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6wszd6 | Engineering | Why do power lines emit a loud buzzing/static sound when it rains? [video for clarification]( URL_0 ) | It depends on the power line, there are a couple high voltage (220Kv I believe) above my house, and they buzz all the time | 2 |
md6a4h | Biology | If radiation causes Cancer, How does radiation(Chemo) kill cancer? | Well Billy I'm glad you asked. We first have to get rid of the concept that Radiation directly causes Cancer. What actually happens is that intense radiation can damage the DNA in cells which can lead to serious issues down the line, cancer included. Chemo as you called it doesn't use radiation. Radiation therapy however, uses the same principle of radiation leading to damage causing cancer but on a focused "beam" to try and spare as many healthy cells as possible and damage the cancerous cells instead. Edit: as u/Eona_Targaryen has said, what OP is referring to as Chemo is actually Radiation Therapy. | 4 |
701yhe | Chemistry | Why are we able to "painlessly" put down our pets with drugs, but often botch lethal injections? Why does this happen? Couldn't we just do some math and give the human a higher dose based on BMI and height? What's the difference between the drugs; do we even use different drugs for dogs and humans? | Also, a simple and effective means is available: Nitrogen. It makes up 70% of the atmosphere, and breathing in pure nitrogen feels no different than air. The lack of oxygen would make you pass out, but without any of the buildup of CO2 that is associated with suffocation (burning lung sensation). It is dangerous in industrial settings where a few breaths can render someone unconscious without realizing that they aren't getting oxygen. For this reason, you have to have an oxygen monitor in areas where nitrogen is present in the workplace. There were 80 deaths in US workplaces from 1992 to 2002 due to nitrogen asphyxiation. In fact, wikipedia tells me that Oklahoma signed a bill authorizing nitrogen asphyxiation when lethal injection chemicals are not available. I believe that historically, the method was seen as "too humane", which is interesting since lethal injection is also supposed to be humane. | 24 |
lztbm4 | Other | How does a cavalary charge work? I don't understand why Horses wouldn't be afraid to charge into a wall of humans with weapons. And if they would do it, wouldn't the first row tumble and all the other incoming horses would trip over them resulting in a domino effect? | [This post from a military historian]( URL_0 ) should be helpful, especially if you've seen *A Game of Thrones*. | 8 |
6h1w48 | Economics | What was the original motivation behind the F-35 program that would have justified how much it's been funded? Setting aside the infamously ridiculous amount of delays, ballooning costs and hardware problems the program has had, I've been wondering: what possible motivation could the Pentagon have had for sponsoring a program designed to spend tens—if not hundreds of billions—of dollars even by its original estimate? What was wrong with the current fighter jets like the F-22 and USAF fleet that they needed to be replaced with hundreds of these new fighters? Why was this necessary when most of the conflicts the US finds itself in now don't seem to rely much on fighter superiority? Not being partisan and not looking for partisan answers about government bureaucracy or whatever: I'm just trying to understand the Pentagon, Lockheed and Congress's motivations in commissioning this thing in the first place—and why they thought it was worth sticking with. | Jets have a limited lifespan; as they fly and pull Gs, heat up and cool down, their materials eventually fatigue, crack and break. The F-16, Harrier, A-10 and F/A-18C/D are all approaching their use-by dates. The F-16 in particular is the main jet of the USAF, the F/A-18C/D makes up half the Navy / Marine air combat fleet and the Harrier is the only jet that can operate off Marine Corps LHDs / LHAs. In addition, Russia, China, Iran, North Korea, etc have continued to develop new weaponry (tanks, jets, air defences, etc). Sure, the US is not at war with either, but militaries are designed to fight the wars you can't afford to lose. That means you're just wasting money if you intend to buy more of the same old aircraft. A big factor in all of this is that it takes a long time to develop a modern fighter - the first US jet fighter took < 18 months to go from concept to flying. A modern fighter (F-22, F-35, Typhoon, Rafale, PAK-FA, J-20, etc) takes about 20 years to go from concept to in service. To just manufacture an already-designed fighter takes about 2 or 3 years. Combine that with the expectations that a near-pear war (eg NATO vs Russia or China) would be a lot quicker than WW2, and also the fact that the supply chains of these jets reach around the world, and you end up with a situation where if you're going to fight a war, you're only going to be able to fight it with what you already have. In the case of the Joint Strike Fighter (F-35), the US is building a "5th generation" (same as the F-22) strike fighter that provides qualitative (it's been getting > 20:1 kill ratios against F-15s and F-16s) and quantitative (the US + allies are buying > 3000 F-35s; that's more than Russia and China's fighters combined) advantage to ensure that the US / NATO can control the skies and win any conventional war. If you're thinking about nukes at this point, you have to understand that the understanding of the global and military effects of nuclear weapons today is much different to what it was 30 years ago / during the Cold War. The Soviet Union believed that after they and the United States exchanged nuclear missiles and bombs, that they'd be able to have a considerable number of forces survive, with those forces then being sent out across Europe to try and conquer as much as possible. Today we're aware how unrealistic that scenario is and so even if WW3 broke out, there's a decent chance that nuclear weapons would be used in a more sparing fashion, if at all (look up NUTS - Nuclear Utilisation Target Selection). If you're Vladimir Putin, etc, you'd probably like to retain the option of having you and your family escape to some secluded island or 3rd world country without worrying about radiation and dramatic climate change destroying your hope of survival. | 7 |
ar90d1 | Culture | Why do people with Downs Syndrome seem to be far more functional in society than they were a few decades ago? | All of the long detailed replies here are great, but it can be tl;dr in two basic bullet points: * Better education tailored for their disability * They're given a chance and treated as human beings | 35 |
kyr3ah | Other | Why are UFC and boxing matches the only mainstream sporting events where fans need to purchase PPV to watch it live? | PPVs are such a weird thing. I think that never existed in Germany, but we don't even really use PayTV. Who would pay fucking 30€ for a 3hr Event? I have no clue how that works, who pays that? Not to mention you can probably easily watch it for free Online. | 3 |
9576rd | Other | Why does California burst into flames every summer? | Humans also planted a lot of Eucalyptus trees in California - they deal well with heat and drought, but they also burn like fuck, which perhaps they didn't think about... | 26 |
k6rhgr | Chemistry | Why does spring water taste sweeter than mineral water? | There are two parts to this: 1. The mineral make-up of the water influences its flavour. A water from any given spring will taste slightly different to the water from another given spring. The same is true for mineral water - depending on the makeup of minerals in that water, it may well be sweeter than water from another spring. 2. The psychological effect. People generally can't tell the difference between tap water and bottled water if they aren't told which is which: URL_0 > hese results indicated that the participants could not distinguish between the two water varieties and that the indistinguishability of the water varieties was statistically significant. | 1 |
l2eafz | Biology | Charliehorses are caused by acid build up in the muscle tissue, but what causes your leg tendons to seize, so much so, it causes your anlkes to turn almost into clubbed feet? | I don't think the premise of this question is even correct. Charlie horses aren't caused by acid buildup... | 2 |
bb7w7m | Physics | Why is light the fastest thing? why that specific number | Basically what Einstein discovered is that not everything moves through time at the same rate and, in fact, your motion "through time" is related to your motion through space such that the faster you move through one, the slower you move through the other. This is why an observer of a moving object will perceive the moving object as "aging" more slowly than the observer. A way to (roughly) visualize this is to have a graph with x-axis and y-axis representing movement through space and movement through time (respectively). Grab a string and pin one end at the origin, fixed. You can then move the other end around freely, but it'll always be a fixed distance from the origin. If you point the string straight up, that's maximum movement through space and minimal (zero) movement through time. If you point the string straight to the right, that's maximum movement through time and minimal (zero) movement through space. Most things are very nearly, but not quite all the way, pointed to the right. Another consequence of Einstein's discovery is that things without mass are basically forced to move as fast as possible through space, representing the string pointing straight up. They do not "age" and are going at maximum possible speed through space. This speed is what we call the speed of light. It really doesn't have anything to do with light specifically, as any massless particle will travel at this speed. It's just light is readily available, easy to experiment with, and the first thing discovered to be moving this speed. The seemingly random or arbitrary value is simply because we developed our units of measure before discovering this speed. They weren't designed with this maximum value in mind. | 2 |
6yxbz5 | Biology | When my body is itchy. What is really happening? & why does it feel so good to scratch it? | Itching (ie pruritus) is often caused by an irritation of skin cells or the nerve cells around them. They can also arise from "misfiring" or "crossed" signals from nerve cells (sensory cells). Scratching helps an itch because it sort of stops the "itch" signal from transmitting and transmits a different signal (scientifically, scratching inhibits the "itch" signals from transmitting) - in this case a mild pain signal. These pain signals are sent along something called the "spinothalimic tract" which also carry signals for temperature and touch - which can be linked to pain sensations. It's actually pretty interesting research if you are to delve into it that was done at the University of Minnesota. My knowledge could be outdated as it's been a while but this is what was taught to us while I was in school. | 3 |
e84u3u | Technology | Why are movie audio volumes so different from action scenes to talking? | Most of the time, this can be a result of an audio format your system is not decoding properly, losing the majority of the voice track. A better decoder (receiver) will address this more than additional speakers. However, sometimes it is just simply inferior track mastering, or levels intended for movie theaters rather than optimized for home playback. | 4 |
cmlxs0 | Biology | how are some materials not good for the planet when literally everything here was created from materials from the earth? like plastic, i’m not sure how it is made. but i know it comes from elements on this earth so how is it bad if it’s from here? | It's made from petroleum which is found way underground and does no harm to anything. Bring that up, make it into plastic that wont degrade for thousands of years and do that in millions of tonnes and you have a problem. Take that same petroluem and refine it into gas, run it through a motor and watch that CO2 fill the atmosphere. Coal is really just carbon that holds a lot of CO2. Burn that and that same CO2 has a negative effect on the atmosphere that we live and breath in. Not all things natural are good for you or the planet. | 3 |
e86zu8 | Technology | Battery life I just went out to buy some 9 Volt batteries because the fire alarm decided to be my alarm clock today and tell me, quite loudly, it was hungry and needed more batteries (/s). I replaced the battery and went to go pick up some more batteries for when the other fire alarms require replacement batteries, and I had thought, if those batteries stay in the package for an extended amount of time, will they still have the same amount of life in them as when i first bought them? Or will they lose power and life, even though they are sitting in a sealed package? | Batteries slowly die even when in their package. I don't feel qualifies enough to explain why but I think it has sth to do with their internal resistance. | 2 |
6hz8os | Economics | Why are there so many different cryptocurrencies? | Because there isn't a single one that is universally accepted or endorsed by any government. This means that each person and business can choose to use and accept the currency they want and are under no obligation to accept any of these currencies. So the market is set up so that multiples currencies are able to compete with little incentive to unify under a single currency. | 5 |
5tiybk | Biology | How is it that animals in the wild are able to eat hooves, beaks, bones and other 'hard' body parts with seemingly little to no effect? I've seen documentaries of snakes, seals, whales even some spiders chomping away certain animals whole with fur, horns and everything and just casually walk away. Yet I struggle to swallow a carrot that hasn't been peeled. | Most animals can't eat that stuff and it will be left by the first group of predators and scavengers. Others will swallow it but it will be passed undigested through the system. Others will bite and chew it to expose as much of the surface so that special enzymes and acids can digest it. | 1 |
6zoovu | Economics | What does it mean that something is "tax deductible" and why does it matter? | While you didn't specifically ask this, there are actually three kinds of deduction-like things in the US tax code (not counting another set for business income)... Straight-up deductions are cases where some of your income is exempt from income tax for various reasons because you spent it in certain ways. These include mortgage interest, property taxes, state income taxes, charitable contributions, and the like. These only help you when in aggregate these exceed your "Standard deduction", which is a set amount that everybody gets. I.e. you can't contribute $1000 to charity and get any tax benefit if that's your only deduction. "Adjustments" are deductions that apply on top of your standard deduction. These include student loan interest, HSA/IRA contributions, moving expenses, etc. These all are subject to various rules about when you can qualify for them; many people might make too much money to claim them in some cases. "Credits" are even better than these deduction-like things because they count as tax payments, not just reductions in your taxable income. A $100 deduction might be worth $25, but a $100 credit would be worth $100. Credits tend to be for things like children and child care, college tuition, home solar and electric cars, and the ever-population Earned Income tax credit. A few of these credits are even "refundable", meaning they can not only eliminate your need to pay federal income tax, but you also get money back in the process, a so-called negative tax rate. You also can qualify for one or more personal exemptions, which is another deduction-like thing for each person in your household you support, like children. | 2 |
7517pn | Chemistry | How are Nuclear Missiles Safely Decommissioned? Say during a nuclear arms treaty that states reduces the number of nukes they can have. How exactly are the nukes 'disarmed'? | There's disarming the missile, which is removing the solid rocket fuel and recycling the aluminum skin. Then there's disassembly of the warhead. As others point out, that is done by separating the electronics package from the high explosive (which is burned) and taking out the nuclear pit. It would be stored, or mixed with lower concentration U-238. The US does all warhead disassembly at the Pantex plant near Amarillo. Fissile material is stored at Y-12 in Oak Ridge. URL_0 | 8 |
c13ba1 | Biology | What is a bone marrow transplant? Do they suck the marrow out of each bone and inject new marrow back in? | Not quite. Before the recipient gets the new marrow, their defective marrow is destroyed using radiation or chemotherapy. It used to be that some of the donor's bone marrow is extracted from the pelvis using a large needle, but now the more common method is something a called peripheral stem cell transplant, which is less invasive than extracting marrow from the pelvis with a needle. In a peripheral stem cell transplant, the donor is hooked up to a machine using a simple IV. The machine filters the donors blood and removes hematopoetic stem cells (stem cells that will produce all types of blood) while returning everything else back to the donor. Then these stem cells are injected into their bloodstream of the recipient. From there, the cells will circulate and make their way to the recipients bone marrow where they will proliferate and being producing normal blood cells for the recipient. | 3 |
bzz7ad | Biology | What happens to stomach acid once food is ready to move to the next step of digestion? How does the body dispose of it without causing harm to itself? | The acid moves with food but the pancreas secrete a bicarbonate solution to neutralize the acid so the food can be digested without making wholes in the intestine. Also digestion occurs in an alkaline environment. And then you just kinda poop it all out. (Minus nutrients and water etc.) | 2 |
74x1sk | Other | What are all those pop ups about binary trading options etc? Are they viruses/phishing scams? | They generally aren't viruses. A goodly proportion of them are scams. Certainly the testimonials are generally fake. Binary options are a sort of bet that's for some reason not regarded as actual gambling. I'm serious: they represent a bet that a stock (usually, though there's no reason you couldn't do it with other market abstractions) will close within a certain price range at a certain time. They're called binary because there are two outcomes: either the target closes in the predicted range, and the option pays out (either in cash or a pre-specified asset), or it doesn't, and the option is worth nothing. | 3 |
kko7nv | Engineering | Why can phones run games without active cooling or a real heatsink but leaving your desktop CPU uncooled is a terrible idea even when idling? | Your computer is hilariously more powerful than your phone. Your desktop might as well be considered a rocket ship compared to your mobile phone being a race car. Rocket ships can do amazing things and go incredibly fast, but they need a lot of support to turn on those huge engines. Racecars can go pretty fast and get you around things you need to do day to day and do it well, but it's never going to the moon, but it just keeps chugging on without a lot of maintenance or extra work to keep it going. | 3 |
bbm419 | Physics | How do they determine the speed at which extinct animals used to walk? I just saw this post about ancient human’s footprints in Australia and that they ran at great speeds. I wanted to know how they determined the speed at which he used to run. Link to post: URL_0 | This was actually explained in the original post you linked to. It's determined by the depth of the prints across their length, and the distance between the prints. If a print is deep, it means the impact was heavier; if there's a long distance between prints, it means the creature was going faster. This is all based on an assumed height and weight of a creature, which can in part be determined from fossil records. | 1 |
cfu2pv | Technology | why don’t companies do their sensitive work on computers that are not connected to the internet, and therefore unhackable? | I used to work for a company which did a lot of UK government work and most of their systems were IL3 accredited - essentially each contract required its own separate and secured entity, but could have limited network interconnection using VPNs over our internal non accredited network. There were loads of controls and cost quite a lot to manage, maintain and get audited on a regular basis. We built an IL5 accredited environment which had secure cages within a hardened room that was designed as a faraday cage with things like anti drill walls. I understand they had to do something special with the power into the room to ensure isolation too. No outside network links, only accredited personnel inside, no removable media. If you worked on that contract, you could only do work in that room and couldn’t bring anything in or out. I wasn’t accredited so have no idea how the guys did patching, but I do know that they only ran the contract for about 18months as it was too expensive vs the contract value. | 8 |
6llnna | Culture | Why is the campaign to free Tibet so much more popular than the Tamil push for independence from the Buddhist majority in Sri Lanka that has claimed more than 100,000 lives? | The kindly old man Dalai Lama is a much better PR face than Tamil Tiger suicide bombers. The fact that Tibet is fighting global economic power China instead of an island nation many people couldn't find on a map helps visibility too. | 1 |
7lsl85 | Chemistry | How does sunscreen help protect our skin? | Sunscreen works by combining organic and inorganic active ingredients. Inorganic ingredients like zinc oxide or titanium oxide reflect or scatter ultraviolet (UV) radiation. Organic ingredients like octyl methoxycinnamate (OMC) or oxybenzone absorb UV radiation, dissipating it as heat. Some sunscreens protect us from the two types of damaging UV radiation: UV-A and UV-B. Both UV-A and UV-B cause sunburns and damaging effects such as skin cancer. Literally the first result on google URL_0 | 5 |
mi44mq | Other | Why can’t we pick up and use all of the trash in the ocean? | We could, but we would need to pay people to do that, and no one is willing to spend a ton of money hiring people to clean up the ocean on a level that would make a difference. | 7 |
j5fymb | Technology | How are scientist able to see atoms? | The best way to visualize atoms is through the use of an atomic force microscope. This consists of a needle that has been sharpened to a single atom at the tip. This needle is connected to some machinery that detects where the tip is in space. The needle is then moved across the surface in question, like an ultra-thin sheet of metal. Since atoms do not like being close to each other, the needle tip is deflected every time it comes close to the metal sheet. These tiny deflections are sensed by the machinery it is hooked up to and sends it to a computer. A computer then converts this to an image, allowing scientists to visualize atomic structures. | 1 |
i17s3x | Engineering | What makes bells different sounds/pitches/tones? I just went to a bell museum but all she said was the combination of materials. But she played music on a bunch of different ones. | Size, thickness, shape, and material the bell is made out of. An analogy might be to find glasses of different thickness and ping them with a fork. You can also fill a glass with water. The smaller amount of free area the glass has as the water increases, the higher the frequency/pitch. | 3 |
5rsy5x | Culture | If we are "Innocent until proven guilty", then why is the verdict "Not Guilty" as opposed to "Innocent"? | There is a difference in your plea of being innocent or guilty, and the verdict of being guilty. And there is also the question of who has to convince the jury of what exactly. Does the prosecution have to convince the jury the defendant is guilty? Or, does the defendant have to prove his innocence? The jury and society at large is to assume the defendant is innocent until the state proves beyond a reasonable doubt that the defendant is guilty. The defendant does not have to prove his innocence. One reason for this is the value that it would worse for innocent men to go to jail on a false claim than a guity man go free on a true claim. Both situations have pros and cons but in a society that does not want an abusive government (or other powerful people acting through the government) this is the arrangement we decided upon. | 17 |
9n53iq | Other | Why do animators usually draw their characters with less than 5 fingers? | Have you tried drawing a hand? It's a pain in the ass. You've got to get proportions right, and the fingers are so thin that it's easy to mess up, and that doesn't help when you have a production schedule you need to keep. So, many cartoonists, especially in the West and in children's programming, will simplify the drawing of hands by giving them only 3 or 4 fingers. It gives more room for error in drawing, since the fingers are thicker, the kids probably won't care enough to comment on it anyway, and yet they can still get the proper range of motion to perform actions like grabbing onto things. | 4 |
f52liq | Biology | - why is there "good" pain (like rubbing a sore muscle), and "bad" pain? Why do they feel different? | Personally I think of pain as the body’s way to signal that you’ve reached your limit, and sometimes pushing your body to the limit is what you want. Eg in dance school you should stretch to the point where it’s uncomfortable/painful otherwise you’re not getting any more flexible, but not beyond that because then you hurt yourself. | 5 |
5nl8dp | Other | What happens if the President of the USA wants to quit because people are too mean or the job is too hard? | > Does it really just go to the Vice President that easy? Yes. A president can voluntarily resign at any point. The VP becomes President and a new VP is nominated. That said I don't think this will happen. Pence is insurance. See all the things people are afraid of about Trump, Pence has more of. Trump may end up being a great leader, Pence is a fucking basket case. But if you remove Trump, you get Pence. Insurance. | 14 |
j4uo7s | Biology | How do lasers remove tattoos? | Not an expert, but from what I understand, the ink is broken down into very time particles which then get carried away into the blood stream and is then expelled out by the organs. | 5 |
dth029 | Engineering | Do cars still use gas going down hills? ELI5: This is a really stupid question, but suppose you’re in a car with all the AC off and you go down a long hill without hitting the gas. Does the car still use gas during this or is it “saving” gas? | No, they don't use gas going downhill. When the RPM goes high while the throttle is closed, the ECU will cut off the fuel supply to the engine. If your car has a fuel consumption meter you can observe that the consumption goes low during the cut-off. | 3 |
hht0xf | Chemistry | Where do smells go when they “go away”? Especially if it’s an enclosed space with no ventilation, and the smell eventually goes away. Where does it “go”? Edit: more specifically, how does it dissipate? A crude example: My husband destroys our bathroom. We unfortunately don’t have a built in fan in the bathroom. We just close the door so the smell doesn’t get into the rest of the house. In an hour, we open the door, the smell is gone. Where did the smell go? | Your nose doesn’t really detect smells per se. it detects changes in smell. The smell goes away because your brain has accepted it as normal now. This is a super simplified break down but hopefully it helps | 2 |
dvfk0q | Economics | How do mortgages work with inflation? Does your debt (as shown on paper) increase each year as inflation is applied? Do your payments you've already made also inflate when you receive a summary? Does your payment that you have to make go up with inflation each year? Is this what variable/fixed is, if not, what are those? | Your mortgage is not adjusted for inflation. That means, if you have a mortgage and inflation goes up, you're still able to pay back your loan with the depreciated money. Thus it benefits you as long as you have a fixed-rate loan and your wages rise with inflation. This is one of the reasons longer-term loans may have a higher interest. The interest rate covers not only the risk of the borrower defaulting but also the fact that towards the end of the loan, the money being used to paid it back will be worth less. If you have a variable-rate loan, the interest goes up and down with the fed's borrowing rate. In the case of high inflation, the feds may raise their interest rates making variable interest mortgages go up as well. In this case, inflation doesn't benefit the borrower. | 3 |
hf12a5 | Biology | Why cant we create a living being out of organic material if we know all the ingredients? I'm assuming that by now, we must be knowing each and every constituent of at least a simple unicellular organism - so why cant we making a living organism from just these ingredients? What is missing? | Organics weren't designed to be built, we evolved to GROW. In fact a major part of why organics turned out this complicated was so they could grow and make other organics. I'm not even necessarily talking about having a baby, you have to think about it on a cellular level. Every single cell has allllll the ridiculous amount of information needed to make more cells. When to do it and when not to, how to decide which type to make, and the hardest part - how to do it. In fact every single cell is not only capable of making other cells, it can do so *while still functioning*. My point is, if you're just gonna build something, why the hell would you go through all this trouble? And from another perspective, organics involve a lot of things just kinda floating about. There is a complete lack of structural integrity. Imagine being half-way done building a human leg. The meat just kinda wobbling about, the blood leaking out everywhere, it's a nightmare. Plus, everything would keep dying before you're finished because the other parts it needs aren't there. The point is, reproduction is literally the foundation of organics. The first organism wasn't the first object to move, breath, or any other definition of 'live'. No, the first organism was the first object that could reproduce. And this process is so fundamental to every single part of our design that we simply can't be made any other way. | 4 |
5sl5y6 | Physics | What causes the "singing" when you drive over bridges or certain types of asphalt at high speeds? | Does anyone know what the result is to the tire? Are these strips bad for the tire/wear the tire? Sometimes during construction, you are almost forced to drive on them for an extended period. | 2 |
9d3vtc | Technology | Why do solar panels stop working? According to a recent BBC article, after 30 years or so solar panels are end-of-life and the scrap is no good for anything but landfill. What stops them working? What makes the scrap unusable? | The panels on the voyager space probes worked for longer than 30 years. Higher tier panels in residential solar degrade at half percent a year and should still be at 90% of their output at year 20. Even if that curve is off a bit, that's still around 80-85% at year 30. Unless the article is looking at polycrystaline panels made 30 years ago? I must be missing some detail(s). Can you link the article? | 3 |
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.** | Lets start with a baseline: there is a city, and in that city people are **trading apples**. > How does buying and selling stocks work? If you want to buy an apple, you can walk up to a shop (a middle man, a broker) and ask them to buy an apple. The shop owner then gets apples from the farm or from someone else and sells them to you at the price that is agreed upon. If you want to sell an apple, you can set a price or agree to a price that the shop owner wants to buy your apples at. If more people want apples, the price goes up, as there is more demand and fewer apples. The sellers can ask more money. If less people want apples, the price goes down because they might be stinky apples no one wants. > What is short selling? You have an apple. Its worth $10 in your city. I walk up to you, and I tell you, let me borrow your apple. I will pay 1$ to lend it for every week I have it. You agree. As soon as I get it, I sell it for $10. I now have money and no apples. One week later, the price of apples goes down to $5. I buy an apple at $5 and give you your apple back. I've made $4 profit (since I paid $1 to borrow it). I have shorted apples. I have made money on the price of apples going down. If the price went up instead, and I was wrong, I lose money when I have to buy the apple back to give back to you. > What is a short squeeze? If tons of people in my city are shorting apples, but the price actually goes up (I was wrong) they are in trouble! The price could technically keep rising and their risk is infinite. Now if demand goes up, and people suddenly LOVE apples, those people that shorted get really really nervous. The higher it goes, the more it costs to buy back the apple (cover). When the first person that shorts breaks, and buys back apples, the demand raises, and the prices goes even higher! Now suddenly shorters are racing for who can buy back first, making the price explode like a bomb. > What is stock manipulation? People doing funky things with apples to wrongly give the illusion the apples are worth less. For example, they can lend out apples that they just borrowed from someone else, or say that there is a worm infestation when really there is not. Or they can close apple shops altogether, which would be really bad and illegal. > What is a hedge fund? Its like an apple king in your city, they have a lot of apples and/or move a lot of apples, making a lot of money in doing so. They have a lot of power to influence the price of apples to their benefit. | 489 |
jdco7r | Engineering | what do washers actually *do* in the fastening process? I’m about to have a baby in a few months, so I’m putting together a ton of furniture and things. I cannot understand why some things have washers with the screws, nuts, and bolts, but some don’t. What’s the point of using washers, and why would you choose to use one or not use one? | There are many other types of washers and reason you might use them - lock washers that prevent bolts from loosening on their own, rubber washers that act as a seal or dampener, inhibitor washers that prevent corrosion, etc... but in your case, with wooden baby furniture, it's about spreading out the load force. Grab a piece of styrofoam and try to push a finger through it. Pretty easy, right? OK, now try to push your fist through it. Same amount of strength, but somehow it's not as easy. Why? The force is being spread out across more material. That's effectively what a washer does - spreads the force of the screw head out across more material, allowing it to be very tight without just tearing through the material. Screws that don't have washers probably aren't required to be as tight. | 17 |
60uuol | Chemistry | How do relatively complex organic molecules like THC and nicotine endure combustion in a cigarette? | Complexity doesn't necessarily mean that a molecule can't withstand high temperature. According to [this]( URL_0 ) study there's no significant increase in the amount of nicotine byproducts up to 1000 C. Cigarettes don't usually get above 700 C during normal use, so there's very little chance that nicotine breaks down from heat alone. Looking at [this]( URL_1 ) picture of the structure of nicotine, you can see that it's mostly rings. Rings in chemistry are fairly stable, and double bonds (also present in nicotine) are also fairly stable. | 1 |
9tatdw | Engineering | Why do airplane black boxes have to be kept in water after they are removed from the sea? Following the latest Lion air plane crash, I saw a video of the black box being retrieved. Upon taking it out of the water it was immediately thrown and kept in a bin of water. | I'm involved in the marine side of black boxes (VDR) but the leading manufacturer of VDR capsules is also the leading manufacturer of the final recording medium of airplane CVR/FDR. & #x200B; Snipped from the accident data recovery manual: [ URL_0 ]( URL_0 ) | 7 |
5s0scb | Other | Why can we eat meat (like on bread(salami)) cold, but some meat only cooked? | Salami is normally smoked and that is a cooking process. Other kinds are boiled, and only a few are raw cured. But even those that are raw cured are prepared in such a way as to inhibit the growth of bacteria. Raw meat is not dangerous, the bacteria that grows on it after the animal has died is dangerous. Because we do not eat our meat minutes after we kill the animal we have to cook it for it to be safe unless we take extreme measures like we do with raw fish sushi. | 3 |
kkvcqh | Biology | why can't we have supplements or pills for dopamine, oxytocin, serotonin or endorphins just like we have melatonin or contraceptive pills? | An "overdose," of Niacin will be broken down into serotonin by your body. This causes what is called the niacin "flush." "No-flush" niacin has a time release to prevent the excess niacin that triggers the conversion. If you are on an ssri and run out, and are completely unable to get a refill for a few days, taking 500 mg of niacin (that isn't "no-flush") can serve as an emergency stopgap. The flush is very painful if you don't have a serotonin shortage. If you do need this emergency dose, it will be the most pleasant feeling of all the skin on your body being on fire you will ever experience. At least that was my experience. | 26 |
6pkylq | Culture | Why some Asian companies ask candidates to put their photo, weight, height on their resume? I've noticed when I applied this Korean company and they asked me to put my photo, my weight, height, birthdate, whether my parents graduate university, my grade in universtiy etc. I was just talking to my friend in China.. and she said it is pretty much same there as well. Why do you think they ask us to put those things in resume? Do you think it is vital info to sort out people based on whether their parents' went to university? Anyone works in HR for Asian company, it would be really appreciated, if you could explain whyyyyy | I know in Japan at least there's a fat tax and the companies are the ones that pay the fine if their employees are overweight, so makes sense they wouldn't wanna hire bigger people if they didn't have to. URL_0 | 2 |
8iofzl | Other | What is the significance of having to list Mothers maiden name when filling anything out? | It's something that you will know, but most people would not... so it's a uniform piece of data that can be used as proof of identification. | 21 |
bz1879 | Technology | How do you make an operating system? | With great difficulty. You have to start with the hardware, will it run on regular modern computer hardware or its own custom thing? You write code that will communicate with the hardware in a structured predictable way (usually assembly/machine code). You write it in a way that it can store and manipulate data. On top of that, you create a layer of abstraction, a way to communicate this information to the user... could be as basic as a couple of LEDs, by telling the hardware: "hey give 5v to this pin". It can be more advanced, like draw this on the screen (but that's it's own topic). Once you have that layer you have a basic OS, the first ones that use modern monitors simply had a text interface that would ignore commands it did not understand. | 4 |
6f1u50 | Biology | What exactly is the voice inside our head and why do we have it? | One controversial theory of consciousness is called the bicameral mind. It was explored in the recent TV show Westworld. Essentially, it says that consciousness developed from language. Once we had a spoken language, our brains formed a second level that spoke to the lower level and told it what to do. The animal brain did mostly what it was told by that higher brain, and presto, you have a basic system of consciousness. Our modern brains developed from there, and the voice in your head is the remnant of that bicameral mind our species once had. | 4 |
fj2pz8 | Chemistry | Why does fine powder (like flour or powder milk) mixes evenly when stirred in cold water, but not in hot water (where the mixture becomes lumpy)? | Most powders dissolve better in hot water because the molecules of water have more energy and are "bumping" into the powder molecules. Hot water molecules have more energy and move more than cold molecules. In some powders, mostly those that contain starches, the rapid mixing of the powder and hot water becomes a problem. The hot water immediately bonds with the outer layer of the bits of powder, but they form a shell which prevents water from reaching the subsequent layers of powder. | 2 |
kghcgn | Biology | Why does it feel better to sleep on one side rather than the other ? Eg. You feel more comfortable sleeping on your left side rather than your right OR you feel more comfortable on your right side rather than your left Edit for clarity | Internal organs, e.g. I've heard that due to gravity, the shape of the stomach, and the angle of the connection between it and the esophagus, sleeping on your left side can greatly reduce reflux. | 2 |
7gmqso | Other | What is the difference between time signatures that have the same ratio? For example, why would someone choose 2/2 time over 4/4 time? It will still give your 4 quarter notes per measure, just at half the time spent on each quarter note. | Its not always about the ratio, its mostly about where you want the emphasis to be and how fast that beat goes. Also keep in mind that in many 20th century arrangements composers will stick in measures with different time signatures to produce a certain effect, and those measures don't always behave the same as if an entire piece were written in that meter. Some time signatures are close to interchangeable. 2/4 is often really similar to 2/2 or "cut" time even though those aren't the same ratio as 2/4. Having the beats on quarter notes is a little easier to read for some musicians that haven't played a lot of the old marches written in cut time. Others are not. 3/4 is 3 beats per measure, each beat being subdivided into 2, while 6/8 is 2 beats subdivided into 3. 6/4 can mean a few things. If an entire piece is written in 6/4, it probably is in a slow 3. But if a random measure is in a piece, it may just represent a 4/4 + a 2/4 measure to extend a phrase by a couple of beats. In addition to 2 vs 3 feel, the composer arranger will take other things into account, like how much work would the conductor be doing, and how much effort is to write everything out. Going back to 2/4 vs cut time, the advantage of 2/2 is that really fast notes can be written as 16th notes instead of 32nd notes. That makes it easier to read and easier to write. | 6 |
kdts39 | Biology | I’m not diagnosed with anything but sometimes I take adderall and it makes me happy and/extremely focused with no side effects. Why could this be? | Those are pretty much the exact effects of Adderall on people without ADD/ADHD, it's why it is often sold to college kids for both recreation and study assistance. | 5 |
8b6356 | Physics | How does a relatively small amount of Plutonium/Uranium in a fission/fusion bomb translate to several GJ/PJ of energy in an explosion? | You have probably heard of Einsteins formula E=mc² : Energy is Mass times the speed of light squared. The "speed of light squared" part is a very, very big number. So if you manage to turn some mass into energy, you get quite *a lot* of energy. And a fusion or fission bomb does exactly that: A very small amount of mass is turned into energy - the Hiroshima bomb got its destructive power from turning about eight grams of mass into energy. | 2 |
6j3y5j | Other | What started/caused the Vietnam war, and was Vietnam equipped enough to have concocted and dispersed agent orange? I currently live in Turkey and there have been some bans on some websites (such as Wikipedia) leaving me with limited resources for research, so I thought who better to ask than my fellow redditers. | 1. US dispersed the Agent Orange, not the Vietnamese. 2. We started the war with a glass flag attack in the Gulf of Tonkin, giving us an excuse to invade the country out of fears the pro-communist faction fighting against the democratic faction may win. | 2 |
cctbbq | Physics | Why didn't bombers shut off thier engines and glide over their targets to be more stealthy? | That might be useful is sound was the primary way that the bombers was detected and sound have been used it was never the primary way that you detect bomber if you look at WWII. A bomber and in general all military aircraft are bad gliders so they would loose altitude quite fast. The best location to fly a aircraft to avoid fire from the ground is as low or as high as possible. Heavy bombers in WWII flew as high as possible so the could avoid the anti aircraft artillery. The they can be spotted by radar and search light and the sound is not relevant compared to speed and altitude. The turning of the engine was used and the Soviet [Night\_Witches]( URL_0 ) that flew slow biplanes of a old design. They did in night bombing raids against the germans flow low and slow and they turned of the engine so they could glide the final approach and drop the bomb with only wind noise from the planes. In low level night rides like that sound would be the first warning and then it could be useful. In other situation you like to have the engine on. | 5 |
m6srun | Biology | ! What is the difference between genetics, and epigenetics? My experience thus far has been in nature vs. nurture, and epigenetics sounds like it is a grey area in the middle. I am studying the effect of trauma on the ability to learn, and I can't get my head around this concept. I get genetics. I get experience-determined elements, but I do not get epigenetics. | Epi means above. It's a higher level of genetics which affects gene expression without affecting the genetic code itself. Environmental factors during the individual's lifetime cause chemical modifications to the genetic material. These modifications are basically markers, chemical groups that are stuck onto the chromosome, which have the effect of promoting, demoting, and disabling the reading of that section of the chromosome. This has wide ranging effects on the displayed characteristics of the individual, and epigenetic information carried in the gametes can also be passed on to offspring (i.e. trauma experienced in your lifetime can have an effect on your children). In the case you're studying, experienced stress causes cells in the body (brain, perhaps) to add markers to their DNA. These markers mean that some genes are promoted or demoted, and the proteins that are over- or under-produced have critical implications for cognitive function. Epigenetic information from the parents is 'nature' and acquired epigenetic alterations are 'nurture'. | 2 |
dfhwr9 | Other | Why does traffic come to a standstill during rush hour? If the front cars are going the speed limit, shouldn't traffic flow consistently at the speed limit? | it's in essence a ripple effect, First driver slows down (for whatever reason), the one behind it, reacts and slows down a bit faster and so on and so on. It might be a fraction of a second , but over a long enough distance, and time, it can cause cars to completely stop for a second or so, then by the time the car gets moving again the car behind it is stopped for longer, and so on and so on again... This is now a "rolling traffic jam" which moves in the opposite direction of direction of travel. This jam can be anywhere from a few car lengths to a few hundred car lengths long. As "rush hour" passes their are less cars so their is more distance between vehicles and so the ripple effect is broken and traffic moves as normal. | 24 |
h8pwfh | Other | Why are swear words bad? | I think there are three categories of swear words; body parts, sexual activities, and blasphemy type words (Jesus Christ when you're mad. or God damn, go to hell, etc.) These three are very personal and intimate. Oh, wait, there's also the potty words. Again, sorta taboo. You probably don't ask grandma if she just took a shit. We taught our kids there are two types of swearing; inappropriate and hurtful. If you're 12 and you're goofing around with your friends after school, saying, "Oh shit!" isn't a big deal. If you are in class and you say it, it is inappropriate swearing. In other words, it depends on who is with you and where. Hurtful swearing is bad swearing. Saying "fuck that" is one thing. Saying, "Fuck you" is another. Again, context. We also teach our kids that bigoted, hateful words against sexualities, religions, colors, cultures, etc., are never ok. My kids are almost 13 and 16 now and neither of them ever swears, by choice. | 1 |
knqp60 | Mathematics | Why is a “cup” of coffee 6 oz, but every other liquid is 8 oz? | Probably has to do with serving sizes. A “cup” of coffee is 6 fl oz Bc that’s about the volume a person normally drinks as a “cup” of coffee. It’s not really a standard measurement. I also bet that coffee and hot cocoa brands put “6 fl oz” as their serving sizes because then they can make it look like it has less sugar/caffeine than it really does. If you’ve ever noticed why Oreo cookies come in like 6 packs sometimes but the servings are like 2 cookies even though nobody would only eat two Oreos out of that pack and then leave it for the next time, that’s the same reason why. | 1 |
gwb10c | Biology | Why are humans so physically weak compared to other animals? | We have the best endurance of any animal. Not sure if that counts a strength. Sure a cheetah or dog can run faster than us but they’ll have to stop for a break. Humans can walk and outlast them. It was a tactic used for hunting historically too. URL_0 | 5 |
7hhqzv | Biology | Why do we take fever suppressors, like Tylenol, when we have a fever, why don’t we just leave the fever and let the high temperatures kill the bacteria? | [According to the American Association of Pediatrics, you should allow most fevers to run their course without medication as they are beneficial to fighting infections.]( URL_0 ) People take fever medications to make themselves feel more comfortable, whether it's because they need to be functional adults or because they simply don't like how fevers feel. They give their children fever medications for the same reason; parents especially do not want to see their children in pain. Fevers do not become dangerous until they are over 103 (in adults, the number changes for children and infants), at which point you need to *go to a hospital immediately*. Do not attempt self medication. As someone else in the thread mentioned, if the fever gets that high this is a sign of brain damage. Anecdotally, when I've taken fever medication I am sick for much longer than when I haven't. Granted, day to day it's more tolerable, but the sickness lasts for so long that it simply isn't worth it. I'd rather take a day or two off of work and let nature run its course. | 2 |
ltnhtc | Technology | How hard is it to hotwire a car? Like when you turn the key in a car, it completes a circuit right? How hard is it to just take the wire connected to the switch and touch them together? | It was pretty easy long ago or in older vehicles. Connect the ignition circuit, the one that completes the circuit for the coil/battery/alternator, and then connect the starter circuit that feeds power to the starter motor that initiates the system to those wires and it would start and run. [Three wires]( URL_0 ). Today's vehicles are much more complex and hot wiring one involves bypassing and/or feeding power to a lot more systems, some that are computer controlled and need an electronic signal from a computer chip in the circuit to work. Starting these involves completing a lot more than just the 'run' and 'start' circuits. Extremely difficult in most cases. | 4 |
jylfr2 | Technology | Sound in shows and movies, that goes from soft to loud and you have to keep changing the volume | Audio for shows and movies isn't generally mixed for TV speakers. Movies especially. They're mixed initially for surround sound where dialog and main sounds get sent to a center channel, and effects and other noises come from other speakers around the room. If you watch a movie on a 5.1 surround sound system that's tuned for your room, you'll find you won't really deal with this issue anymore. When re-mixing for a home release, they don't know what setup you're going to have, so they do what they can, but generally if you're using normal TV speakers, there's some software somewhere in the chain that's down-mixing the audio to just two (very shitty) speakers and it isn't doing a very good job. They aren't taking the time to go through the movie another 40 times listening to everything and manually adjusting volumes for a 7.1 mix, a 5.1 mix, a 4.1 mix, a 2.1 mix, a 2.0 mix, and a mono mix. They're just clicking a button in software to output a mix, and letting your (crappy) hardware at home deal with the mix. There is also the fact that in many cases, audio engineers for a show are very rushed, and don't have time to give an ideal balance in volume to every channel before shipping the episode. If you have some cash and feel like solving the problem, a mediocre AVR, a center channel speaker, and a L and R speaker will solve your issue almost entirely. Some TVs also have software solutions that work okay, like volume normalization, or "dynamic audio" or something, but it will depend on the model of TV you have. | 3 |
5vd30v | Other | How did Americans lose their British accent? I know that the British came to North America, and then settled there. But how did they lose their accents? | America is a melting pot. It is not merely a collection of English settlers. Many of the more unique features of American English can be traced back to pronunciations made by people who did not have English as a first language. Most famous is probably the influence of Yiddish on the New York City accent, but across the US the non-English speakers impacted the way English was spoken. In addition, there was already at that time significant variations in English pronunciation on the British Isles. West End Londoners (often the pronunciation we most readily associate with British English) were not a grouping that was greatly represented among immigrants. Most immigrants came from poorer areas, such as Ireland and Scotland. This has also left a mark on the pronunciation of American English. | 5 |
66wh28 | Biology | How do single celled beings "know" what they're supposed to do/"want" to do? | This is actually what I went to university for: Biochemistry. So all interactions on a molecular level are completely stochastic. What this means is everything that happens in a cell is random chance. Molecules just bouncing around and knocking into each other at random and then things happen. Now I know this comes off as a complete contradiction to everything you've learned in biology as a kid. Cells perform functions. They move towards stimuli. How can all this be chance and happenstance? But what if I told you to look at everything that happens in a cell at a lower level? If you think about it, the macro-molecules in cells responsible for cellular functions and interactions such as proteins and lipids don't have brains. Then how do they know where they need to go? It's simple, they don't. Molecules can't decide when and where to bounce into one another. But a cell is very clever and uses structures and concentration gradients to influence the random movements of these molecules. Structures are helpful by eliminating degrees of freedom from molecular movement. In layman's terms they restrict movement to make it less random. Imagine a pen, when you are holding a pen you can move it up, down, left, right, slantways, longways, backways, frontways, squareways, and any other ways you can think of. But what happens when you want to draw with that pen on a piece of paper? Now the pen can only move up, down left and right. By limiting a molecule's degrees of freedom like this you increase the chance that the thing that needs to happen happens. A train on a track is much more likely to reach a specific destination than a speck of dust floating in the wind. Concentration gradients are helpful because things naturally flow from high concentration to low concentration, and having more of something increases the chance that that thing will knock into something else. I can get into how regulation of gene expression can influence structures, but I'm out of time. The universe is an amazing chaotic place, I hope this helps | 5 |
cehrs6 | Other | Why is it so hard for juries to convict a police officer when they shoot an unarmed civilian and there is clear evidence of excessive force? | Well, there isn't usually "clear evidence of excessive force". Maybe the policeman thought the suspect had a weapon. After the encounter, a thorough search reveals no weapon, and now the force looks excessive. But, at the time the officer made the decision it wasn't so clear, and that "reasonable doubt" makes if difficult for a jury to convict. Many people seem to think it's OK to fight with police, run from police, or yell at police. This behavior is very dangerous, and when someone is acting in a dangerous way, particularly when the officer has body camera footage of the person posing a danger to the public safety, they can be killed with little likelihood that the officer will be found guilty of using excessive force. TL;DR: Do what the policeman says! The time for suggesting he was violating your civil rights is after the fact in a courtroom with everybody in their suits. That way everybody lives to get to make their point. Don't die of being dead right. | 3 |
fd0a2z | Mathematics | Lindley's paradox [ URL_1 ]( URL_0 ) | Ok, this is challenging, I'll explain the example on the wiki. We want to know if the probability of a newborn being male is 50% or not, we can do this in two ways. First approach (Bayesian or "a priori", i.e. before knowing the reality): I assume that the probability is in fact 50%, then I check the official numbers and see how well they fit this this assumption. Second approach (frequentist or "a posteriori", i.e. already knowing the real outcome): I take the official numbers and try to find out if they are better explained by one hypothesis or the other. The point is that the first approach will answer "yes, it's likely to be 50%" because it will find out that our numbers are a plausible result of that probability; the second approach will answer "no way that it's exactly 50%" because you can't make such a precise assumption (and, in our example, if you're giving such a bold explanation the better one would be that the probability is exactly k/n), it could easily be 51% or 49%. This is because Bayesian penalizes the "wider" hypothesis (if we say the probability is 50% is a very good hypothesis vs saying that it can be anywhere between 0% and 100%) while frequentist prefers it (it's infinitely more likely that the percentage is close to 50% than exactly 50%). Edit: god, this took 40 mins to ely5, I had to sacrifice precision a bit | 1 |
ay7kvv | Biology | “ What is happening when your eyes get heavy from lack of sleep “? | Muscles you use the most tend to get tired first, like for example, if you walk all day your legs will become fatigued. This also applies to the muscles around your eyes - your ocular and brow muscles become tired because you’re using them for most of your waking hours. Looking at a computer screen for a long time or having chronic allergies can compound the heaviness feeling in your eyes. | 1 |
cdl5pf | Biology | Do we already know or at least have a real theory about what is the logic behind thinking? How does our brain find an answer to a question before we consciously evaluate if it is legit? Sort of an "algorithm" of our thinking I was *thinking* about it a lot recently and only thing that comes to my mind is that depending on inputs our brain receives, it subcouncsiously sorts all of their associations and their associations and so on in a very very deep and complex way to get an output that we "hear" in our head and form an answer. But is there a real answer to this or something that we could say it is "most likely" an answer? Sorry if this is a silly question that can't be answered, but I am legitimately curious. | TLDR: A brain is *very similar* to a circuit board. It receives input and produces an output. However, every time a brain produces an output it changes; giving the same input twice does not produce the same output twice. Your mental voice is a result of electrical signals in your brain. But we don't know everything that goes into creating or controlling those signals. Your brain does a lot of work before a thought can be "heard" in your head. ======= Your question can sort of be answered, because a lot of this is still (very reliable and treated as truth) theory. I'm a medical student, not an expert. \[facts\] Your brain has cells which are called neurons. Each neuron has an input end and an output end. The neuron can receive input from hundreds of different neurons, and can send an output to hundreds other neurons. When a neuron receives an input, it builds up a charge. If the neuron builds up enough input charge, it passes on signals. If a neuron receives lots of charge, it will pass on stronger signals and to more neighbors. If the neuron does not receive enough charge, it doesn't pass on any signal at all. With this, the neurons form very complicated, overlapping, interwoven chains and loops. If you send the same strength charge to the same neuron, you usually activate the same chain which creates the same output. HOWEVER, every time a neuron sends a signal out it physically changes so that it becomes more likely to send the same signal again in the future. Since every neuron in the chain moves just a little bit, the chain is never exactly the same twice. Every thought you think changes the chains built inside your brain. This means that parts of your brain develop patterns, so that an input signal gets "processed" into a similar output. This is why you have a Brocas Area in your brain, which is very strongly linked to "thinking about how to say something." That's a bit misleading, because people who are mute cannot speak, but the Brocas Area still activates when they think about "speaking" in sign language. So your brain has an "area" that is used to "process" information relating to "expressing my ideas in a way that another human will understand." \[theory\] So when it comes to the voice you have in your head, most of the mechanisms are physical and chemical. There are physical chains of cells that activate in a specific pattern, and the pattern is the result of habits of thought you have developed over time. Does that mean that two physically identical brains would produce the same output if given the same input? Theoretically, yes; but no two brains will be identical, so we can't actually test this. Does that mean that consciousness is just a pattern of chemical reactions inside a brain? Theoretically, yes; however, science is limited, and it might be more than this. Does that mean that brain surgery results in a consciousness that is fundamentally different than it was before the surgery? Theoretically, yes; but lots of people come out of brain surgery and are perceived to be the same as the person who went in. Is it possible for a technology to wirelessly induce electrical signals inside of the brain that results in the cascading neuron activation that is thought? Theoretically, yes; in fact, there are already implants that do this in a limited way, but just because a machine can simulate thought does not mean that thought is only a machine. ======= EDIT: Your brain also has an area referred to as the prefrontal cortex. This area is used to "simulate the world and predict a consequence." If I ask you what would happen if I stabbed myself with a pen, your prefrontal cortex would activate, simulate the ideas of \[person\], \[pen\], \[stabbing\] as input and produce \[bleed to death\] and \[idiot\] as an output. These outputs are the result of patterns inside your brain. Those patterns developed based upon your life experiences, the inputs you have collected and the residual pattern of chains inside your brain. This is why some people, given the same question above, would produce outputs like \[blood and gore is cool\] or \[a person who stabs themself needs therapy\] as outputs. They have different neuron chains in their brain. A person who has never seen a pen would be unable to simulate that question. They don't have enough input to process the simulation. But they could probably guess at the outcome because stabbing almost always results in bleeding, and that neural chain will make up for the missing pen chain. | 2 |
72n5ql | Other | How does TV works in the US with that hour delay? LA is 3hours earlier than NY. In France, TV shows start at around 9PM. How do they air TV shows in the US without a coast watching late in the day or early at night? | News and scheduled programs have different airing times for the different time zones. Live programs (sports, or a presidential debate or something) are scheduled so as to attempt to be convenient for everyone. This often ends up being rather late on the east coast, and inconveniently early on the west coast. I don't know how Hawaii deals with it! | 3 |
ersrrr | Chemistry | because fish oil is so good for you, why don’t we use it for cooking? | As others have stated, the omega 3 will break down in heat, thus removing most of the health benefits of fish oil. But also : An important factor in cooking with oil, is where the smoke point is. This matters for both taste, and health (cancer risk!). You want to cook with oils lower than the temperature that they smoke at. Thats why you don't (or shouldn't) fry in olive oil, etc, but instead use peanut oil or other oils with a high smoke point. URL_0 | 7 |
des2ab | Other | How can I help my daughter not worry about what is after life | Best option would be to explain that worrying about the future makes you miss what is happening in tbe present. After all, they can't enjoy life if all they worry about is death. | 1 |
728eh9 | Technology | How is Linux more customizable than other operating systems? | First off, I'm sorry people over at /r/Linux were rude. Pretend you'd like to change a meal you eat every day. Microsoft and Apple don't share their recipes, they want to keep it secret, and you have to buy the meal as is without knowing how its made from the store pre-packaged and you just have to eat it the way it is. Linux comes along and not only shows you the entire recipe, how its made, but gives it away for free, with so many options its a bit annoying. That's the simplest explanation I can think of. | 27 |
cnhw0o | Biology | Why do humans unconciously lift heavy weights with their backs, although a) leg muscles are stronger and b) it would be healthier? English is not my first language, sorry if my question is not easy to understand. EDIT: Thanks for all the answers first! While thinking about this, I personally also figuered that there‘s some kind of societal pressure too. Imagine for example dropping your keys and then doing a full squad to pick them up. It would look hilarious and most people would just bend over to pick them up. Although in this case, it is no ‚heavy‘ lifting in that sense.. should‘ve maybe left it away in the title.. | If you watch small children squat down and stand up or attempt to lift a box of toys (or even a large toy), their mechanical form is often excellent. I would suggest that "lifting with the back" or, more formally, using incorrect form for any given lift, is either learned or a direct result of laziness. Straight-legged deadlifts are an exercise that I train in the gym because it trains the hamstrings. Like any other exercise (especially weight bearing) it requires practise and correct technique. I've had lots of other gym goers come and try to "correct" my technique until I explain what I am doing. TLDR: "Lifting with your back" is not necessarily bad but is often used by the average person at the wrong time for the lift they are trying to achieve. Edit: Not the best video but the fastest one I could find [Child lifting naturally]( URL_0 ) | 4 |
5vwc6i | Biology | What would happen if you gave antidepressants to a person without depression? | Hi. Long time user of antidepressants here. To truly ELI5: Taking antidepressants (SSRI) has an effect kind of like focusing a camera. There is a "sweet spot" where everything is in focus (not depressed). If the serotonin levels are above or below that depression occurs. Antidepressants boost the effect of the serotonin present. If it's already at the correct level, it may be pushed beyond the sweet spot and cause problems. Therefore, if a person who didn't need antidepressants took them, it may cause depression. Of course, the real world is not so clean cut and actual effects and side effects will vary from person to person. | 12 |
94d9p5 | Chemistry | why does the foam from a fountain soda start to disappear when touched by your finger? | the oils on your finger, so if you do it, its ok, like sticking your fingers in your mouth. if someone else does it to your drink, to "help" you- they are being jerks and "tainting" your soda, and don't even know it. | 6 |
nyduix | Biology | Why Do Doctors Hesitate To Increase Voltage While Applying Electroshock to the Heart? I guess I'm talking about defibrillation. Is it just the movies, or is it how defibrillation actually works in real life ? I mean, you are trying to revive someone, trying to bring them back to life. What's the worse thing that can happen ? Why do they start from low voltages and increase it slowly, and get more and more anxious and dramatic every time they say "Go up to 350" or whatever. I mean, the person is already dead. What's the risk ? Why do they act so hesitant ? What's there to lose ? | The general thought is that using the lowest level of energy to convert the heart from ventricular fibrillation, ventricular tachycardia or atrial fibrillation to a normal rhythm is best. The idea is that the greater the shock, the greater the risk of creating a parasympathetic nervous system discharge that can theoretically prevent the heart from restarting. When portraying these types of situations, TV and movies often take liberties with medical accuracy in attempt to create tension or drama. Cardioversions for certain abnormal arrhythmias are very routine procedures that aren’t particularly dramatic. Cardiac arrests however can be quite dramatic, extremely emotional events when we are working hard to save someone’s life. Factor in things like a patient’s youth, an unexpected negative event, or an emotional connection you have with the patient or their family and the adrenaline gets pumping rapidly. So yeah- we will not hesitate to escalate the shock energy when indicated and tv doesn’t always show things the way they happen in real life. | 4 |
5qp32o | Other | In a democracy, what is supposed to stop hypothetical 90% majority from literally killing off minority 10%? My first thought was the Constitution. But leaders elected by the majority can amend constitution and make new laws. So, ultimately, what stops majority rule from killing off (or persecuting) the minority if it was so inclined to? In other words, is there any *moral obligation* ANYWHERE in the tenets of le democracy? | This is exactly the question that Muhammad Ali Jinnah asked the world at the time of Indian independence. He asked, should Indian Muslims trade domination from colonial Britain for domination from Hindu "caste Indians" (Brahmins) in the new nation of India? Jinnah, the secular political leader of millions of Indian Muslims, answered the question with the creation of modern Pakistan. | 14 |
mp4qbn | Engineering | How are damns built? Wouldn’t the water just crash down on the builders? | They build a “detour” for the water while they’re working on the dam. Then, they drop in landfill in the main river at the entrance and exit of that detour, and drain the water remaining between the two landfills. Then they build the dam in the now dry section of river and remove the land fill and the detour when done. Sometimes they leave the detour. | 2 |
6lhz3n | Other | What's the difference between a hotel, motel, resort and inn? | In general, a hotel is fully enclosed and has the doors to the rooms open into an enclosed hallway, intended for long stays with the associated amenities. Motels generally have the rooms open up to the exterior of the building and are meant to house driving travelers overnight. A resort is essentially a big hotel that is also it's own destination, with activities, spas, etc... And an inn, I suppose, would be more indicative of a very small motel meant for travelers to spend the night. These are not air-tight definitions, by any means, but those are the general understandings behind the terms. | 3 |
eqwflw | Physics | Why does the Archimedes crown work? I would have thought that any object of the same size, no matter the material would displace the same volume of water because its the same volume of object. Why does the heavier crown displace more water? Unless I've just completely misunderstood it | It was a matter of comparison. Gold is very dense, so the king gave lets say a kilogram of gold. At the end the crown still weighed 1kg & #x200B; So Archimedes takes 1kg of Gold from another source and puts it in water. He then takes the crown and puts it in water. If the crown displaces a different amount of water than the equal weight in gold then someone is cheating and stole some gold, replacing it with another metal inside to equal out the weight. Someone can cheat to make the weight match or cheat and make the volume match, but you cannot do it in such a way that you match both if you stole some gold. | 3 |
a06w4x | Chemistry | If cooking a protein would mess its structure, how does the body use it as a nutritional value? Sorry for bad english | Our bodies break down proteins into their amino acid components, then use these amino acids to create proteins specific for our bodies and our bodies needs. Cooking or heating a protein otherwise typically makes it non-functional, but it’s nutritional components (amino acids) are still there. | 2 |
912x9x | Culture | Why are MLB managers and coaches the only ones in professional sports to wear team uniforms? | Managers and coaches are allowed to be on the field to give instructions and to argue with umpires, which is not allowed in other sports. This, and the reason that they are also allowed to play, is why they wear uniforms. | 2 |
mbk01e | Other | Why are there no B batteries? | There are B batteries. They're rare, but they exist: URL_0 | 1 |
7bgtnq | Culture | What exactly do film critics mean by a movie "having heft", and how do directors make movies have this quality? | Stems from the slang term "heavy" meaning emotionally dramatic. A movie having heft means that it touches on emotionally dramatic events, like murder or rape or divorce. A movie that is poorly paced or doesn't connect the viewer with it's characters might not be able to justify it's heft. I've even heard movies that do this described as "overweight", as in, the subject matter is too heavy for the movie to be believable. A director, as the chief creative influence on a production, affects this on every level. The most important of which is likely casting and direction of talent. Choosing the right people who can really make something believable, and guiding them to be consistent with your vision is an essential part of directing. Other than that, every aspect of the movie aids it's believability. Even holes in production that the audience can see through, poorly planned special effects, bad CG, etc. can take a viewer right out of "the zone" and draw attention to the production quality rather than the story. Hollywood movies largely try to be "invisible" - the goal is for the viewer to be able to forget they are watching a movie and become emotionally invested in the story. There are a million and one approaches to the intricacies of how this is done but that is the general idea in how a movie can justify it's heft. | 1 |
ihyw54 | Biology | overwhelmed tastebuds Radiation treatment for cancer in my tongue killed my tastebuds. Now when I eat, in the first few chews of the first mouthful I can taste a bland facsimile of what I know the food is meant to taste like, but after that, nothing. I might as well be eating cardboard. My oncologist said that my tastebuds are being overwhelmed, and I didn't ask the obvious follow-up questions: what does that mean, and what is actually happening to my tastebuds in that instance? Cheers | Don't know why this happens, but I did hear about this guy Ryan Riley who creates recipes for people who have lost their enjoyment of food in this way: URL_0 I hope you can enjoy food again soon! | 1 |
gu65u1 | Technology | Why was yesterday's launch considered the first manned mission since 2011 when there have been many manned missions to/from the ISS? | SpaceX is the first private company to successfully launch a manned mission to the ISS. US astronauts have gone up with other countries' spacecraft, making it the first launch from US soil in many years. | 3 |
5uc00c | Chemistry | What are the benefits/drawbacks to certain products being made "from concentrate". For example, dish-soap. Some are made from concentrate and others are not. The same goes for food items like juices, which also are/aren't made from concentrate. What does the addition/subtraction of "concentrate" do to the effectiveness of the product? | It depends on the product. Concentrate normally means they've taken water out of something to make it 'stronger'. For cleaning products, I suspect it is marketing. The thinking with that would be we assume and associate concentrate with with being stronger, so a concentrate cleaning product must be X times better than a non concentrate product. For juices, again it can be marketing. **NB**:Where I live, juice from a supermarket has no concentrate. If it did, it would be a fruit *drink*, not fruit *juice*. A fruit juice has 100% fruit juice, a fruit *drink* has some fruit juice (usually not much) + all these additives, sugar etc. In this context concentrate means they have taken some water out of the juice to make it stronger. They've then put some of this concentrate juice into the drink along with other things to make a new fruity drink. Another possibility (common in fast food joints), concentrate means they've taken some water out, transported it and added water back in, all to cut down on transport costs. In McDonald's (again, at least where I live), they link the concentrated drink, whether it be Coke or juice, directly into the [dispensers]( URL_0 ). The dispenser also has a water hose and when pressed there is some ratio of water to concentrate that is supposed to come out. | 6 |
i0mjys | Technology | why is 3D printing such a big deal? | Data to make a part is much, much easier to move from place to place and share than actual low-cost plastic parts. That means more design flexibility, less up-front tool and die cost, less inventory investment and management, and quicker response time to get a replacement part. | 3 |
66zkaf | Chemistry | Why do antidepressants cause suicidal idealization? Just saw a TV commercial for a prescription antidepressant, and they warned that one of the side effects was suicidal ideation. Why? More importantly, isn't that extremely counterintuitive to what they're supposed to prevent? Why was a drug with that kind of risk allowed on the market? Thanks for the info Edit: I mean "ideation" (well, my spell check says that's not a word, but everyone here says otherwise, spell check is going to have to deal with it). Thanks for the correction. | Depressions is a chemical imbalance in the brain. Antidepressants try to correct the balance. Sometimes it changes the chemicals in the brain too much or too quickly which is hard to adjust to the changes. | 65 |
dn1jgz | Biology | Why is it harder to swallow a pill or tablet than a piece of food the same size or bigger | Because the pill or tablet has been chewed and covered in slippery saliva, so it’s dry and not as smooth going down. Edit: HAS NOT been chewed. You chew food and it mixes with spit so it gets all squishy and slippery and goes down easily, pills just get swallowed. | 9 |
5x4xhe | Biology | Will a more obese person burn more calories with the same daily activity as a thinner person strictly because of the amount of effort necessary to keep up? | My slightly overweight wife and her obese mother joined Weight Watchers together. WW gave her mother twice as many "points" because she would have to eat much more just to keep herself going. | 12 |
gjia2j | Biology | Why can we sometimes sense when someone is watching us behind our backs? | Your brain processes a lot of sensory input without you actively monitoring it. Sometimes the most reasonable explanation for multiple sensory measurements, even without visual information, is that someone else is there. If enough senses are triggered, it's only natural that you should confirm with what is probably your highest resolution sense. | 7 |
ikjkkf | Economics | What does Tesla’s stock split mean and why is it good? | It makes stocks more available and more affordable. Let’s say you have a company, with 1000 shares on the market, and each is worth 100 dollars. If the company were to split that at say a 4 to 1 ration, that would mean there are now 4000 shares, each worth 25 dollars. This increases the overall number of shares, making trading a bit easier, as well as lowering the amount of money needed to buy in, someone who couldn’t afford one share at 100 dollars might now be able to afford one or two at 25 dollars. | 3 |
f1vo8e | Technology | How did insane conspiracies spread before the Internet? How did absurd and ridiculous theories spread before the days of the Internet or Social Media? | People rote pamphlets and passed them out. People are still doing this. People wrote books, e.g. saying Space Aliens built the Pyramids, and sold a bunch of copies. | 2 |
j2hn48 | Economics | What are Stocks | > What are they? Stocks are, in essence, equal portions of a company. When you buy a stock, you're buying a part of that company. If a company has 1,000,000 shares in existence and you buy 1 share, you own 1/1,000,000 of the company. Usually shares come with rights, such as voting rights, as well as the right to receive dividends, which are payments made to people who owns shares from the company. > Also, how do you invest in something that’s not yours? Well, once you buy shares, they are yours. It's exactly the same as when you buy something at the store. Once you buy it, you own it. > Why are they so valuable? If a company is really successful, it'll make a lot of money. This means the value of the company will go up because people will be willing to pay lots of money for shares in that company. Not all shares are valuable, though. They can go up and down in value. > What are stock brokers and traders? Stock brokers are the people who buy the shares on your behalf. You give them a call, ask them to buy X number of shares in XYZ company, and they do it for you in return for a small fee. The nature of brokers, however, is rapidly changing. Stock traders are people who buy and sell shares. Some buy them with a view to sell them soon afterwards for a profit, while others buy them and then hold onto them for years, maybe decades. > Is it easier to get into them then you think? I have no idea how easy you think it is, and am therefore unable to answer this question. | 2 |
moi8jf | Mathematics | How do people find digits of graham's number? Like what the heck how do people know. It ends with 7, but hOw do people even know that? What's the mathematics used to even figure out such a number? | The exact method depends on what kind of number you're trying to calculate, but here's an easy to follow example. Suppose I want to compute the last digit of the number 3^(3723139463824547766) (the exponent is just your username, interpreted as a number in base-36, so it's effectively random). This number is absolutely enormous: the *number of digits* in this number *itself* has 18 digits. But if we think about powers of 3, it's actually relatively easy to figure out. If you write out the powers: 3^1 = 3 3^2 = 9 3^3 = 27 3^4 = 81 3^5 = 243 If we continue this for a while, we notice a pattern: the last digits go **3, 9, 7, 1**, *3, 9, 7, 1*, 3, 9, 7, 1... If we think about this a bit, it's easy to tell why: if you write out multiplication by hand the way you did in elementary school, you'll see that only the units digit of the things you're multiplying ever affects the units digit of the output. So in effect, by multiplying by 3 at each step, we're really computing ...3\*3 = ends in a 9, and then ...9\*3 = ends in a 7, and then ...7\*3 = ends in a 1, and then ...1\*3 = ends in a 3 again. In other words, if the power is a multiple of 4, the last digit will be a 1. If it's not a multiple of 4, we just figure out how far off it is. As it happens, the exponent we actually have, 3723139463824547766, is 2 more than a ~~power~~ (EDIT: multiple, sorry) of 4. So the pattern around it goes ...1, 3, **9**, 7, 1, 3, 9, 7... In other words, 3^3723139463824547766 ends in a 9. ---- Graham's number is computed through a similar sort of repeated process, so this kind of logic can be applied there too. | 1 |