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lt89fu | Biology | why isn't forest predators, like tigers and lions, fur green? | Unlike humans, the animals that tigers normally prey are red/green colourblind, which means they cannot distinguish between reds and greens. To their eyes, the tiger is perfectly well camouflaged. | 6 |
7kfhw4 | Engineering | Why do products that claim to block radio frequencies from cell phones actually increase your exposure to radio frequencies? According to the new California Public Health [guidelines]( URL_0 ) on reducing exposure to radio frequency energy from cell phones, you should avoid "products that claim to block radio frequency energy" because "these products may actually increase your exposure." Why is this the case? Does the phone actually "work harder" to stay connected if there's a blocker in the way? | The short and simple answer is that a cellphone will, to preserve battery, never use a transmitting power that is higher than necessary. Kind of, why the heck shout if you can whisper? If you install a blocker, you'll end up making it worse for the phone to communicate. And the obvious response from the phone is to transmit at the highest possible output in an attempt to reach through. That said, a directional shield *might work* without making the phone scream its lungs out, but that also requires that you ensure that the blocking direction is not the same direction as the cell tower. | 4 |
gq4tps | Other | Is there a term for when a person is about to sleep and they begin to think about negative past actions? Also, why does that happen? I'm just curious since it happens to a lot of people, myself included. | Yes there is actually. It's called "being human". You may also hear it bring referred to as "being conscious", or "having a pulse". | 2 |
7g6btr | Chemistry | If microwaves heat food by vibrating water molecules, then why do some ceramic bowls get 10 times hotter than the food they hold when they have no moisture inside them at all? | Microwaves, the waves themselves, have a width and oscillate. This causes polar molecules below certain sizes to oscillate with them. Water happens to be a properly sized polar molecule, but it is not the only one which experiences the oscillation. So depending on the composition of you're dish, there may be other molecules affected by the microwaves. Hope this helps. | 2 |
7glsb3 | Technology | Why is Random Number Generation so important for IT security? As far as I know the primary application of RNG algorythms in IT is security algorythms such as hashing and encryption. Play Station 3 was hacked basically because some number wasn't truly random. How exactly does the ability to predict "random" numer compromise security? | I'm thinking of an ATM PIN. What number am I thinking of? If you can guess it, you can access my checking account. It's like guessing a password. If I use a system to generate my ATM PIN that seems random, but can actually be reproduced (like taking my birthday and scrambling the order of the digits), someone could figure out the system I use to generate PINs and guess only a few times before discovering it. Randomly generated passwords are related to randomly generated numbers. Computers generate pseudorandom numbers with a lazy function called Rand() or something like it that use the time that the function is called to generate a number. This is like creating an ATM PIN with your birthday. It can be guessed if you know enough of the other pseudorandom numbers the system generated. Even perfect security - like one time pads - rely on truly randomly generated passcodes. If the code isn't randomly generated, nothing is secure. | 3 |
iwgfak | Biology | What about caffeine makes it so safe? It’s just like any other drug but you don’t risk overdosing like alcohol. Also little things like mixing drugs with cold medicine is supposedly dangerous except coffee is fine. | As others here have noted, caffeine requires just a little bit of drug to work, vs. a lot to kill you. Caffeine will perk you up at 50-100 mg (the typical amount in a cup of tea or coffee) but won't kill you until 10 grams, so the ratio of lethal/effective (aka the "therapeutic index") is 100-200, i.e. "you'd need 100 times a regular dose to kill you." For alcohol, that number is probably under 30. Alcohol also doesn't have to kill you directly by shutting down brain function; at lower concentrations, it can cause nausea but also impair your ability to protect your airway, leading to vomit inhalation which is plenty deadly on its own. Then there's impaired driving which can get lethal after just a few drinks. I think OP is also hinting at why caffeine doesn't seem to have some of the same risks in combination with other drugs. This comes down to what drugs actually do. Alcohol and other sedating drugs can have combined effects stronger than either drug alone, impairing consciousness and breathing. Sometimes they work in complementary ways that basically multiply their effect instead of simply adding up. Alcohol and benzodiazepines like Xanax or Valium are a good example; they work on the same target in different ways. Two drinks of alcohol have twice the effect of one drink, but one drink of alcohol plus one dose of a benzodiazepine can be much more than twice as strong (there's not really math for this, it's unpredictable in a dangerous way.) Caffeine tends to have more stimulating effects so mixing it with alcohol won't have combined sedation. That said, reducing the sedation of alcohol by adding caffeine may make it easier to drink unsafe amounts or do unwise things while drunk and energized, so it's not risk-free. | 3 |
kwhdh7 | Technology | How do cameras work? How did someone figure out that you could capture an image on film? | Before we had plates to capture the image and keep it, there was something called a camera obscura, basically just a dark room or tent with a tiny hole. If done correctly, light shines through the hole and creates an image on the wall. The camera as we know it is kinda a shrunken version of this "The History of Camera Obscura and How It Was Used to Create Art" URL_0 | 2 |
ewvohw | Culture | How are new words added to sign language? 20 years ago, words like Google didn't exist. How are new words added to sign language and how does everyone who uses sign language get told of the new words/signs? | I only have a couple semesters of ASL and it was years ago, but I remember it didn't take long for the more adept students in class to start making up signs either based on fingerspelling or some easily recognizable associated gesture. | 3 |
61lft3 | Physics | Why does Vanta Black make objects appear 2 dimensional? I'm seeing pictures of things painted in Vanta Black paint and they appear almost planar. How is that happening? Is the darkness of the paint making objects appear like perfect black bodies? | Our perception of depth, especially in pictures where we don't have parallax from our two eyes, is based on subtle lighting and color cues. With a lack of light being emitted or reflected, how else would you see depth? | 2 |
ba96h1 | Biology | What is the mechanism behind how we gargle water and why does it help a sore throat? | Water follows salt, and this includes the water in whatever germs caused the sore throat. Pulling out water kills the germs, and salt is good for humans as an electrolyte. Also, even the simple agitation from the action of gargling helps to dislodge mucus and other gunk to get it down or out. Edit: I know you didn't specify saltwater, but even plain water helps. | 1 |
ax8t15 | Biology | Is thimerosal safe? Anti-vaxxer relative sent me a link to this article: [ URL_0 ]( URL_0 ). Not questioning the safety of vaccines but I'm genuinely curious if thimerosal is harmful in vaccines or not? | Ah, these fools again. This study was written by [Geier son and father duo]( URL_0 ), who have had their medical licenses revoked for "falsely claiming to be a geneticist, misdiagnosed patients, diagnosed patients without sufficient tests, and recommended risky treatments without fully explaining the risks to the parents." This is in part due to an unfounded and false cure he advertised for autism whose side effects were chemical castration. The original 2003 work this paper is based on was heavily criticized and this is largely a rehash of that. Most of the authors of the paper above are working for the "Institute of Chronic Illness," an organization Geier founded. Note that this "paper" linked does not actually present any evidence of thimerosal causing autism. It simply attacks various studies showing thimersoal does not cause autism. | 5 |
j2t0bm | Other | why is it that Eazy- e and Magic Johnson both contracted HIV around the same time yet Easy-e died 25 years ago but Magic Johnson is still alive and well? | Magic Johnson was a professional athlete, at the peak of condition, and still maintains great condition in his older years. Eazy-E was ... not. Eazy-E was also diagnosed only one month before his death. His illness was likely much, much farther along than when Magic's was first detected. | 1 |
9vmyqn | Other | Why does the US vote seems like a mess and badly organized for a European - why don‘t you just count votes? | Because an election has like 40 different separate elections in it. Every body in the country only has one of the 40 elections in common , the vote for President. Next comes the vote for US senators and state governor and other state officials , of which only the people in the same state as you have in common with you. There are 50 states in the US. Next come the senator for your state legislature, of which only people in your same district have the same election. Then comes the county wide officials to be elected. No other people in the US have on their ballot except for people who live in the same county as you. There are 3142 counties in the US. Next come the city specific elections and ballot initiatives and bond financing proposals. There are thousands of cities and towns in the US. So I just roll my eyes when some non-American says "we have paper ballots and just weigh the 'yes' pile and 'no' pile separately in my small country and why can't the US do the same??" That only really works when every voter votes on the same set of issues. | 16 |
irsmb4 | Biology | How is race a social construct? I know this question sounds incredibly ignorant but i have been trying to understand for some time. My main reason for asking is because if we have dna testing that can show someone’s ancestry is this much % Italian and this much % Korean, how is that a social construct if it’s in our dna? Please understand I’m not saying race isn’t a social construct, I am just trying to understand how it is a social construct. | It’s not, unless you’re also going to tell me that a dogs breed is a social construct. Honestly you have to be some other worldly type of stupid to even begin calling it that | 25 |
63rkqa | Other | Why are pencils hexagons? | The reason why pencils are hexagonal is because the hexagonal packing like a honeycomb is the most efficient way to pack similarly sized shapes in 2-d space. See: [Honeycomb Conjecture]( URL_0 ) This means that for a given perimeter of the wood surface, making the pencils hexagonal will result in the most efficient use of the wood. | 5 |
8x2tjs | Biology | Why is it that we cry when we're both happy and sad? The same reaction for two different emotions. | I’m definitely no expert, but I think we cry when we have an overwhelming amount of emotions. That’s why some people will cry when they get extremely angry. It’s just our body’s way of releasing that emotion in a healthy way. | 3 |
6wuhje | Biology | why is it that when we get really hungry/haven't eaten in a while food no longer seems apetizing? | After you've run through the carbs in your bloodstream you revert to 'starvation mode' when your body begins to convert fat into usable energy. In order to make this manageable your brain shuts down the digestive tract and you are no longer 'hungry'. Right after you run out of carbs you get very, very hungry. A few hours later you aren't hungry anymore because your brain has shut down that part of the body. You will remain not hungry until you eat food (and subsequently run out of blood-stream carbs again) or you run out of fat, in which case you'll get so desperate you'll literally eat babies. A low-carb diet aims to keep you in fat-burning not-hungry mode until you reach your desired weight, at which point you stop dieting and/or start eating babies. | 3 |
js3cc0 | Other | - WTF is the purpose of a giant round hay bale? | They're made of hay and they're just a means of storing it. Hay is essentially dried grass stems. Bundling it up into bales makes it much easier to transport and prevents it getting blown away in the wind (compared to just leaving it on the ground). And there's no real harm to leaving them in the field for a while either, so if you don't have enough storage space in your barn, why not? When you need it, you pick it up on a tractor or forklift or something, take it to your barn and cut bits out of it to distribute to the animals. Also for the record, if a hay bale has been sitting in a field for a decade it means the farmer has died and no one noticed. The field is going to grow a new crop by the same time next year, so the bale needs to be moved before then. | 4 |
enehqq | Engineering | Why do electric cars not need gears, while combustion engine cars do? | Because combustion engine cannot turn at 1RPM or 15,000RPM, which you need to drive at 1kph and 200kph. If you don't got gears then you have to do a burn-out at every green light and then be limited to maybe 80kph driving at red line. | 2 |
8vomp8 | Other | Why does using a tootbrush how we do not make us sick? It is never sanitised and sit in your bathroom all day. Sorry about the terrible title I posted right before I went to sleep after I brushed my teeth. | Not to mention every time you flush with the lid up the flushing motion causes tons of tiny poo particles to be thrown in the air which settles on anything nearby, such as a tooth brush. The immune system is fighting off infection 24/7. Not just when you contract a disease. Plus the bristles are plastic, designed to resist contamination. And you generally rinse it off before and after each use. But still is why you need a new one every couple months. | 11 |
8s5trz | Chemistry | Why does rubbing alcohol evaporates so quickly and are the fumes heavier or lighter than air? I prefer to use rubbing alcohol to clean in places where deep cleaning isn't possible (work on my desk, etc., gym, other such areas). I've always wondered what about alcohol makes it evaporates so quickly, and where the fumes go--do they just mix in at the same weight as the rest of the air, or do they float to the ceiling or sink to the floor? Etc. Thanks | In order to turn into a gas the molecules held together inside a liquid have to break free to get into the air. This is done by adding energy to the liquid. Heat for instance. The temp needed for rubbing alcohol to evaporate - or boil - is much lower than water, for instance. And the fumes of rubbing alcohol are about twice as dense as air. So they would sink to the floor, but generally mix easily with other gases. | 2 |
8qhfft | Other | How do most Americans seemingly always know what compass direction they are facing? | I'm British and work outdoors all over my local county, and I almost always know which way I'm facing based off reference points and area knowledge. It also doesn't take long to figure out using the sun as a reference point. I'm pretty into orienteering/navigation though. | 9 |
b1sqku | Biology | why aren't there any small sea mammals? Following [this comment]( URL_0 ), I was wondering why sea mammals are typically large. Is there a biological reason why there aren't any small, let's say rodent-sized, sea mammals? | According to scientists it's most likely because the oceans and seas are too cold for warm blood animals to survive unless they were large enough to withstand it. | 3 |
7lbalq | Biology | What would happen to you if you if every part of your body except your head was submerged. Would you die? Would your skin melt off? | You would start having a pretty bad time after a few days. While the human body can survive being mostly submerged for extended periods eventually our skin starts to break down and that is 100% not good. We're land creatures not sea creatures. | 3 |
amvac8 | Biology | Does sleep debt exist? | You can definitely become more tired and exhausted without sleep, and it seems roughly proportional to how much sleep you need to "recover", but only to a point. If you miss some sleep, your normal amount might be enough. But it isnt an hour-for hour tradeoff and there are diminishing returns to how long your recovery sleep is. | 1 |
k0uv1j | Chemistry | Why does washing and drying clothes with high heat make then shrink? I thought heat made things expand | The fibers of polymer used to make clothes are stretched outward when they are made and are naturally short. Heat releases this tension and causes it to start shrinking down to its regular size. This is why you are warned to not use too much heat when you wash your clothes. | 1 |
ljivgn | Earth Science | Why does heat make the air wiggly? | You know how when you're standing next to a pool looking at the tiles on the floor, it looks all wavy? The same thing happens when you're under water in the pool and look up at the surface. The light is all wiggly, because the surface of the water is wavy. That happens because rays of light get "bent" when they go from one material (e.g. air) into another (e.g. water). Light usually gets bent most when it goes between materials that have very different densities -- water and glass are much heavier than air, so the effect is big. But glass and water are both similarly heavy, so the effect is not so big, which is why shards of glass can sometimes be almost invisible under water. Well, you know that hot air rises, and cold air falls, right? Well, that happens because air expands when it heats up, which makes warmer lighter (i.e. less dense) than colder air. So you see the cooler air is a denser material (like water in the pool) and the hotter air is lighter material (like the normal air above the pool), and the surface between the hot air and the cool air is wavy and bends the light, which makes the air look wiggly. | 6 |
8ic2rt | Physics | How does a hose work with an attachment? How does it not explode off? Does the water pressure stop? | Because the attachment is either crimped or clamped onto the hose in such a way that it can withstand the pressure of the water. | 3 |
bq2hp1 | Technology | How did old hand-drawn animation achieve such consistent color? Mainly wondering how they avoided discoloration or the presence of brushstrokes. Thanks! | If I'm not mistaken, Adam Savage (Mythbusters, [ URL_1 ]( URL_0 ), former ILM) has discussed this before and recalled the days where he would have to paint the different layers on the cell and work out what colour it would be based on where it is on the stack. The further down, the more the colour changed, so they'd need to know how many layers the image was and then adjust each layer to colour correct for it. | 12 |
99m152 | Other | How does water resistant sun cream not come off in water and does it come off as you sweat? There are a few past posts asking how sun cream protects you from the sun, but I am yet to see anything explaining how water resistant varieties do not come off in water. I'm also not sure how any suncream can last more than a few minutes since sweat will form underneath the layer of sun cream and run off your body. | > There are a few past posts asking how sun cream protects you from the sun, but I am yet to see anything explaining how water resistant varieties do not come off in water. Part of it is that it's oil based and cannot easily be washed off by water. Part of it is that some of the organic substances in the sunscreen are absorbed into the skin after some time. > I'm also not sure how any suncream can last more than a few minutes since sweat will form underneath the layer of sun cream and run off your body. Um... no. The sunscreen does not form an unbroken layer over your body that the sweat will "form underneath". The sweat comes out of pores in your skin and then run off *over* then sunscreen which covers the skin between the pores. | 2 |
k88aeh | Other | Why do blacksmiths strike the anvil before striking the metal they wish to shape? | Reference swing of the hammer? Like swinging a bat while warming up, maybe. | 3 |
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 think it does not "hurt" in general, while this might be anecdotal, it is not the word I'd pick. Depending on the brightness of each tone for green and red you might have a bad contrast and that lacking contrast makes it tireing or stressfull to read. But I doubt this is inherent to "green on red" or "red on green", i.e. you can read a dark red on a light green quite well, same goes for the other way around. But brighter green on brigher red or dark green on darker red has bad contrast (and probably similar grey values/brightness and as such is hard to read). | 4 |
a7lyox | Technology | why do some letters like "a" or "g" look different on a computer than when normally written? | Depends on the font. For example: 𝒂 𝒈 versus 𝗮 𝗴 And, in actually writing, you'll find both of the above used variously over history. But humans trend toward the simple and easy, which the ~~former~~ one of those is, so most people write like it like that today. | 7 |
9r4lzb | Biology | If the body’s nervous system works off of electricity, what part of the body is responsible for generating it? In other words, how do we get from cheeseburgers to electricity for the CNS to use? | In order to understand the answer you must first understand that the electricity in the body is actually a side effect of the real reason. Nerves do not fire electrical impulses directly, neurons actually release chemicals usually in the form of ions; those ions are electrically charged thus create a potential difference also known as voltage. That is the reason we can block pain, we just block the receptors or prevent neurons from releasing those chemicals. If the neurons used only electricity that would be almost impossible. This link might be useful for you. URL_0 | 2 |
bnrfv4 | Other | Why do people write see ID on the back of their cards? | Before chip software, you would sign the back so that, hopefully, the cashier would check the card signature vs the signature provided on the receipt. By putting SEE ID, the cashier will, again hopefully, not only confirm the signature from the License, but also the identity via the name and picture. | 4 |
ig1idt | Biology | Why are there no fruit flies at grocery stores? If I leave fruit out at my house, they quickly show up! | Fruit flies are attracted to decomposing fruit parts and ripe fruits. Grocery stores should be clean, with juices wiped regularly, thus reducing the decomposing bits. And noone wants to buy fruit that is overripe so stores make sure to only stock fruit before peak ripening. Also turnover. Fruitflies have to lay eggs in successive generations in order to be notably numerous. Produce shelves have high turnover. Your counter at home does not. | 2 |
a4lw0z | Other | Why do crossing signs now display the symbol walking and the stop hand, unlike in the 1990s, when it just said walk and don’t walk? | There has been a trend for quite some time (decades) to internationalize safety symbols, to substitute pictographs for words in almost any area with safety as the purpose. This example is just one of many. It is really just a recognition of the international mobility of products and people. Not everyone can read, and not everyone can read that particular language, so road signs, along with chemical hazard identification, labels for power distribution systems, and on and on, have all been standardized so the symbol is the same for anyone, everywhere. The conversion is more complete in some areas compared to others, but it is happening. It is a safety thing. | 29 |
627k55 | Biology | What is muscle memory? Is this just the development of neuronal pathways in the motor cortex to do a specific task? | Muscle memory is the consolidation of a specific motor task into memory, usually through repetition. This allows the specific motor task to be easily repeated without conscious effort. | 1 |
b2afus | Other | How did we discover other solar systems and such? I have really never undestood this and it really fascinates me. | Two methods. Firstly, looking for stars dimming very slightly, periodically, as a planet orbits in front of it. Secondly, measuring the very slight wobble of a star as the planets' gravity pulls at it. | 1 |
ad5x2a | Economics | where all the production companies for movies come from So I just turned on "the sisters brothers", and the first 2 minutes are filled up with logos of various production lines. One screen reads as following: "Wallimage casa kafka pictures - belfius - atresmedia cine moviestar+ ocs france televisions with the participation of canal + mobra films les films du fleuve co-production top drawer entertainment apache films knm michael de luca productions france 2 cinema france 3 cinema (??) ugc, a why not productions page 114 in association with page 114 and why not productions annapurna pictures presents...." It seems to me that for every single movie I see, there are 2-3 or several more subdivisions of production companies. Why? | Some of the entities listed in your example are not actually production companies, they're financing entities. For example, Wallimage is an agency of the government of Wallonia, Belgium, whose investments are quasi-subsidies. Belfius is a bank, which may have provided gap finance (ie. a loan) to the producers, or actually invested in the film. Casa Kafka is a Belgian "tax shelter" finance provider. France 2, France 3 and Canal + are broadcasters (ie. TV stations), they will have provided finance in the form of pre-sales. Apache Films in Spain and Mobra Films in Romania are probably involved due to the production filming in these countries, usually a formal co-production is needed to access the local tax credits even if these companies probably acted more like a service producer (ie. a company which hosts a foreign film shoot in their country). It's a great example of how difficult it is to finance a European film on this scale and how many entities will have put in a small(-ish) chunk of money to make it all happen. | 2 |
aaxkmq | Culture | Why is noon 12 “PM” instead of “AM” when it followed 9, 10 & 11 AM? | Think of 12 as more of a “0” than 12. Midnight is a new day, not the end of the previous day, and in military time 12:01 is 0001. | 4 |
8q0mcv | Other | Why do guitars have 6 strings? Wouldn't it be better if they had 5 because we have 5 fingers? | You don't pick strings based on the number of fingers you have, you base it on the range of notes you want to be able to play. 6 strings because that's the range was sufficient for composers at the time of creation. These days you can even have 12 string guitars. | 4 |
hgtvsk | Technology | why do games take so long to load in files that have already been loaded in Like, in a parkour style game like mirror's edge for example, if you fall down, you have to restart, which takes super long. But if you were already standing on the roof that you respawn on and everything was loaded in around you, why does it still take so long? I know I might have described my question badly but I did'nt know how else to word it | Usually due to lazy programming, games will often just dump the contents of the level and start loading it over again from scratch. This is easier and faster than writing the logic to clear out the pieces of the level that are unnecessary while retaining those that are. | 2 |
5sirls | Physics | how do we know the laws of physics are constant through out the observable universe? As in, how do we know that the laws of physics in our galaxy are the same as our neighbouring galaxies or even those on the otherside of the universe? Thanks | We essentially don't - we just guess But it's a VERY educated guess. Physicists over the years have conducted thousands and thousands of experiments that have shown that the laws of physics remain constant. In the absence of any evidence or any (provable) theory to say otherwise physics is able to proceed under the assumption that the laws of physics are constant. It's a very solid assumption, but it's still an assumption. If anybody was ever able to prove conclusively otherwise they would permanently alter the study of physics | 3 |
lo33dy | Engineering | With the amount of space debris orbitting the planet, how do satellites and space stations mitigate against impacts? | "Space debris" is a continuum. The frequency of a piece of debris is directly related to the size of that debris - small particles are significantly more likely than huge chunks of matter. Satellites and space stations are just built with enough external shielding to survive the constant onslaught of tiny particles (mm scale and below). Larger objects than that are **actively tracked**, and if something is on a collision course with a space station we have enough of an advance warning to move the station out of the way using its onboard thrusters. These happen every so often, maybe once every few years. Also, there's not actually as much space debris as you might think. Space is a big, big place. Even down in low-earth orbit, the chance of getting pummeled by space debris is only really a concern for very long-lived projects like the ISS that survive in orbit for many years. And this is the "high risk zone". Out in the far reaches of geostationary orbit (many times the altitude), space debris is a non-issue. This is where most satellites live, especially communications satellites. | 2 |
9y5o4m | Biology | Why do "gross" things induce gagging/vomiting? | It is mostly a response to the smell. Smell is closely linked to taste. Things that smell gross are usually that way because they are full of bacteria that would make you sick, like rotting meat. When our bodies taste or even smell these things, they make us vomit so that any that we might have eaten is brought back up before it can make us sick. | 2 |
kc4lgv | Biology | why do you feel cold when you are having a fever? What is the biological benefit to it? | In order to initiate a fever, your brain actually turns up your body's thermostat- setting the target body temperature higher than normal. This is interpreted by your body as hypothermia- after all, your normal temperature of ~98F is now a couple degrees colder than the new target of, say, 101F. As a normal response, you feel cold and your body responds accordingly by constricting blood vessels and initiating shivering to generate body heat and reach the new setpoint temperature. | 1 |
6csvnk | Culture | why do people say they will treat bombs as a terrorist attack until proven otherwise? Isn't a bombing in nature an act of terrorism regardless of who did it? | No you got it wrong. People say they will treat EXPLOSIONS as terrorist attacks until proven otherwise. Explosions could happen because of a lot of different reasons. | 24 |
6ffvtd | Culture | Why exactly movies are released on BR/DVD waaay after the release? We live in digitized world, why aren't movies digitally available right after the release? AFAIK there's no other industry so withheld by one entity (movie theater). It's like games would not be available AFTER you can play them in arcades for couple of months first. I apologize if my question is confusing, English is my second language. | It is an agreement so that the movie studios can make more money. By having a tiered release it allows the studios (and industries) to make more money off the release of a movie. If a movie was released in theaters, on BR/DVD, on HBO/Showtime, and on Netflix all at once, most everyone would just watch it on the easiest format available to them. Mostly it would be renting the movie and others would use a streaming service. By releasing the movie in theaters first, all the people willing an able will pay a lot to see it in theaters. Later the BR/DVD is sold and people who can buy it. Lastly the movie is made available on streaming services. Doing this you even get some people to do all three: see it in theaters, buy the disc, and pay for a streaming service that has the movie. | 4 |
ce5n0u | Biology | In recipes, why don’t we bake cakes and other baked goods to certain temperature, like we do with meat? For example, if I’m cooking brownies isn’t there a standard temperature at which they are done? And wouldn’t that make it easier to not over or undercook them? | Most recipes don't have temperature for donesness, however recipes do exist that say cook to a certain temperature. It's been a while since I've seen them but if I recall correctly it is usually 185 - 215 degrees F. | 2 |
dzyqsu | Physics | What is "spin" regarding subatomic particles? | Spin is an intrinsic property related to angular momentum (linear momentum is a quantity describing some mass in motion. Angular momentum describes some mass that is rotating). As far as it is intrinsic, this means it is something the particles have within them, even under no external influence (like mass or density of an object are). Although the direction of its spin can be changed, an elementary particle cannot be made to spin faster or slower; spin isn't a rotational speed. The spin a particle has determines what kind of particle it is; Those particles with half-integer spins, such as 1/2, 3/2, 5/2, are known as [fermions]( URL_1 ), while those particles with integer spins, such as 0, 1, 2, are known as [bosons]( URL_0 ). | 1 |
8li6ew | Biology | In bright light, why is it easier to shut off one eye and have the other wide open? It's almost impossible to have them both wide open, but just one seems fine. | I'm not sure. Used to work in visual neuroscience, and this is my best guess. I'd love if someone has a definite answer though! I think the main culprit is visual glare. Light travels in straight lines, but you get glare when light is scattered in a disorganised pattern \(usually strong light, like car headlights in rain\). Your brain has to process everything you see, and its less work if you can see everything clearly. If you have to perceive an indistinct shape, your higher visual processing areas have to work harder. Glare from bright light will make it harder to perceive things around you. So what I think might be going on is that glare \(which again is disorganised, scattered light\) means that you're perceiving a different pattern of scattered light from each eye. Your brain has to interpret and combine both images, which is a lot of work \(this is normally easy because they're usually the same\). Shutting off one eye \(half the signal\) means you have less work to do, and might make it easier to see. Either that or its something really simple that I've missed, like shutting one eye makes it easier to decrease the pupil size in your open eye! | 4 |
hjjrrl | Physics | Will a mirror reflect UVC light if I make a box lined with it? Can it be an acrylic mirror instead of glass? If not what material for best reflection? I am building a disinfection container. Pls and thanks. | Glass blocks UVC, and most mirrors have glass before the reflective layer, so I think it’s not going to reflect it much So I would use aluminum foil to line the sides of the container instead | 2 |
hohfwo | Other | Why does extremely bad news such as the death of a loved one sometimes not hurt that much immediately but takes awhile to “sink in”? | I saw an article the other day that said that the brain categorizes death as something 'unrelated to us.' So that means when you a death has a personal effect on you the brain basically shuts off. This mostly applies to your own death, but when your brain process the news of someone close to you, death becomes more real and shuts itself off. It takes a while for it to fully process the news and accept it as reality [ URL_0 ]( URL_0 ) | 18 |
96x3k3 | Biology | How come, in the last few decade, people begin to be more and more depressed ? | I also think that despite the constant influx of other people's lives we get from social media, we are more isolated now than ever before. You used to live in the same area as you grew up in, which was the same area your parents grew up in and their parents before them. You lived in the literal village that raised you, with the community around you to help in any situation. Now, people live so far away from their families and friends, so they're left to deal with life's little earthquakes on their own. | 21 |
awsy01 | Biology | What is Crohn's Disease? | It's a chronic (ie it lasts a long time) inflammatory disorder of the digestive system. It's not an autoimmune disorder (the body isn't triggering its own immune system) but it may be caused by a compromised immune system. Symptoms are loose stools, fever, and tenesmus (a feeling of incomplete defecation) | 1 |
8a1d9p | Biology | Why is it that when you think of eating something sour or really sweet, you feel as though you’re tasting it despite nothing being in your mouth? | man i wish i had that super power. brownies for days, none of the calories and stomach pain | 3 |
7y6vdc | Other | Why are there so many brawls in ice hockey, and why do match officials seem to care so little? | What do you mean they 'care so little'? They assess *five minute major penalties* after the boys dance! | 20 |
c9vb76 | Other | how hot air balloons navigate with accuracy | So there’s really only two means to this and nobody has answered it quite right. First and foremost you don’t steer a balloon really, you’re at the mercy of the wind. Now wind is actually blowing at slightly different directions at different altitudes, never quite 180 degree direction change, but maybe a westerly wind will have some northern push as you raise up. This can change at a moments notice but it’s all based off weather forecast so it’s very rarely/never an out of the blue change. So knowing the winds pattern at the time of flight which they gauge with a helium balloon called a “pi ball” (math is involved with this step, can never get the equation down, hate math and not a pilot so I don’t stress it) they come up with a rough game plan of where they are and where they want to be and take off accordingly. Now once they are in the air and flying many racing balloons (smaller envelopes) and mid sized balloons have a half conical flap at the bottom of the envelope. Using turning vents they can spin the envelope and catch the wind with these flaps giving a stronger turning effect, but again that is a matter of the winds direction to start with. I’ve known some pretty talented pilots that have been able to really manipulate their flight path with this technique, but this is only realistic on smaller/mid sized balloons. Turning vents themselves are a relatively new invention to the game on racers. In the past they were really just used to manipulate show balloons (much larger) for crowd viewing pleasure. | 14 |
760r0f | Economics | How do companies determine the cost of acquiring a customer? The cost of acquiring a customer is brought up a bit in Shark Tank and I have no idea how that can be calculated. It feels like there are so many variables and such. Could I get an easy-to-follow explanation? | 1) Time and material spent on sales & advertising. If you spend $1 million on an advertising campaign and it averages 10 new customers, then that's at least $100K to acquire the customer. 2) Time & Material getting the new customer set up. This covers any kind of material that you have to give the customer (such as a device to use your service), the time it takes to create the customer's back-office information (automation is a good thing here), and any time/material it takes training the customer on the use of your service before they can start giving you money on a regular basis. | 1 |
5r8yhw | Culture | Military officers swear to protect and defend the Constitution of the United States, not the President Can the military overthrow the President if there is a direct order that may harm civilians? | The last 44th President had the lowest approval rating of the current Armed Forces enlisted and officer ranks of any in modern History. Just keep that in mind when you attempt to use the military for bashing the 45th | 54 |
6ku4m9 | Technology | How knowing mathematics is important for learning how to code a computer | As a web developer, I wouldn't say I use much mathematics, what I do use is logic. Maybe math is heavily suggested because it forces you to think logically? On a side note, I know certain programming like motion (for games) and such does deal with math. | 5 |
bcq96k | Culture | Why are white Americans not called European Americans? Similar to Asian Americans and African Americans. | Historically, “American” was used by people in power in the US to refer to white Americans Something else-American was to identify non white people. White people were the default, essentially Now, we say white Americans because we know white shouldn’t be assumed. Many people prefer black Americans instead of African Americans because that’s actually what people mean. Not all people from Africa are black Caucasian is the white equivalent of African American Does that make sense? | 4 |
bmdivu | Biology | How come there are some automated body functions that we can "override" and others that we can't? For example, we can will ourselves breathe/blink faster, or choose to hold our breath. But at the same time, we can't will a faster or slower heart rate or digestion when it might be advantageous to do so. What is the difference in the muscles involved or brain regions associated with these automated functions? | The heart and the intestines have a type of muscle called cardiac and smooth muscle respectively. These muscles are not innervated by nerves that can be voluntarily controlled by the brain. Breathing and blinking fuctions are controlled by skeletal muscles (like your arms or legs) which are innervated by nerves that can be voluntarily controlled. Extra info for the curious: blood vessels also have smooth muscle cells that control the width of your vessels to adjust your blood pressure. These are all innervated by the sympathic nerves (unvoluntary control). You have probably heard of the fight or flight response. They use the sympathic innervations to STOP your gut fonctions (because they are useless in a life or death situation) and INCREASE heart rate and blood pressure. Edit: clarification and typo Edit2: yes my bad, the heart is actually made of cardiac muscle like people are mentionning, had a brain fart last night. But the sympathic innervation remains the same. | 12 |
5rx32x | Biology | Why crying for happy situations feels so significantly different than crying for sad reasons About a month or so ago, I had a happy memory and starting bawling (I can elaborate if needed). Last night, I cried for a sad reason (long story. Can elaborate if needed), and the first thing I noticed was how different the two felt. I'm not fully sure how to describe the differences, just that there was a noticeable one. What might cause these two situations to feel so different, even though the same action is happening? The happy memory cry felt exactly like a cry for a sad scene in a series, which is another reason I'm confused. Is it a case-by-case thing? And what actually changes? | Not an expert but I gave it my best effort. Good question! Crying is triggered by a tiny section of your brain called the amygdala. It can't tell the difference between good and bad experiences, it only responds to how strong a feeling is. The amygdala will trigger crying whenever you feel overwhelmed although it's not entirely understood why. When you are over-stressed or overjoyed the amygdala will often respond with tears. The reason for the big difference in how you feel is based on the rest of your brain processing the cause of the crying. The left prefrontal cortex of your brain is more active when you feel happiness, and enough happiness can overwhelm the amygdala and cause crying. On the reverse, the right prefrontal cortex is more active when you feel sad and the amygdala gets triggered if the experience is strong enough. So you feel the emotional experience in that frontal section (called the neo cortex) and if it's stressful you feel bad and if it's good you feel better. So the signal for crying only checks just how strong the emotions are, not what kind of emotions are present. The role of crying in response to strong emotions is not fully understood but since we feel relief after a good cry it's thought that it helps the brain process the feeling of being overwhelmed and out of control in a world that's so much bigger than us. The brain is really neat and was called "A machine that a ghost can operate" by Noble Prize winning neurophysiologist Sir John Eccles. To me this is just the biological explanation of a spiritual experience. | 1 |
7ihxex | Technology | Why do freeware programs almost always try to install toolbars, bing, antiviruses, and other junkwares? | It's important to distinguish a true "freeware" program, where the author(s) and copyright owner(s) let you use the program expecting nothing in return, and what you've discovered- **adware**. Adware is a general term for programs that "pay for themselves" through intruding on, modifying, and monitoring your activity. They show ads to you, and advertisers pay the program's owners in return. Other companies may pay them to bundle their software with the program- Adobe bundling McAfee junk with Acrobat and Flash is probably the most familiar example. Still other programs take making money off you into their own hands, and these you could consider as spyware / malware! When you install a program, you are trusting the authors that the program is safe and friendly. That's not always true. These programs can spy on you, your browsing activity, and steal your information. They can redirect you to other sites. They can install more complex programs to eventually take over your computer and make it part of a botnet or ransom your data, both of which are very lucrative. In summary, these programs aren't free! You're being taken advantage of in some ways that you can see, and some ways that you can't. In fact, the cost is much higher than any use you might get out of these programs- you may lose your money, your identity, and may have to rebuild your entire computer. | 4 |
d1q4qp | Other | What’s the difference between a therapist, psychologist, and psychiatrist? | Main difference is in terms of qualifications. Psychiatrist is a medically qualified doctor who has specialised in psychiatry and can prescribe medication. A psychologist is not medically trained but has trained in psychology and can not prescribe medications but can do therapy sessions and evaluations. A therapist is usually only trained in either DBT or CBT therapies and will usually only run therapy sessions with their patients. Edit: source I work in a psychiatric hospital :) | 5 |
761xqi | Biology | Why does it take babies such a long time to learn basic motor skills compared to animals that are able to do it close within a month or even as soon as they're born? | No one else seems to have brought this up yet, so I thought I'd point out that there's a massive difference in what's considered 'basic' between humans and other animals. Walking on two legs is *hard* compared to walking on four. The kind of fine motor control you see babies learn in the two years of their life - grasping, rotating etc - is about as good as some species of primates get. Even aside from humans being born essentially premature, there's just so much more to learn about fundamental movement, and those fundamentals let us move on to incredible things. | 20 |
67s9rs | Other | Why has there been such a marked increase in spam/scam phone calls in the past few years, and is there anything that can be done about it? | I started getting regular (twice a week) calls from the same company ( i forget the name now) trying to get me to claim for an accident I hadn't had. During one of our calls I let them give me the whole sale run down rather than hanging up until they mentioned the company name. Using the company name (and the london number) I found the address of their building they were calling from on google. The rep freaked out a bit when I told them I pass thru London a couple times a year and would be super interested in checking out their building at (address I found) and would be very interested in talking about accidents as they seem so eager. I stopped getting calls from them after that. | 29 |
jhtw6h | Other | How does Sacha Baron Cohen gets so many people to sign a release. I see the scripted storyline, but all the other people? I mean geez.. | Feign that it is for a reality type show but the footage can be used in other mediums as deemed fit by the production company. | 3 |
8jaagj | Biology | During sleep, how does our body know to suddenly wake when there is a disturbance in the environment such as a loud noise? | There's another aspect of this besides subconscious training. Disclaimer: I'm not a sleep expert, but I've read a lot because of my own sleep disorders. You know how your eyes close when you go to sleep? They close so what you see can't bug you and wake you up. But you don't have ear lids, so your brain does something cool: it mostly turns off your ears. It's like your ears have little fingers way down on the inside that plug them. (They don't really, but it's like that.) You know how, when you plug your ears, you can still hear things that are loud, and you can even hear things that aren't loud if you listen hard? That happens when you sleep, too, when your ears are mostly turned off. Your brain mostly turns off your other senses, too, like your smell, taste, touch, and body position. This is really helpful when you're hurt or sick, because it keeps pain from waking you up, so you can sleep and get better. Your body gets better a lot faster when you're sleeping. You should know that if pain is bad enough to wake you up, you should go see a doctor. Another cool thing your brain does when you sleep is mostly turn off your movement. It's kind of like your brain holds your arms and legs down a little. It's weird, but it's helpful, because if you have a dream where you're running, you won't start running in bed and fall out. | 6 |
e4bf4t | Chemistry | why does 60 degree water feel freezing compared to 60 degree air? | Two reasons: 1. The water touches your skin everywhere because it gets through your clothes and 2. it conducts heat faster than air, which is a gas. The air doesn’t touch your skin where it’s covered by clothes. There’s a layer of warm air (warmed by your skin) between you and the clothes you’re wearing that insulates you. Being nude in 60 degree weather would be pretty cold, but it would still take much longer to feel as cold as 60 degree water because water conducts heat much faster than air. Liquids conduct heat faster than gases and solids conduct heat faster than liquids. (Conductivity goes solid > liquid > plasma > gas, and it’s because of the way molecules line up in those states.). This works the other way, too. You can survive for awhile in 140+ degree air (as long as it’s low enough humidity and you’re drinking enough water), but if you’re in a 140+ degree pool, you’re going to die pretty damn quickly. Like five to ten minutes to full-body deep-tissue burns... | 2 |
6ze13n | Engineering | How is renewable energy more feasible than the alternative if it relies upon rare-earth materials? Ignoring the environmental impact for a moment, how is something like wind or solar energy a more feasible long term solution for energy resources vs. coal and oil when they use rare-earth materials such as Lithium for batteries? | Rare Earth metals are poorly named. They're more inconvenient Earth metals. They don't exist in easily harvestable veins like iron or copper and there are no large deposits in Europe or North America But China has a shitload of them! Harvesting "rare" Earth metals like neodymium is very similar to harvesting aluminum. You have to chew up large quantities of land and process the rock to separate out the grains you want, then process them. Neodymium is the 28th most common element in the Earth's crust, it is about twice as common as lead and 3/5th as common as copper. It's not rare, just crappily named Lithium isn't a rare Earth metal and isn't rare either, it exists as massive lithium brine fields that need processing. We've significantly ramoed up the amount of lithium we process over the last couple decades which is why battery prices have been falling | 5 |
en0sos | Biology | Why can't we reproduce near extinct animals genetically the way the livestock animals do? | They can clone or alter existing animals because after they have done the genetic work - such as copying the genome to clone sheep, or splicing in jellyfish DNA to create glow-in-the-dark rabbits - they can implant the embryo in a live animal that is close enough to the right type - preferably identical - that it can successfully gestate the clone. We can't make Jurassic Park a real thing because we lack living dinosaurs to implant the 'cloned' egg into. | 4 |
b6wdcg | Technology | Why are records still made of vinyl? I know they're more of a collector's item nowadays, but haven't we invented any materials that are more durable or would otherwise be better for the job? My boyfriend is really into records and he's tired of me pestering him about this. I've heard that records used to be made of something called shellac and then it turned into vinyl around the 1930s. But that only caught on when they started using lighter needles that didn't damage the record. It's almost 90 years later now, haven't they made a material better suited for the job? Maybe something that's more durable so they don't scratch as easily, for example. Edit: I'm adding this because it seems to be coming up in the comments a lot: I am well aware that CDs and other digital media (mp3s, Spotify etc) exist. What I'm curious about it the reason why vinyl is being used for the big black records my hipster boyfriend likes. | Can we get one answer that does not talk about why vinyl is good? Can someone speak about a a better material without comparing it to vinyl? We know vinyl is good, but what is better? | 15 |
fzzv7e | Technology | Why is online participation with a unique keycode (and in-person follow up for those who don't respond in time) considered reliable for the US Census but not for Voting? [see link] | I am sure that your device is malware and virus free; but can you guarantee that for everyone in your street, in your voting district. Imagine the sort of attack that could be put together by a well funded, not necessarily foreign, team that wants to influence the country for the next four years. This attack on the vote will scale very easily, find a bug and exploit it. It would require the same number of people to change 1000 votes as it would to change 1 vote I will let [Tom Scott]( URL_0 ) explain better (on line voting is from about 8 mins in) | 4 |
lgmsxi | Biology | Why a horse need to be put down if it breaks a leg Why do they kill horses if they ever Break a leg? Can't they heal it instead? | It's a very long healing process for a complex limb. Horses put a lot of weight on that limb and they can't just lie down and heal for weeks at a time. Horses are also fairly nervous and quite stupid. They will not take it easy. They will not like the cast. They will not stoically handle the pain. Most of the time, horses are just one little incident away from freaking out over something. The short of it is that it's extremely hard to help a horse recover from a broken limb and it's very likely that the horse will either develop complications from a poor healing process or simply break the limb again because it doesn't know how to take it easy. With the risk of failure being so high, it's usually not worth trying unless it's an extremely valuable horse that still has a breeding purpose that doesn't rely on it having a perfectly functional limb afterward. | 5 |
6r4goy | Repost | What are birthmarks? Why do we get them? | u/lol_dubldown had this to say: > Yerr not alone in askin' etc etc > URL_2 > URL_3 > URL_0 > URL_4 > URL_1 | 2 |
fve6uf | Other | Why are some colours synonymous with emotions, and where did this trend originate from? Like how blue is seen to represent sadness, red is to represent anger, yellow is joy, and green is envy/jealousy, why is this a thing in humans, and how did it become an association (as in, what is the history)? Like I kinda get how blue is sadness, as the phrase “feeling blue” exists, but it would have to come from the colour being seen as sad? And red for anger is like when you’re angry, your face goes red maybe? I’m not too sure about other colours like yellow and green though. Also, please actually explain it like I’m a five year old; I’m pretty slow. | I think it’s a cultural thing. In the west red can mean anger and other things, and I believe in China it represents good luck. So you and I may think of blue as the color of sadness but someone from a different part of the world may think it’s the color of hope or something like that. Someone else could probably better explain the origins of these links but that’s what I think. | 1 |
msknlp | Biology | Why is it that when you're sleepy and drifting off, any movement or disturbance can be so uncomfortable or almost painful? I'm certain this isn't just me. During the day when I haven't gotten enough sleep, and I'm starting to nod off, if someone tries to get my attention or I try to move myself or really any disturbance I can sense, there's a very unsettling feeling I get, like a mini, momentary adrenaline rush, that attempts to jolt me awake. Is there a name for this? | I never thought about it but you’re right. My cat tends to jump up on me as I’ve just drifted off and then I’m wide awake for another hour at least and that feeling of sleepiness is gone. It’s miserable and you’re right it does kinda hurt to start awake like that | 1 |
d64nck | Biology | How can someone with a peanut allergy develop a semi-immunity to peanuts? I've seen this article a few times, but I'm not sure how ingesting any level of something you are allergic to won't kill you. Also, can this be applied to various other allergies? URL_0 | Immunotherapy has been applied to many allergies, yes. There's two general competing mechanisms that drive allergy. The first is what you could call the "pro atopic" side. This is the allergic response, and in these types of allergies it is mediated by a class of antibody called IgE. To simplify it a lot, more IgE against the allergen = more allergic response. The second is the regulatory side. The regulatory side is what inhibits the allergic response and reduces IgE levels. This is mediated, in part, by a class of antibody called IgG4. Also very simplified, more IgG4 against the allergen = less allergic response. We know that some factors favor an IgE response. These are: later exposure in life, intermittent exposure, high dose exposure. We know some factors favor an IgG4 response / lower IgE response: earlier exposure in life, consistent exposure, low dose exposure. Immunotherapy works by giving you a low dose, consistent exposure to the allergen to build up a regulatory response. It's been proven to work in a lot of clinical trials for many common allergies, but work is still ongoing. Part of the trick is that you have to do the immunotherapy just right, or the allergy may just get worse. The best preventive measure, though, seems to be exposure to the allergen before 1-2-years-old (based on other trials). | 2 |
5obwem | Other | Why are most erasers pink? | Because people expect them to be pink. Faber was a company that made pencils, and erasers. They used Italian pumice in rubber to make erasers. The pumice supplier ran into a vein of pink pumice, and the Faber people loved the look of it. They named their product the Pink Pearl. When the pumice isn't pink, they add dye to keep the product pink. But you can't trademark "my product is pink" unless it's a dye or paint, so everybody can make pink erasers. Some drafting and art companies stick with white to save on dye, but for the elementary school crowd pink is the color. | 1 |
av4u27 | Biology | What keeps bed bugs in check? Why haven't they taken over the world? Do they have any natural enemies? They seem pretty unstoppable - easy breeders, can live a long time without food, can survive harsh conditions, easy hitch hikers, and they feed on an endless supply of human blood. | Tbh they probably want to avoid attracting too much attention. Becoming the enemy of humanity is a scary target on your back. | 42 |
dgd61h | Engineering | How is it possible that the Flint Water Crisis is still ongoing after 5 years?! | Because, while other cities spent the previous decade and lots of dollars to update their pipes, flint didn't. | 5 |
6l5snq | Biology | Why is getting one's tonsils removed as a child such a standard procedure yet so much more complicated as an adult? | No expertise in this area but recently got mine removed at the ripe age of 19. It's really simple from what I've been told and research. As someone grows and develops, so do their tonsils. You can think of them as a plant with roots. While someone is young, their tonsils are not yet deeply rooted. The older you get, the more deeply rooted your tonsils get. That means you have tonsil tissue closer to heavily vascular areas or even veins and arteries and more tissue to remove. Too much pressure or a wrong cut can lead to a spurt of blood in your throat which instantly starts to clot - cutting off you ability to breath. That's why aftercare and being gentle is so important in an adult tonsilectomy, even in one done while young, however there is not as much risk. It's also extremely painful, and takes much longer to heal just because of how extreme it is and how young people just heal alot faster. It took 14 days under I felt I was at 95% and another 7/12 days until my new throat felt "normal" again. | 1 |
l6ptb7 | Economics | what is a hedge-fund? I’ve been trying to follow the Wall Street bets situations, but I can’t find a simple definition of hedge funds. Help? | You should think of hedge funds in investing terms similar to the difference between a basic car like a Honda Accord versus say a Ferrari. Most regular individuals will invest in stocks or index funds, or mutual funds, just like most people will have a regular car. These will only go 'long' positions (which just means they tend to only buy stock in companies they like and hope they go up for a profit). Hedge Funds are the Ferraris of the investment world, they are private and generally only accessible to the wealthy. They can use a host of different complicated financial instruments to invest money. The most basic example is shorting, basically betting against a company. How does shorting work? Example: John shorting company A Let's say you own 1 share of company A and John believes its stock price will go down. John will borrow that share from you and promise to return it at a specified date (let's call it a month from now.) So he borrows your share, sells it on the open market for its fair price, call it $100, believing it will go down. Let's say in two weeks the price goes down to $50. John can repurchase the share for $50 dollars, give you back the share worth $50 and profit $50 off of the decline of the stock price. Bear in mind this is an extremely risky strategy, because the maximum profit to be made off shorting company A would be $100 a share (because the stock can only go down to 0), but theoretically, the price can go up to anything, $1,000, $10,000, etc. In the event company A's share price went to $1,000 by the end of the month, John would have to purchase the stock for $1,000, losing $900. Extremely risky. These sorts of more complicated financial instruments are why hedge funds are only accessible to the wealthy. The US has drafted laws that are supposedly meant to 'protect' lower income and less knowledgeable investors (apparently concluded from how rich you are) by only allowing those with a certain net worth to invest in these types of complicated strategies. This is also why they charge substantially higher fees than regular investment managers (think 2% of assets managed and 20% of profits, compared to roughly 0.5-1% for a regular actively managed investment fund). Now, being that hedge funds are the Ferraris of the investment world, they should have all of the bells and whistles that a Honda does not. Sure, both are trying to make your money go up, just like cars get you from point A to point B, but hedge funds should ensure a smoother ride and only be staffed with the best talent. In reality, this isn't necessarily the case, but that is a whole other discussion. In short: Hedge Funds are Ferraris, while regular investment funds are Hondas. Ferrari is shiny, loud, fast, and seems amazing compared to a boring Honda, that is, until you realize new tires will cost you 5 grand, you can't fit your groceries in the trunk, and it costs an arm and leg to maintain. Honda actually seems like a cheaper, better way to get around that will more easily fit your needs. Not sure how well I explained it but I've worked in industry so feel free to ask any questions, happy to help answer them more thoroughly or explain it differently so it makes sense! | 15 |
66m902 | Culture | Why are other ideologies and differing ways of life viewed as threats by some governments? Surely if there are no human rights violations going on and the people are generally happy with how things are, why is there a fear of the way others live and a desire to enforce change, especially if it's what those people want? See: communism and democracy; Christianity and islam. | they fear being replaced. it's as easy as that. if the other way of life gains power it will mean their way loses control. Obviously there usually are legitimate reasons to oppose something but at its root its the fear of a loss of power. | 2 |
hqxr3p | Other | Why is dark humour funny? Does liking dark humour make me racist, misogynistic or sexist? | Humor is a concept that is hard to define. One definition says humor is considered to be the subversion of expectations. By saying something extremely unexpected because it's not socially acceptable MAY be considered funny as long as the intent is humor and the audience takes it as such. Racism, sexism, misogyny, etc. can be considered a pattern of behavior or belief. Occasionally making racist joke doesn't make you a racist, though it can make you insensitive and if the audience doesn't find it funny then you're in trouble, but I'd hesitate to call a single instance of dark humor an indication of deeply held beliefs or biases | 4 |
8rkako | Other | Why do cars and sport games come out “a year early”? You can get a Nissan 2019 in 2018 and you can play FIFA 19 in 2018 | It’s released towards the end of the year to be enjoyed during most of The following year. | 3 |
lb6umv | Other | oh Why is Kaliningrad and the area surrounding it (a wedge between Poland and Lithuania) part of Russia? | Historically, Russia's foreign policy can be summed up in three words: Warm water ports. They want them, they need them, they will fight tooth and nail to get them. Russia fought the Ottomans multiple times to acquire territory on the Black Sea. Peter the Great went to war with arguably the strongest empire in continental Europe (Sweden) for St Petersberg. They got their asses kicked by Japan just so they could have a port on the Korean Peninsula. After WWII, the Soviet Union was granted direct control of Königsberg by the Potsdam Agreement and renamed it Kaliningrad in honor of Mikhail Kalinin. Even with the dissolution of the Soviet Union, they still kept control of Kaliningrad, because it's a warm water port. | 2 |
htghyy | Other | Why is it acceptable see to a man's chest but not a woman's chest in public? Why are a woman's nipples always covered even if you can see her breasts? | There's no good reason, it's just a cultural tradition. There are many cultures in Africa for example where both sexes are usually topless. | 1 |
9p9xq2 | Biology | How does exercising reduce blood pressure and cholesterol to counter stokes/heart attacks. I was wondering how exercising can reduce things such as blood pressure? Surely when you exercise the heart rate increases to supply blood to organs and muscles that are working overtime, meaning the chances of strokes and heart attacks are higher. So how does this work because wouldn't doctors advise against this to prevent these events from happening? Edit: 31k Views... Wow guys, thats crazy... | The ELI5 answer is your body is a sack of blood, your heart is a blood pump. The fatter you are, or the more you weigh, the more blood there is in your meat sack. The size of your blood pump really doesn't change all that much in regards to your body size, so the more blood there is in your meat sack, the harder the blood pump has to work. The blood pump can only work extra hard for so long, before it starts to breakdown. So the better thing to do is to decrease your overall weight, through diet and exercise, which also decreases the amount of blood there is in your meat sack. This allows your blood pump to work more efficiently, and it allows it to last longer. | 19 |
8workx | Economics | Why are trucking weigh stations ALWAYS closed? | I live within 15 miles of two stations and they are almost always open. They even check water craft for invasive species. I do live next the the ID/WA state line so one station is in Idaho the other in Washington. Only really see them closed on holidays. | 11 |
d09w6m | Culture | How did plastic straws specifically become targeted for eco-friendly banning, but similar disposables like plastic forks and spoons didn't? | I sort of question the premise. Compostable utensils are becoming increasingly popular at most places. Perhaps straws have the slight edge for reasons people have described in this thread, but other plastic utensils are not far behind. | 19 |
85n9sv | Technology | What's so special about AMD Ryzen CPUs? I've noticed plenty of articles online discussing the various features of this type of professors. Can anyone explain the main differences as opposed to to Intel i5 or i7? | AMD CPUs have always favored more cores, sacrificing performance per core for more cores to do work with. Contrast this with Intel, whose i5 and i7 CPUs are quad core, nothing more. However, per core, in general, Intel CPUs have much better performance. Historically, even with more cores, AMD CPUs perform worse than Intel equivalents, meaning that Intel had a pseudo-monopoly on the processor market. If you've ever taken an economics course, you know why monopolies are bad. AMD Ryzen CPUs aren't super special in the sense that they're some revolutionary technology. They are merely good enough to rival the newest Intel processors. This means that Intel now has pressure to push out better products again. People were complaining that there was very little difference between a 6th gen and 7th Gen Intel CPU. However, since AMDs Ryzen release, Intel's 8th gen CPU is once again a clear improvement on the 7th Gen. And that's why AMD Ryzen CPUs are special. They promote competition and innovation in the processor market. | 3 |
6ky2bv | Biology | How does a person's weight fluctuate around 2-5 lbs within a day, yet their body composition doesn't change at all besides adding a few ounces, and losing a few due to food and waste? | Hydration status is likely the main reason. Water is heavy and nobody usually takes in the exact same amount every day. Sodium intake can make you retain a little more water instead of peeing it out. | 2 |
8ajvfz | Other | News agencies generally follow a standard to not report news of suicides due to copycats. Why hasn't a similar standard been established for reporting gun shootings? | Experts warn against reporting both suicides and homicides for similar reasons. Why do news agencies heed one warning and not the other? Simple answer is that homicides get much higher ratings than suicides. News is big business. Honestly I think many major news outlets do a pretty incredible job considering their profit-motivations. It's far, far less than ideal, but it could be *so much worse* | 9 |
6i68zc | Other | Why won't the characters from marvels Netflix shows appear in Infinity War? | Because production realities make it impractical for the TV characters or events to appear in the movies while it is possible for the movie characters and events to appear in the TV shows. To keep everything consistent stories and events would need to be approved by one person or group - but the TV shows are written and produced in much greater volume (essentially a 15 hour movie every year) and on a much shorter schedule (moving from writing to filming in weeks or days). So Kevin Feige or his team would essentially have to work on a daily basis with every single show, in addition to the movies, and keep it all straight. And then there are the production issues. The films are written and then filmed months in advance (I'd say the scripts are done at least 18 months before they reach the theatre). By comparison TV works only a few weeks ahead. This means that it is easy for TV scripts to include details from the movies because those have already been shot and are in final post post-production by the time the TV episode is being written. But for a movie to tie in with a TV show you need to be predicting where that show will be almost 2 seasons in advance. While a show might have a long term plan about events there is no way to ensure it will stick with it - not only might the show be canceled but any number of real world things could happen that force the writers to write a new story line that may not match up with the movie that was already filmed for millions of dollars. And that's assuming the show doesn't get canceled or there is a writers strike. Actors are a big issue - you can't guarantee that an actor will still be there (arrested, died, didn't renew their contract, poison for the ratings so execs demanded they be written out) so having them appear in a connected movie that won't hit theatres for another season is a huge risk. | 1 |
bayhad | Technology | How is video and music data stored digitally when there isnt any power in the device (battery dies)? | When you toggle a light switch at home and the power goes out, it remains toggled in that direction until/when the power is restored. The 0/1 toggle stays where ya put it. | 3 |
meazfx | Physics | How can nothing be faster than light when speed is only relative? You always hear this phrase if you watch something about astrophysics 'Nothing can move faster than light'. But speed is only relative. How can this be true if speed can only be experienced/measured relative to something else? | Wow, OP. You've asked the very same question that Einstein asked himself to come up with one of the most revolutionary ideas in physics! You are correct that speed is relative. If I'm walking up an escalator at 2 m/s and the escalator is moving at 5m/s then my speed relative to a person standing still at the bottom of the escalator is 7 m/s, but to someone else on the escalator who is standing still and waiting patiently for the escalator to transport them to the next floor my speed is 2 m/s. But light travels at the same speed from all perspectives. Say a spaceship is traveling at 90% the speed of light. If I shine a torch from the back of the spaceship to the front and someone on the ground can see through the spaceship's window, then the light from the torch will appear to move at the speed of light to both of us. But the escalator example would suggest that to the person on the ground, it should be traveling at 90% of the speed of light + the speed of light i.e. at 190% of the speed of light. So how can it appear to move at the speed of light to both of us? Well, if the person on the ground is looking through the window and everything in the ship (including not only the beam of light from the torch, but the people inside the ship) is moving in slow motion, then the beam of light can appear to move at the speed of light. Mind blowing, eh? To solve the paradox, time must be relative! Time inside the ship appears to be slowed down to the person on the ground, and conversely everyone outside the ship looks like they're running around like ants to the people inside. Actually, there's a bit more to it than that, since distances are affected too. But thinking about it like this is a good starting point. | 23 |