of the committees do get special and secret information that would be unavailable to the other Senators."
],
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10
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|
[
"url"
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[
"url"
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|
l4o82u
|
Why does water in a kettle go quieter just as it's about to boil?
|
Physics
|
explainlikeimfive
|
{
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"The noise is caused by bubbles of steam forming at the bottom of the water and rising to the surface, but because they're moving through cooler water they condense and pop before they reach it, making noise as the water collapses into the space (this is a process called \"cavitation\"). When the kettle is about to boil properly all of the water in it is at or near boiling point, so a lot more of the bubbles make it through to the surface to get released as steam rather than popping inside the water.",
"This is a pretty tricky one to explain simply, buy I'm going to give it a shot. When you book water in a kettle, there is a temperature gradient across the water - the bottom of the kettle gets very very hot, the bottom of the water is hot, and the top of the water is colder. The noise comes from cavitation, which is what happens when bubbles in water collapse. This creates a very rapid change in pressure, and since sound is a pressure wave cavitation makes sound. When you boil water, everything starts at room temperature. Then you switch on the kettle and the bottom starts to heat up. This heat is slowly transferred to the water, heating it up too. As the water heats up, little bubbles start forming. These bubbles are gas from the air that was dissolved in the water coming out of solution. Since they are lighter than the water around them, they float from the hot water at the bottom to the colder water at the top where they either escape the water or are cooled off first and collapse, making noise. As the kettle continues to heat up, it will eventually get to a surface temperature that's higher than the boiling point of water. When this happens, pockets of steam form at the heating element. Just like the air bubbles, this steam floats up to cooler water where it is cooled, condenses, and experiences a rapid pressure change making sound. The water continues to heat up and mix through convection, until eventually all the water is the same temperature, the boiling point. When all the water is at the boiling point, the bubbles of steam that are forming at the heating element don't lose any heat to the water so they don't condense and don't collapse. This means that instead of making sound, they escape into the air as steam. Hopefully that makes sense! TL;DR; boiling makes bubbles, when the bubbles pop they make sound. When the water is hot enough the bubbles don't pop anymore, so there's no more sound.",
"The noise is caused by vapour bubbles formed near the hot surface at the bottom, but quickly bursting due to colder water above. As bulk of the water reach closer to the boiling temperature, then bubbles near the hot surface start to grow and escape to the top surface instead of bursting at the bottom. So, kettle goes quieter.",
"When hot bubbles hit cold water they pop and make noise. But when hot bubbles hit hot water they keep moving. At the start, the bottom of the water is hot and the top is cold, so the bubbles that rise up from the bottom keep popping. Nearer the end, all the water is hot, so the bubbles don’t pop as they move to the top, so less noise.",
"As an extension of the original question, I'm assuming then that starting off with hot tap water will result in a quieter boiling kettle experience, (and I won't have to turn up the sound on the tv), but I was taught to always start with cold water in the kettle when making tea or coffee, (French press method) due to the level of oxygen in the water (?). Is cold water really necessary and is there a way to make my kettle boiling experience quieter, e.g. is descaling the mineral deposits regularly important?",
"Little bubbles: tiny loud pops at higher sound waves. Then big bubbles breaking on the surface lower sound waves.",
"Heat enters the water at the bottom of the kettle, because that’s where the heating element is. This causes a very thin layer of hot water to form, right up against the heating element, at the bottom of the kettle. The layer of hot water on the bottom and the cold layer of water above it don’t want to mix very much, so fairly quickly, the hot layer stays down there long enough to get hot enough to boil. When water boils, it instantly turns from liquid to gas. This makes tiny bubbles of water vapor that are far less dense than the water that was there a fraction of a second before. This makes the first noise you hear. Those bubbles immediately want rise up like a balloon. But the instant they even begin to expand away from the heating element into the cooler layer of water, they immediately cool and collapse again. The bubbles collapse before they even get big enough for you to see them. Even though the bubble collapses, the heat is still in the water, and the warmer water still wants to rise up like a balloon, which it eventually does. After a period of time, water currents become established, where hotter water constantly moves up, and cooler water constantly moves down to take its place. Once these currents are established, the constant movement of cooler water to the bottom stops any spot up against the heating element from getting hot enough to boil, and the noise goes away for a while. But the overall temperature of the water in the kettle creeps higher and higher, as the water takes turns getting heated at the bottom and going to the top to cool slightly, right before going back down again as hotter water shoots up to take its place. If the lid is on the kettle, this helps the hotter water hang on to more of its heat during its trip to the top of the water and back down. After another period of time, the cooler water coming down to replace the water that just went up is still hot enough that it’s very close to boiling even by the time it gets back to the bottom. Once this happens, when it gets down there, it does boil, shooting back up again, and you can hear the water boiling again. This time, there is a lot more “shooting to the top” movement than when your first heard the initial boiling. The bubbles also last long enough for you to see them, and eventually they last long enough and stay big to reach the top as full bubbles, at which time the state of the water is described as a “steady boil.”"
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[
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[
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|
l4ofhb
|
Why do the walls to a nuclear reactor have to be so thick, if a hazmat suit is fine while you’re inside the chamber itself?
|
Chemistry
|
explainlikeimfive
|
{
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"text": [
"There are a few misconceptions here. First, the walls of a nuclear reactor aren't _that_ thick because they are blocking radiation. The water in the reactor absorbs a lot of the radiation by itself. The \"thick\" part of the reactor building is the containment dome, and it's just meant to keep anything inside if there is a leak or internal explosion. It's deliberately overkill — it's part of a philosophy that says, \"spend a little extra money on concrete and rebar so that if you have a problem it's probably not a HUGE problem.\" When the reactor is running at full power, you don't want to spend too much time in the room with it, as it will have some elevated radioactivity. But once you turn the reactor off, the radioactivity drops a lot pretty immediately. Second, there are basically two types of radioactive threats. The first is the radioactivity itself: the radioactive particles, the alpha, beta, neutrons, and gamma rays. Of these, the gammas are the hardest to shield from, and are why you need lots of mass (of any kind) between you and them to be safe. The other threat is radioactive contamination: bits of matter that are themselves radioactive to some degree that can get inside your body if you are exposed to them. Under normal operation these are always kept inside the reactor. The hazmat suit is mostly protecting you from the latter threat: small, not-that-radioactive particles that, if they get inside your body, can be a real chronic health problem. It is not really protecting you much against the first threat: lots of high-energy gamma rays. So if your reactor has a problem, you turn it off and go inside in the hazmat suit. The fact that you have turned it off turns off most of the acute radiation. But if there is a contamination threat, you're going to want to make sure you don't breath it in, which is why you need the suit.",
"A hazmat suit is not fine. There is no suit in the world that will stop high energy radioactive particles. To adequately shield a reactor you need a lot of something very dense like water, steel, lead, or concrete.",
"The hazmat suit does not block radiation to a significant degree. You use it to avoid getting radioactive material onto your skin or down into your lungs. So it is a way to stop you from getting contaminated not to block radiation. The function is the same as if you use a suit to keep out a chemical that is dangerous to you or to keep pathogens like viruses or bacteria away. If you would go near the used fuel rods from the reactor the direct radiation will be enough to kill you even if you hand a hazmat suit. The radiation from them is less than there was when the reactor was operational but they are still deadly for years. The heat produce will melt them if they are not cooled for weeks and will crack if not cooled for years. An empty reactor where the fuel is removed will be significantly less radioactive because it will only be material in the wall that neutron radiation has transmuted that is radioactive. That is if there has not been an accident with broken fuel rods. The suit will block alpha and beta radiation but so will regular clothes and your own skin. A few feet of air stop them too. Alpha and beta are primary a problem if you get the radioactive material that emits them into your body. The suit will not block gamma radiation or neutron radiation, it is that you need thick walls",
"The Hazmat suit is there for a short exposition to radiation, it will protect you enough to be able to not die in the next months after going near something radioactive for a few minutes/hours. The walls are there to allow people who work nearby to pass relatively close to the nuclear reactor on a regular/daily basis and not developing a cancer after 3 years of exposition.",
"Source: I’m a former Navy nuclear operator/radiation worker. The Hazmat suit is called Anti-Contamination Clothing, or “Anti-Cs”. They consist of a full-body, usually cotton yellow coverall, a hood, rubber gloves, and foot coverings. They do not stop radiation, but rather provide an easy way to later remove and dispose of any potential radioactive contamination that may have landed on you (dust, water droplets, etc). Upon leaving a radiation work area (containment zone), you go through a control point, where you carefully remove the anti-cs and dispose them in a rad waste bag. Then you scan yourself for any remaining contamination using the radiation detector that is set up there. Actually working in a radioactive environment is dangerous, but usually manageable. Forget any movies or stories you’ve heard about running into the reactor compartment to same the crew or something heroic like that. The reactor compartment is locked while the plant is operating- called an Exclusion Zone. Being inside the secondary shield while the reactor is critical (operating normally) will probably outright kill you in a few minutes, or at least give you enough dose to make you wish you were dead later on...acute radiation sickness is not fun. All of the work we do in a reactor room/compartment is done with the reactor shut down. Once the plant is shut down and the door is unlocked and opened, a rad tech will enter with a radiation detector and map out “hot spots”, or areas with higher radiation. This map is posted at the control point, and hotspots are generally marked. Anyone entering the Reactor compartment will study the map first. Once actually inside, limiting your dose is a matter of time, distance, and shielding. Spend as little time as possible near the radiation, maximize your distance to the source (2 feet is better than 1 foot), and try to use shielding where possible. The thick walls of the reactor vessel will provide some shielding, but cannot stop all of it. Typically the reactor vessel will also be directly surrounded by primary shielding, consisting of lead, steel, and water. 2 inches of lead reduces gamma radiation intensity by a factor of 10. Same for 4 inches of steel, and 24 inches of water. Since shielding is very heavy, it is usually optimized to protect personnel in adjacent spaces, meaning some normally unoccupied spaces may have higher rad levels while the plant is operating.",
"The suit is not meant to protect you from an explosion whereas the reactor containment walls are. This could be a steam explosion inside the reactor or an attack from outside."
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|
[
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[
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|
l4ogrd
|
what made Westphalian nation-states different from what came before?
|
I understand in an abstract sense, but I'm looking for hard dilineations between the systems that came before the treaty of Westphalia and how Westphalian sovereignty works. Any explanation would be appreciated.
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkpulwa"
],
"text": [
"Imagine this. I'm a king and I rule over my kingdom. I make the laws and tell people how to live. But the pope in Rome rules over the Catholic religion and by extension, anyone who identifies as catholic. Including some of my citizens. The pope claims sovereignty over my Catholics. And in my kingdom lives a community of druids who have inhabited a grove of trees that have been sacred to them since long before my ancestors conquered many tribes to form this kingdom. They wish to live according to their culture and frankly don't even recognise that their grove is part of my kingdom. The druids claim sovereignty over my trees. And the merchants have formed a guild along with merchants from neighbouring kingdoms that dictate how merchants do business. The merchants claim sovereignty over my trade routes. And my neighbouring king in Russia frequently tells Russian migrants in my kingdom that they should act according to Russian laws. The Russian king claims sovereignty over my Russian subjects. And all of them keep wondering why I keep saying that their trees, souls, trade routes etc. are mine. I'm just some fat jackass in a castle. This makes governing the kingdom a very complex affair. The Catholics complain that their religion comes before the laws of men and as such, they hold the pope's authority above my own. The druids flat out pretend they're not even part of the kingdom and as such won't pay any taxes. The merchants and the Russian migrants frequently act against my interests because it serves their interests that lie across my borders. And all of them feel that I'm being unreasonable for pretending my right to rule supersedes whatever motivates them to differ. I could force them to see things my way, but that will quickly turn violent. Which is exactly what happened in Europe. Lots of warfare because there are many factions with different interests that disagree. The Westphalian nation-state model states that there is a single sovereign government that rules a territory. They, and only they, govern that territory, negotiates on behalf of that territory and essentially represents that territory. More importantly, it dictates that various sovereign entities won't interfere with the governance of another territory. ie. the pope in Italy doesn't get to tell Catholics in my nation that his authority supersedes mine and they should list the pope rather than their king. It's a bit of a simplification but I think it'll help you understand. The whole idea of a sovereign nation seems really simple. There's a territory, a patch of land, and there's someone whose the boss of that patch of land. But for much of history, it was really not that clear who that boss was. Just look at the complicated relationship of the church and the nobility throughout the middle ages."
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3
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|
[
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[
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l4oox4
|
how can expiration dates for milk be so accurate, but for other things be...not ?
|
Is it the actual edibility of something that is being dated? Their freshness? Does marketing play a part in all this. Mom, help?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gkpms5s"
],
"text": [
"Hmm, most things when opened, even milk, will begin to spoil sometime between 5-10 days. Some packages will say something to that effect, like good for 7 days after opening (cheese, some sauces, deli meat, etc). So some expiration dates may be a month and a half away, but they know (and now you/we know) an opened package will not last all the way to that date. Check packages for those ranges, you may find it's more accurate than you think!"
],
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3
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|
[
"url"
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[
"url"
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l4oozb
|
Can you swallow a pill down into your lungs?
|
Biology
|
explainlikeimfive
|
{
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"text": [
"Yes you can. It’s called “aspiration” when something (presumably solid) goes down the wrong pipe and in to your lungs. I’m no doctor, but IMO just an aspirin should be fine, quick googling says it should dissolve on its own within a few hours, you’ll probably have a cough and discomfort until then.",
"Most likely its just stuck in the upper part of your esophagus, pills can be very dry and stick on moist things.. like the esophagus. The wind pipe has a pretty strong coughing reflex for things that aren't supposed to be there and if you can't cough it out, chances are, its not in the wind pipe.",
"Yes, the famous engineer Isambard Kingdom Brunel [inhaled a sovereign]( URL_0 ) doing a dodgy magic trick, and in the end he designed a machine to get it out. And I'll bet I see this on TIL very soon...",
"You would be having a major coughing fit and would be in A & E. Its unlikely in your lungs if you aren't.",
"FYI specifically with liquid gels like aleve if I take them without water it can get a little stuck on the way down and I get a residual feeling like something is stuck there for a while afterwards. Never experienced it with other pills, and it goes away on its own. If you have no trouble breathing I think it’s more likely the pill got stuck in the correct tube and that’s what you are feeling.",
"Also, it often happens that swallowing something can get stuck (even for a brief period of time) and bruise the lining of your esophagus or pharynx. This can make it feel like there is something “stuck” in your throat. Also, if you get something actually into your trachea, you will almost immediately cough it out. It is very rare that an object can get through your trachea without strong attempts to eject it. That being said, I’m not a doctor, and if you feel you may have something stuck in your trachea, you should call a nurse or set up an appointment with your doctor."
],
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|
[
"url"
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[
"url"
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|
l4ox0m
|
What are the differences between Hertz in electricity, in the electromagnetic spectrum, in processors, in displays and in sound?
|
Technology
|
explainlikeimfive
|
{
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"text": [
"Nothing. A hz is a cycle per second. If your screen is 120hz, then it refreshes 120 times per second. If your power is 60hz (A/C) then it cycles 60 times per second Your cpu does ghz or 1billion cycles per second. Each cycle is a chance to do something.",
"Hertz is a unit of frequency: a measure of repetitions per second. Lots of things repeat. In processors, there is a \"clock signal\", a signal that repeatedly turns on and off at a regular interval in order to keep the sub-components of the processor in sync. The frequency being measured is how many times the clock signal switches on and off per second. In a display, the screen displays a still image several times a second to create the appearance of motion. The frequency measured in a monitor's quoted refresh rate is how many times a new still image is displayed a second. Higher refresh rates means more images or \"frames\" per second, which means smoother motion. In alternating current, the live wire's voltage cycles from positive voltage to negative voltage, and the frequency is how many times it cycles per second. In sound, a passing sound wave changes the air pressure changes the air pressure in a spot, cycling it from high pressure to low and back. The frequency being measured is how many times per second the pressure cycles. In electromagnetic waves it is the same as sound waves, except the quantity that is varying isn't pressure, but the energy in the electric and magnetic fields. Hertz are generally only used to measure the frequency of things which periodic (that happen at regular intervals). Other things happen at random intervals, but with a predictable average frequency, like radioactive decay, which has its frequency measured in Becquerels rather than Herts, even though they both mean \"number of times per second\".",
"Hertz is just a measure of inverted seconds. Often times the thing being measured implies some other measurement. If I have a 5 gHz CPU, then what that means is I have 5 billion operations *per second*. If I have 6.5 * 10^14 Hz light, then that light is oscillating 6.5 * 10^14 times *per second*. If I have a sound at 200 Hz, that means the sound waves are oscillating at 200 times *per second*.",
"Hertz is just a measure of frequency, specifically how many times something happens per second. All of the things you list have some property which fluctuates in a measurable way, and the frequency of this happening is shown as hertz, kilohertz (thousands of times per second), megahertz (millions of times per second) or gigahertz (billions of time per second).",
"do you remember when we went to the playground last week? do you remember swinging back and forth on that big swing? we kept counting \"one, banana. two, banana. three, banana....\" and so forth. i was counting how long it took you to go from where you could touch my hands with your toes, swing all the way back away from me, and then swing all the way back to where you could kick my hands again. i was also thinking about how \"often\" or how \"frequently\" you were swinging back and forth. it took you one second to complete one full swing--front to back and front again. in science, we measure how \"often\" or how \"frequently\" it takes for something to repeat itself for lots of stuff--car tires rolling around, waves out on the ocean, a guitar string vibrating, and lots more stuff. we had to pick a unit--kinda like a foot, an inch, or a millimeter, or meter--for this. so, scientists named it for a guy who studied very tiny waves that make x-rays, microwaves, and things like my bluetooth earbuds. his name was heinrich rudolf hertz. he lived a long time ago. yeah, his name does kind of sound like \"hurts\"--just like when you skinned your knee at the playground. yep, i bet it still hurts--or hertz! ha! so these days we can measure all kinds of stuff like electrical current flipping back and forth or tiny waves like gamma rays--y'know like the kind that made dr. bruce banner become the hulk--and sound waves from stuff like a piano string or a speaker using \"hertz.\" do you remember back to your swinging on the swing? it took one second for you to complete one whole back and forth. you're swing was one hertz. if the swing had a shorter chain, you would've swing back and forth more often. you would've had a swing of more than one hertz. if the swing had a longer chain, you would've swing back and forth less often. it would've been less than one hertz. some waves can go very often or frequently. like the note \"c\" on a piano. when you press that key, the string inside the piano wiggles back and forth over 260 times every single second! some stuff like computer parts can wiggle almost two billion times every single second! but when we watch that scary dinosaur movie and the big speaker next to the tv makes a low, rumbly booooom, booooom sound that's a low frequency sound--maybe only 50 or 100 hertz. so, sometimes stuff can move back and forth (or even up and down) very often or frequently. that's a very big hertz number. but, sometimes stuff can wiggle back and forth (or up and down) not very often or not very frequently. that's a small hertz number. we can use hertz to measure all kinds of stuff that repeat their motion. (for older learners: frequency is made up of 1/T. that T stands for period. a period is how long it takes to complete one full back and forth cycle. so mathematically, a big period means a small frequency. think \"less frequently means small frequency.\" for example, a wave that takes 2 seconds to repeat means 1/2s = 0.5 Hz. a small period means a big frequency. think \"more frequently means big frequency.\" a wave that takes 0.2 seconds to repeat means 1/0.2s = 5 Hz.)"
],
"score": [
68,
19,
7,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4pemw
|
How can blowing air into a vagina potentially lead to death? I heard it from somewhere and genuinely don't know.
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkpo1m8"
],
"text": [
"Air embolisms can be fatal. When air can get into the bloodstream it can plug up tiny vessels in the heart of brain and kill you. That said, oral sex isn't usually fatal. You'd need a tear in the internal walls for the pressurized air to get into. Of course, higher pressures are dangerous as they can cause tears. As with all dangerous activities, pregnant women are more vulnerable because the placenta is designed to tear off from the uterine walls, but only after the baby is delivered. Tearing it at the wrong time causes problems."
],
"score": [
11
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4pvcr
|
Why does the time you feel like you were asleep for not match how long you were actually asleep for?
|
There are times I can take a 15min. nap on my break during work and feel like I slept for an hour and be energized for the rest of the day. Yet there are times I can sleep for 8 or 9 hours wake up and feel like I just shut my eyes just couple seconds ago. Why does the mind do this and is there anything we can do to influence or control it?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkqjdeq"
],
"text": [
"Ah, that's called sleep cycling. The body rests in cycles, usually 45 minute intervals (i think), but can also split between 15 minute intervals. That's why \"cat naps\" can be so energizing. If you google a sleep cycle calculator, you can put in the times you need to wake up and it will give you the optimal time to go to bed. I actually have an app I can pair to my fitbit. It can read when I fall asleep, and sets off my alarm at the end of the sleep cycle closest to my actual alarm. I just fall asleep at a better time so it doesn't wake me up too early. Too much of a good thing can be bad, sleep included. Work on perfecting your sleep cycle, it does wonders for me in college. Never feel bad when waking up anymore, and trust me, I am NOT a morning person."
],
"score": [
8
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4pvsn
|
Why is it that when we watch footage from the 70s a lot of times it looks better than footage of the 90s?
|
Technology
|
explainlikeimfive
|
{
"a_id": [
"gkpqexx",
"gkprzct",
"gkpxrp8",
"gkpy9bc",
"gkpt7r9"
],
"text": [
"Older stuff is more likely to be captured on film, while newer stuff is more likely to be captured on videotape. Images on film are captured at a higher resolution and can be restored more easily and to a higher degree.",
"The quality of old film recording was more limited by the technology playing it back than recording it. We can play back old film content with extremely high quality. The quality of digital recording is primarily limited by the technology that recorded it. We cannot add detail that wasn't captured at the time.",
"To add to the \"it's film, not video\" chorus, here's some numbers: 1. The resolution of the NTSC VHS standard (which would have been used to \"videotape\" many things from the 90s) is 333×480 pixels. If you were thinking about this as a digital camera, that would be a total of less than **0**.16 megapixels. Importantly for your question, *that's all that video captures.* There is no \"hidden\" detail we can go extract from an old video tape. 2. The resolution of 35mm film (which would have been used -- at least as a professional level -- to film many things in the 70s) is estimated in the *range* of 100 megapixels. Every film stock is different and it's not possibly to actually measure megapixels on film, so this is just a rough justice estimate, but you can - again, rough justice - calculate that film has somewhere on the order of 500 times more resolution than video. This also makes innate sense -- film was (prior to the last decade-ish) used to shoot movies which we went out and watched on giant movie screens. And it looked great. Video was never intended for anything more than your dinky at-home TV, *before* they got bigger and we switched to HD standards. Video was used when it was available because it was dirt cheap and had instant turnaround -- film was more expensive and required development. What this means now is that the stuff that was captured on video is forever limited to video-grade quality. Stuff that was captured on film (even if it looked shitty when broadcast on TV in the 70's), we can go back and re-scan the film at modern resolutions and it will look great. It's far more likely that stuff from the 70s exists on film than stuff from the 90s, which is the answer to your question.",
"Everybody is explaining it all, so I'm gonna say it in a very basic way. Film is 4k. People just didn't have ways to display 4k quality images in their homes in the 70's",
"If it was filmed in the 70's, it was on film. In the 80's-90's, there were lots of camcorders filming on VHS tape or other tape that got converted to VHS, which wasn't as high quality and degrades over time."
],
"score": [
113,
25,
22,
4,
3
],
"text_urls": [
[],
[],
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4q0ka
|
Can electricty induce cancer like radiation does?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkprkfi",
"gkprmgb",
"gkptn49"
],
"text": [
"In theory yes. (Some) Radiation damages DNA by ionizing the molecule wich can then cause cancer. The issue is that when the voltage is high enough to rip your DNA apart it's also high enough to just pulverize you by ripping your cells apart (and a lot earlier just set you on fire with the generated heat) It's just not possible to direct a voltage precisely enough that it can damage your DNA but nothing around it.",
"If you run enough of it through people, it certainly could. \"Radiation\" is a very broad term, including photons and flying atomic bits, so it's quite general as a \"cause of cancer\". **Certainly** 5G communication does **not** cause cancer, if that's your question.",
"All electric devices create electrical or magnetic fields, often called EMFs. There’s no doubt that our exposure to EMFs has increased dramatically in modern times. Not surprisingly, many people have worried that this is a bad thing. Many false hypotheses, such as the notion that vaccines cause autism, or that acupuncture can reduce pain, show the same pattern: a few small studies produce weak positive evidence, but then larger, better studies fail to back them up. So no, electricity does not cause cancer."
],
"score": [
10,
7,
3
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4q63q
|
What's the process that makes food or any type of consumable spoil, and how does this differ from aging/fermenting stuff like cheese or liquor?
|
Chemistry
|
explainlikeimfive
|
{
"a_id": [
"gkpso4a",
"gkpsqzj"
],
"text": [
"There's two major reasons why food spoils: 1. Biological processes - Bacteria, fungi, mold, insects and other living things find the food, and start eating it and reproducing. Many of these things produce waste that is poisonous to people. 2. Chemical processes - Chemicals within the food react with each other and create reaction products that are harmful or have bad flavors. Aging processes depend on exactly what you're aging but they are generally done under controlled conditions where you can control what organisms have access to the product and limit it to only the ones you want. Fermentation produces alcohol, and alcohol is poisonous to most microbes. Once a liquid has a high enough alcohol content basically nothing can grow in it.",
"Bacteria, mold, or other undesireables colonize the food, consuming it and reproducing and oftentimes creating undesirable and/or harmful compounds in the process. When you age or ferment something, you are colonizing the food with a very specific species/strain that is not toxic and creates a flavor you actively want. Easiest example of this is yeast used in beer - wild yeast was selectively bred for thousands of years to get the highly refined brewing yeast we use today with very consistent flavors and results."
],
"score": [
6,
3
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4qdwd
|
What happens to people psychologically when they have millions of followers on social media?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkpzdjz",
"gkpwaiu"
],
"text": [
"So, humans are a kind of ape. Apes live in packs, and their brains are wired to do a lot of things based on how the pack will react to them. When a lot of apes \"look up\" to one ape, and care more about what that ape does and thinks than they care about the other apes, we say that the ape everyone looks up to is \"dominant\". That's a word with a lot of baggage, so it's hard to say meaningful things with that word anymore. Another word people are using for the thing is \"high-status\", which maybe doesn't have as much baggage yet. But anyways, once an ape realizes that they're \"high-status\", things change in their brains. A chemical called \"seratonin\" which does a lot of different stuff starts being produced more in some areas and less in others, and another chemical called \"dopamine\" starts being produced differently in different places inside the brain too. This is pretty complicated but the most noticeable result is that the \"high status\" monkey starts feeling REALLY GOOD about themselves, stops worrying about things as much, and starts taking more risks and acting more important when they're around other people. There's a word we call \"humility\", which is basically the ability for someone to not act very differently even when their brain notices that people are treating them as high-status. Some people have it, others don't. If Billie Eilish has a lot of \"humility\" then not much is changing. If she doesn't, then all sorts of chemicals are going wild in her brain, making her feel excited and good about herself and less nervous about doing crazy things like making other people mad at her.",
"I don’t have millions of followers nor wish to have in future but some celebrities account are not run by themselves. There are hired people posting behind the scenes so guess whatever is posted is not affecting the said celebrities mentally"
],
"score": [
15,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4qiey
|
If water is added to things like paint, concrete etc is that water lost forever to that product or does it evaporate?
|
Other
|
explainlikeimfive
|
{
"a_id": [
"gkpuvd4",
"gks6j5h",
"gkpuqe0"
],
"text": [
"It depends entirely on the material. For instance, paint. If it's a water-based paint, the water does evaporate eventually. If it's oil-based, it gets separated out first because oil and water don't mix, and then evaporates or gets soaked into the painted material. For concrete, on the other hand, it reacts with the concrete itself during the curing process, becoming part of the concrete itself. Any water that doesn't react gets trapped, like tiny bubbles of water inside stone. If you ground up the concrete into dust and baked it with enough heat, you could get that water back, but for the time, it is trapped.",
"To put what everyone else has said into 1 sentence: water can either be a solvent or a reactant. If the water is used as a solvent (like paint) it will eventually evaporate and join the particles of moisture in the air. If water is used as a reactant (like concrete) it undergoes a chemical reaction and it is no longer water, it is some new molecule.",
"Depends on the product. Concrete permanently absorbs its water (at least until it's recycled or otherwise breaks down within the heat of the Earth in a million years). Paint, when it dries, releases any water mixed in."
],
"score": [
15,
5,
4
],
"text_urls": [
[],
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
|
l4qtv7
|
How do muscles get stronger without growing bigger?
|
How come bodybuilders have more muscle mass than powerlifters but seem to lift less?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkq0l2v",
"gkqfpx5"
],
"text": [
"Once read something along the lines of: \"body building is training the muscle, whereas powerlifting is training the nervous system.\"",
"There’s a couple ways to increase strength, increasing muscle size (mostly bodybuilding) or training your nervous system (powerlifting). When you train your nervous system, your CNS (central nervous system) becomes better at producing more force. This also happens at the individual muscle scale. You have motor units in your muscles that are basically in charge of telling your muscle to contract. Powerlifting increases the amount of these motor units more than it increases muscle size. More motor units = greater total force output."
],
"score": [
11,
7
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4r1n4
|
How are ounces both a unit of weight and of volume?
|
If there are 16 ounces in a pound and eight ounces in a cup, are there two cups in a pound? I'm confused because density varies, so it doesn't make sense for there to be a constant mass:volume ratio? A pound of feathers should take up more volume than a pound of water, right?
|
Physics
|
explainlikeimfive
|
{
"a_id": [
"gkpyxpt",
"gkpzp9w"
],
"text": [
"A (mass) ounce and a fluid ounce (volume) are not actually the same unit. The just happen to use the same word, like pounds (mass) and pounds (force). Just a quirk of old customary unit terminology.",
"If you are working in Imperial then this would be correct assuming the liquid have a density equal to a standard density of water. However if you are working in Standard then it is based on the density of wine. On the other hand the US food regulation requires that neutrition labels require a fluid ounce to be exactly 30ml so as to easily convert to and from metric which is slightly more then Standard."
],
"score": [
11,
8
],
"text_urls": [
[],
[]
]
}
|
[
"url"
] |
[
"url"
] |
l4r6xr
|
Why does our voice sound different when we're tired or we've just woken up?
|
Biology
|
explainlikeimfive
|
{
"a_id": [
"gkq0xsj"
],
"text": [
"When you lay horizontally fluid tends to build up in our upper body. This causes the vocal chords to swell, making the sounds they make to be deeper."
],
"score": [
14
],
"text_urls": [
[]
]
}
|
[
"url"
] |
[
"url"
] |
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