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a6cnxk | Biology | What happens when we get “knots” in our backs? | Best explanation so far was by one of my professors. Imagine if your muscles were plastic wrap. Layer on layer with oil in between in all different directions, everything working smoothly each pulling and expanding you get the idea. Now imaging that oil gets sticky and bunches up no longer can expand and slide. Bam you got a knot. | 1 |
ajpwp0 | Mathematics | If the odds of something is 1/100, and you do it 100 times. What are the odds that you do not get the 1/100 | If the odds are 1 in 100 that it happens, that means the odds are 99/100 that it doesn't happen. So, the probability of not happening is 0.99. If you wanted to know the probability of it not happening twice in a row you would multiply 0.99 x 0.99 which equals 0.9801 or 98.01% To calculate the odds of it not happening 100 times in a row you multiple 0.99 times itself 100 times which is also written as 0.99^100. The answer is 0.366 or 36.6% | 8 |
7620xq | Biology | Why do we try to cure depression instead of prevent it? We tend to try so hard to find out how to "cure" depression instead of focusing on what causes it and how to prevent it. Why? What's with all this chemical imbalance crap? Of course there's going to be something different with the chemicals in your brain. And I know it's not because "We don't know the cause of depression", because that's miles away from the truth. How about try listening to depressed people and why they say they are depressed?? | Because depression is a physical malady, not a purely mental one. You sort of mentioned this, but apparently you are also disagreeing with it for some reason? | 4 |
5w5jhq | Physics | If a bullet fell on my head at maximum velocity, could it penetrate my skull? Because bullets vary, I will take a generic pistol as an example, and with a quick Google search I got Glock G19, which has a 9mm bullet, so we will use this as reference. If this fell from far above at terminal velocity (assuming there is no air resistance and no added external force), could it penetrate my skull? If not, could it do a serious amount of damage? | I don't know if you can penetrate your skull, but it can totally kill you. People die every year for this reason. Try Googling killed by Falling bullet. | 5 |
5sa8ps | Other | whats the difference beween a politician accepting a donation and a politician accepting a bribe? | The only difference is the spelling and pronunciation. If a company gives money to a politician you can bet they are looking for something in return. A politician calls them donations and suddenly they aren't breaking the law. Donations are just bribes that have to be laundered first. | 16 |
lafleu | Biology | Why do some bruises on our body cause swellings, and some don't? | All injuries swell somewhat but how big it looks depends on what's underneath. On your head, the only way the swelling at an injury site can go is outward. In your abdomen it can go in all directions so doesn't look so large. | 1 |
7rmj2s | Repost | How do microwaves not heat up plastic and ceramic dishes? | Microwaves excite water molecules and make them vibrate, there are no water molecules in plastic or ceramic. | 3 |
7r71y7 | Mathematics | Why is sound measured in decibels? Is it logarithmic? If one speaker comes in at 20db, and you add another speaker at 20db, is it twice as loud(40db)? Or are the properties different. | Twice as much sound energy would equal 23 decibels. Doubling the number of speakers or doubling their power would increase the volume by 3 decibels. Quadrupling it increases it by 6 decibels, and having 10x more speakers increases the volume by 10 decibels. | 2 |
7cm02r | Physics | How does supernova have shockwave that can travel through space and trigger star formation? AFAIK, the space is vaccuum, or near-vacuum in some parts, so I'm wondering why can a supernova have shockwave (as stated in a book I read in library, I forgot the book's name) that can also trigger star formation. I know shockwave is a concussion that can only travel through a medium. | That shockwave is radiation and matter(particles) that are accelerated outwards at closed to the speed of light and doesn't require any medium to travel. | 5 |
69o8q1 | Chemistry | What is hot water doing that makes cleaning dishes etc easier that cold water isnt? | I'm not great at Chemistry, but I believe it is to do with the fact that hot water has higher thermal energy than colder water. In the same way that there is thermal energy transfer to melt ice into water, this is causes by transferring thermal energy into kinetic energy (energy of movement) of the particles. Particles in solids have less kinetic energy than particles in liquids. In this case by using hot water, you increase the kinetic energy of the particles of the dirt, or whatever you need to clean, making it more malleable, so it is easier to clean. | 18 |
m5rr4g | Other | Why do cigarette butts smell stronger than actual burning cigarettes? | It's the chemical build up being drawn through the filter with each drag. It was a pain for me to hide them as a teenager just because it was exponentially stronger than the cigarette itself. | 5 |
69fr9a | Culture | Why does the USA celebrate Cinco De Mayo? | A few reasons 1. We have a large population of Mexicans and people of Mexican ancestry 2. We love tacos and cinco is a great excuse to eat tacos 3. We love beer and cinco is a great excuse to drink beer For additional context we also celebrate Oktoberfest, st paddys day, Bastille day, and loads of other days though celebrations might be more or less extensive depending on the population who identify with that particular nationality | 3 |
5vwlqm | Culture | How did the whole world agree on the duration of a second? | The first clocks were sun dials, and originally the duration of a day was divided into 12 equal segments by the Egyptians. These became hours, and obviously over time we discovered ways of counting the hours during night time as well. The Babylonians divided the hour in 60 minutes, but it took a long time before minutes could be accurately measured. In Medieval times in Europe a wide variety of mechanical devices were created that mimicked the sun dial (which is what decided which direction clockwise was). The mechanical clocks started to measure out minutes, although they were frequently inaccurate especially at this level of precision. In the 1600s Christiaan Huygens invented the pendulum clock, and this was the first device that could accurately and reliably measure minutes. Over time the pendulum clocks were improved and made more accurate, **it was only at this point that we were able to measure seconds**. Around this time we began to redefine time. Previously time was based on the Earth rotation, the passage of the sun across the sky, as reflected by the sun dials of old. With these new mechanical devices we were able to have a more accurate way of measuring time. For a while a second was defined as a fraction of a year, 1/31,556,925.9747 It wasnt until the invention of atomic clocks that we settled upon the now standard length of time elapsed by a second. Technically a second is defined as: > the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium-133 atom We chose the caesium-133 atom because it has an extremely regular periods. And we chose that 9.1 billion number because it was extremely close to the accepted length of a second at the time. | 6 |
ghzbyb | Mathematics | What does "x as a function of y" really mean? | If x is a function of y, it means that the value of x is controlled by the value of y and only one (or no) value of x is possible for any given value of y. | 2 |
gghcza | Physics | This is an infrared image of Jupiter. Why does Jupiter have alternating belts of hot and cold? [Image]( URL_0 ) | Everyone seems to be missing the most simple answer: convection. When gas gets hotter, it expands, becomes less dense, and rises. When it cools, it contracts and sinks. If any of the heating, be it from internal sources or the sun, are uneven, you'll get bands and sections of rising and falling gasses, separated by their temperature. It's weather! Check out [infrared images from the GOES satellite]( URL_0 ), It shows similar heat distribution. The puffy clouds here are earth are also made through convective action from uneven heating. | 5 |
i2qxnq | Biology | Why are people so much stronger when they are on drugs or experiencing a psychotic episode? | [ URL_0 ]( URL_0 )I read this article about it like a year ago. It explains it pretty easily, while blowing your mind EDIT: It does not speak about drugs, but it explains why we can't always access our "super strength", even though we have it | 5 |
8039s9 | Biology | Why does it hurt to read green text on red background and vice versa? What happens to our eyes/brain? [Example]( URL_0 ) | I don't know that it "hurts", but I'm getting a strange 3D effect on the text. Closing one eye at a time, I notice that the text looks very different to each eye. Darker and with more of an outline to my left eye, versus a solid clear red to my right eye. And now that I'm not looking at it anymore, I did get a quick eye strain sort of mini headache. Maybe it *does* hurt a little. So maybe the hurting is simple eye strain due to the extremely high contrast causing the differences in your eyes to become much more prominent and obvious. | 4 |
ielnj5 | Biology | Why is physically exerting yourself to the point of exhaustion at the gym good for you but various jobs involving manual labor seem to cause permanent damage in the long term? | 1-3 hrs/week with the option to stop if you get injured (and people still manage to get bad injuries) vs 40-80 hrs/week | 15 |
kkuul9 | Chemistry | How does just water clean cast iron? I was recently gifted a piece of cast iron, and I've never owned one before. A lot of people say to not use soap on it. Just rinse it with really hot water, dry it off, throw some oil on it, and store. I'm going crazy here, scratching my brain over how just water can clean something (especially when you've cooked a meat) when dishsoap has been stressed my entire life. EDIT: Thank-you everyone for all your comments! | It doesn't, fully, but that's part of why cast iron works. "Seasoning" cast iron is just burning layer after layer of oil onto it, which forms a nonstick layer of complicated chemicals. New oils from cooking then fuse onto this layer each time the pan is used, carrying some of the subtleties of the foods cooked in it. You avoid soap because it will wash off this layer, leaving the iron exposed (and removing both its nonstick properties and its resistance to rust). Fortunately, very little is going to grow on mostly-clean metal, and whatever does grow gets quickly cooked off the next time you heat the pan. Plus, you're usually using cast iron at high temperatures, which leaves little opportunity for viable foodborne illness to be present after cooking anyway. | 3 |
5vwd9w | Repost | What is autism? And what is the difference between mild autism and high-functioning autism? | Autism is a pervasive developmental disorder, giving rise to a range of symptoms concerning perception, behaviour and intellectual capacity. People with autism range from severely handicapped to almost normally functioning. The severity of autism is a continuum, referred to as the autism spectrum. In the most recent diagnostic manuals, the several subtypes of autism have been removed, and the diagnose is now Autism Spectrum Disorder, which includes such diverse previous diagnoses as Asperger syndrome (normal to high intelligence) to seriously disabled patients in need of constant care. In reference to another answer here which defines "high functioning" autists as "being able to function, on some level, without constant supervision", I find this to be seriously under-representing the capacity of these people, as many high-functioning autists are able to live perfectly normal and independent lives. Source: Am parent of "high-functioning" autist (Asperger). | 3 |
jtck9y | Economics | What’s so difficult about banning cruise ships forever. Less than 100 cruise ships pollute more than 10 times all the European cars combined. We didn’t have them for past few months and world was doing fine. What’s the incentive to keep them going forward? | Cruise ships are a big money industry. Shipyards makes tonnes of money building them, cities get tonnes of money when they come into port, and the companies make tonnes of money operating them. This industry also provides regular people with jobs. You say that world was doing fine without them, but you have to keep in mind that many places are facing an economic recession. When our Covid issues are resolved, and we need to get the economy back on track, Cruise ships will be too good to turn down. | 25 |
hzdalc | Biology | What's that somewhat painful "fizz" in your nose experienced after drinking carbonated drinks and then burping? | It's particulates, carried by the escaping gasses, irritating your sinus cavity. Tiny droplets of soda and stomach acid rise when the air escapes and your nose isn't as separate from your throat as you might like it to be. | 2 |
ek7dwk | Chemistry | I bought a wooden Valentine’s Day box from target. The back says “EPA TSCA Title VI compliant for formaldehyde”. Can someone explain this in a simpler way than google? | It basically means that your product meets the EPA's ( URL_0 ) requirements for the levels of formaldehyde that outgas/release from the manufactured wood product. Too much and it is bad for people to be around as formaldehyde (CH2O) is a known carcinogen. | 2 |
i1t2ao | Technology | Why can't game servers differentiate between people who get disconnected and those who choose to leave a match? | You can definitely tell if someone used the game menus to leave, since that will send a signal to the system. If someones internet legitimately cuts out or they've sabotaged it you can't really tell. However, you still kind of want to punish people similarly, but compound the punishment for repeat offenders. If someone keeps disconnecting, they either are sabotaging their connection, or they have such a bad connection that is is unreliable. In either case, it is unfair for the other people on their team. They either get paired with someone who is leaving the game intentionally, or they get paired with someone who has an unreliable connection and may not stay with the game. | 3 |
8rzx78 | Biology | The difference between a 500 calorie breakfast and a 500 calorie lunch vs. no breakfast and a 1000 calorie lunch | Sadly enough, you're not going to find a scientific answer on your dietary/biochemical question. Not even on r/nutrition or reddit as a whole. Part of the reason being that everyone has an opinion about food related questions even more so then in other fields (history, anthropology, etc...). Another part of the reason is that yours is a biochemical question and not something for a dietician. And lastly, your question is suprisingly difficult to answer because our knowledge about this part of human biology is limited. I would recommend a researcher called Satchin Panda, he is currently writing a book about how the time of day influences our hormones and our metabolism. You can expect different calorie uptake in the morning, noon and in the evening, even for the exact same meal. Something called chrononutrition. Good luck. | 9 |
jk3lft | Other | What a Meme is in really simple words | A picture or drawing that expresses emotion or a somewhat complex idea. It's meant to convey the emotion or thought quickly, as a picture or drawing is absorbed faster than reading multiple lines of words. | 3 |
6fgoyb | Culture | Why do so many Asian nationality adjectives end in "ese" (i.e. Chinese, Japanese, Vietnamese, etc.) where so many other nationality adjectives end in "ish" or "an" (i.e. Scottish, American, German, Egyptian, Italian, etc.)? I know there are exceptions, but in general, this seems to be a thing. Edit: I mean nationality adjectives in English, not their native languages. edit edit: For instance, Portuguese and Korean are exceptions, and then you have nationalities like "Czech" and "Filipino" which don't end in "ese," "an," or "ish." | We get our language/nationality names from European explorers who first made contact and had to call them something pronounceable. Those ending in "ese" were countries first visited by explorers speaking Italian, Portuguese, or a similar language -- this ending is normal in those languages. Those ending in something else were first visited by explorers speaking other languages. | 29 |
j3pfio | Engineering | Why all racquet sports have oval racquets? Why not any other shape? | Modern tennis rackets have been quite a few different shapes over the years. And some of them have been quite close to round. But current tennis rackets have the more elongated shapes they do for a few reasons: Most rackets are made by just a few companies, and the brands tend to copy each other. Changing the most common shapes now would take a very clear indication that the new shape was way better and would provide more sales. Generally speaking, the longer the strings, the more responsive they will be. So racket designs try to put the longest strings where the player will want to hit the ball. Rackets designed to shift the sweet spot closer to the handle will be more egg shaped than oval, with the wide part near the throat. Those made to place the sweet spot closer to the tip will be more like an upside down egg shape. Since the main strings have more of an effect on power and performance than the cross strings, those are lengthened more, causing the racket to be elongated rather than round. This shape also allows more margin for error in terms of how close to the body the ball is hit, making the racket easier to use. And distance from the body is a bit harder to judge than height. Making a racket wider also makes it a bit less streamlined and aerodynamic. So oval rackets are larger than the equivalently wide round racket while compromising aerodynamics a little less. Psychologically, they also look and feel more streamlined. When a racket is swung, it actually isn’t just level, it rotates around a central point (the hand). When you diagram the swing path, you can see that the oval racket actually covers more area more efficiently than the round frame. The rules of tennis state that a racket’s “hitting surface cannot exceed 15 1/2 inches (39.37 cm) in length and 11 1/2 inches (29.21 cm) in width”. This means that the width is the limiting factor in terms of head size, and racquets can be longer than they are wide without breaking the rules. All that said, as rackets evolve, we may see that we find new reasons to change the shape of the head further, based on new learning and technology. | 2 |
hf0hk5 | Chemistry | What are the reasons that make a flame go blue or yellow? What happens to it's light exactly to shift perceptible colour? | It depends on the degree of chemical combustion. Complete combustion (lots of oxygen) makes a near transparent/blue flame from production of nearly exclusively CO2. Incomplete combustion (not enough oxygen) makes carbon, CO and some CO2. The imperfections cause the flame to be yellow and give off smoke | 1 |
733fok | Technology | what is the difference between a dependency and a prerequisite? | A pre requisite is a sort of dependency but in a particular order. It must be done before the next task/thing. A dependency can be anything that relies on something else but not necessarily in a specific order. | 2 |
5rpl20 | Culture | Why do some bands release more songs on Japanese editions of their albums? | TIL 85% of Music sold in Japan is made up of CD sales : [source]( URL_0 ) | 3 |
7ixfsb | Engineering | How Do jet engines work and what’s the benefits of using them over a standard internal combustion or Wankel engine? Is it possible to use a jet engine in a car? | Jet engines are faster, they output more thrust. Both operate by reacting gases to make an explosion. the jet engine uses that explosion itself to push forward, while a standard engine/wankel engine uses the explosion to spin a wheel. propeller planes and almost all cars just spin wheels because the materials are easier to get (cheaper), the control is better, and they don't use as much fuel. Jet engines are faster. you can put a jet engine in a car (thats how the land speed record was set). Its just hard to control and unsafe to drive on normal roads. | 2 |
fng7bg | Economics | How does bailing out massive industries with millions or even trillions of dollars compared to the general population help improve the economy? | First, most bailouts come in the form of loans which must be paid back. Second, although it might not seem apparent, goods don't appear on shelves by magic. Products and services we rely on have to be provided by some organization. There is no point giving citizens money if there is nothing to spend the money on. That being said, it isn't a case of either or. The situation is such that demand stimulus (cash to people) and supply stimulus (keeping companies running) are both going to be needed to avoid a long depression. The government needs to provide cash to people because some job loss and disruption is already happening and will likely worsen in the short run. But doing so is a stopgap - people consume goods and services not money. And goods and services are mostly made by people through companies. | 2 |
71mg6t | Other | If a dentist makes money off people with bad teeth, why would I use toothpaste that 4 out of 5 dentists recommend? | Dentists earn salaries, they aren't paid commissions. Every advanced tooth operation is a chance for something to go wrong and for their reputation to be tarnished. They just want everyone to have nice, clean teeth so they can breeze them through the office. Why would dentists want to make their jobs harder? I never deliberately make my job harder. | 2 |
n2cio4 | Mathematics | How does a folded sheet of paper 42X be the distance to the moon? | Because each fold doubles the thickness, not just adding one paper. So the first fold is 2 papers thick, the second 4, third 8, and so on. You'd reach about 500 pages thick about 9 folds in. (512 to be precise) So to reach the folds to the moon you'd just have to take the distance to the Moon, divide it by the thickness of paper, then find the first power of 2 that's greater. | 7 |
abrvl4 | Chemistry | Why is deep deep water cold, even if technically it's closer to the inber center of Earth? Hi! I hope my question doesn't sound stupid. Yesterday I was thinking about this and even if for some lengths I can think of an explanation, I'd love to hear a more technical answer to this. Why is deep water super cold (to the extent that only certain animals can survive in it) and not hotter as it's technically closer to the centre of the Earth? (I know the inner core is super far still, don't worry). Thank you for your time! | The core of the Earth does not really contribute much to the heating of the surface. It only plays a factor in certain places and even then the energy from the sun have much more to say on the temperature then the volcano or hot spring nearby. But for water the convection have a much bigger role in the temperature then anything else. The difference in water density that just a few degrees of temperature makes will cause the water to circulate. Water is also a bit special as it gets less dense both at higher and lower temperatures. So the temperature at the bottom of the ocean or lake is at a constant 4C. | 5 |
5vqm8a | Other | How do they synchronize the sound so perfectly with images in complex musical movie scenes such as the last 11 minutes of whiplash ? I mean, they must've shot so many takes of that scene, probably on several days, but after the final montage, the sound, the music, the images, all fit together near perfection. | I don't know the movie you're talking about, and so I don't know how old or new it might be. But I am a musician who plays on the soundtracks for many video games and movie scores and can speak about the way it's done now. In scenes where the music is just "background" and doesn't have to match up with specific events you can be a bit more lax about the process, but if you need the music to match up exactly here's how they do it: Composer gets a final copy of the video. It's all timed and cut the exact way it'll appear in the film. The composer will make a note of important actions in the film and exactly how far apart they are (e.g.: the two swords hit each other at 1:42.556 and 1:45.637). Then they will come up with a musical idea or melody that would fit the action and they'll do some math to find out exactly how fast the music needs to be so that the two big orchestra hits happen exactly at those times. A lot of times this means that the music will be at an oddly specific tempo, like MM 135.8. Then they write the music at that tempo so the two big chords happen exactly in line with the film. Next they go into recording with the orchestra. The orchestra all have headsets on with a "click track" going. The click track is programmed to click at exactly 135.8 beats per minute so it will be the exact tempo needed to fit the action on screen. Then they record the piece and it's perfectly synced with the action due to the musicians all hearing the click in their ears and playing at the right tempo to match what's happening on screen. | 3 |
5vp3v6 | Other | Are 2 in 1 shampoo and conditioner just shampoo and conditioner mixed together or is it a different chemical? | Found this really good article from the huff post. As it shows, shampoo and conditioner chemically are incompatible. So 2 in 1 try to get around that by taking some elements of conditioner (eg softening), but you can't get the full effect, as in consecutive usage of shampoo, then conditioner. URL_0 | 18 |
9ted2k | Engineering | How does a massive site like flickr transfer everything to new owners? | Usually you'd expect the infrastructure to be part of the buyout, i.e. flickr servers become smugmug servers. Its quite possible that the servers (and storage) are rented, rather than owned, in which case the new company takes over the bills and the access to the servers. | 1 |
gqo5rb | Biology | Why is it that unhealthy foods taste so good(chocolate, soda, candy, fried foods etc.) despite it being bad for us while healthier foods (veggies, whole grain etc.) taste much worse in comparison? Wouldn’t our bodies recognize which foods that are most beneficial and demand to have more of that? | Our bodies evolved for about 2 million years to crave the most energy efficient food - because when you run into something energy dense like sugar, it can mean a difference between life and death for a hunter/gatherer who hasn’t eaten in 3 days while stalking a herd of prey animals. So sugar cravings are hardwired in our physiology. Because sugar was rare, and hard to obtain. Same story with fat - when most of things you eat are nutrient poor, like grass, berries, roots, random meat you had to run down on the savannah, an occasional bite of fat could power you for days. But again, finding that fat was rare and hard work. Now, fat is easily available.... | 4 |
bv13zi | Other | Why don’t more countries use nuclear power? | It depends on what time period you are talking about because in Europe it cause a mass protest movement in the 80's (especially in Germany and Austria) in which they held a public referendum where the people voted to end all nuclear power. They were worried about the effects waste would have considering the power plants that were being protested were close to the Danube river. While others simply can't afford or get access to the materials needed for nuclear power. Others are worried about the effects it would have on their economies due to international intervention. The US is still sanctioning Iran for following all the INF regulations agreed to in the Iran nuclear deal and what other country would want those sanctions that cripple the economy. Other countries have not used it as much because of accidents like what happened in Japan when a nuclear power plant was hit by a tsunami causing even more damage to the surrounding area than if it weren't there. When it comes to international politics there usually isnt one broad answer to cover all countries because each country is different and will have different opinions on different subjects, just as different people have different reasons for not liking a certain food or drink. | 1 |
66atno | Biology | why we can't immunize against the bacteria that causes tooth cavities TIL that tooth cavities are caused by bacteria that we are not born with, but we aquire from others just like a communicable disease. So why can't we immunize for it or treat it with medication in the same way we treat other bacterial infections? | First of all, I read that same post on Reddit and it's BS. Yes, you aren't *born* covered in bacteria but it's very true that you depend on bacteria to live. Bacteria are on your skin. They are in your intestines. If you're a girl, they are all up in your vagina as well. And while they can sometimes make you sick, some of them are quite helpful to you. Bacteria are ubiquitous in the environment and they will colonize you no matter what you do. Yes, you might get your mother's when she kisses you the first time but you also get covered in bacteria climbing through the birth canal. They are on practically everything you touch to the food you eat to the air you breathe. No, you do not get cavities like communicable diseases. While they can cause some diseases (endocarditis, abscess, certain types of pneumonia under the right conditions, infections from being bitten by other humans) brushing your teeth works pretty well just as bathing does. Developing vaccines against them would not only be a waste of resources it would do very little to prevent cavities since your immune system isn't protecting your teeth. When you brush/floss and you bleed, your immune system handles them just fine on its own unless you have certain risk factors--and those *do* get antibiotics before dental procedures. And if you do get sick, endocarditis or pneumonia or otherwise? We give you medicine. You also have to keep in mind, what would the medicine do? Antibiotics are in you blood and the bacteria on your teeth are not. If you want to kill the bacteria, you brush your teeth, but they are just going to come right back. Also keep in mind that antibiotics don't just kill the bacterium you want--they kill lots of other bacteria, too. And when you kill off the good bacteria, really bad bacteria can take up residence in their place and make you sicker. Additionally, frivolous use of antibiotics also selects for drug resistant bacteria so not a good idea. TLDR: Cavities are not communicable diseases. The bacteria that cause cavities are generally handled by your immune system just fine, but your immune system is not protecting your teeth. Brushing your teeth periodically to get rid of them is a better solution than medication in a similar fashion to bathing regularly. | 2 |
d7u57s | Biology | How do painkillers know which pain to kill? | For things like tylenol, aspirin, ibuprofen etc. those molecules block the production of signals that are related to inflammatory pain...kinda like a sore knee. Whenever we have trauma in our body, we get inflammation, and actors in our immune system come in and try to fix things. Those actors barge in the door and cause some discomfort and pain. Those drugs tell those actors to not invite themselves as often or disconnects the phone line that calls the actors in the first place (called eicasonoids). & #x200B; Drugs like gabapentin play with neurotransmitter (the equivalent of a signal for a nerve) levels that are involved in tickling pain related to nerves or what we call neuropathic pain. & #x200B; Medication like opioids (hydrocodone, morphine, etc.) fit into a receptor...and when that receptor is occupied, a signal turns on to create substances that cause overall warmth and euphoria that mask general pain we feel..like a distraction. These don't necessarily address the underlying condition that is causing pain...like having your tissues ripped out after a surgery, but the distraction is good enough to feel the pain and give your body time to hopefully heal. & #x200B; Tl;dr meds are designed to target different types of pain by playing with how the pain pathway (of which there are multiple) gets relayed in the body. Different meds work on different types of pathways, and there are sometimes but not commonly, overlap. That's why the meds know which pain to kill and that's why we don't have a one size fits all painkiller. | 4 |
7qg2p2 | Culture | Why do TV networks advertise new episodes in EST/CST but not in other US based time zones? | In the West they advertise in Pacific/Mountain time. Depends on where you're watching the show. | 3 |
ct8w38 | Engineering | Why does engine power peak in the middle of an engine’s RPM range? Why wouldn’t a higher RPM lead to more power? Why does a torque / horsepower curve peak below redline? | Engines are more efficient at lower rpm's (to a point). That's cuz the expansion of the hot air in the cylinder isn't perfectly efficient. The slower you go, the more efficient it is. But on the other hand, the higher your rpm's the more power-strokes of the cylinder you get per minute. The optimum balance between the two is at peak torque, usually mid-to-high-range of the engine. Where that peak is, whether its 4k rpm or 8k rpm, depends largely on the design of the engine. | 3 |
6xd9i4 | Biology | Why do some people always feel tired after waking up (no matter how many hours they have slept), and others always wake up with a burst of energy? | Do you wake up in the morning, or are you woken up? This makes a big difference. If you rouse, you are awake when you get out of bed. If you are heavily asleep when someone or something wakes you up, you take a fair while to wake up. In addition, different people will need different amounts of sleep. | 22 |
c572n0 | Economics | Why do car dealerships do "cashback" instead of just reducing the price? | Cash back comes from manufacturer, not dealer. It may be dependent on other offers, such as cash back instead if taking low interest financing, or only on a purchase but not a lease or vice-versa. And it’s a short term incentive to boost sales when needed, where lowering the price sets a new lower benchmark price for all future sales. | 2 |
98iedm | Technology | Sometimes in video games and in video game glitches the characters will all of a sudden fling up into the sky at a thousand miles per hour. If games attempt to stimulate mass and physics, what are they getting so wrong that causes this to happen so regularly in video games? | There's a variety of causes but sometimes the physics computation gets bad data as input. Under the hood physics engines are basically just math formulas. Games are dynamic and it's impossible to account for every single combination of things the player does or anything else that might happen. So sometimes the game will give the physics engine numbers that are too big or too small, etc and weird stuff happens as a result. | 3 |
9tfr74 | Biology | How does Type 1 diabetes develop later in life? I have a friend (19/yo F) who recently found out she has Type 1 diabetes after going into shock and being hospitalized. She told me the doctors said she had probably had it for a least a year, and that it was "dormant". I always thought that Type 1 was something you were born with and Type 2 was something thst develops in adults. A Google search could really only tell me that Type 1 can sometimes develop in people over 30. How? Is this normal for a 19 year old? What is it that can cause the body to just stop producing insulin? | Type 1 is an autoimmune condition. Essentially your body's own immune system destroys the cells that create insulin (pancreatic beta islet cells). There can be a genetic link and this typically develops early in life, although theoretically could occur at any time as it can be just a random chance that the cells that attack the pancreatic cells are produced by the immune system. It typically presents in childhood or adolescence, and as the cells are broken down over time it can be several years before symptoms become noticeable. In worst case scenarios, and not uncommonly, you don't realise what is happening until you go into a state known as diabetic ketoacidosis (DKA), a life threatening but very treatable state. This happens when your body can't use glucose for energy any more, as it needs insulin for this, so it breaks down fat into ketones instead, which have the side effect of making your blood too acidic. If your friend was hospitalised, this is likely what happened to them. Type 1 diabetes is managed by insulin injections, to replace the insulin that is no longer produced. Type 2 diabetes usually occurs later in life. It is insulin insensitivity rather than insufficiency. More common in older, overweight people, your body just becomes desensitised to the effects of insulin so it has a lower effect. DKA is less likely, as there is usually some insulin there which does enough to help you use some of the glucose, but not enough to deal with all of it. Type 2 is managed with diet and medications to lower blood sugar and increase the effects of insulin. In more severe cases insulin can be used as well. These are the classic diabetes categories. They are also known as insulin dependent and insulin independent. In reality, there can be some overlap between the two Edit: added section on type 2 diabetes | 1 |
84q361 | Chemistry | How does toothpaste do all the things it claims to do on the tube in the 2 minutes it takes to brush my teeth? | At its base, toothpaste is liquid sandpaper that tastes minty. The fact that it's an abrasive is what separates it from just using your toothbrush without toothpaste. As far as other additives like flouride, flouride starts working immediately to remineralize your enamel, though longer is better. Ultimately, you need to remove all of the bacteria from your teeth, tongue, and cheeks, and you can do most of that in a short amount of time. Again, longer is better, but you face a diminishing return the longer you go. | 1 |
nmjv75 | Biology | Why do human voices become more “gravely” with age? | Vocal cords are muscles and muscles get weak with age. Or they get stiff depending on the person. | 1 |
bmqu8y | Biology | Is there any truth behind the popular belief that if a wound is itchy, it means its healing? If so, why? It's just something my mother always used to say and I never wondered about it until now. | This article explains it really well. Here's an excerpt: "The cells unite at the center, attach together and contract to pull the wound shut. This process creates a mechanical stress that activates the itch nerves and tells the spinal cord to scratch. These nerve fibers can also be activated by chemicals secreted by the body, which is how wound healing causes itching. As the University of Cambridgeexplains, the body releases histamine in response to the wound and its sudden exposure to outside elements as a protective function." Source: URL_0 | 1 |
60s6ct | Other | Why do you need a Master's Degree to become a librarian, especially when the median salary is barely above $50,000? On Jeopardy tonight, one of the contestants stated that he obtained a Masters Degree online just to become a librarian. | Because it makes you a smarter librarian, I am very grateful to all the librarians that have helped me along the way. They are the unsung heroes to how we have advanced as far as we have in many fields. I thank you all so much! | 95 |
in1j24 | Technology | why is it not allowed to use special characters in a filename? Back in the day I guess those characters served a different purpose as well but shouldn't that have been fixed by now? | Many of those characters still serve the purpose they did 40 years ago. While it may not look like it modern operating systems are based on and have inherited many characteristics of their predecessors. Today everything you do is done with a GUI, but deep down your computer acts with the same logic as its ancestors which had nothing but the command line. In those days you worked with programs and files by simply typing the name of the program followed by the name of the file it was supposed to work on. For example: edit mytext.txt Would open the file name mytext.txt in a texteditor. If you wanted to open a file in a specific directory you would need to type something like: program /folder/folder2/file.ext This would open the file name file.ext in the folder named folder2 inside the folder name folder. The character "/" was used to tell the computer when the name of a folder ended. If you allowed the character inside of the names of folders and files it would get confusing very fast and you would have no good way to tell apart a file name "fi/le.ext" from a file name "le.ext" inside a folder name "fi". Other forbidden characters served and still serve similar functions. characters like $ and * originally worked as placeholders is DOS, while characters like > and | were used to tell DOS what to do with the result of the program they just executed. The same logic that applied decades ago still does. While it might be possible to create a new OS that would not have such a legacy this would mean that all the program written in the past decades would no longer work on it. Microsoft is and has always been very much in favor of erring on the side of caution with these things. They would prefer not to let users shoot themselves in their own foot and to keep things consistent because developers are users too. Linux for example has similar issues but they do allow users to actually use a number of characters in file and folder names that will break many command line scripts and programs. Linux will happily load your gun for you if you want to shoot yourself in your own foot. It is a different design philosophy. MS are very much in favor of playing it safe. For a good example of this try to create a file simply named "con" or "nul" or "PRT" in a modern windows. It doesn't matter if you capitalize any of those letters. It also doesn't matter if you give it an extension like ""Nul.txt" or where you create those files. This all doesn't matter because the version of the OS from which those restrictions are inherited didn't support things like folders or extension yet and didn't support making a difference between a file name "a" and one named "A". Engineers could have at any point in the last few decades said that only the NUL in a specific directory would work as a NULL device and everywhere else the name was okay to use f something else, but they didn't because they thought that there were programs that might rely on things working the way they were, so even in the newest version of Windows things are kept the way they were in the early 80s for compatibility reasons. | 4 |
gtdh1b | Technology | How is it possible that we can't explore the remaining 97 percent of the ocean when NASA takes pictures of galaxies million light years away. | We can examine any point of the sea's floor that we want. Send out a sonar ship, send down a submersible. Spend a week there and you get really good pictures of that spot. It is similar to the sky. We can closely examine any point we want. We spent 10 days of hubble's time to take a deep picture of a tiny, tiny bit of the sky, a part of the sky that looked boring, and found it crowded with galaxies. Since then we have let hubble look a patch of the sky over months, and seen even more. But we haven't done that to all of the night sky. So it is a bit similar. We have examined small parts of both the sky and the ocean floor very carefully and learned a lot. But we don't really know a whole lot about either of them. | 11 |
6dj4vk | Physics | Why hasn't anyone else been to the moon? It seems like something that super rich people would do for fun, like James Cameron going to the Mariana Trench. [title] edit: I appreciate all the responses, and while you all explained like I'm five, you weren't rude and that's appreciated The general consensus is that it would be a stellar (lol) waste of time and money, only to do something we've done before. | To even the most dollared rich folk, heading to the moon would be a huge proportion of their wealth. Rich folk don't get rich by being the kind of person to blow all their dollars on a single trip. Plus, risk of fiery death. Typo fix. Ed. | 7 |
gsg0q8 | Engineering | In a normal piston-cylinder combustion engine is it more beneficial to have a larger bore and fewer cylinders or smaller bore with more cylinders? or does it cancel out? | It really depends on the application. Surprisingly there is no overall optimal engine design. Every engine makes tradeoffs. This one might be small, light and powerful - but it's expensive and doesn't last long. This one might be super efficient, but isn't very responsive. This one might be amazing in all aspects, except its really polluting so needs an expensive aftertreatment solution. Generally: A long stroked engine with fewer big cylinders can be more efficient and produce a decent amount of torque at low speeds for a given displacement (Big truck diesel - lots of torque and good efficiency) A short stroke engine with more little cylinders can rev fast and be power dense, but sacrifices low speed torque and often doesn't last as long. (motorbike - lots of power from a tiny engine). A short-stroke big cylinder engine is unusual. The reciprocating mass is too high to rev it fast, and you don't gain the efficiency benefit of the long stroke. A long stroke small bore is difficult/impossible to make because the conrod hits the cylinder wall. Then there are considerations like low cylinder counts are quite unbalanced and don't sound great. This is why car engines are generally 3 or more cylinder. | 1 |
65gsk6 | Other | why if someone is being bullied on school property or if it's between students why is the school's responsibility [other] | The school takes the place of the parent while the child is there and everyone who works there from principal to janitor is a part of that process. | 4 |
lg2my2 | Technology | Car thermometers, how do the get the correct temperature without interference from engine heat/wind drag etc? | The wind is your friend if you like to measure temperature. So you put the sensor where air from the surrounding will blow over it before the car can heat it up, the simplest way would be in front of the engine. The wind chill is relevant you try to keep something warmer or colder than the air like a human but for a sensor that should be at the same temperature as the air wind simply make it faster to respond to a change in air temperature. You as a human-like to stay at a constant temperature. So you put on clothes to reduce the rate heat can leave your body. If the rate is the same as you can produce heat you will keep a constant temperature. If you replace air around you and from your clothes that you have heated up with new cold air you will cool down faster. The feal like temperature is help for you so you can determine the number of clothes you need. The value is calculated from a model of a human in a specific set of clothes and a bare face walking into the wind, it is not a general value for how the extra cooling effect of wind. That is why wind chill is important for you. The air is not cooler because of the wind it can just cool you down to its temperature faster. If the goal is to cool down an object to the same temperature as the air the wind will cool down faster. The wind will increase the speed at the temperature drop but not what temperature the object will be finally reached. The air can only cool down an object to its own temperature. The win will result in faster cooling but the final temperature is the same. & #x200B; The result is a temperature sensor it an object you like to have at the same temperature as what you measure. So the wind from the car moving will result in a quicker change in temperature. What you like to keep the sensor away from is direct sunlight because it can heat it up. | 2 |
5q9kp9 | Biology | Why do we suddendly lose motivation when close to finishing a task? The last 20% is always the hardest to me. | Starting a task is harder for me, then there's the overcoming unforeseen obstacles part way through that is difficult too. | 8 |
lhc7h5 | Technology | Why is it so difficult to make synthesized instruments sound like their real-world counterparts? | First, I want to suggest that your experience might be coloured by 'availability bias'. If you ever hear a synthesized instrument good enough to fool you, then, more or less by definition, you won't know you've heard one. One pretty popular brand of synthesized and sampled acoustic instruments, is the Native Instruments Kontakt line, and you can listen to previews of many of their soundpacks here: [ URL_1 ]( URL_1 ) Instruments like these are used extensively in movie soundtracks as well as other music. I bet that lots of them will sound pretty real to you. & #x200B; But why is it hard to do this in general? The answer is a bit different for each instrument. Fake pianos started to sound a lot more convincing a lot earlier than fake guitars, for instance, because there isn't all that much playing nuance to capture in a piano note. The note can be struck hard or soft, and it can be held long or short, and that's just about it. Two parameters, velocity and duration. In piano playing, all the expression and nuance doesn't come from fine details about the note itself, but from how they're put together. A single note on the guitar, though, can have all kinds of inflection on it - picking technique, fretting/voicing, bends, tremolo, all that stuff. It's a lot more work to come up with a simulated model of a guitar which captures all those things about someone's playing style. And even if you \*have\* come up with a convincing virtual instrument model, that doesn't necessarily mean composers and players will know how to use it effectively. Most music composition and production software has a quite generic, non-instrument-specific approach to writing out melodies and chords. There's no standard way, for instance, for a composer to tell a virtual guitar instrument, which chords should be strummed upwards and which should be strummed downward. People using these instruments might have to manually edit their compositions note-by-note to add tiny minuscule timing offsets to simulate strumming, since if all 6 notes in a guitar chord are struck at exactly the same time, it will sound unnatural. It's the same for many other instruments, like saxophone or violin, which allow for a huge number of different ways to play a single note. Most computer and keyboard-based composition workflows do not have good ways to expressively simulate those technique nuances. Edit: Here are some examples of [wind controllers]( URL_0 ). If you wanted to get a convincing synthesized saxophone sound, controlling it with one of these would be a must. Playing the sax line on a piano keyboard or drawing it out on a sequencer grid just wouldn't cut it. | 2 |
ced4tc | Biology | why do mammograms require the breasts to be squished flat when we are able to take X-rays and ultrasounds through fat and muscle masses? I’ve never had a mammogram so I actually don’t know how it works. Only heard the jokes about how they squish your breasts and that it hurts. We were talking about how men can have breast cancer so why don’t they get mammograms? (Maybe they do). Then we laughed as we pretended to slip a tiny man boob into an imaginary mammogram machine (that I’ve never seen). So I thought they can do X-rays and stuff. Why do they *have* to torture you to get the results. Did some sick doctor invent the machine, laughing the whole time about how evil and unnecessary it is? /s Biology tag? Idk. | After my first mammogram I was called back for a second. Then an ultrasound. I am still asking the same question: if mammograms are superior why was I sent for an ultrasound when a lump was found? Why aren’t we just ultrasounding the boobs from the get-go, like we do the ovaries and pregnant bellies? It’s obviously an inexpensive technology now... (I was okay, it was ultimately ruled “probably not cancerous” per the little card I got in the mail) Anyway, back to searching these comments for the answer to OP’s question! | 18 |
cgf8po | Biology | What is that electric shock that you get when you hit your elbow on a specific spot ? | You have nerves running down your arm. When you hit your elbow just right, that force presses on the nerve causing it to send a bunch of signals to the brain. Normally, the nerve carries sensory information from your arm, so the burst of signals are interpreted in your brain as a wide variety of intense senses, causing the distinctly weird feeling as a result. | 1 |
hap4o8 | Biology | Why is it that some have very visible veins on the hands and some not? What does it mean? | Just depends on how much subcutaneous fat you got and how plump your veins are. Thinner skin and lower body fat % means more visible veins. | 2 |
5xjsjf | Other | Why does going the speed limit save gas? | Once a car's in its highest gear, going faster takes more fuel. That means there is usually an optimal speed that's lower than the speed limit, but since the alternative is usually speeding, going the speed limit is better than going as fast as the car can go. | 4 |
koenam | Biology | how seedless fruits keep being grown? Like if you have a seedless clementine, or grape, what is used to plant the next generation of that fruit? | Grape vines can be propagated by cuttings - cut a bit of the vine, plant it and roots will emerge. I'm curious about seedless watermelons | 4 |
l18lnd | Other | Why is it that people are sentenced to death, but stay on death row for decades? | The appeals process can take quite a long time. Even though the deadline for appealing a trial on its own is quite short there are other deadlines such as appealing a trial due to significant new evidence or applications to the Office of the Pardon Attorney for recomendation of a presidential pardon. A lot of people on death row will get their convictions overturned one way or another. Innocent people are being put on death row all the time and they need a chance to clear their name like everyone else. Back when Great Britain had capitol punishment they did in fact require that the sentence were carried out as soon as possible. However there were several cases of innocent people who got hung before we knew all the evidence. Among other one high profile murder case lead to the conviction and execution of the suspected murderer but then the real murderer was caught at another murder scene and confessed to both murders before getting hung himself. So the wrongfull conviction not only let a murderer go free to kill again but also caused an innocent man to get executed. This is the sort of events we hope to avoid by keeping convicted men on death row for decades before their execution. | 5 |
az6uwj | Biology | Why is it that our senses of sight and hearing seem to be much more prone to being defective at birth than our other major senses? ex: I have never heard of someone being born without taste. Or is it just as common, but less noticible in that in doesn't interfere as much with every day life? | Sight and hearing are used as our main social communication. Defects in taste and smell are less noticeable and have limited impact on life. Touch defects are rare as its generally difficult to not die before reproductive age without it. | 3 |
gti2gd | Technology | Why do old recordings (tv / audio) sound so nasally? Watching old movies or broadcasts always sound the same. Everyone has a very muffled and nasal sound to them. What caused microphones to produce such a uniformly weird sound? | One factor is the recording media, which in combination with microphones can dramatically roll off frequencies at the top or bottom. Older recordings were on film, tape, or vinyl, which introduced their own artifacts like compression and graininess. You end up with a reproduction that is missing much of the nuance in human speech, like chest resonance and sibilance, so you get that nasally quality. It was also a factor in how broadcasters spoke, as someone speaking normally would not be as well understood. | 6 |
ltpwv3 | Physics | Color vs fluorescence Hi, & #x200B; I got some fundamental questions which I could not find the answer to on the internet: & #x200B; 1. Objects have color because they reflect certain wavelengths. So, that must mean that the rest is absorbed? How is it possible that an object can only reflect 1 color? 2. What is the relation between color and fluorescence? How is this illustrated in a energy diagram? If all objects absorbs light, does that not mean that all objects are intrinsically fluorescent? | 1. Yes, the rest is absorbed and becomes heat. You must consider that the spectrum of light is pretty much continuous, especially for macroscopic objects the definition of "one color" in the sense of a single wavelength doesn't exist; usually it is a whole band more or less wide of wavelengths that gets reflected. Furthermore consider that the human eye can only recognize three colors, every wavelength in between 700 nm and 635 nm for us is *just red.* 2. Color, as you said, comes from the wavelengths that are reflected. Fluorescence involves a few more steps: light first gets absorbed, loses some energy, and then is re-emitted with a longer wavelength (lower energy). | 1 |
7447h6 | Other | How is it possible to cook while camping without being attacked by animals? | > Wouldn't the smell attract every nearby animal that eats meat to your campsite? Wouldn't you be surrounded by hungry bears or mountain lions by the time your food is ready?? Smelling meat is something which may attract predators, that is true. But smelling *cooking* meat can only mean one thing: Humans. Traditionally speaking humans have been by far the most terrifyingly lethal predator in any environment and most animals will respect this fact. While these days they might come across some helpless city slicker who couldn't fight their way out of a wet paper bag, the instinct to avoid humans have been bred into wild animals from a hundred thousand years of primitive humans who ruthlessly slaughtered any animal foolish enough to stumble into a human camp looking for food around the campfire. | 2 |
lb4ffr | Earth Science | What makes PNW forests very un-walkable and Northern European forests very walkable? There's an obvious answer: PNW forests have huge thick bushes that you can't walk through, while the ground of the forests in, say, Sweden or Finland, is all moss and smaller plants. Of course I am curious to know how and why this came about. I did see a similar thread from 5 months ago called "Why do some forests have undergrowth so thick you can't get through it, and others are just tree trunk after tree trunk with no undergrowth at all?", but I want to understand this specific comparison more. Both have been logged, but I know the logging and replanting practices are different. Also the weather and climate are different. So, I want to understand what role each of those plays. | Quite a lot of European forests have been managed for thousands of years. They've been cut down, burned, replanted, encouraged to grow in specific ways because that was how you got a lot of timber in the shapes you wanted it, and farmed for plants that grew well in wooded areas. Underbrush has been cut back to let humans move around easier in the forest, to encourage new growth to attract game which was then easier to see and shoot, and so on. That hasn't happened in the Americas to anywhere near the same degree because the population was much sparser. | 2 |
aesbpn | Biology | What are the factors that make a wound leave or not leave a scar? Is there a way to know for certain if it will leave a scar or not? | When the wound isnt to deepthe skin around is still have its "data" when the wound is deeper or wider the data is gone. And will have new skin which is smoother, leaving a scar. | 2 |
hk1cwx | Biology | why does scar tissue form instead of new skin? | New skin cells don't really have an arrangement to them, imagine taking a bag of dominoes and scattering them all over the floor, they're pointing every which way. When skin heals and forms a scar all the cells are arranged in straight lines, like dominoes joined together edge to edge. | 8 |
ihi76m | Other | What are subjective morality and objective morality? What's the difference? | Objective morality is the idea that there is a correct answer and response to every moral issue. Subjective morality is the idea that different people can have different answers to the same moral issue and it is possible for them all to be right, or at least not wrong. | 3 |
gix4kg | Economics | why do companies have a limited time on branded door items e.g:McDonald's double quarter pounder with cheese | There is no non-marketing reason to limit the availability for the double quarter pounder as it is made from stuff they always have on hand (at least in the US) For stuff like the Shamrock shakes - they are stealing appliance capacity from other permanent products and it is not popular enough to surpass those sales year round For stuff like the McRib it was originally seasonal because they only buy the pork when the market price on hogs was at the seasonal minimum and they wanted to keep the unit price in-line with the other products. | 5 |
jhcg99 | Physics | why does this type of geiger counter work? So im in 8th grade and my project is radiation. Im planning on making this geiger counter and dont really get how it strips off the electrons with just wire. Here is the link [ URL_0 ]( URL_0 ) | The wrapped wire type works primarily with the alpha and beta particles and less with the x-ray/gamma. This has to deal with the penetrating distances of types of radiation. Since alpha and beta are charged particles they have shallow penetrating distances making them interact close to the tube wrapped wire. This particle charge creates a change in the voltage potential as it interacts with the electrons which is then measured by the counter. | 1 |
l7ckr5 | Economics | Stock Market Megathread There's a lot going on in the stock market this week and both ELI5 and Reddit in general are inundated with questions about it. This is an opportunity to ask for explanations for concepts related to the stock market. All other questions related to the stock market will be removed and users directed here. How does buying and selling stocks work? What is short selling? What is a short squeeze? What is stock manipulation? [What is a hedge fund?]( URL_0 ) What other questions about the stock market do you have? In this thread, top-level comments (direct replies to this topic) are allowed to be questions related to these topics as well as explanations. Remember to follow all other rules, and discussions unrelated to these topics will be removed. **Please refrain as much as possible from speculating on recent and current events.** By all means, talk about what has happened, but this is not the place to talk about what will happen next, speculate about whether stocks will rise or fall, whether someone broke any particular law, and what the legal ramifications will be. Explanations should be restricted to an objective look at the mechanics behind the stock market. EDIT: It should go without saying (but we'll say it anyway) that any trading you do in stocks is at your own risk. **ELI5 is not the appropriate place to ask for or provide advice on stock buy, selling, or trading.** | Watching the big short starring brad pit, Ryan gosling, Christian bale on Netflix after learning about the stock market and shorts was like a completely different movie. Absolutey amazing movie | 489 |
5qij5w | Physics | What would happen if we detonated an atomic bomb in the eye of a hurricane? I was wondering what would happen if an atomic bomb was detonated either directly above or right in the center of the eye or a really powerful hurricane. Could it possibly destroy the storm? | A hurricane gets its energy from warm ocean water, and in the process of water vapor condensing into rain droplets. The heat released during condensation serves to continue to warm the surrounding air, which causes more seawater to evaporate, condense, and continue the cycle. A fully developed hurricane releases 50 or more terawatts of heat energy at any given moment, only about 1 percent of which is converted into wind. The heat release is equivalent to a 10-megaton nuclear bomb exploding every 20 minutes. The entire human race in 2011 used about a third of the energy present in an average hurricane. So bombing a hurricane might be about as effective as trying to stop a speeding Buick with a feather. It will make the hurricane worse because: 1. There's the possibility that bombing the hurricane, if it had any effect at all, would just add to the storm's heat supply, making it even stronger. 2. You're creating a radioactive hurricane. | 4 |
l00sb4 | Physics | What’s the difference between an explosion and an implosion? | An explosion is an increase in pressure that expands outward. An implosion is a decrease in pressure that sucks inward. Also describes something falling into itself. For instance, demolishing a building with explosives designed to weaken the structure so that it implodes into itself. Another example would be breaking a light bulb. It's a vacuum inside, so when it breaks, the glass imploded instead of explodes. | 3 |
98nf27 | Biology | female voices are higher pitch than male voices, so why can you still hear the difference between a male and female voice when they sing the exact same note for example? | Listen to BeachHouse and circa survive. You may be surprised about the genders of the singers | 17 |
78pnzo | Chemistry | Why do they say that the kitchen sink has more bacteria than your toilet? | Like I said, at first I only linked to the nutrition facts video that, had you watched it or looked at the transcript, you'd see specifically cites bathroom vs kitchen bacterial comparison study. The rest is background I gave after being downvoted. Look at the title of study 2. It's talking about fecal. I even linked the full text. It's the original source of the statistic about toilets versus sinks, and it's focused on bacteria in meat. No, 2/3 are not addressing the specific question, but I doubt most people realize how much fecal bacteria is on their meat, and it certainly supports why kitchen sinks are more contaminated than toilets. The sources link under the nutritional facts video has several studies about how problematic this bacteria is and why "just cook it well and clean up afterwards" is not working well. | 3 |
6grykr | Culture | As a German with not much knowledge about the US, please explain why Florida is so often made fun of/spoken badly about | Along with what others have said about the legislature for open records, Florida also has one of the worst school systems in the USA and is a big contributor to the "dumb American" stereotype | 8 |
hrrd3l | Engineering | How do we communicate using electromagnetic radiation? So I understand that, with radio for example, there’s a transmitter that takes information and sends it out, and a receiver that takes in the information and does stuff with it, but how does that work exactly? How do the electrical signals get converted into, essentially, the same thing as light? How does electromagnetic radiation even carry information? Why do we only use certain bands of the electromagnetic spectrum for communication? TIA | without getting too much into the weeds, electromagnetic waves propagate through what we call the electromagnetic field in a very similar way to how ripples propagate through water. The electromagnetic field exists everywhere in spacetime, much like water exists everywhere in the ocean. Imagine dipping your finger into a pond. There will be some gentle ripples. Now, if you thrust your finger into and out of the water, you will create more ripples which follow the pattern of your finger movement. In this analogy your finger is an antenna, because if someone (receiver) were able to analyze those ripples, they would be able to tell exactly how you (transmitter) moved your finger in the water. The pressure your finger puts on the water is analogous to voltage. Applying a difference in voltage to an antenna will cause the electrons within it to move, which is what causes the ripples in the electromagnetic field. The peaks and valleys of these ripples are then interpreted as information. This is the fundamental idea behind transferring information through waves. | 3 |
a6ev62 | Economics | Why do multi billion dollar companies like Amazon need subsidies like tax benefits to open branches/offices in new places? | Cities want tax revenue, and they want jobs. If a big company is looking to open a big office in a new town, the city has an incentive to try to lure them there, because the office will theoretically provide a lot of tax money and new jobs. If other cities are doing the same thing, they'll get in a bit of a bidding war to try to give the company the best deal. & #x200B; They don't *need* those tax breaks at all. Amazon is worth a trillion dollars, they don't need NYC to give them $5 billion for an office building. If anything, there's a real debate at the moment whether those incentives have gone too far. They're expensive for the city and offset a lot of the new tax revenue, and in many cases the jobs go to people the company brought with them rather than to locals in the city. So all the locals get is increased prices for housing and such as the new employees come in and gentrify their area. | 2 |
mxf5lv | Physics | Why is foam white no matter the color of the soap? | Light bounces off of objects until one colour sticks. Foam is made out of lots and lots of little objects, so the light bounces in all sorts of different directions. A colour cannot stick, and so it looks white. | 5 |
k8nuyk | Biology | would someone born in a hot climate feel more cold if they moved to a cold place like Canada and vice versa compared to someone already living in a cold climate? | They will definitely 'feel' cold. My family is from the Caribbean but I was born and raised in Canada. When they come visit, they are cold, wearing jackets when I think it's summer. When I visit, I find it too hot too function and just lay under the A/C while they are wearing full clothes and working outside. I can't say how much of that is just what we are used too vs actual physical differences. Maybe I just need to suck it up and learn to like the heat? | 2 |
bh1jvq | Physics | why would a ball stop bouncing on the ground If you drop a ping pong ball on the floor, it will bounce smaller and smaller but eventually stop. Why doesn’t continue to bounce but just at a continuously smaller height. | Lots of reasons. For one, there’s friction introduced from the air that is an additional force slowing it down. Another is that whatever ball you use will deform slightly every time it’s dropped, absorbing some of the energy. I’m sure there’s more reasons that I’m missing but that’s just what I thought of off the top of my head | 2 |
5twllf | Technology | why do vocoders require that weird tube in the person's mouth, and not a microphone? | Ah, perhaps you are conflating the all electronic vocoder (no tube) with the Heil Talk Box, made famous by Peter Frampton in 'Do you feel like we do'. The vocoder takes a microphone input and a synthesizer input, and mixes the two so the voice modulates the synth sound. It works electrically. Example: Kraftwerk's 'It's more fun to compute'. The Heil Talk Box has a speaker inside, and a tiny amp circuit. The guitar is connected to this, and the box sits at the guitarist's feet. The tube goes up the mic stand, carrying the speakers sound into the players mouth. Now the player can modulate the guitar tone by moving their mouth- an acoustic process. The microphone picks this up, and the usual big guitar amps are muted while the talk box is on. These two gadgets both make a hybrid voice and instrument tone in completely different ways. | 3 |
dc8sgl | Economics | If the top 1% of the population has more than 50% of the worlds wealth, why can't the other 99% just take it from them? Edit: I did not literally mean going to rich people's houses and rob the money. But to just pass a law that takes most of their money and redistributes it. | > But to just pass a law that takes most of their money and redistributes it. Because a) that would solve nothing and b) the situation would return to the initial 1%/50% in two generations. | 7 |
lq654f | Mathematics | The Monty Hall math problem I was watching Brooklyn 99 Season 4 Episode 8 around the 5 minute mark The problem goes "There are 3 doors behind one of which is a car. You pick a door and the host, who knows where the car is, opens a different door showing nothing behind it. He asks if you want to change your answer. Apparently the math dictates that you have better chances if you change your decision. Why? 2 doors 50/50 chance, no? One character (Kevin) says it's 2/3 if you switch 1/3 if you don't. What? How? Please help. | The key detail: the host can't reveal the prize door, and the outcomes of the choices don't ever change. By being forced to only reveal a non-prize door, the host is disclosing information about the other choices. | 8 |
5yfrpa | Biology | Is there a reason that you perceive time to move slower on some days and faster on others? | One reason that days get faster as you age is pretty interesting. the first day of your life was 100% of your life at the time. The second was half. The third was a third, and so on. Each day is a smaller fraction of your life than the one before. The same goes for weeks, months and years. This is why life goes by faster as you age. | 6 |
maviao | Economics | How does kidnapping insurance work exactly? | Same way as medical insurance but with kidnappings. Medical emergency happens, you get a bill for 500,000 dollars, but yay! You have insurance that you pay for and the insurance covers it! Kidnapping (or other crises, sometimes including other violent crimes, depending on the plan) emergency happens, you get a ransom note, “pay us 500,000 dollars”. But you don’t have 500,000 dollars on hand, but yay! You have kidnapping/extortion insurance, and they step in to help. Same premise, just for a different kind of emergency. | 1 |
mm2bbr | Technology | (HACKING) How are bruteforce, dictionnary and hybrid attack still a thing when a server can just limit the number of attempt per seconds ? | Just because something can be done, doesn't mean it *is* done. Some people write bad websites that don't have this kind of limitation. | 3 |
lxq9la | Physics | Why does the rotation of a wheel on a car force the car to move? I was told it was due to the wheel 'pushing the ground and propelling the car,' but this seems a little basic. I know it seems stupid but I can't grasp the Physics behind it. Thanks. | Because of friction mostly. Not sure where you're confusion is but you might just be over thinking it. | 4 |
oa342z | Other | What is the difference between a power chord and a regular chord in guitars? I am trying to differentiate the two but do not understand the music theory jargon explaining the two. | Whole lot of explainations, not a lot of "like I'm five." A typical chord is three notes. One of these notes will make the chord sound either happy or sad. If you take that note out, the chord sounds more neutral. In a rock song, neutral can sound pretty heavy and powerful, thus "power chord." | 4 |
6slrrs | Biology | Why does the human body like vibrations so much? I have noticed that the human body really likes vibrations a lot. Like massage machines, when somebody roughens up our hair, etc. I was wondering what could be the reason for it. | Can I add a question? It seems related that we like swinging - why is swinging in a hammock more relaxing than lying still? | 4 |
nfo9e6 | Other | How did ancient Polynesians first find all the remote Pacific islands? Did they just sail in random directions hoping to find land? EDIT: Please stop giving this post awards. There's no reason to give money to reddit because you like my post. If you really feel compelled to spend money, donate the price of the award to charity or something. | what I was told on Tonga, was that in addition to things mentioned already like birds and waves bouncing off land. Such as, feeling turbulence, or a "wake" thrown off by islands as the ocean currents cut around them. you sail into that, feel it, and follow it to land. Then another thing was, apparently, there are relatively consistent swells that come from the same direction, we don't notice them because of all the surface waves, but the skilled navigators could pick them up and use them as a reference, I think also they might get disturbed or blocked by a land mass, not so sure about that last bit, or any of it, I went to Tonga once and it was badass | 15 |
hbi45r | Biology | How can hospitals put us in medically induced comas and remove us at any time, but can't remove people from a coma that isn't medically induced? | I think it's like choking someone you can stop choking them but you can't unchoke in the same way. When it's medically induced you are doing something to keep them in that state. | 3 |
ijwnz0 | Biology | Why most birds are fine with you being near until you make eye contact with them and they fly away? Why are they afraid of eye contact? | Eye contact for a bird is very, very different than for a human. Birds do not have binocular vision. When you think you are making eye contact with a Bird, from the Birds point of view, you are staring at it like a weirdo | 3 |