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the Boeing 737 Max uses a computer to 'fly against nature'. What does this mean? | Modern aircraft use something called fly by wire. Basically there is a computer that is constantly adjusting the plane to make it do what the pilot wants. If the pilot does nothing then it makes it just fly straight. This is really useful as it takes a lot of strain of the pilot having to constantly adjust things. Also... |
If the Gregorian Calender we use today only took effect in the 16th century, how does this impact the accuracy of dated historical events prior to then? | Julian calendar used for 15 centuries before then is basically the same thing as Gregorian aside from leap year correction - years ending in 00 are always leap years in Julian, but are only leap years if they divide by 400 in Gregorian. Converting that one isn't hard, now if completely different calendar like Mayan or ... |
Does “burning in” brand new audio gears such as headphones and speakers actually work? | The important bit is the suspension of the cone, the [black rubber part] in this drawing. This part of the speaker needs to be flexible in order to allow the membrane to move, but it also needs to be firm enough to keep it centered. Some speakers use materials which are a bit too stiff when they come from the factory, ... |
Why do milk jugs in the US invariably leak from their cap, but not other liquids? | Milk jugs are weak because they aren't made to hold pressure. I don't know for sure, but it's possible that the milk jug producers made a decision that it was better for them to leak a bit than to have a really great seal and let the stuff build up pressure and explode later if it's left out. |
What makes “unsolved math problems” so difficult to solve if you continue to answer/follow the formula? | Something to understand is that math isn't just formulas and doing 1+1=2. Math is fundamentally an exercise in logic. XKCD puts it quite well - Math is just applied philosophy. Fundamentally you can say math is the science of logic. It is about figuring out if a statement is true or not and proving that it is true. Man... |
Radon Test Report is 3.2 pCi/l ... What does this mean? | This is below the limit of 4 pCi/l, but just barely. If it's new construction, I'd expect it to have some sort of venting system to carry radon from below the basement to the outsides. It's often a low power vent fan connected to the sump pump's basin. If there is such a device, it might not be working, unless you are ... |
In movies and books, people with terminal end-stage cancers are almost always symptom free until they drop dead one day. How realistic is this? | Cancer is a disease which grows in an organ. It can damage or displace the organ. So its effects depend on where you get it. Brain cancer will have obvious effects on mental capacity. Stomach cancer won't. The standard symptoms of cancer like hair loss and nausea are not symptoms of cancer but cancer treatments that ar... |
What causes the grogginess or difficulty concentrating when you have a cold? | I Huh. I always had the exact reverse reaction. When I have a cold I become hyper focused. I aced every single exam that I had with a cold when I was still a student. And I'm much more productive at work. It's like I shutdown all the emotional processing. I don't need motivation to do things, I just do them, indefinite... |
How do WIFI enabled lights work? | It is constantly drawing power for the internal controller to receive signal from WiFi. On an app, if you command it to turn on the light for example, it will send data to the light to turn on. But the controller uses very little power, therefore saving electricity isn't a concern. |
How long does it take for food to “store as energy” (fat) within a human body? Why does the body burn muscle instead of fat when starving? | This video explains it all, but skip forward to the 17:00 minute mark for a graph of the rates at which sugar, carbs and proteins are converted to energy , and if you watch the whole video you will see that the body doesn't burn muscle for energy & #x200B; [_URL_0_] |
Why is it so much harder to move our pinky fingers with precision than the other ones? | It's not, or at least it shouldn't be in normal anatomy. The hardest finger to move independently should be your ring finger . If you are having trouble with a pinky it could be anything from lack of practice to a mild ulnar nerve issue. If you have normal feeling in that finger just work more on developing the muscles... |
Why does the US only have two political parties that count? | The US has almost never had more than two relevant political parties, and it's been the Democrats and Republicans for over 150 years. That said, the parties have changed dramatically over the years - the Republicans were the liberals when they were founded, and the Democrats conservative, but things began changing pret... |
How can a hot computer shut down and completely turn off the fans? Wouldn’t the heat hurt the components? Seems like they should keep running for a few minutes.. | When the computer turns off it stops running electricity through the components so they stop producing heat. They can't magically get hotter internally so I'm not sure what the reason would be for a continuing fan cycle. |
what does "power cycling" a modem actually do? Why is it always 10-15 minutes? | Power cycling resets the router. By that I mean the state of the software that's running on it. After a reset it starts anew. Sometimes software can get into states that the programmers didn't thought to be possible and it can cause errors. Like variables having incorrect values. It's a commonly used trick for most har... |
How do APIs work? | Come", and "Stay"In simplest terms API is basically just a computer program, designed to accept a defined set of parameters and in return send back information. A weather API may for example specify, send me your longitude and latitude, and I will send you the current temperature from the nearest NWS station. |
How can there be thousands of satellites around Earth, if there are only a handful of rocket launches every year? | Well there's been almost 100 for last few years. And some launches end up with multiple satellite deployments in single launch. A launch by India 2 years ago launched 100 satellites on a single rocket |
Why do children prefer drawn movies/series over live action movies/series? | For the same reason they like Barney and Teletubbies even though they're not animated: bright, contrasting colors and big, simple, usually rounded shapes. For the same reason they like picture books instead of a collection of Annie Leibovitz portraits. Children -- particularly babies and toddlers -- don't have the same... |
Why must some medications be taken with food, some without food, and others don't matter | These medications fall into several categories: With food: this is due to the fact that if you have an empty stomach when taking that medication, the stomach will react the same way as if food enters it and begin digestion, and will begin to break down that med. The med when broken down will irritate the stomach lining... |
How does propulsion work in outer space without atmosphere? | For every action there is an equal and opposite reaction - If a rocket exhausts something ' backwards' then the rocket will be propelled 'forwards' with the same force. |
Why does denser housing construction seem to make housing prices go up? Shouldn't the opposite happen? | the only reason you build denser housing is because land is at a premium. if you have room to expand horizontally and expand then you do. if you don't, then you build up. so in areas where everyone has 2 acre lots the houses are gonna be much cheaper than in a place where everyone is living in a 1000sqft condo. |
If our eyes don't see in frames per second, why can car wheels seem or other spinning objects appear to have framerate-like effects? | because your brain can't process everything your eye sees. there's a limit to how much optical information your brain can process. it's like your gpu is running at 200fps, but your monitor is only 60 fps. your eye can see really high fps, but your brain needs to convert those images to something meaningful. |
if an electron is a field surrounding a nucleus instead of a particle orbiting a nucleus, what does an atom with multiple electrons look like? | The electron is not a cloud or a field. We describe quantum particles with something called a wave function, which is a probability density function, a lot like the bell curve. The wave function tells us where we're *likely* to find a particle. The wave function for an electron orbiting a nucleus can get very complicat... |
Why is paying a chartable organization money to pay staff/people to allow your child into a college a crime, but donating directly to that college to allow your child to attend not? | Quid pro quo. There's a difference between being a golddigger and asking a man for money in exchange for sex. This guy Sanger was taking money and bribing college staff while claiming he was running a nonprofit foundation, which means there was also a lot of tax fraud. George Lucas legally donated hundreds of millions ... |
What exactly do game studios have to do to port a game made for console to PC? | It's all about the **Game Engine** these days. The engine is what runs the game, it handles things like drawing the geometry, adding the lighting, taking user input, moving the character, animating the enemies etc. Very few games are written without a game engine. So if the game engine exists on the new platform, it's ... |
Why do people use the color 'green' for greenscreen and not any other color? | They do use other colors actually!!! Green is the usual though because it doesn't match any natural skin tone or hair color, meaning no part of an actor will be edited out through chroma key. If there is a green costume or prop, a blue\xa0screen will be used instead |
Why do noises you hear at night seem louder, even in the same conditions as the day? eg. silent house with nobody there. | There is a muscle in your ear that holds a small bone in place to dampen sound. When there is lots of noise, your ear reacts to dampen sound to prevent damage to your ears from too much noise. That's what happens when you get used to a noisy environment. When it gets quiet, your ears become physically more responsive t... |
How is it possible to wake up (day after day) within 5minutes before my alarm goes of in the morning? | Your body has an internal clock. Your body also doesn't like being woken up in a harsh fashion. Your body gets used to waking up at a certain time. It adjusts its own internal timer to wake up natural before your clock does it in a harsh fashion. Congrats, you just used negative reinforcement to teach yourself to wake ... |
what are the effects of antidepressants on a person without depression? and what is the chemistry/biology behind it? | You'll get side effects, but that's about it. They don't do anything if you are not depressed. |
Every time a ambulance passess to our road, when a ambulance is approaching. I hear siren loudly. When its going away, i hear siren noise less. | The siren is pointed towards the front of the vehicle. It is to let everyone in front of the ambulance know it's coming so they have time to react and move", 'Doppler effect, change in frequency as it approaches and as it passes the wavelength is increased . Sorry, this is my first post on this subreddit. Someone can m... |
What is the difference - the DIFFERENCE - between aliasing and anti-aliasing? | The concept of aliasing involves a problem created by sampling periodic information. Imagine for a moment a wheel with a single mark on it. I'll be spinning the wheel and you'll glance it at once per second . Now, when we run this experiment, you observe that the mark is always in the same place. This leads you to conc... |
How does a zip file compress data? Why don’t we make all files stored automatically compressed to save data? | Ooh! I was just about to write a zip compressor for a CS class, so it's very fresh in my mind. A very basic form of data compression is one that starts at the beginning of your data file and records any repetition. This works okay for things like ASCII text files and some images, but when your data is fairly random, it... |
How do vehicles detect how far you can go on your current amount of gas? Wouldn’t sensors not work due to the gas sloshing around? | First thing to understand is that there are sensors EVERYWHERE in modern cars. If something is moving, pumping, pulsing, whatever, there's a sensor attached to it somewhere. If you just accept that those sensors work as designed and don't get bogged down into how each one works individually, then the idea of calculatin... |
What in electricity gives you power? | Electricity is caused by the drift of electrons small particles through the metal. These electons very frequently bump into atoms which causes the atoms to shake which is what temperature is. Heat atoms up enough and they start to emit light. But that is just one example. In general electrons don't like to be close tog... |
How is Pi programmed into calculators? | It's simply hard coded. Calculators can only use a limited amount of digits anyway, and you don't need more than 10 digits of pi for any significant calculations. |
AM & FM frequencies. | Other than FM and AM being modulation techniques , the reason cars receive only frequencies in those two bands is because of regulations that prevent commercial radio transmissions from being sent on other frequencies. So the car's radio is only built to receive in those two bands and not others. |
Why are there always a bunch of super long infomercials on tv only at hours when no one would be watching tv? | Those time slots are cheapest. ALSO, infomercials are trying to get you to buy something that you probably don't need. When are you more likely to comply - when you're well-rested, or when you have insomnia? |
what exactly is net nuetrality? Is it a law? Can it expire? What does it entail? | Imagine Bob owns the highway. Bob wants to make sure Bob's Pizza company is always first, so he sets a speed limit of 80 MPH for Bob's Pizza trucks and cars, and sets a speed of 40MPH for Jim's pizza business vehicles. Jim can't compete because he can't get pizza delivered as fast, and eventually goes out of business. ... |
why do whales breach so violently? I understand they need to breathe, but putting their whole body out of the water and crashing all of their weight down seems excessive. | Perhaps weirdly, it's something that [people don't really have an answer to]; there are a bunch of theories that have some level of support, including getting rid of parasites, demonstrating power , breathing if the seas are rough and they can't just pop their blowhole out, or just screwing around for fun. There are a ... |
why do bridges not form potholes but normal roads do? | Bridges can get potholes. If the asphalt deck cracks and busts you'll get potholes. The same can happen to concrete decks, but not as likely. Plus they're overall better maintained and inspected/repaired. As others have said there's no subsurface to give way and create weak spots. Generally it's just freeze/thaw activi... |
is ignorance of the law ever an excuse, when society has more laws than anybody can possibly remember? | Yes, assuming you are talking about United States laws, there is situations where one can argue ignorance as a defense. I believe they are usually regulated to situations where any reasonable average person wouldn't be able to understand it or know of it's existence. For example, there are lots of tax laws that people ... |
Why use essential oils? | They smell good. If you like the smell, and it can't hurt you, and you can afford to buy them, then enjoy yourself. |
Why would a Helicopter have no problem carrying thousands of pounds at a low altitude, but cannot carry the same weight at a significantly higher altitude? | When people say that 'the air is thinner' at higher altitude, think of it like branches on a tree. Sure, the nice thick branches near the base can easily hold a person up! You could probably jump on them or fit two or three people on a single branch. But the higher you go, the thinner the branches, and the air, get. So... |
If results from mouse models are not applicable to humans most of the time, why are they still used today? | They may not be directly applicable, in that we can't say definitively if a drug for instance works on mice that it will work on humans. But it is at least a good suggestion that could lead to more conclusive human trials. Also mice are cheap and easy to use as test subjects, so they've been studied extensively making ... |
Why do nearly all human to human bite wounds become infected? | The bacteria in the human mouth has already adapted to living in a human, so it's perfectly comfortable in a human bite wound. When another animal bites you, the mouth bacteria isn't comfortable inside a human so it dies easier.To quote an article about managing bite wounds from the Journal of Emergenicies, Trauma, and... |
Pi was recently calculated to the 31 trillion digit by Google employee Emma Iwao. Is there any benefit to calculating pi more and more accurately? | Realistically, they're just showing off at this point. Most things that can be made precisely are going to use three, six, or maybe nine digits of accuracy for any given reason. It wouldn't be realistic to try to build something to even a hundred digits of accuracy because at that point the error would be nearly imposs... |
Why does our normal voice sound different than our voice from a recording? | When you talk, your voice travels from your mouth through the air and to your ear. But the sound waves also travel through your head to get to them, passing through all kinds of squishy bits and fluids, bouncing off of bones, etc. As that happens, all that stuff that your voice travels through changes the way it sounds... |
Why do radioactive materials decay at a predictable half-life yet there’s no way to know when one molecule will decay? | Someone better than me at quantum physics can probably explain better, but it boils down to probability. You can't know what face a die will land on on any given roll, but roll enough times with a die and eventually you'll average it all out. |
Canadians pay less or about the same as Americans in tax rates but get Health Care, how is this possible? | they don't waste all their money on an insanely bloated military industrial complex and increasingly unnecessary boarder security.I am canadian, we get taxed waaay harder than americans. Out west with both taxes we lose 40% ish off any income over 75k or soU.S.: 54% of discretionary spending on military Canada: 8% of d... |
how are rotary autocannons accurate when the barrelsnrotate? Wouldn't the trajectory be skewed? | A few thoughts; The speed of the bullet leaving the barrel is far greater than the speed the barrel spins, so while there may be a slight effect, it is very small. As the gun will fire at the same point in the rotation each time, any slight Skye can then be counteracted by the aim of the gun - if the bullet leaves the ... |
why aren't there any small sea mammals? | The ability to regulate body temperature is key for mammals, and ocean water can be quite cold. As part of that need to regulate heat, sea mammals evolved to have thicker, more fat-lined bodies, which hold in heat better than small, thin bodies. The other reason is related, and is based on the fact that the larger a bo... |
How can wee see things 46.5 billion light years away, when the universe is only 13.7 billion years old? | Everything is shrinking, relative to the size of the universe. You can argue that the universe is instead expanding, but everything is relative, so lets say that we are all shrinking. If thats the case, then our ruler used to measure how far apart things are is getting smaller as well. But the distance we need to trave... |
Why is it that the slower I go in a car, the tighter the turn is? Even though my wheels are at the exact same angle. | I'm not science savvy, but from what I know it's not necessarily that you are going slower, but that your are not excellerating; when you're turning you're essentially redirecting your momentum, so that momentum is still trying to push straight ahead while your wheels are cut to make a turn. Thus, it affects how sharp ... |
Is a tractor a *category* of big machine, or its own individual thing? (Or both?) | according to [Wikipedia] > A tractor is an engineering vehicle specifically designed to deliver a high tractive effort at slow speeds, for the purposes of hauling a trailer or machinery used in agriculture or construction. so based on that I'd say it's a fairly broad category", 'I’m not sure if I would call them a cate... |
Why does dejavu happen? | From what I understand it's caused by a momentary delay in sensory information reaching your consciousness. BY the time your brain is processing the scene/sounds it has already stored them in memory, so it recognizes the scene as something it has seen before and tells you about this. |
Why do beverages from a glass bottle taste better than the same beverage from an aluminum can? | As far as I know, sometimes taste depends on amount of CO2 in the drink, and usually there is a bit less of it in glass bottles than in plastic/cans. Additional CO2 is added to latter to rise the pressure inside the package to make sure it withstands rough handling during transportation. Try to damage plastic bottle or... |
how do WhatsApp keep being online? | WhatsApp is owned by Facebook since 2014, so technically they don't need any revenue to stay afloat. However they are making money by getting data, which they can sell and/or use for advertising. Supposedly WhatsApp uses end-to-end encryption which means that while the company can't see the contents of your conversatio... |
How does dish soap remove any "dirt" from dishes? | Fun fact: the way most bacteria are designed, the soap actually rips them apart. As someone else explained, one side of the soap binds to oil while the other binds to water. The keratin in/on our skin is resistant to this reaction, while nearly all of our organs inside ourselves are not. This is why its dangerous to sw... |
How does blowing wind to the wound slightly reduces the pain? | pain and very light touch receptors are the same. so you're giving the pain receptors competing information. there are only so many of them and they can only fire so often. so making some of them do something else will lower the pain. |
Why do electronics get hot? | Because whatever it is they're doing, they're not perfectly efficient at it. Your CPU loses some energy as heat whenever you switch a 0 to a 1 or vice versa, and there are billions of transistors in a modern CPU, switching billions of times per second. That adds up. |
How do viruses get into a computer? | Installed at factory Malicious USB device USB device that was ever plugged into a compromized machine. Installing software from sketchy sources. various vulnerabilities in all kinds of software. Really, best you can do is only install software from sources you trust, keep that software up to date, and monitor CPU and n... |
Why do electronics usually require 2 batteries instead of just one bigger battery? ie: 2 AAA instead of 1 AA. | An AA battery is bigger in capacity than a AAA battery but both are at the same voltage. Think of voltage as water pressure and capacity as the amount of water in a water tank. You're lifting water into the air with a water tower so that you can get water pressure to run your shower. An AA battery would have a larger w... |
What would the crew of a WWII tank be facing inside once they were hit? | Smoke and fire from the fuel and ammunition. Ammo can cook off when struck, not necessarily exploding but cooking like fireworks. Explosive force from the round itself can knock the crew around if not outright kill them. Debris and shrapnel bouncing around inside of the tank. Even if the tank wasn't penetrated the forc... |
Can juice and tea be a good hydrating alternatives to water? | It doesn't matter where you get the fluid from it's all good. The only studies showing otherwise are those funded by bottled water companies and they're usually on a small scale and not peer reviewed. |
When cooking pasta, why do you have to let the water boil before putting in the pasta, why can't you do it right away? | With the exception of fresh egg noodles. you don't even have to boil the pasta at all. [_URL_0_] I've found that opaque noodles leach a lot more starch into the water than translucent noodles so results may vary depending on the brand of pasta.you don’t have to wait for the water to boil. who told you that? |
What happens when a compass is in space? | It depends on where you are. Some planets have strong fields, some have weak ones. If you're around Mars, you're too late, the field is gone there. Head over to Jupiter, the magnetosphere there is larger than the Sun. You just need to be in the general area to get a direction from your compass. Of course, a compass isn... |
How do other animals see light from lightbulbs? | ~~Argh, there's a phrase for it. It's not phase continuity, but it's something similar.~~ **Flicker fusion.** The idea is that your brain/eye blends quick flashes into a single beam after a certain threshold. And here we probably just have a currently unanswered question. There's no reason to think that this threshold ... |
Why do the edges of flat panes of glass appear to be green and not transparent when viewed directly and not at an angle? | The glass itself is faintly blue green. This is caused by small traces of iron compounds. The is very difficult to remove completely as iron is one of the most common elements in the Earth's crust. Silica sand dug out of the ground is the most important raw ingredient in glass. For many purposes the green is desirable ... |
How did ancient libraries work before the Dewey decimal system? | Get ready for a post Dewey Decimal System. I've seen libraries in Arizona that are abandoning the Dewey Decimal System. It's basically organized like a Barnes & Noble. Books about cooking are here. Books about science are there. Etc. In fact, I think they didn't even bother reshelving the books, so they are in the same... |
How can water be so much heavier than O2 even though only one atom is added on? | Because their new hydrogen friend allows both hydrogen bonding with other water friends, and it gives it a dipole moment. It's helps them squeeze together more tightly and be stickier. |
How did the Greeks translate into Arabic, Chinese etc. without knowing the languages? | Go travel to a place where they don't speak your language. You'll adapt. Most probably by learning to communicate with hand gestures and body language. |
Why does Russia seem to have an inordinate amount of big meteor impacts? | Remember Russia is a rather large country, geographically. It's a big target, so it gets hit a lot. Meteor strikes happen all over the place, but because most of Earth is open ocean, we don't tend to know about them. Furthermore, Russians have a culture of using dashcams on their cars , thus they tend to capture meteor... |
what caused the iconic old dial up internet tone from the 90s? did someone design that sound digitally or is that some sort of analog tone generated from hardware? | If you've ever gotten a call from a fax machine, it'll sound familiar. That's the actual audio being send through the phone lines, being used to encode the data that on each end, gets turned back into a digital signal. |
Why when driving do objects seem to move slower when seen from the windshield vs seen from a side window. | Perspective. Imagine being on a long straight road with no obstructions in sight. If you look in front of you, it'd take a very long time before they disappear from your sight since they're traveling parallel to your line of sight; they'd essentially need to cross over the horizon, which makes it look like they're movi... |
How are names translated in sign language? | The basic explanation goes like this: They just make them up. Because names are basically arbitrary noises that don't mean anything, people who speak ASL and other forms of sign language just create a hand sign that they feel is representative of their person. Or, they will simply spell their name to the person they ar... |
Why don’t they pre-shrink clothing that shrinks in the wash? | Others have already mentioned in general terms why items might not be pre-washed. So I'll just add that natural wool items specifically will continue to shrink every time they are machine washed. The process is called felting and is caused by the fact that wool, like all hair, has scales at the microscopic level. We ma... |
Why does English have so many different words for groups of animals? | There was a book written in 1486 called The Book of Saint Albans' where we get many of the collective names. It is a book about hunting, falconing, and fishing. Apparently around that time it was fashionable to come up with whimsical names for groups of animals and people. The book proved popular and the names have stu... |
how people can have eye colors such as blue and green but not orange or purple? | The human body can create two different pigments. The first is melanin which has a brown-black color familiar in people with dark hair. At low levels is has a dirty yellow to yellowish grey color. The second is pheomelanin which has an orange red color which is found in people who are redheads. This pigment is not prod... |
How are we able to find things in the universe that are billions of light years away? | From what I understand a lot of distant objects are found based on their gravitational effect. We long ago worked out how gravity works in space and how to calculate their impact on other astronomic bodies. Given this knowledge, if you locate a star and a planet, and you notice that the planet's orbit is, say, elliptic... |
How skiers and other athletes can make landing after falling great distances. | What hurts when you fall a long way is the sudden stop. These people land on slopes that are steep enough, and keep sliding fast enough that they don't suddenly stop, which means they don't feel the same impact as say, hitting a wall at that speed. I'm big into these kinds of sports and we always have to take into acco... |
How can a software be open source and secure from hacking at the same time? | Imagine a vending machine with a 2-bit CPU and a program that just says. 1 WAIT FOR COIN 2 DISPENSE SODA 3 GOTO 1 If the company publishes this code, there is nothing a hacker can do. It doesn't matter how many ethernet ports are open to the world, because there is simply no path through the software that will make it ... |
What exactly happened in Watergate? | Most of these answers are kind of wrong or scrambled People around President Nixon's administration and re-election organization bugged the Democratic National headquarters in the Watergate building in DC. They got caught. Nixon definitely helped cover up the connection of these guys to the administration. He went so f... |
What would it take for the UK to stay in the EU, and how likely is it? | It would take a reasonable government instead of people just trying to get to the power. So unless there's elections, it's unlikely. |
How do flushable wet wipes stay intact before being used? | Flushable != Dissolvable. These things cause massive sewer blockages precisely because they do not break down very easily. Recently a 'fatberg' consisting mainly of fat, wet wipes and tampons was found in a sewer in Sidmouth, UK that measured 64m long - longer than the Leaning Tower of Pisa is tall.They don’t dissolve ... |
Why did I instantly feel the need to throw up while eating breakfast? | Maybe the combination of yogurt and sausage didn't agree with you? Are you stressed about college classes? You may have triggered IBS from stress. Try taking a probiotic that contains a patented strain called Howaru. You can find it on amazon.Does it only happen with breakfast? You may have a gastric ulcer or something... |
Why do the President, members of Congress, school teachers etc pay taxes instead of just making less tax free salary? | Somewhat, however it'd be really difficult to calculate their pay because just like everyone else, you don't know your exact tax liability until you file, as you haven't filed all your deductions. Also, efficiency has nothing to do with anything. The government could just as easily automatically file your taxes for you... |
How is it possible for 2 devices to communicate without wires?! Bluetooth, WiFi, telephone...?! | Actually, fairly similarly to the way they do with wires. When you've got a digital device talking to a digital device over a wire, you're translating the digital information into electrical signals and transmitting it over the wire, where it's re-encoded on the other end as digital. Wirelessly, it's basically the same... |
How do you work out the combined probability of 2 events? (Presuming I know the probability of both) | If you have two events that you know the probability of, the odds of them both coming true is the product of the two multiplied together, expressing them as a fraction or decimal, not a percentage. for example, if X is 20%, and Y is 30%, the odds of X and Y both coming true is .2 x .3=.06, or 6%. Put another way, it's ... |
What benefit do stores receive for giving cash back to customers? | If you are referring to withdrawing extra funds from your debit card at the checkout. One benefit to the store is reduced cash load. Cash in the store is a liability. Every time someone asks for cash back, it's like the store depositing that money in their bank. If the store could get enough cash-back requests to cover... |
How is the umbilical cord connected inside the developing baby, and what happens to those connections (veins/arteries) after the baby is born and the cord is cut? | As far as I know, the blood vessels in the umbilical cord are connected 5o blood vessels in the lower intestine of the baby. When it's done developing, the blood vessels in the lower intestine connect inside the stomach and the vessels on the outside are no longer needed. After the baby is born and the cord is severed,... |
Aside from the obvious caffeine content, how do energy drinks work? And is it possible to become addicted to them? | Sugar, is the thing you're craving. Recovering alcoholics are sometimes told to avoid sugary drinks as it may help relapse |
how come people can't eat raw food but other animals can? | Because we've evolved since we started utilizing fire. Cooking meat makes it easier for us to digest as well as makes us less likely to get a disease. We also get less nutrients from raw meat which would be less beneficial if we wanted to evolve to support our brains and have more energy for complex thinking as we do n... |
When you turn the key off in an ignition switch, what does that do to tell the engine to stop being “on” | The Ignition in a car cuts the electrical power to the spark plugs and the fuel pump. The engine dies soon after because it can't sustain combustion any more. Cars get electricity from an alternator attached to the fan belt, and from the cars battery. Smaller engines like those in your lawnmower have a different type o... |
When two pieces of a broken bone begin to heal and bond back together, is the bond stiff, but brittle, or is it more like a glue, slowly getting thicker and stickier? | Probably relatively soft. Bone healing starts with formation of cartilage, which is firm but much more stretchy and soft than bone. This grows from both ends of the fracture until it meets in the middle. This tissue will then slowly ossify, forming spongy bone first, which is also weaker and softer than normal bone. It... |
How were/are the elements on the periodic table created? | [Stellar Nucleosynthesis wiki]. Basically, chemical reactions involve the electrons; they pair up with electrons from other atoms, and the respective atoms get stuck together, sort of. Nuclear reactions involve the nucleus. The nuclei of two different atoms get combined, or a nucleus has some extra neutrons or protons ... |
if salt will make you dehydrated, why is salt water good for dehydrated persons? | First of all, you definitely mean salted water, not salt water. Human bodies are all about balance, and so they try to keep a balance between water and things that aren't water. There are a lot of things that aren't water in your body and salt is one of them. When someone dehydrates, the body keeps the balance, so you'... |
What causes the images you “see” when recalling memories? | I'm curious about this too but I'm not able to picture full memories in my head, just brief/fleeting flashes of specific parts. |
If we can see cells with a microscope, why can’t we just keep adding lenses/magnification to see atoms fairly clearly (with electrons etc.)? | Diffraction occurs when a wave passes through a slit. The smallest angular detail you can see is given by θmin =1.22 λ/D Optical microscopes all use normal optical light in the λ=500nm range. If you want to take the human eye for example then our pupils is the lens light has to pass through and our pupil's diameter is ... |
What are the purposes of mirror neurons? | Mirror neurons are useful for understanding other people's actions and developing empathy. Eg, you see a kid fall down and start to cry. With mirror neurons you can understand that the kid is in pain, can imagine being in the same pain yourself, and are inclined to comfort them. Mirror neurons also help with learning n... |
Why do some countries import Goods that they already have or make in their country? (e.g. food, petroleum products , jewelry and others)? | It depends on the specific good, but there's generally a good reason. In most cases, it's because people don't treat different products in the same category interchangeably. The US imports French wine and also exports US wine to France, because wine drinkers don't think a French wine and a US wine are equivalent. Corn ... |
How do PhD/Doctorate programs work? | It depends on the school/faculty/program really. Despite the differences, the program will usually be 4 years long or so. Speaking from the arts end, you'll usually complete a year's worth of seminar courses, and have the remaining time to complete a dissertation. A year or two in you will also be expected to complete ... |
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