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60480q | Other | How did "X" come to mean things like "close", "no" and "cancel"? | This was easy to google: An x mark (also known as a cross, x, ex, exmark or into mark1) is a mark (x, ×, X, ✕, ☓, ✖, ✗, ✘, etc.) used to indicate the concept of negation (for example "no, this has not been verified" or "no, I don't agree") as well as affirmation (for example in election ballot papers or in x marks the spot). It is often used opposite the check mark or tick (or the O mark used in Japan, Korea and Taiwan). The UI history point of view (based on semiotics as well) dates it to Atari TOS 1.0, and later it resurfaced in Windows 95: [x] is a true icon, not representing a letter but representing an action, and only adopted to represent ‘close’ well after the development of graphics-oriented operating systems. The first appearance of [x] in GUI design was likely the Atari TOS, possibly influenced by the Japanese batsu and maru conventions. Thanks to a last minute design change in Windows 95, and the mass adoption of Windows worldwide, [x] has become the standard symbol for ‘close’, a symbol that dominates web, app and software design today. I've also heard the version of x representing crossed arms as in "defense" or "don't want", but really couldn't find anything to support this claim, so take it with a pinch of salt, just mentioning because always found this curious and maybe someone can shed a light on this EDIT: re-reading the link I posted, the "crossed arms" is elliptically mentioned in the article. The concept of batsu is actually 2 arms crossed: Batsu. In Japanese culture, the batsu (literally: ×-mark) is a gesture made by crossing one's arms in the shape of an "X" in front of them in order to indicate that something is "wrong" or "no good". | 3 |
6g1v68 | Physics | Who was the first person to think that atoms existed and make up all matter? How/why did they get the idea? | Most fascinating thing is that first atomic theories were developed back in ancient Greece. Idk how, but some of them got it quite close to the truth, actually. | 3 |
75ewnh | Other | Why are unskipable advertisements allowed to be on official Blu-ray and DVD releases of movies and TV shows before the menu loads | Because there's no laws saying they can't do it, and no court decisions that make an argument against it. | 3 |
gtezr3 | Mathematics | From a cryptography POV, why were the Navajo code talkers so difficult to decipher? I had always just believed it was because they were isolated, but I'd been thinking about it lately and that just doesn't hold up. Can someone familiar with code breaking and encryption help me understand why they were nearly impossible to understand, while almost every other cipher was eventually cracked? Thank you! | One thing to keep in mind is that they were mostly used tactically, where the value of deciphering drops by the hour Hence the ease with which a natural speaker can transmit a message (without relying on machines or tables) made them very valuable. | 10 |
b7diz3 | Technology | How do open world games go without interstitial loading screens? So if you’re playing a typical non-open world game, every time you lose a life or enter a new area, you have to sit through a couple minutes of loading screens. How do open world games circumvent this, to create a seamless experience as you transition from one area to the next? Is an open world game continually “streaming” data off the disc/hard drive/cartridge and dumping unneeded assets from RAM on the fly? | Yes, that's exactly what it is doing. The open world is split in to sections, and only the section the player is close to is loaded. You notice if you die in open world games it will take a bit of time to load the area you respawn in. | 1 |
b0d6vm | Engineering | Why are some boats pointy on both ends, while other boats are pointy in the front and flat in the back? | A tapered stern allows the water to gently come back together to fill the hole the boat made as it passed. [The front and rear of the hull stay wet at the waterline]( URL_1 ) Square sterns are more efficient on faster craft, where the water cannot flow back together fast enough. The faster shape is squared off, [so the water can detach from the back of the boat and not drag on it.]( URL_0 ) | 3 |
ez7ngn | Engineering | Why planes won't crash because of turbulence? | Turbulences are to planes what ocean waves are to ships. They actually can damage the vehicle, yet like at water and ships we can estimate the strongest turbulences possible and design the aircraft to withstand them. Also even if a major turbulence hits a plane, the plane itslef just shoots through it due to its high mass and velocity. Also if the plane doesn't break in half, it just tumbles and falls until it has enough forward speed to generate sufficient lift again. Edit: Typo | 4 |
6t1tgc | Other | Why often in court do lawyers say "my client" rather than something like "Mr/Ms"? | Lawyers see a lot of cases. It's very embarrassing to accidentally say the wrong name due to a mental mix-up. This prevents such a mistake. | 1 |
gt32wv | Technology | How does encryption really work? What prevents hackers from just stealing the key and stuff? | The math behind this is quite complicated, so maybe someone else can fill that in, but I'll try to at least give an example. Most encryption on the internet is called "public key" encryption. If you want to send me something secret, such as a credit card number, you first ask for my "public key," which I can give to you, or even just have posted on my website. It's no problem that anyone can see it. When you use my public key to encrypt the data, it now becomes unreadable even to you. Even though you have the data and the key, it was a "one-way" operation, and the only way to get the data out again is the "private key," which I have kept safe on my personal computer. If we wanted to communicate back and forth, we would both create encryption keys, and then trade just our public keys. Now you can send me a message that I can read, and I can send a message that you can read. Other people who know these keys can *send* us whatever messages they want, but they can't open it without knowing the private key. One catch to this. Say someone was able to intercept our communications from the very beginning. When they saw that I was sending my public key to you, they jumped in and swapped it with their own public key. Now when you send a message to me, they jump in, decrypt it with their private key, read it, and then re-encrypt it with *my* public key, and pass it along to me. They were able to read the message without me ever knowing. One way to counter this, is to create places where anyone can post their public key in a very open, widely available fashion. That way, you can always check whether the key that you think is mine matches what is listed in one of these registries. When you go to a site that warns you "this is not secure," that's one of the possible reasons for this error: the information being given to you by the website does not match what's posted on a registry. 99% of the time, it's because someone screwed up their configuration of the website, but in a rare case, it could be that something is trying to "snoop" communications to that site. | 3 |
e7brov | Economics | How do employers or corporations benefit from unions? | They don’t directly. Long term gains from employee retention and morale aren’t usually accounted for in a lot of western cultures. If you look to countries like Sweden the gains are obvious, less time loss to pseudo illness, higher output per man hour etc. Unions are only still strongly active in countries or sectors where there’s additional financial slop in the system. Not sure about the US’s labour environment but other countries I’ve lived in have strong construction and essential services unions. Overall corporate bodies do benefit due to the above reasons, but the current climate of CEO driven corporate commercialism means waiting for 5-10 years doesn’t benefit board/stock holder/CEO. | 5 |
5p4xe6 | Biology | Why do humans sleep and why does the stuff that happens during sleep not happen when awake? I don't get sleep, in my head it seems like it achieves nothing. You don't actually gain energy (since energy comes from food) and I don't get why you couldn't just grow, as for memory that happens during sleep, while you are awake. We could be so damn productive without it. | Sleep is about shutting down and then using that time to repair your body and reorganize the stuff in your head. Imagine you're a librarian and you have to organize a bunch of books back onto the shelf. If you had a hundred people constantly taking out books and delivering new books which pile up on your desk. Your job is really hard. Especially since people are also looking for those same books and some of them are waaaay in the back. So you get fed up. You close the library. You put away all the new books. You move popular books where they are more accessible and less important ones to the back. Now you're ready to open and everyone finds books faster and you have room for new books to be delivered. Similarly, say you're a car mechanic. You need to change a wheel. How hard is that if the cars constantly driving all over the place? Better to tell them to stop and give you time to do the repair. You can't fix the machines you're using. | 3 |
6d238v | Engineering | Why are most boats operated/captained from the right side, but autos and airplanes on the left? | It has to do with where the rudder oar was placed on boats before fixed rudders were invented. That oar was on the right side so that side was the Steerboard (later starboard) side. The left side was therefore the side that went next to the dock (port side). As for cars. That has to do with the driving practices of wagons. Originally you sat in the middle behind your single horse. As teams of horses got bigger you eventually had them running two abreast. So you had to choose which one you wanted to be the lead. Some countries made the front left horse the lead, some the front right. You sat on the appropriate side of the wagon for the placement of the horse you were directing. That became the side of the car that you sat on when they were invented. With planes you sit in the middle, unless they are large enough to have two pilots seats. Either can control the plane. | 2 |
993vew | Physics | Why can't we capture and store sound energy? | We can - this is how a microphone works. The simplest way to think of a microphone is as a speaker in reverse. To make a speaker, you use a coil of conductive wire with a magnet suspended near the opening. Pass electrical energy into the coil and the motion of the electrons produces a magnetic field. If the electricity has a pattern in the strength of the flow, the magnet will react by being drawn in and out of the coil rapidly. Connect the magnet to a sheet like a drumhead that can transfer this motion to the air and you can create sound waves with the moving magnet. Now in reverse, you can capture a sound wave with a funnel that concentrates the changes in air pressure down to a small surface - put a magnet on that surface and when it vibrates, it will induce a current in any nearby coils. That *creates* electrical energy - which can be detected and recorded to form a microphone. Sound waves don't carry much energy, so it isn't very useful to power something other than a microphone. | 2 |
lhh2j2 | Biology | How do transplanted organs, connect back to the new body? Do doctors reenginner tens of millions (?) of connections back? | Not really. Basically, every organ simply react to chemical signals. When the brain want an organ to do something, he sends the chemical. If you want an image, consider people using firework to direct a boat on the ocean. Green mean go slightly more to the left, red mean slightly more to the right. Blue is a confirmation that you're on track. It doesn't matter the boat, nor the port. As long as everyone knows that code (which is the default one), every boat can arrive at destination, even if ports don't have access to the same pigment. One blue is slightly darker, while another lighter. It's still the same color. Maybe the boat will interpret the darker green as "MORE to the left" and lighter green as "Slightly to the left" but nonetheless, they do as expected. Well organs work the same way. The base composition of these signal is the same. It may not be 100% perfect but it'll get the job done until both the organ an the brain know how to properly communicate. If the body doesn't reject the organ beforehand ofc. | 3 |
erc6k3 | Biology | If bad posture is so bad for you then why does it feel so good? | It doesn’t. People can convince themselves that anything feels good. Being out of shape, being addicted to narcotics, being negative, being isolated constantly, and on and on. Slouching feels comfortable at times but if you go from that to standing up straight and stretching, you’ll get a good feeling that is just natural, as if you should be doing that. Because you should. | 2 |
9njnel | Technology | Why did old cameras record and old TV's displayed images in a more square ish shape, and now the modern ones record/display images a lot more in a rectangular shape? | The older tv format is 4:3 . It is a standard from movies known as the Academy ratio of 1.375:1 that was established in 1932. 4:3 can also be written as 1.33:1 The wider format that is common in movies today was introduced in 1953 in part as a way do differentiate from TV. The common wide format is 2.35:1 The 16:9 format (1.77) of TV today is a geometric mean of the TV format 4:3 and movies of 2.35:1. You can calculate is as sqrt(1.33*2.35)~1.77 It is the formant where you can display both and have the minimal amount of black bars on the sides or above and below. TV later changed to used the whole screen in a 16:9 format. | 3 |
6ndono | Culture | Why are employees expected to give a two week notice prior to leaving their job, whereas employers are able to terminate employees without notice? | Employees can quit on the spot, and unless serious misbehavior is involved, employers typically do try to give employees notice they are being laid off, or more commonly, severance pay. Sometimes circumstances prevent notice from being given. Sometimes people or companies are jerks. | 4 |
d3xjfz | Technology | how a headphones/earphones can still function after going thru both washer and dryer? | Headphones are pretty simple objects: you’ve got two wires going in, a resistor or two inline, then a magnet, sitting behind a diaphragm. As long as the diaphragm doesn’t rip and the dryer gets the electrical contacts dry, everything should still work fine. | 2 |
bz41z1 | Psychology | What causes us to randomly think about people or things from many years ago that we don’t regularly think about? | For me it’s a song, a smell or performing a motion that I have linked to them. Sometimes it’s a place that you go which is “yours and theirs” | 6 |
9kw7k0 | Chemistry | Why does sulfur make the Kawah Ijen volcanos lava blue? [ URL_0 ]( URL_0 ) Why does the color affect the lava in such a way to change its coloration? | The lava itself isn't blue, the sulfur coming into contact with the oxygen in the air burns blue making the lava look blue. The link you posted says it looks normal during the day, and that you can only see the blue flames at night. | 1 |
dryq4e | Biology | why don’t the bottom of your feet get bruised from walking/running? That much pressure/impact anywhere else on your body would leave bruises. Especially larger people? | Because your body is used to it since you've been walking since a young age. Touch your heels, notice the skin is much harder there than on say the underside of your arm or your neck. | 4 |
eukkeu | Economics | How do free mobile games make money when all the ads in the game are from other free mobile games? Is it just a closed loop of game companies paying eachother or are they getting money from somewhere else? | What about games that only monetize with Ads ? | 13 |
9e1ku7 | Technology | How do MRIs work? | Oh wow...a loaded subject. I will try. ANYONE PLEASE FEEL FREE TO CORRECT ME!!! & #x200B; An atom has a certain "spin" to it. It isn't actually a spin but rather angular momentum. For the purposes of this discussion, lets just say an atom spins to the left or right. Negative spin and positive spin. Don't think TOO deeply on this "spin" as a full explanation of nuclear spin is a lot to take in at one time and beyond my comfort level to be explaining. & #x200B; When an atom is forced to change it's spin (in this case by a strong electromagnet) the atom gives off a weak radio wave. In essence, an MRI machine detects those particular frequencies of the Hydrogen atom. We chose H because it is present in all human tissue (except the outer most layer of skin.) So...we tune into the radio frequency of H and we set the body in a large electromagnet (or we can pass that magnet around the body) turn the electromagnet on and off in various patterns. The H atoms give off radio wave s (because their nuclear spin reverses) each time it is influenced by the magnetic field being turned on and off. H is present in all tissues in the body but it is present in varying amounts. This is how we can distinguish the different tissues. This allows us to see things like a tumor (a tissue of a certain density) is inside of a person's liver (a tissue of a different density.) We can also see that an athlete's ACL ( a ligament, a tissue with a certain density) is all coiled up inside of the knee (a cavity) and that's NOT where an ACL should be nor is it the SHAPE an ACL should be. & #x200B; This strong electromagnet is a super conducting magnet and requires liquid Helium to keep the magnet at operating temperatures. | 3 |
6f7heu | Culture | Where the origin of the Southern U.S.A being known as dumb/slow came from and how it has persisted. | The South has always been a very rural part of the country. If you go literally anywhere in the world, there will be negative stereotypes of farmers as dumb hicks. | 5 |
ajtott | Other | Is reading in "chunks" as effective as reading all at once? | You should actually remember the material *better* than if you sat down and read all 100 pages at once. | 1 |
i40q66 | Other | Why do regular, everyday cars have speedometers that go up to 110+ MPH if it is illegal and highly dangerous to do so? | I am from Germany and once used the speedometer to nearly Maximum. I just feared going further because I thought a wormhole would open or sth similar. Btw speed was of course legal. | 16 |
m1fnfq | Technology | How does cryptocurrency like Bitcoin contribute to climate change? I've been seeing lots of articles about how Bitcoin and other cryptocurrencies are leaving massive carbon footprints that negatively affect the climate. But after doing a little research, I'm still not entirely sure how that connection is made? How is crypto more harmful to the climate than actual paper money, or even traditional digital banking? To me right now, it seems like all these Bitcoin = climate change news stories are being pushed by people or organizations that have a vested interest in ensuring decentralized currency doesn't take off. | > How is crypto more harmful to the climate than actual paper money Because in order to spend a tenner nobody needs to spend multiple kilowatt-hours verifying it. I just hand over a tenner to the cashier and we're done. In order to create a bitcoin block and be awarded with the mining reward you need to guess a very large random number. This requires spending electricity to have (most often) your GPU cycle trough numbers until you find the correct one. That spends a bit of energy but nothing to write home about. The issue is that a *lot* of people want to be the one to find those numbers, so collectively over the network there are millions of GPU's, entire warehouses worth of GPU's, constantly running 24/7 playing at a giant lottery, constantly guessing numbers day in and day out. That wastes a *tonne* of electricity. The issue with electricity is that quite a lot of it so far is generated with fossil fuels and therefore has a carbon footprint. Bitcoin has a lot of benefits, but in it's current form with the current amount of demand it generates it's really wasteful. | 3 |
dfo01b | Culture | What the blizzard hate is all about | Blizzard gave a one year ban to (and forced a forfeit of $10,000 in winnings) Chung Ng Wai, a Hearthstone player from Hong Kong. To quote the New York Times: > In a post-match interview with the Taiwan stream of Hearthstone, Mr. Chung, who is known as Blitzchung, appeared with ballistic goggles and a gas mask, protective gear often worn by protesters during demonstrations in Hong Kong. Mr. Chung shouted in Mandarin: “Liberate Hong Kong, revolution of our times,” a popular slogan of the protesters. Blizzard also reportedly fired the hosts who were live during Blitzchung's appearance. | 2 |
6okwzq | Other | Product placement in movies/shows. I've always wondered how movies or shows pick what cars or motorcycles to have in them. For instant,Tom Cruise always seems to ride a motorcycle, does he get to pick it? Is it a bidding system, do they approach the car/motorcycle companies and vice versa? I was not able to find anything on reddit to see if this question was already asked! Still new to the reddit game. Thanks! | The TL;DR version is that just like there are ad agencies that focus on print media, or TV spots, or whatever, there are ad agencies that do product placement. Sometimes product placement is one service among many that an ad agency will provide, but there are also boutique agencies that do just product placement. As to who calls who first, it depends, but it rarely involves manufacturers directly. Manufacturers are the ad agencies' clients. They usually don't get involved until a few steps into negotiations, once both studio and ad agency think there's a deal to be had. Sometimes the ad agency will contact a studio with an offer of free/discounted product(s) and/or cash for getting that product in whatever the studio is working on. The studio will then consult its own projects and producers to see if there is a fit to be had. But sometimes a producer/studio will contact an ad agency and say "Hey, I need product I don't have to pay for," or "Hey, we're trying to patch a funding hole," and the agency will consult its portfolio of clients to see what deals can be struck. Yeah, this is part of what that "Produced by" credit is about. | 3 |
k1dxvv | Biology | Why is your brain making up excuses for you to not start dieting? Title says it, people come up with excuses and doubts to not start bettering themselves even though they know the science behind it but can't seem to accept that it's that simple. For example burning more calories than you consume to lose weight. & #x200B; Edit: People are saying how the human body doesn't like it when it's deprived of food. My main point is the fact that although we want to lose the weight more than anything, we keep doubting and questioning the effectiveness and the end results, preventing us from starting it, with full knowledge of how to do it and how it works. I always thought it had to do with our need to be efficient, and not wanting to waste any of our time/resources. For example we're not satisfied with *any* type of diet, we want the *fastest* and most *effective* one. It seems like if we don't have that, we're not starting to diet at all even if it would be better than doing nothing. | I lost a lot of weight through steady, gentle restriction (200-500kcal defecit per day) the first week or so was hell, I was hungry, irritable, considered quitting. Then when I was happy with my weight and tried to eat maintenance calories I felt bloated, unhappy, and irritable. Humans like habit, human bodies like consistency. Changing up what we do, how we process things is bothersome. A lot of hormones are very involved in the gut so changing foods habits can really affect mood. The trick is to keep with it until it becomes your body's normal, when it learns to balance it's homeostasis around the new energy balance, then it's easy | 7 |
it60o4 | Other | How is it that even babies know if there is a wrong note in a song? How do we ALL intuitively know good pitch and bad pitch when we hear it, even if you are not musical? | Humans are really good at recognizing patterns in things. So in a song you have harmony and a general flow of things going on. A sour note breaks the pattern, breaks the harmony, and it stands out. From an evolutionary perspective most animals have some sort of warning cry that something is wrong, or there is danger. It breaks the norm. So the break in harmony may trigger a repressed instinct or response. | 1 |
bd7fzx | Physics | What does a quark's spin have to do with it's properties? | Probably the most notable property that quarks have due to their spin is that two quarks can't ever be in the same state at the same time. This is because quarks have spin 1/2, and any particle with spin 1/2 has that property. The property is called "being a fermion". | 1 |
7wy2q7 | Other | How do Musicians receive Royalties? Do they just get a check in the mail once a month with their share? | depends on the terms of their contract. whether it be net 30, 6months, or every other tuesday except the 3rd tuesday of the month. there is no hardfast rule. | 1 |
hg8cf8 | Technology | Why are some games' default resolution 1280 by 720? | It's possible that the programs in question are improperly detecting your hardware so it guesstimates that resolution as being within the realm of your system providing at least 60 FPS to hit that standard 60hz refresh rate for vsync. | 3 |
9z2ele | Culture | Why is abortion very taboo in certain countries despite the economic and health benefits? | Simply, because people differ on their answer to the question: At what point (if ever) in human development is a parent responsible for keeping their child alive and at what point (if ever) should society enforce that responsibility? | 4 |
ital1c | Economics | Why is the world in debt? who do we owe the money to? | money is debt. inherently. all money that the federal reserve prints is debt that must be paid back to it as it is a private entity and not a bank. | 12 |
9176bo | Culture | How did the name "Jesus Christ" come to be equated to expressing shock and surprise? | It probably came out of invoking the name of Christ when people were terrified of things they assumed to be manifestations of the devil | 2 |
o4tvxz | Physics | What are banked curves / turns? I've been researching curves and splines for a videogame project of mine. I'm not 100% sure what it means to have a curve 'banked'. It seems to help vehicles with turns on curvy roads, but I don't quite understand how exactly a curve is banked / what it means to bank a curve (visually) / how it helps with turns. I have seen some formulas / math for it, but I'd like to understand the concept before exploring potential implementations. | It means the outside of the curve is raised up in elevation, putting that section of road at an angle to reduce the risk of sliding off due to the centrifugal forces involved when taking turns at high speeds. | 3 |
hmy1we | Economics | Why did churches receive PPP money when they are tax free establishments? | They also employ people. People they can't pay when Sunday services are shut down and the collection plate isn't getting passed around. | 2 |
677gc8 | Biology | If parrots are so smart, why can't they be potty trained? | I had an African Gray. She was not potty trained as such. When she did go she would say "Bombs Away ". | 3 |
cazyfj | Technology | Besides WiFi how does internet connect or use the same servers on opposite sides of the world, Are there like thousands of kilometers of internet lines that run through the ocean connecting different continents? | Yes. Big cables across the ocean floors. In the beginning people used regular phone cable that stretched across the ocean floors but nowadays it lots of very big dedicated mostly fibre-optical cables. | 4 |
6xzmn9 | Technology | Why is cgi so expensive ? | For the same reason movies are so expensive Production value(things on screen) cost money! Take game of thrones - The production costs money because you have all the actors, prosthetics and the costumes and the sets The cgi costs money because you have the actors: like dragons (that literally have to be built from nothing) So they go through a concept phase - then a modeling phase(size and shape) (then a detailing phase) then a texturing phase(color) then a lookdevelopment phase (shaders (how light reacts to the object) example is it shiny meta or rusted metal or skin or fur etc) Now you have the shape of the dragon .... and we need it to move So you rig it! Add in all the bones (chances are you have a rigging system in your studio so this is somewhat automated - but dragons still need wings etc - and kraken need tentacle rigs etc) - All you digital doubles is the actors need scans(of the actors - probably photogrammetry) Now the object can move but it doesn't until someone animates it (or you use motion capture (which still needs some clean up)) Animation is VERY slow - it's a process of moving a puppet around inside the computers so that the dragon feels heavy and angry etc.... such a unique skill set Now the background!! Start with concepts then mattepaintings then cgi sets - snow, simulations for cracking ice, fire etc Add dothracki on horses (start from the beginning to make these) - add castles and unsullied and mountains and clouds! Ok now you need lots of computers to render the damn scene and the technology is constantly changing When I started I used 3ds max and vray Then Maya Houdini and mantra and vray Then Houdini and arnold Now Houdini and redshift And the computers need to be replaced every 3 years or so because of RAM and GPU CPU etc Add the fact that all of your artists have gone to school for around 4 years to learn all this so they make in average around $80,000/yr (that's a guess after being in the industry for 10 years) Low end is around 30,000 to start and 150,000-200,000 when supervising And you can make more on the flagship shows at major studios People in the industry complain a lot but It's a good living - it becomes more of a lifestyle because you're always working on learning new things - but it's also never boring and it's a way to use your art school diploma to make a living - plus you can say "I worked on that show" For whatever that's worth! | 9 |
iabnwf | Biology | How do our bodies know not to fall off of the bed when we are sleeping? I have fallen off a bed once or twice, but I have also slept on docks and high spaces without any problems. I know I move a lot in my sleep, so how does my body know when to stop moving in a certain direction? | It isn’t that it knows not to move a certain direction, it is that it is literally unable. Your brain stops talking to your voluntary muscles when you fall asleep in a term called “sleep paralysis”. In a deep sleep, your brain is racing but sleep paralysis keeps all that activity in the brain. | 2 |
6sb8si | Culture | Why was/is pizza the most popular delivery food in the west? Is there a reason that pizza in particular became a popular delivery food as opposed to sandwiches or hamburgers? | It's mostly subsidized ingredients which are kept dirt cheap in the west - flour and cheese. | 6 |
6h5ri8 | Culture | Why do protestors block streets and highways? Wouldn't this turn a lot of people away from their cause? | If they didn't block streets or highways, would you ever pay attention to them??? It gets them noticed. | 3 |
awvmbg | Physics | How do explosions tear limbs off? | Hold a quarter peeled banana out a moving car’s window horizontally then vertically. Now try it with a 3/4 peeled banana. The limb’s connective tissue can only resist so much perpendicular force by the air before tearing off. The longer the lever(limb) the higher the force multiplier at its base connective tissue. | 2 |
casjq6 | Technology | What does your phone do with all of the excess energy it gets after charging to 100%? | Modern phones don't overcharge, by design. Its not safe to do so and could cause damage to the battery or other safety issues. Generally when they reach 100% they stop charging and actually slowly discharge their power down to about 95%, then charge back up and repeat. | 1 |
6jl7hr | Culture | Why is burning religious books considered a hate crime? URL_0 Here's news about a burned Qur'an. Why is it a hate crime when it's just a book? I get that it was burned most likely because whoever did it hates Islam, but, at the end of the day *its a book*. It's not like they burned a real live Muslim. These types of hate crimes confuse me. | > It's not like they burned a real live Muslim. There's a quote by the German-Jewish writer Heinrich Heine: "Where they burn books, they will eventually burn people." Just over 100 years later, members and supporters of the Nazi Party publicly burned books written by people they considered "degenerates": Jews, communists, political enemies, anyone they didn't like. And not long after that, people they didn't like were first incarcerated and then exterminated. Yes, "it's a book". But it's important to note what the act of burning it represents: it's intended as a message to Muslims. It shows more than mere contempt for a pile of paper: it is an expression of hatred towards a group of people based on their religious beliefs, and a veiled threat: "Leave now, or this is what we'll do to you." It's not really different than the KKK burning crosses in people's front yards, or Jihadists burning American flags (or, in one famous incident, Turks burning a French flag thinking it was a Dutch flag): the fact that it's a mere artefact isn't the point. It's about what it expresses. | 3 |
6eehaz | Other | What happend to all those video games that based on movies why did they stop making them ? like i remember when i had my ps2 every movie that was big i used to get a video game of it , Wall E, UP , ratatouille , bee , barnyard even fast n furious tokyo | The cost of developing this kind of game has gone up over time, especially if the features of modern gaming platforms is implemented. In addition, the reputation of movie games has been shot. A combination of rushed schedules and tight budgets usually meant the final product was not very good, so sales were typically weak. As such, nobody wants to invest in this kind of concept any more for computers and game consoles. However, mobile apps are still frequently used for movie tie-in games | 1 |
bqjc6n | Other | What are the degrees of murder ? | 1st degree murder is a wilful, premeditated, unlawful killing. 2nd degree murder is wilful, unlawful killing, without premeditation 3rd degree murder varies by country but is similar to manslaughter, being unlawful killing without intent to kill, or by allowing death through negligence. (This is not manslaughter, that’s a separate law, and some countries do not have a ‘third’ degree murder) | 3 |
fd3wql | Biology | Why is a coinfection not possible when it’s the regular bug versus the new bug in the same host? | You have to be more specific. A coinfection is absolutely possible, and even common. But sometime a microbe can consume all the "food" or Simply already occupy the space needed by the second microbe, making you resistant to the second infection. | 1 |
6oly32 | Other | How is it that we know more about the far reaches of space then the bottom of the ocean? Surely if we can survive in the vacuum of space, we could easily survive in the bottom of the ocean? | Well, I suspect it's just an expression and we don't REALLY know more about space, but take those things into account: Space is big, but also have A LOT of the same things. Now, most of those things can be described with physics. Other way around, we can learn about physics from studying space and the behaviour in space. Look up at the sky a clear night and try to count the dots. That's all things we can see and with a telescope we can often tell what they are (often with a little use of physics). So when we say we know a lot about space that also means like "we know of xxxxx amount of planets!", but that's basically just us keep looking for more planets. We already know how to find them. As for the sea, I'd imagine there is less interest, as aliens are more interesting than another fish for most people and where space have a chance of learning humans some new physics (gravity was explained due to looking at planets) a new fish doesn't often give us much useful knowledge outside of the "well, there is another fish". The most useful thing you can get from that is information about evolution, and while that is indeed interesting it doesn't give us anything the way physics gives us things like new technologies. | 5 |
d9dl4q | Biology | How did early humans survive winters without things we have today like warm clothing? | We didn't. Early humans lived in Africa, in area's that did not need warm clothing to survive year round. The prevailing belief is that clothing was developed long before humans began to migrate out of Africa to less warm climates. Edit: corrected statement to match lice study. Clothing appeared 170,000 years ago, and humans began to migrate out of Africa 100,000 years ago. | 5 |
8bdcai | Biology | how did humans end up developing allergies to synthetic substances? Things like latex allergies and such confuse me | When you develop an allergy, it has nothing to do with whether the allergen is found in nature or not. All that matters is that it is something not found inside your own body. An allergy is your body's immune system reacting to something harmless as if it were something bad, such as a parasitic worm. A lot of the methods your immune system uses to kill germs work by killing anything alive, so that is why it hurts your cells as well. This is acceptable because if your immune system didn't do this, you would 100% for sure be dead. But this is where the bad symptoms of allergies come from. When your body develops an allergy, immune system cells such as T cells and B cells react to it. B cells (they produce antibodies) and T cells react to anything that isn't made by your own body, which is how they can react to things like latex. Your body has to purposefully suppress them in the digestive tract for example, so you don't have an allergic reaction to literally every food. If something goes wrong with the suppression of immune responses to things that are harmless, you get an allergy. Because once the B cells have detected something that matches the antibody they make, they will stick around in your body for decades, if not your whole life. If it were a disease that caused it, this would be good, because it stops you from being infected a second time. | 1 |
67hh17 | Other | What is the importance of the French presidential election? | It is seen as a barometer of the direction of European politics in general. For decades Europe has been on a trajectory of closer alignment with each member state, but the UK voting to leave the European Union rather put the brakes on that. Several countries have politicians who see the European Union as an entity that lessens their own sovereignty. That's why so many right-wing parties have had strong results. Coupled with the Trump's ascension in the US, you're looking at a lot of the most powerful countries in the world having the potential to be very closely aligned, politically speaking. Marine Le Pen's father, Jean-Marie, was the leader of le Front National (a very hard-right political party), and she took over. this is the closest that any politician this far right has got to the French presidency, and the election there is seen as bellwether for Europe. If le Pen wins, the European Union could conceivably evaporate. Brexit, Le Pen, Trump and others represent the kind of anti-foreigner rhetoric that suggests banning muslims or closing borders to refugees, so France also going the same way would reinforce this idea of isolationism on the global stage. | 4 |
5vtmdz | Technology | Information Tech professionals of Reddit... How can you tell what people are using their work computers for? Someone in my office got fired today for unethical use of their work computer. How does IT know what is going on? Does clearing search history/browsing info/ cookies/ ect really do anything? What information can IT departments tell about computers and how? | In my last job we had software which would scan the machine for any images which may have been porn. We also got a monthly report on the web monitoring software which would highlight questionable websites visited, time spent on youtube etc. ELI5 - IT departments can monitor everything you do on your computer, it just depends on the company policy how indepth the IT admins check it. | 2 |
9r7tgt | Biology | What is the point of poisonous fruits? Aren’t them supposed to be edible so seeds can spread easier? | You know how humans love to eat grapes but grapes are really poisonous to dogs? Well all fruits are like that, tasty to some species but poisonous to others. It’s because a plant wants to make its fruit really appealing to whatever species will spread the seeds but doesn’t want other species to eat it, so it makes it off putting to them. | 7 |
kvyjec | Other | why is the history of the world/civilization studied using BC/AD? | Because that's the system that was commonly used in Western countries. We need some point in time to start counting the years from, and it is completely arbitrary - choosing to start 2021 years ago is as good as any other point. However, since the BC/AD system has been widely used for the past 1200 years, there was no reason to change it. | 6 |
7w6kzt | Other | Why do squatters have so many rights? What is the history of squatters' entitlement? | Adverse possession just means that if there is a rich millionaire and he buys say like 20 acres of farm land and lets it decay and abandons it then you as a competent farmer could move in and try to make it functioning again. However you can't do it in secret and you have to use the land or property as it was clearly intended. The rich millionaire has every right to assert his legal authority and evict you but if he doesn't in a certain time frame (ranging from 5-20 years) then possession switches to the farmer who kept the land functioning and profitable in that 5-20 year period. Like another comment said its within societies interest to encourage proper maintenance and usage over decay and disrepair. And if an adverse possessor can do that, then he has a legal claim to the property. | 2 |
6237k7 | Other | Why does coffee make me high strung and twitchy but tea doesn't? | Coffee is brewed with beans that have been roasted. When the beans are roasted the caffeine in them is broken down from complex polyphenol molecules into simple caffeine molecules which are easier for your body to digest. This means the caffeine hits you very quickly, and in turn provides a short lasting burst of stimulation. Tea, on the other hand, is brewed with leaves that have simply been dried, not roasted. The caffeine is is still bound up in complex molecules that your body metabolizes at a slower rate, providing a longer lasting, but less intense stimulation. Green tea also contains an amino acid called L-Theanine, which has a calming effect. It works well with caffeine to take the edge off the stimulation, hence no jitters. URL_0 URL_1 | 2 |
6tn5qh | Engineering | Why/how distinct gear upshift sound with CVT? I rode in a 2017 Honda Civic with a CVT. While it was accelerated hard to 60, I heard and felt what certainly seemed to be distinct gear upshifts. But it has a CVT. So, it supposedly has a Continuously Variable Transmission and does not have distinct gears. So, ELI5, what was I hearing and feeling? *edit: Thanks for the replies. It seems that Honda added in simulated gear shifts. Which is dumb. Seems like there should be a software hack to remove them! | How bout buy a manual gearshift for real gear changing euphoria ? You know...actual shifting | 20 |
acqb9v | Biology | How is it that docile and defenceless animals such as cows, sheep etc. survived natural selection? | Natural selection isn't about who's the strongest or who's the smartest. That's all orthogonal, and it's why "survival of the fittest" is a strongly disliked term by modern biologist. It's entirely about how well you can reproduce in an environment. Cows and sheep may not be able to hunt, but they *don't need to*. Eating grass is their adaption. They can get food with minimal effort. They can bang, have a bunch of children, their children can have plenty of food. Even if half of them die from predators, that's better than the predator who nearly starves every day and whose children die after they break their leg. | 5 |
lajrlg | Biology | When vegetables in the fridge are about to go bad, how does cooking them make them last a few days longer? Whenever I have something about to go bad, I cook it. But how does that stop it from going bad for a while longer when it’s still getting older? | It kills the bacteria that have been breaking down the food. Basically, the cooked food without bacteria or more accurately dead bacteria is more sanitized than the previous state of uncooked food with bacteria. It's a similar principle of putting food into zero degrees Fahrenheit freezer, which stops all bacterial growth. | 1 |
lqvd9o | Other | How do reality show interviews work? | I was on My Strange Addiction about a decade ago so I can give you perspective from there... Basically they did multiple long form interviews on multiple days. We shot for a week, during that week we had a few on location interviews basically just summarizing the situation and how I felt, all very casual, (OTF or OnTheFly). The biggest were the 2 seperate nearly 3 hour interviews where they asked me the number of different questions multiple times as well as reframing some questions. 18+ hours of footage for an 11 minute segment. Got the impression that they just wanted as much footage as they could to edit however they wanted, and were trying to specifically give me lots of room to breathe so they could go wild in the editing room. One interview was at the first of the week and the second was at the end, but I wore the same clothes and was asked many of the same questions. Continuity is important on a shoot like that, but unfortunately they had issues with their audio so I kind of sound like a robot in the final version. But they also didn't have time to do it again so it went to print. So to ELI5 - production cruise will tell you to keep a set of clothes and a lot of reality TV show interviews are focused on repetition and trying to get provocative comments. I really watched my wording and you can tell in the video that they stitched multiple sentences together to get me to say what they wanted me to say, it was kind of embarrassing to me because most people couldn't tell that it was not edited. A lot of the people they hire for stuff like this have experience with acting, or the therapists they hire have done video work before so when it comes to multiple people being interviewed for a reality show they often know what they're doing and have been on set before. They have a Rolodex of people who know how to behave on camera. Unrelated to MSA: I did some production work for a reality show a long time ago about putting gay guys through boot camp (stupid show) and that involved interviews, but it was more the Bachelor/Real World kind of interviews where they setup a booth and do a round of them on shooting days. Alcohol was always served. Now if you're talkin about live reality shows like Wendy Williams or Jerry Springer, the interviews there are much more fast and the hosts are much more aggressive (I was on Bill Cunningham and another that didnt goto air) and oftentimes there's producers either on earphones or with cards on the sides trying to direct the conversation a certain way. Some of the shadier shows will tell you to "GET ANGRY" or "DROP THE BOMB" etc to try and stimulate drama. That's all the time I have for now but if you have any other questions feel free to AMA. Edit: speech to text corrections | 8 |
5r361e | Other | Recovered alcoholics can't socially drink for the rest of their lives but recovered sex addicts still have sex, but learn to have a healthy relationship with it. Why isn't it the same for alcohol? | I used to be an alcoholic. I know, now, what alcoholic drinks provided me with; numbness. I couldn't face my painful childhood flashbacks because I was not 'there'. Yes, I sought therapy. Five years, I and my therapist took me to relived my trauma. I drink a glass of wine or a bottle of beer at supper time. | 44 |
l3temz | Technology | Why can't we just read the secret ingredients of coca-cola off the ingredient label on the back of the can ? What's secret about it ? | If you look at the recipes for Coke (and Pepsi) 'do it yourself' plans you will see that the flavor comes from a pretty complex mix of quite a few flavor ingredients. Even if they published what they were trying to get the precise combination in the precise amounts would be very difficult. | 5 |
69y6z9 | Biology | what is the difference between migraines and normal headaches? I get migraines normally out of the blue, while headaches happen when I am irritated. | I suffer migraines, and I can tell you that the medical science community has about as good a grasp on this as you do. The biggest difference is the onset of multiple symptoms as opposed to the tension felt in the head during a headache. I will also experience aura symptoms and double vision immediately prior to the onset of a severe migraine, along with sensitivity to light, sound, nausea and intense throbbing in the head and neck. When you have a migraine, you don't mistake it for a headache!! | 1 |
6uped1 | Other | How do news crews record all the people at rallies / out in public without their permission when Google Maps/Earth has to censor faces? What is the difference between Google Maps/Earth driving through a town and capturing people on their cameras, and the news putting live video of people out in the public squares during these rallies on their channel recently? | Google doesn't *have* to censor faces. There's no legal requirement. They just to it to save themselves the headache of people suing them to have their image removed because it shows them at a strip club, or at their mistress's house, or something else like that. They might not even *win* such a lawsuit, but it would be a drain on Google's resources. So they just preemptively blur all faces (and license plates) to skip the hassle altogether. | 2 |
a2kiyu | Technology | Why do phone manufacturers let their customers set the date and time on their phones to before the phone's manufacturing date? | There are standards in the industry for timekeeping. I can't remember how this one goes but pretty much it started at all 0s, and counts up by 1 for each second that's passed since I think January 1 1970... Probably wrong on the date but if you Google "the 2038 problem" it's about this specific timekeeping standard. Anyway, they pick a particular standard and just use it because it works, no need to reinvent the wheel. And by having some standardised timekeeping function it's easier than having to program the Date of Manufacture into all the chips as they're made because you have to keep changing the programming all the time, better to just use a standard format and allow the phone to update itself when it connects to a tower for the first time. | 4 |
dig230 | Chemistry | Why does dinging the top of a glass bottle with another glass bottle make the drink inside explode? You know, like in all those viral videos? | When the bottle get hit it moves down so fast that the liquid get's left behind and creates an empty space at the bottom (called cavitation). If the liquid is carbonated the gas will come out of solution super fast to fill that void, but by that time the liquid will have already filled it back. Now all that gas that has been pulled out by the near-vacuum has nowhere to go but up, pushing a lot of the liquid with it. As for non-carbonated drinks, the cavitation created at the bottom will pull the liquid so violently that it may pop the bottom of the bottle right of, which can be seen [here]( URL_0 ) at around 1:50. | 3 |
76jxgh | Culture | I keep reading that Greeks didn’t have a word for blue and humans couldn’t see it until modern times. How is it possible that our ancestors didn’t see the color blue? What did the sky look like to them? The ocean? | The greeks had a word for dark blue and word for light blue. They could see the color blue. That being said color is a pretty relative concept, you can make colors disappear by going deep enough underwater (red first) and you just see other colors instead, usually yellow, then shifting down the color wheel, or grey if there isn't another being emitted. | 5 |
6grzdh | Technology | - why do trains care what you charge in their power sockets? Does it make a difference if i charge my laptop or my toothbrush? I'm currently on a virgin train in the UK and they have a sign next to the power socket which reads "laptops and mobile phones only". | Because laptops and mobiles don't draw much current (typically 1.5-3Amps) Although it's a standard 13A socket, the electrical supply couldn't actually support everybody pulling 13A for hair straighteners or fast-charging battery banks. | 6 |
7ukktz | Technology | Why does FM radio sound better than AM? | Essentially 2 reasons The Traditional AM band, before the X band is added is just over 1MHz wide. 1) AM stations are spaced 10 Khz apart in the Western Hemisphere, 9Khz apart in the rest of the world Any time you mix two frequencies together you get 4 our, the 2 original the sum of the two and the difference of the 2 This means that if you are in full AM or Full FM as opposed to Single Side Band Suppressed carrier, on a 10kHz channel you can only get 5 kHz of audio bandwidth In 9Khz areas, it's 4.5Khz audio. While that does not sound so bad for spoken word it is not really enough for music to sound decent. The FM band in most of the world 88-108 Mhz is actually 20 MHZ wide, and each station has 100Khz for it's use. The way FM works it ends up with about 15 kHz of audio bandwidth. 3 times that of AM, and there is more bandwidth left That bandwidth is used in several ways One way is to do compatible stereo. Meaning that a mono radio will produce a mixed down mono sound and a stereo radio will produce stereo sound on the same station provided that the station has it's stereo encoder turned on Here is where the single side band comes in The Main channel is L+R or mixed down Mono there is in an unused part of the channel at 42kHz a signal that is L-R the left channel only. From this your stereo radio figures out R-L the right channel, that L-R signal is single side band so it does not affect the other side of the carrier leaving that for other things At 19Khz there is a narrow signal known as a "Pilot" The radio is designed to never pass that signal to the audio section. What it DOES do is essentially tell the radio when the broadcast is in stereo so it can light the stereo light and turn on it's stereo decoder circuit. Because of the wider bandwidth of the transmission the transmitter radiates the same power but does not produce quite the signal strength of a mono transmission. Another reason why the station may not want to broadcast in stereo is because the signal-to-noise ratio is not quite as good that way.The radio itself simply needs more signal to decode the stereo signal with any success. This is WHY the modulation on the stereo pilot signal is purposely so low, The radio is SUPPOSED TO revert back to mono mode when it can't get a strong enough signal for viable stereo. This is all 1960s technology. In the 1970s and 80s the stations were able to make improvements in their signals in another way Until then all transmitter antennas were either horizontal polarity or vertical polarity. In FM where wave lengths are all around 3 meters either was viable On AM where wavelengths range from about 600 meters to about 180 meters only vertical is practical Vertical polarization only actually discriminates in favor of car radios and portables and against the antennas of most stereos Horizontal polarization actually sounds a little better because most sources of static are vertically polarized. Circular polarization which is both vertical and horizontal at the same time was developed in the 1970s and deployed throughout the 1970s and 80s It DOES help with signal intensity and gives it fewer "holes." Another feature developed by the radio manufacturers around the same time and deployed mainly on car radios but occasionally some higher end portables is one that actually varies the radio's own receiving bandwidth by a couple of Khz as you drive around and the signal strength varies to keep the signal as strong as possible. That's why you may hear variances in audio quality as you drive around. Another reason is the radio circuits themselves. The detector is the circuit inside the radio that actually separates the audio intelligence from the radio frequency carrier. It still rings true today that to build a good radio start with a good detector. Cut corners on the detector if you want to build a piece of shit! Because of the fundamental design of the different detectors used in Am and FM FM detectors employ what is known as the "capture principal' whereby when there are two signals heard on the same frequency the detector will tend to "lock in" on the stronger signal and completely exclude the other At one time this pretty much insured that FM had almost no interference. Now especially up and down the two coasts ant through the Great Lakes region The FCC is trying harder and harder to essentially pack 5 pounds of shit into a 4 pound can No station is really interference free any more. As a result it's common to drive around and hear a car radio jumping from one station on a given frequency to the next. When that happens what is REALLY going on is that the two stations are so close in signal strength that the radio can't tell which is the stronger and it keeps bouncing from one to the other trying to lock on but unable to ever do so. Another problem with AM audio quality is that radio manufacturers know their customers would rather pay for good FM sound will build a decent FM stereo radio and stick a crap house AM receiver in it | 14 |
htksct | Biology | why do we look for water when we look for alien life? Why are scientists always so excited aboud liquid water on a planet or moon when it comes to finding life? Can it only be water? And why is water so inportant for hosting life? | If water is liquid, that means the surface temperature is probably within the range of 0-100C, and we know life can survive in that range. It's by no means a certainty, but finding liquid water gives you decent odds that the planet is capable of supporting life. | 3 |
hs3md5 | Engineering | How do the dispensers at gas stations know when to stop disbursing fuel? | Most gas nozzles have something of a pressure sensing function in the tip. Basically if any fuel but the fuel going out gets close the tip of the nozzle, it feels it and stops. | 3 |
migoh5 | Biology | what actually signals our bodies to cause diarrhea and how does the body decide when it has evacuated enough to stop diarrhea? | The one type I haven't seen mentioned yet is the dreaded period poops that all women know about, which is mostly diarrhea. Prostaglandins are largely responsible for that. Prostaglandins aid in uterine contractions, but can actually effect other organs, including the digestive tract. So in addition to cramps, many women also get diahhrea around the onset of menses. | 11 |
i4axi5 | Biology | How do people grow seedless watermelons? Like where do they get the seeds? | They still come from seeds. It is sterile tho, it can grow but won't reproduce. It is like using the seeds for one time only. | 6 |
iw4z03 | Technology | How do games like Among us suddenly blow up overnight and become mainstream with millions of downloads after two years of no real success? | I believe that it was Twitch streamer sodapoppin that played the game with a few people and then later on invited more Twitch streamers to come play with him. Those streamers realised how good the game was and that it created good content so they also began inviting other streamers. Eventually it got big and the viewers thougth the game looked fun and also bougth it. | 2 |
dfirmr | Economics | How is money that's confiscated in the "drug war", cleaned and allowed to go back into circulation? I was binge-watching some episodes of Live PD and in one of the episodes an officer says that they purchased some marijuana from a dealer and upon a warrant to search the house, they found and identified the same money they used to purchase the marijuana. On a bigger scale, like thinking US in general and bigger drug-busts, how is money cleaned, cleared and allowed to go back into circulation? | Others answers are right about where and to whom the money goes. But I think OP asks what do they do about drug residue or police marks on the actual paper bills. The answer is you can literally put them into a laundry machine. I know from experience US dollar bills survive laundry just fine. You can wash dollar bills with soap and sponge, but it is not practical for the amount of money they get from drug raids. Besides, police marks are invisible to naked eye, and safe to touch. | 3 |
avcpyq | Culture | How do swear words become swear words in the first place? | I don’t know if this has already been mentioned but evolutionarily speaking, the reaction when you stub your toe in be might and tell a curse word developed because we need to alert ourselves and others to a danger. Long ago certain utterances or sounds were likely used in the case of danger or harm and as such used in a reaction fashion. Now when you curse in reaction to pain or danger it is an echo of that. | 11 |
m3y6rc | Biology | How did current olympic champions surpass the ones from decades ago so much? Are they training harder? or are athletes today just physically better? | To make it real short, science has figured out how to better train an athlete. Genetics teamed with science. | 25 |
demzpf | Economics | The business model of banks. How do they make money? | Interest they pay to depositors is less than interest they collect from borrowers. Checking accounts have zero interest, savings accounts might have 1-2% interest. But loans from the bank are 10% interest or more. The difference between 10% and 2% is so large because is has to pays for the loans that are not returned, employee salaries, computer systems, interest-free safety reserves that bank has to keep at the Fed (Central Bank), etc. | 4 |
kghnj3 | Other | How is it that we can want things so badly, but once we have them, we lose interest? | Hedonic treadmill URL_0 The good thing is that it works the other way. A couple weeks after a major negative event and most people go back to their previous level of happiness | 4 |
dgd62t | Other | is intelligence a default grant or knowledge based trait ? | Being good at something comes from training and repetition. How much training and repetition depends on how much you apply yourself, but two persons with the same application would still not yield the same result. Some people are better at learning some things compared to others, this is also a skill that can be trained to a point, but just like you will never run as fast as Hussein Bolt, you might never be Einstein smart with all the training in the world. In the end there is a genetic cap to every single thing your brain or body can do. You can only train to get as close as possible. | 2 |
80daid | Biology | What is the difference between Cardiac Arrest and the Heart Attack? | Heart attack is when blood flow to the heart is sudden interrupted. Cardiac arrest is when the heart suddenly stops beating by its own accord. Heart attack is a circulation problem; cardiac arrest is an electrical problem. | 4 |
bhp3ig | Physics | Why do protons determine the characteristics of atoms? Why is it that you can add many neutrons without it making much of a difference, but if you add a single proton the atom behaves very differently? | Because the protons help the atom hold onto electrons. The configuration of these electrons controls how the element participates in chemical reactions. Most of the "behavior" you're referring to is chemistry. | 1 |
iql8rm | Chemistry | How can the source of a fire be determined when often times everything for miles around has been burnt to a crisp? Ignoring somebody who either saw or admitted to causing the start of one, how is there any evidence left to determine what caused a fire? | Also taking from my ass, but forest fires generally have a very identifiable start point as the fire started there and went down wind. It’s not hard to go up wind and find the start and look for a lighting strike, campfire, gender reveal party or meth den. House fires are different. I still don’t have direct knowledge of this, but I have been told that fires that originate in the house usually have some evidence of where it burned the hottest because at the start there is more oxygen in the house. This is a good clue to start. Also, metal doesn’t really melt in temperatures associated with a house fire, so a broken gas line etc will still look like a broken gas line. A candle might be more subtle. | 8 |
ai3qek | Technology | Streaming services subscriptions | There's no universal guidelines for prices. You can charge for anything as long as people buy it. Cable has advertisements *AND* a buy-in because they can. People want to watch those channels enough that they are willing to endure both. Streaming services began to be popular by undercutting those prices. | 2 |
igc4yj | Biology | Why is it so satisfying to sneeze, to the point where if you don't when you felt like you were about to it's seen as an annoyance? | The desire to sneeze builds tension. The sneeze releases the tension and the contrast feels good. It doesn't feel good if you are sneezing 100 times a day. | 9 |
epujot | Engineering | Just watched Ford v. Ferrari. How was the 1964 GT40 able to achieve a top speed of 210+ when modern supercars are still barely pushing 200? | Because we would rather only have professional drivers breaking over 200mph. But it is pretty funny watching rich guys ball up expensive cars. | 21 |
6ad4o1 | Engineering | Where does electricity come from My four year old asked me where electricity comes from. I explained from power plants that generate it in different ways and they send it to our house via electrical lines. I also explained that there are different ways that we generate electricity (solar, hydro, coal, etc) but I couldn't simply explain how electricity gets created from heating water to electricity. Anyone able to boil that down? (pun intended) | Some people have done a good job of this but left out a couple important parts. A turbine is used to spin a rotor (think of something like a long axle) that is connected to the generator which actually spins the magnets in a copper field which creates the electricity. Historically these turbines have been mostly steam powered, where a power producer will burn something like coal, trash, or even byproducts of oil; use the heat from the burning to create steam. The steam runs through a series of blades attached to the rotor which spins the generator Present day, a lot electricity is created as part of a combined cycle. A combined cycle starts with a combustion turbine (oftentimes Natural Gas). A combustion turbine will take a fuel (NG) and compress it, burn it, and use the resultant heat escaping to push blades on a rotor, which is attached to a generator. The exhaust from 1-3 natural gas turbines then heats up steam which will power a steam turbine. *Apolitical commentary coming* This is largely why coal jobs are disappearing and likely won't ever come back. Natural Gas is easier/cheaper to extract from the ground, burns much more cleanly, and creates energy more efficiently due to the combined cycle. *Fun trivia* Everyone in the power industry pronounces the word 'turbine' as (ter-bihn) not (ter-bine). The word comes from the french word turbinem (ter-bihn-um), which meant swirling or spinning water, and eventually the /m/ fell off, leaving the word we use today. | 4 |
hnndt0 | Technology | Why does "on hold" music on a phone sound like it's under water? | In addition to the technical problem of insufficient bandwidth for music, there is also the legal issue of licensing. A business must have permission to play a song and because they don't want to keep track of every time it's played they will go with a royalty-free (pay one, unlimited plays) license. A royalty-free music track is way more expensive that the same track sold to a consumer (for generally less than 1$). When all this music was originally on cassette tapes they would have made [copies of copies of copies]( URL_0 ) of the cassettes as they wore out. Every time a digital storage [PBX]( URL_1 ) started to die or was upgraded they would have placed the telephone handset on a laptop's microphone so some intern could record the hold music and load in in to the new system. | 5 |
fgm356 | Other | - What are DJ's actually doing up there with all the knobby twists, record turns, and switch flips? Seems like absolutely nothing is changing to the music when they're doing all of this. Is it just for show? | This video is a good demonstration of what basic record switching/transitioning involves URL_0 Some DJs do much more and actively mix several tracks, levels, filters, effects. Others literally have a playlist and are there to provide a more visual source for listeners. | 7 |
cjhl64 | Other | In the photos you see of nebulas, galaxies etc. What exactly does the coloured smoky areas represent? Is it just light or something cooler? | > Is it just light or something cooler? Why not both??? This is going to be a long answer. In a nebula, the colours come from the glow of different ionised elements under different circumstances. Hydrogen is the most common element in nebulae and is found everywhere. There's also sulphur ions (sulphur that has lost one electron), found near the edges of nebulae, and oxygen ions (oxygen that has lost two electrons), found near hot stars. Interacting hydrogen emits red light. Sulphur ions also emit red light. And oxygen ions emit greenish light. Now, because hydrogen is so common throughout the nebula, and sulphur is common near the edges, if you just left the colours as they are the whole thing would just appear mostly red and bland. So, the majority of images of nebulae actually use *colour mapping* to create more interesting images--that is, the colour normally emitted by an element is mapped to a different colour to make it more distinct. The red from hydrogen is assigned to appear green, the red from sulphur is left as red, and the green from oxygen is assigned to appear blue. You will notice that this matches the typical red-green-blue (RGB) breakdown used in the vast majority of modern screens and image processing. This particular method of mapping is called SHO (sulphur, hydrogen, oxygen--corresponding with red, green, blue); there are others, like HOS (where hydrogen is red, oxygen is green, and sulphur is blue) and SNH (sulphur is red, nitrogen is green, and hydrogen is blue), but SHO is by far the most common. The result is some spectacularly colourful images in which the light emitted by various elements is more distinguished. Now for galaxies. Galaxies are a bit more straightforward because, well, they're made up of billions of stars and other light-emitting things, so as you might imagine most of the colour just comes from that. Blue spots in galaxies are areas with young, hot stars, which tend to glow blue because they're so hot (just like the flame from your kitchen stove). Yellow spots are older stars that burn yellow/orange (like our own Sun). Red spots are nebulae--as mentioned before, they're the red from dense clouds of hydrogen. | 2 |
gm6vkh | Biology | It's stated that many vegetables contain "anti-cancer" or cancer fighting compounds. How exactly do these compounds work to prevent cancerous cells from forming? | First off, I want to mention that oxygen naturally reacts with compounds in the body and make them more reactive. As such, they can react with all the other cell components, such as DNA, and damage them. DNA damage leads to cancer. Vegetables contain what are called 'anti-oxidants' which are compounds that quench and/or sequester the reactive oxygen compounds. They prevent cell damage and therefore, they can prevent cancer formation. | 2 |
aohljp | Chemistry | Why is mercury so dangerous? | It's dangerous, but don't believe the hype. If you touch it a couple times, roll it in your hand, you're not going to get cancer and die. Don't eat it. You'll be fine. | 9 |
70utqu | Culture | Why do all sign language interpreters make silly faces when they sign? Are the faces apart of the language, or is it just kind of a natural human expression that people that can hear do as a compensation due to not being able to verbally communicate while they sign? | Facial expressions are an important part of the language. Some signs always go with a particular facial expression, while others can go with multiple facial expressions to indicate different meanings. For example, when asking a yes/no question, your eyebrows go up to indicate it's a yes/no question, similar to how in spoken English, your inflection goes up at the end of a question and down at the end of a statement. Also, describing facial expressions as "silly" could be perceived as a bit insulting. They are certainly much more exaggerated than those of most hearing people, but that doesn't make them silly. | 5 |
64zsyr | Engineering | Why are batteries like AA and AAA almost always inserted in opposite directions for polarity? Why not just create wiring so they can be inserted in the same direction? | A few inches of wires costs a lot more in parts and labor/machining than a few extra square mm added to a shim of metal (and the enlarged metal shim can actually reduce the number of parts in an assembly). For a lot of purposes you would find this kind of setup, every saved penny in manufacturing costs contributes a huge amount to the profitability and final cost of the product. | 3 |
7zv966 | Culture | Why is Denmark (1 silver medal in Winter Olympics history) so terrible at the Winter Olympics, while its Nordic neighbor Norway, has 367 medals all time? | Even though Denmark is a northern country, it doesn't really snow that much there. On top of that they don't have any mountains. | 28 |
ayldhw | Engineering | why does the temperature of the shower water change so much with a tiny push? | Because the hot and cold water have roughly the same pressure, and come to the shower through similar pipes. But the knob that selects how much of the hot water and how much of the cold water to combine isn't actually a sensitive regulator that can finely control the flow of each type of water. It's more like a [circular hole]( URL_0 ) that opens to let more water through. A "tiny push" could rotate that from a small sliver to half that hole being open. | 1 |