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Could the expanding universe conjecture be a misinterpretation of redshift?
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Reddening due to absorption has a different effect than reddening due to redshift. It shifts the spectral makeup of the light rather than shifting individual lines, which is observed. Furthermore, the same conclusions about the expansion of the universe can be reached by measuring the anisotropy of the cosmic microwave background.
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The top post covered parralax well , but it looks like there isn't a good explanation of red shifting. From an earlier post, you seem to understand the doppler effect and how it relates to velocity. From parralax, we know that further away galaxies are moving away from us faster. If we assume this holds, we can model the universe is expanding and the rate of that expansion is increasing. If we know that light from farther away galaxies take longer to get here, we know that farther away galaxies are older (than we see them now). Older parts of the universe are redshirting more than younger parts and we can confirm this with *standard candles. * A standard candles is a term for a super nova (or other physical event) that has a fixed luminosity due to the nature of the event. If it has a given apparent brightness, we can know how far away it is from another means.
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How often do we replace all the cells in our body? (Or: how long before an entirely new me?)
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Technically never. Many of the cells in your body do not have a regeneration capacity. The most common example of this would be heart cells. If you get a heart attack, some of your heart cells die, and they are never replaced. Typically, in the lab, if we are culturing any normal mammalian cell, they will divide once a day during logarithmic growth phase. Hypothetically, if every single cell in your body decided to divide (which it wouldnt), you could replace all the cells in your body in one day.
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The other answers get to the heart of what you're asking, but I wanted to address one thing in your post, namely > I was under the impression that the body slowly replaces all of its cells in a few years. This isn't true at all. There's high cellular turnover in some organs, like skin, but most of the body isn't like this. Entire organs don't get resculpted, generally speaking, and some, like the brain and muscle, are almost entirely comprised of tissue you developed as a very young child (including in utero). For the most part, the body is pretty static, and dying cells are often replaced with fibrous scar tissue rather than with similar cells.
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Why do Italians consider that ordering cappuccino after lunch is rude/offensive?
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Because cappuccino is a breakfast only beverage. It can be tolerated if you use it for a snack mid-afternoon, but usually it's strictly morning beverage. For us Italians someone ordering a cappuccino after lunch is not rude, we see it as "stupid" or a distinction between a foreigner and a local. It's like eating ice cream between pasta and a steak, or a salad after a coffee and bitter. The only beverage after lunch that is tolerated is coffee, maybe with some milk, but even milk and coffee (latte macchiato) is frown upon.
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Not just Italian, many upscale restaurants play uptempo big band and swing. My old boss said that it made the staff move quicker and the customers ate quicker allowing him to turn the tables for more customers.
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In regards to the Donald Sterling situation, isn't it illegal to record a conversation without the other party's consent? Shouldn't the person who recorded it get in trouble?
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The laws for whether it's legal to record a conversation without the other party's knowledge or consent varies from state to state. The federal law is that only one party has to consent to it, but some states go above it. California has a two-party consent law, so it was not legal for the woman to record his conversation. Sterling could sue her, but that would be problematic because he's denied that it was him on the recording. You can't claim you weren't the person talking and then sue someone for recording it. I'm not sure if an illegally obtained recording (by a citizen) is admissible in a criminal or civil trial, but it certainly is legal for the NBA to punish him for the contents of the tape. They aren't bound to any laws about the evidence being admissible or not depending on where it came from.
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Not every place has the same laws regarding recording. My state allows recordings as long as one party knows. In some places recordings aren't allowed for criminal prosecution, but may be used for civil trials. Maybe the penalty for a recording is worth getting that other person in trouble. Even if I can't use it in court, if it is released publicly that information still gets out.
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How cameramen film actors looking in the mirror without getting in the shot?
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There's a few tricky ways they do this. One is green screening an image onto the mirror, or editing out the cameraman in post production. Sometimes, they'll have an empty frame, or a glass window instead of the mirror & shoot the scene through the frame, so what looks like a reflection in the mirror is actually the actor in the scene. Sometimes they'll use really tricky methods for mirror scenes: a deleted scene in terminator 2 had an actor's identical twin mimicking the actor's movements while they were in an identical, but mirrored, room which was connected by a framed window so it looked like a reflection.
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Put something in front of the mirror and pretend it's your actor. Now move off to the side. You can see the object and the reflection without being in view yourself. It's just a matter of positioning the camera the right way. They just change the angle of the camera and actor. The actor doesn't actually even need to see his reflection as long as you can. There are other tricks, too. You can disguise the camera, edit it out, or build a set with two identical, reversed rooms and have a look-alike fill in for the actor from behind.
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How does the new version of Google Earth create 3D images of places?
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It's done using photogrammetry. An aircraft flies over the area to be mapped and takes lots of photographs from different angles. Then software processes the images and to identify points that appear in more than one image. From this, the 3D position of those points can be reconstructed. The result is a large number of 3D points representing the geometry of the area being mapped (like those seen in [this video](_URL_0_)). Another piece of software can then take those points and connect them to produce a 3D mesh.
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A lot of what you see on google maps is actually "orthophotography", not "satellite" _URL_0_ othophoto is really just a photo from the taken from the air. Often They'll have special planes fly relatively low (compared to passenger jets and such), outfitted with cameras. Flying in a grid, they stitch it all together and sell it to google. The actual "satellite" photography does have clouds and fog obscuring various locations.
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What is the shape of a proton?
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This turns out to be an extremely important question. The charge distribution is EXTREMELY spherical. No-one has yet measured any asymmetry in it, and it's known to be symmetrical to at least one part in 10^11 (100 billion). This is amazingly symmetric. For comparison, for the earth to be spherical to within one part in 10^11, the tallest mountain would have to be shorter than 1 millimeter. But physicists are continuing to conduct experiments on protons (as well as neutrons and electrons) to be more and more sensitive. See, ferinstance, _URL_0_ for ongoing work on the proton. The reason why physicists are so interested in this quantity is that different fundamental theories of physics (the standard model, supersymmetry, string theory, etc.) predict different values for the non-sphericality of fundamental particles. Measuring this asymmetry can help us choose between these competing theories.
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Protons and neutrons are made up of fundamental particles called Quarks. Quarks come in 6 types called "flavors". Up, down, strange, charm, top, and bottom. Only up and down are found in atoms. A proton is made up of two up Quarks and one down Quark. A neutron is made up of two down Quarks and one up Quark. Electrons are fundamental particles and have no (known) smaller parts. Beyond Quarks, the other fundamental particles are Gauge Bosons, Leptons, and the Higgs Boson.
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Why is it that after reading the lyrics to a song I am able to understand what's being said more clearly?
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Top down vs bottom up processing. When you listen to the lyrics of a song, you're really on sensory inputs to determine what is being said. You have no information about the lyrics other than what you hear. Your brain tries to process and make sense of this information without prior knowledge or direction. This is bottom up processing. After you read the lyrics you are now consciously and unconsciously aware of what the correct lyrics are. Your brain now has a direction, so to speak; a definite goal or objective, because there is a now a correct way and incorrect way to interpret the lyrics.
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My rational is, that it's kind of like skimming when reading. You don't need to hear every word to know what the song is about, after hearing it before. So you sort of gloss over parts and tune in to certain parts/ the end of the song. Other theory is that it's like when you are driving somewhere new for the first time. It seems longer, then on the way back does. Since you know how long it is going to take.
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If we could harness lightning, how much power would it give us compared to what we get now?
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[100 lightning strikes per second worldwide](_URL_1_) * [500 Megajoules per strike](_URL_2_) = 50 Gigawatts. As of 2008, worldwide power usage was [15 Terawatts](_URL_3_). 50 GW / 15 TW = .33%, so not much if we could capture every single lightning strike. It actually is a lot higher than I expected. If you are just talking electrical power, then we use [2.313 Terwatts electricity](_URL_0_). Lightning could fill 2.16% of demand.
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The main problem with lightning is that it happens so quickly. A bolt of lightning can strike and transfer all of its energy in mere fractions of a second... and then it's over. We currently don't have any technology that can effectively capture that kind of power (without damage) in that short amount of time. Each bolt carries with it enough energy to power a single 100-watt light bulb for about 6 hours. Additionally, lightning is too sporadic and infrequent to provide a reliable source of power.
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How does the body react to cauterized vessels during surgery?
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There are lots and lots of anastomoses in vessels supplying virtually any part of your body and almost no vascularized tissue is dependent on a single individual vessel for blood supply. The microvasculature in tissue also has adaptation mechanisms for both long term and short term changes in blood supply, blood pressure and perfusion of tissue, so even if the blood supplied to the tissue by the remaining vessels are inadequate, the remaining vasculature can compensate for it quite well. If you are looking for a more specific explanation of the adaptation mechanisms or some examples of anastomoses in major vessels I can explain more.
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It all depends on how quickly you gain medical attention, the size of your blood vessels, stress of the patient, and where exactly you get hit. Your body has actually evolved to automatically retract your blood vessels to shunt off the flow of bloo if you are missing a limb, but a cut in one of your vessels doesn't allow them to retract into the body so that you'll quit bleeding out.
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What does the president actually do all day?
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From day to night, Obama's life in the Whitehouse on his 130th day of presidency: 1) Sees to his daughters going to school, workout. 2) Review national security briefing, read 4-5 newspapers. 3) Goes through 10 randomly selected pieces of mail that is sent to him. 4) Senior staff meetings, discussing economics, security, and whatnot. (This is now midmorning) 5) Meeting with Phil Shiliro about the going-ons of congress. 6) More meetings with various topics, depending on the situation. 7) Lunch (Afternoon) 8) Reviews polls of support. 9) Interview with NBC. 10) Sleeps. This is a good representation of what the president does on a day to day business. They're hardworking people, and deserve more credit than they get.
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He does several things. A - He is the executive branch of the government. When Congress passes a bill, it ends up on his desk. His job is to consult his cabinet and then say yes or no to the bill and either veto it or sign it into law. B - He is the Commander in Chief of the US Military. Aside from a few checks and balances from the legislative side of things, he is in full control of our armed forces. C - He's the country's main representative to the rest of the world. Sure, we have ambassadors who handle the nitty-gritty of foreign affairs, but when it comes to making a serious deal with a major world leader and making a good impression in another country, the President's in charge. ninjaedit: remembered another one D - He's in charge of appointing someone to the Supreme Court when a Justice steps down or kicks the bucket
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What is the difference between the Army's Combat Infantry Badge and the Combat Action Badge?
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Only an 11B ( Infantryman) in the Army can be awarded the CIB(combat infantry badge)for being in a combat situation. The CAB(combat action badge ) is awarded to other MOSs (jobs) in the Army that were in combat situations. However, this is a source of great controversy because some argue that the CAB was created to make other MOSs look good and don't really earn it. That's mostly due to the mindset of the infantry but I digress. Sauce: Combat Medical Badge recipient and Army vet.
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Serious answer: The main difference is that the Army tends to deal with combat situations that involved established bases or active ground situations. The Marines tend to deal with guarding naval vessels and institutions as well as being first-on-ground. Essentially, the Marines are "Shock Troops" to deliver an initial strike in order to secure a staging area from which the Army can be deployed and dig in for a lasting campaign. Simple answer: Army stands for "Ain't Ready for Marines Yet." Marines stands for "My Ass Rides in Naval Equipment Sir!" Joke Answer: About 70 I.Q. points.
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Why isn't minimum wage in the US tied to the dollar inflation rate?
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Because a large enough group of politicians believe that raising the minimum wage at all is bad for the economy, so they make sure it can't be raised. Allowing it to automatically be raised is even more egregious to them.
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Well that would defeat the point of the minimum wage. The minimum wage isn't "this is how much this job is worth", it's "this is how much a person is worth, and how much a person needs to *live*." The closest thing to job-based minimum wages is unions, which individually mandate minimum wages for different jobs within them, if the work is unionized. There also isn't a single minimum wage. There's a federal minimum wage, but then states have their own minimum wages, as do some counties and cities. Their wages can't be lower than any of the larger bodies they're in, but they can make them higher. Some states also have tipped minimum wages, where employers can pay less, as long as the employee makes enough in tips to bring their pay up to the regular minimum wage. Sidenote: The "why should fast food workers make $15 an hour when EMTs only make $12 an hour" argument never made sense to me, since it pretends that EMTs wouldn't also be affected by the minimum wage increase.
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why wearing socks inside out is uncomfortable, but the smooth outside of socks look like they'd be more comfortable than the stringy inside
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Do you prefer walking on grass, or on cement? The cement is technically smoother, right? But it's also harder and has less give, and that resistance can feel uncomfortable or even painful. The same is true for your socks. That outside is more solid than the fluffy inside, so it rubs against your skin more instead of just cushioning against it. In addition to that, when you wear socks, their shape warps somewhat to the shape of your feet. If you wear them the wrong way, those comfy worn out spots your feet are used to will be moved and your skin will again be rubbing up against things instead of softly cradled in them.
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Socks are fairly absorbent and pull moisture away from your foot so you don't notice the sweat unless you completely soak through the sock. Socks also provide a barrier between your skin and the show to help reduce blisters from rubbing
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Why are northern countries so much colder than southern ones in relation to the equator?
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> I know there isn't a very large sample size south of the equator That's actually part of it. There's less water on the north hemisphere. And water has a very high thermal capacity, which means that in the southern hemisphere a lot more "heat" can be packed into the oceans that then slowly release it though thermodynamics as the general temperatures fall.
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On average, the world - including New England - is warmer. But one of the patterns that has emerged over the past few years is a very, very deep jet stream that pulls very cold air from the Arctic south. When this happens, the places that wouldn't normally get this air get a lot colder than they usually do - but that cold is compensated by the Arctic being MUCH warmer (by as much as ten degrees) than it usually is.
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How does water heating on a stove rise in temperature at a constant rate, but doesn't turn entirely to steam in a relatively short period off time when the temperature hits 212°F, which is the point at which water turns to steam?
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Due to the ' Latent heat of Vaporization '. Up until 212°F/100°C the energy supplied raises the temperature of the water. Once it hits that value, the energy is used to convert it from the liquid state to the vapor state. The temperature doesn't rise until all the liquid changes to vapor. Think of it like the energy/heat is used to break the bonds that keep it in it's liquid state.
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Steam is transparent and is above 100C/212F. What most people call steam is actually condensed water vapor. When you turn the heat off the liquid is no longer boiling and isn't producing steam, but it is producing water vapor. That water vapor is more visible because it contains small drops of water like a cloud.
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Is it possible to shrink plastic, then bring it back to original size?
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There is no one "plastic", and something like shrink-wrapping is a one-way process. Plenty of plastics that shrink in cold conditions will expand under warm conditions though. Here's a nicely detailed answer with some ascii graphics: _URL_0_
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One method of doing this is called [Thermal Depolymerization](_URL_0_). It involves placing the materials with water into a container and heating it under pressure. The process breaks down the plastic into short chain hydrocarbons (oil) and other constituent components. It has been tested and it does work, however it takes a lot of energy for this process to work.
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Does Daniel Gibson thesis regarding Petra as being "the Mecca" hold any validity nowadays ?
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Not really. There are some historians (e.g. Patricia Crone, who I’m not sure how serious she was about the point or if she was just trying to be provocative) who have argued that the rise of Islam makes more sense in a north Arabian or southern Jordanian context thenthe central Hijaz location of Mecca. This is a pretty fringe revisionist position. That Petra, specifically, was “Mecca” I’m not aware of any evidence for.
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Any idea why Petra came into existence so far from an ideal location?
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On the Wikipedia page for "Koch's postulates" it is stated that HIV causing AIDS doesn't follow from them. How so?
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Koch's Postulates mainly apply to bacteria, fungi, and protozoans. The Postulates require that you are able to take samples from an infected individual, isolate them in culture, reintroduce them to a healthy individual, and recreate the disease. This breaks down for viruses at the "culture" stage. Unlike living things, viruses are incapable of being grown on a medium and isolated. They can only replicate in living cells. If you can't isolate them in culture, you can't be sure that you're reintroducing the correct thing into the healthy individual, so the whole process gains a scientifically unacceptable margin of error. Also, unlike pathogenic life forms, viruses tend to be extremely species-specific, so there comes ethical questions about introducing HIV or other dangerous diseases into healthy humans simply to validate a hypothesis. There are far more effective and ethical means of determining the cause of disease and infection in modern medicine.
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This website: _URL_5_ describes much of the scientific evidence that HIV causes AIDS. An interesting point to bring up is that AIDS/HIV positive patients that are treated with medicines that target the HIV virus itself, NOT the diseases seen in AIDS patients allows patients to recover to more normal, non AIDS CD4 cell levels.
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Why is light affected by gravity?
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Well that's a pretty tough question to ELI5. The answer on that level would be mass bends space-time. The curvature of space-time is essentially what we call gravity. Light has to travel along the curves because space and time are basically related to make space-time by the speed of light itself. Light is basically the thing that measures space-time. You can push something against the curvature of space-time, but light always takes the shortest path through space-time and that's not always the shortest path through space. When space-time's shortest path and space's shortest path are different then light looks to bend when we view it in space. If you look at gravity from the general relativity perspective then its not really a force at all, its just a landscape that things move along. Gravity is just the path that inertia takes things the force is what we see when we're not looking at it in space-time but only in space.
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Short answer: yes. And twice as much as you'd expect. Long answer: gravity is the curvature of spacetime. Light follows a geodesic, which is the closest equivalent there is to a straight line on something that isn't flat. So does everything in freefall.
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Why does the moon look small on my phone yet bigger on my eyes?
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Your camera has a wide angle lens. [so you can get a nice selfe with your friends in the shot] When you point it to the moon it is covering a wide section of the sky at that distance.
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It's all about perception. When the sun or even the moon for that matter is more overhead, there's nothing for us to reference size to so it appears smaller. When they are closer to the horizon, we have a point of reference to compare to so they appear larger.
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Why can animals eat raw meat with no ill effects and humans can't?
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Here are a couple of previous threads on the subject: * [Why can animals generally eat raw meat/uncooked items, but it can make us ill/kill us?](_URL_0_) * [Why can't humans eat raw meat?](_URL_2_) * [Why don't animals get sick when they eat raw meat?](_URL_1_)
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We can eat raw meat, and animals need to deal with getting sick and dying from bad food. Cooking makes it safer and makes some nutrients easier to digest, but we can certainly eat meat raw.
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To what extent do airports test security? Do they try and bring guns on board? False passport?
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See [this](_URL_0_). Homeland has "Red teams" that try to bring guns/explosives on board. TSA regularly fails their controls...
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I've read that (at least in the Shengen part of Europe) passeport scanner automatically check the interpol database (for wanted criminals). Each country might check it's own police database but they are not that much shared (that's how people under surveillance by the counter terrorism could go to Syria after taking a train to another country) For the rest I don't know what they check exactly, Something like making sure that you look-like the same as on the photo that you haven't travelled to weird countries (I am pretty sure that entering the U.S. with an Iranian VISA will yield some questions) and in paranoïd countries like U.S. that your fingerprint matches the one in your passport...
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What is a mirrorless camera?
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SLR cameras have two mirrors (or one mirror and one prism) to redirect light from the sensor to the viewfinder. There's a big mirror in front of the sensor that shines the light up to the pentamirror or pentaprism, which reflects/refracts the light three times into the viewfinder. This is a superior experience for the photographer because he can see exactly what is coming through the lens, without any digital manipulation. Mirrorless cameras replace the two mirrors with a sensor-to-screen system like point and shoot cameras.
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This is controllable in software. Some manufacturers want it to take a mirrored picture so that users don't get confused when looking at themselves -- users *expect* the phone to work like a handheld mirror.
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Do the surgical masks people wear in Japan actually help decrease the spread of disease?
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I'd like to toss in some cultural observations for why these would be worn in Japan even if they don't stop sick people from getting others sick... * Many people have pollen allergies (upwards of 30%), and the masks help keep pollen out. February through May, there's lots of cedar and cypress pollen. [This site](_URL_2_) recommends wearing masks to prevent exposure and even avoid becoming allergic to the pollen. * It's *very* rude to blow your nose in public. It's also pretty rude to sniffle. When you have a cold, masks allow you to let you nose run until you can wipe in private. * Being considerate is a cardinal virtue, and being inconsiderate is a cardinal sin... Masks are one unmistakable sign that you're concerned for others' well-being. * During flu and cold season, they're also sometimes worn as a precaution by healthy people who don't want to *become* sick, in case they actually work as a germ barrier.
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Surgical masks are worn when they're ill. It's a courtesy to others to not be coughing or sneezing infected mucus all over the place, and it helps prevent disease transmission. It's a great idea and I wish we would do it here.
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ELI4: "curled up" dimensions?
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Imagine that you lived on a cylinder, and you could move up and down along the cylinder, or around it. Then imagine that the radius of the cylinder gets smaller and smaller, until you don't even notice that it's curved anymore, all you notice is the ability to move up and down along the length and it just seems one dimensional. Only really small things would still notice that that extra dimension is there. Also touched on [here](_URL_0_).
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Either the extra dimensions are curled up (compact), or you are prevented from moving in them because you are confined to a lower-dimensional D-brane (braneworld models). In this case the particles of the standard model are open strings whose endpoints are attached to the brane and so cannot move in the dimensions orthogonal to the brane. Many popular models for string phenomenology combine both of these elements, placing various D-brane in compact dimensions; the standard model particles are strings stretching from one brane to another near the point in the compact dimension where the branes intersect. > We wouldn't perceive them simply because we don't exist in them. That doesn't make sense; you need a mechanism to confine you at a certain position in the extra dimension. In flatland, this is magic. In the real world, being constrained to live in a lower-dimensional subspace requires a reason. D-branes are the incarnation of this mechanism in string theory.
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What's the difference between monetary base and money supply?
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Monetary base is what your central bank has available to lend. Money supply is the currency in circulation. Due to the creditmultiplicator there's more in circulation than the central bank can secure.
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Currencies like the Dollar and the Euro are controlled by *central banks*, which have different ways of putting more money in circulation or taking it out. For example, to add more money they can simply create it (sometimes literally printing it) and use it to buy things (like debt). To decrease the money supply, they can increase the amount of money other banks are required to keep on deposit at the central bank, or sell assets they previously bought. Generally, central banks adjust the money supply to keep a healthy balance between inflation and unemployment. (Edit: clarifications)
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If food takes longer than 24 hours to digest, then why do I take a massive fiery dump within an hour or two every time I eat spicy Asian food?
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The spicy food can irritate your stomach and make your bowels react by clearing what ever is in the pipeline, so to speak.
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your body is trying to protect you from these hot foods, its a defense mechanism. you might love spicy foods, but your body doesnt. your nose produces mucus which is something your body makes to protect it...
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Why can cheese age for years but get moldy after a week in your fridge?
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when hard cheese ages, the outer layer could grow mold. but it doesn't penetrate into the inside. soft cheeses are coated in a wax layer to protect it from random elements.
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Pre-Shredded cheese is usually surface coated with cellulose (wood pulp) and Natamycin which is is an anti-mold agent. Block cheese will have an exposed surface once you cut into it, thus the increased mold production....I think..
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Embarrassing question, but why does it hurt when shampoo enters the urinary tract?
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Shampoo contains chemicals that are designed to strip away the oils from your hair. As a result, it's somewhat harsh on skin. The skin/tissue inside of your urinary tract is particularly sensitive and thus much more likely to experience problems if such abrasive chemicals come in contact with it. If you read the labels, it'll probably say "for external use only" for this reason.
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Your body interprets the inflammation (swelling) of the tissues as having a full bladder. So you get the signal to go to the bathroom. But because the Urinary tract is inflamed it is hard for anything to travel down it and hurts when it does.
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How do self driving cars interact with traffic lights?
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Self driving cars have cameras that look all around them all the time. Their computers employ visual analysis algorithms that detect what they can see - cars, people, sidewalk, and other obstructions on the road. Traffic lights are incredibly easy to detect - just find a big red/yellow/green ball in front of you.
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Some traffic lights are designed to detect the presence of cars. They use an inductive strip which runs current, and will respond differently if a car is on top of it because the strip will induce current in the car's chassis and body. They can thus detect that a car is present and adjust light timing accordingly. Other lights are "dumb" and just switch based on a preset timer, so you will be stuck at them regardless of traffic flow.
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Is it possible for 0% humidity to ever occur on Earth? How would the human body react?
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The only way to get absolutely 0% humidity is a vacuum. If we got to as close as possible (a few percent), we wouldn't have trouble breathing unless for a long period of time. We wouldn't get dehydrated rapidly, maybe slightly quicker, but our skin is made to help with that. If you inhaled heavily, it would dry your throat a bit, but it would go back when you stopped. You can see this during winter. When it's really cold out, the humidity is very low because the water condenses and falls to the ground. In short: Not possible to get absolutely 0% moisture outside of a lab. The human body would be fine. We wouldn't get dehydrated. It wouldn't hurt to breathe normally.
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The humidity would have to be 100%, meaning that the water vapor is in equilibrium with the puddle of water. The room would also have to be airtight so water vapor couldn't leave the room, and there couldn't be any objects in the room that would absorb water over time. Also, the temperature couldn't increase, as then more water would have to evaporate to maintain equilibrium.
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Does boiling purified water for 5 minutes actually make it more sterile than boiling tap water for 5 minutes?
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Domestic water filters are not (generally) there to sterilise, they are there to remove stuff like chlorine and mineral salts (usually through the use of [activated carbon](_URL_0_) and ion exchange resins). So boiling and filtering perform two separate functions.
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Purified usually means it was run through a filter. Distilled means it was boiled and the vapor collected to remove contaminants. Deionized water has had all of the mineral ions removed. Deionized water is primarily useful for scientific experiments. Both purified and distilled water are fine for drinking and cooking.
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Why do there seem to be so few (well-publicized, at least) archaeological finds from sub-Saharan Africa?
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There are several reasons. The first being that there is less interest among the general populace in it, therefore fewer networks will report it as it doesn't help their ratings. The second being that archaeology is harder to do in Africa, due to remoteness and lack of functioning governance in many parts of the continent can cause problems with how artifacts are handled and whether they can be removed from the country to be studied. Lastly it's harder to get grants to do it the first place, due to lack of support from the donor class who are more interested in european and near eastern cultures. It's not that the cultures deserve less attention, it's that the field doesn't get the political support from research institutions because it doesn't drive more donations.
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It's a political problem. Large parts of sub-Saharan Africa are basically kleptocracies ruled by thieving dictators who only seek to enrich themselves and build prestige.
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What makes things smell?
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Something's smell is just little particles of that thing that got knocked into the air and found their way into your nose. There are receptors in your nose just like the ones on your tongue that react to a particular thing and send an identifying signal to the brain.
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The smell of space has been described in a variety of ways, by many different people. The most common seem to be along the lines of seared steak, hot metal, and welding fumes. Think ozone, sulfur. Gunpowder. Those metallic smells.
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How much Nazi propaganda was aimed at, or designed for, young children? Did it have any lasting effects on them, and a post-war Germany?
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The book distributed through to pre-schoolers was "Trau keinem Fuchs auf grüner Heid und keinem Jud bei seinem Eid" by Theolinde Elvira Bauer. After the war the Germans wrote a lot of moralising pedagocical literature about it's horrendous lasting effects on the human soul but the children themselves seemed to chime in pretty well into the new ideologies.
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FWIW, the Nazis tried this to discover the "original" language of humans. Obviously no reasonable entity would try this for ethical reasons. The speed at which they would develop a language, if they did, is also very important. There have been several cases of feral, non-speaking children who could learn to function in society to various degrees, though could never master language since they didn't learn it at the appropriate stage of development. Another random point (none of which are answering the question, my apologies) is that the human brain is naturally equipped to understand and use speech, though there is no such innate skill in regards to reading. The ability for these children to understand writing systems (much less create their own) would be significantly harder than speech (beyond the use of pictograms, that is).
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The concept of idempotency
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It only does it's thing once, no matter how many times you do it. Like "turning on a flippy light switch". You turn it on once, and the light's on. If you try to turn it on a second time, the light's still on. That's an idempotent operation. Not like pressing the power button on your phone, where the first press turns it on, the 2nd turns it off, and the 3rd turns it on again. That's not idempotent.
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Ideologies are entire systems of beliefs, comprised of many ideas, and supported by one or more philosophies.
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Why does capillary action not violate conservation of energy?
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It works because having the fluid rise up is the lowest energy state. The water molecules prefer to adhere to the walls of the tube and cohere to each other. That is, the formation of intermolecular bonds is energetically favourable, so much so that increasing gravitational potential just to form these bonds is still lower energy overall.
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The same reason why a water treatment plant has drinking fountains. The apparatus to deliver water/blood over a distance is different from what is need to pass it on to the end user. Blood cell zooming through a massive artery don't slow down enough for oxygen to be transfer, nor are artery walls adapted to that purpose. That is what capillaries are for.
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Did Octavian and Julius really have a sexual relationship?
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Octavian was very much in favor of preserving family values, but he wasn't against homosexuality; Romans of his time didn't even have a concept of homosexuality in our sense. Octavian was against *stuprum*, "sexual immorality" - or more specifically, sex acts that degrade Roman citizens. In the Roman way of understanding sexuality, being penetrated is always degrading, unless you're a woman and it's your husband. So Octavian was against adultery, and against Roman men having premarital sex with freeborn Roman women, and against Roman men having sex with freeborn Roman boys or men. But he didn't have any problem with Roman men having sex with male slaves or male foreigners; from the Roman perspective, men being attracted to teenaged boys was the norm. (The best source on this is Craig A. Williams' *Roman Homosexuality*.)
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Not to discourage any further answers, but while you wait you'll pribably enjoy reading this answer by /u/XenophontheAthenian on [What is the source for Julius Caesars supposed love interest with King Nicomedes of Bithynia?](_URL_0_)
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Good first source (book) on Chinese cultural history?
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I normally recommend this anyways, as it's a really fantastic series. [From Yao to Mao: 5000 Years of Chinese History](_URL_0_) is a lecture series by Ken J Hammond. It's extremely accessible, and is quite detailed for such a broad series. He covers a lot of the early formative events and systems, and it'd be a great way for you to "know what you don't know", in a way (that is, figure out what you want to google search and go into in more depth on your own).
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I don't suppose you've come across Peter Gue Zarrow yet? *China in War and Revolution* was a popular textbook in my university's East Asian History department. Unfortunately I don't know any other authors off the top of my head. You may want to start your search with the Nanjing Decade, from 1927-1937. If I remember correctly, the period saw a major focus on urban development, with attempts to open up to Western goods and technologies; the countryside didn't receive nearly as much attention, however. Worth noting is that Chiang attempted a cultural reformation of his own of sorts with his New Life Movement, which was a mixture of Confucian and I believe Christian principles. I've forgotten many of the details, though, and wouldn't dare describe it more without consulting a book first. Hope that helps!
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When we whistle a song, how do we know how to whistle the right notes?
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Some people don't and are bad whistlers. We learn through experience, just like any other instrument.
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adamup27 is correct. You're not tone-deaf, otherwise you wouldn't be able to notice you weren't hitting the right notes. You're simply not as adept at hitting a not exactly when singing as you are when whistling. Practice, practice, practice.
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Explain why damaged organs cannot regenerate. They were made by body, why can't my body repair what it has made, or at least make another?
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The regeneration process is done by the stem cells. They are the ones who change into specific cells based on their environment. The more stem cells the faster your body regenerates. Most animals start out as all stem cells that grows into an embryo. As you get born and grow from a baby to a toddler the ratio of stem cells decreases. You are still able to regenerate smaller damages like cuts but not bigger things. For example small scars can heal in a few years or decades but bigger scars take longer. Amputations does technically grow back but at a rate of millimeters a decade. Some animals are known to have a good ability to regrow amputated limbs but they have a lot more stem cells then humans. This does affect them negatively in other ways.
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I think we still lack the material or coating material that is not rejected by the body. Nowdays you would have to take Immunosuppressive medication and similar stuff to make your body hopefully accept the organ. That reminds me of a documentary about the first time spider silk was synthesized in the lab and one application was for wound recovery and coating of artificial organs as it is antibacterial and had good properties to not provoke reactions from the body. (no expert opinion)
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Unsolvable Math Problems
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Important to note: there are yet unsolved problems, and there are unsolvable problems. The difference is that there are problems that can be solved, but nobody was smart enough yet to prove it. And there are problems that simply CAN'T be solved. You can prove that these problems can't be proved. If you wanna know a little bit more about this subject I recommend two documentaries: The first is called 'Dangerous Knowledge', which is about unsolvable problems, more specifically the Continuum hypothesis. The other one is 'Fermat's Last Theorem', this one is about a very very very hard problem (RabbaJabba explained this one too), and how they solved it. You find both on youtube. EDIT: I mixed up p-np with continuum hypothesis. Sorry...
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Math, in the most abstract sense, is about systems with rules, and exploring the consequences of those rules. [Godel's Incompleteness Theorem](_URL_0_) proves that for a mathematical system of sufficient complexity, there will be statements that are true, but that cannot be proven to be true. This means that mathematics cannot be 'solved', or that you will never be able to prove all statements that are true in any mathematical framework.
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At what scale are things so small that color doesn't apply?
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When they get smaller than about half the wavelengths of visible light. So about 200 nanometers or less
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There's no _single_ thing. It depends on the compound(s), it depends on the state (gas,liquid,solid), on the arrangement of the molecules in the solid (if it's solid). It can even depend on the _size_ of the particles of the substance (gold is yellow, nanoparticles of gold are red). Different colors come about because matter absorbs different types of visual light differently (e.g. if it absorbs blue it looks yellow, because that's the complementary color to blue). If something absorbs all light more or less equally, it's white, grey or black (depending on how much it absorbs). It's quite complicated to predict, actually.
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Why are most humans incapable of running at full speed if hands or arms are restrained
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Arms are used as counterbalance when taking long, rapid strides.
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Their muscles attach to the bones of their arms and legs in such a way as to promote strength. But they have less fine motor control because of this. Humans on the other hand are more dexterous and have fine control at the cost of potential max strength.
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The difference between original and remastered music, and how they go about remastering it
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The original master might be on a medium that degrades, or carries with it inherent noise (like tape or vinyl). Remastering is the process of creating a new master. You take the original master, and create a new version of it on a new medium, often re-mixing, changing balance, and removing noise or other unwanted artifacts from the recording.
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A *master* is the original finished copy of a piece of audio or video. Before the 1980s, all masters were analog. Copying it meant playing it, and each time you played, it would wear out a little. Masters were used a little as possible, you'd make 10 copies, then 10 copies of each of those copies, etc., until you had all that you needed. Between occasional copies and just the physical breakdown over time, the quality of the master would degrade. Remaster means two things. First, you convert the master to digital, which does not wear out. Then you carefully process the digital copy to remove and repair an imperfection, resulting in a better version that will never break down.
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How can an experienced chef tell if food was frozen or microwaved just by tasting it?
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Mainly it's about knowing what a particular food item should taste like, and then comparing. For example, I have these frozen breaded chicken patties. I either microwave them or put them in the oven, and they taste different depending on what I do. More specifically, if I microwave them, they tend to have soggier crusts and be unevenly heated and may be dry/tough in parts. If I bake them, the crust is dryer and tighter on the chicken and it's more evenly heated. So basically, it's just taking experience and then perceiving what you are eating.
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microwaves heat the water molecules inside the food, as opposed to ovens that heat the air which heats the food.
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How do poops and farts work together in the digestive system? Are they lined up in a row or can a fart overtake a poop?
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The poop isn't compacted into a turd until it reaches the end of the digestive system and is ready to exit. It's more of a mush that doesn't completely fill your tubing, and which needs to be actively squeezed through. Imagine some ice cream inside a drinking straw. You can blow air through it while there's still a lot stuck to the sides. To get it out, you need to squish it through. So, the farts do overtake the poops.
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Inside farts. Your intestines have sphinters, just like your anus. Now imagine if your anus acted involuntary. You'd be farting unpredictably and frequently. Your bowels will do their thing no matter what. When there is less substance to pass through its sphincters, there ends up beings more air and gas passing through, mostly the aftermath of already digested foods. It's your inside sphincters passing gas.
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Between distant galaxies is space stretched or created to expand the universe?
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It is, in my opinion, more appropriate to say new space is being added between galaxies. But that light crossing that distance is being stretched. The way I think is apporpriate to look at space-time is that space is the set of all possible measurements you can make with a ruler, and time all possible measures on a clock. So, as the universe gets older, there are more possible measurements to make between two points. More "space" has been added.
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[This is my comment](_URL_1_c5j75rz) from [the last time this was asked.](_URL_1_) tl;dr: - [The universe is infinite](_URL_0_), and so is the stuff in it. Stars and planets and galaxies forever in every direction. - "Expanding" in this case means simply that *distances increase over time*. If I measure the distance between two points at one time, and then again at a later time, the second measurement will be larger *without anything actually moving*. Note that this is counteracted by gravity, and so only happens on a cosmological scale. i.e. galaxies are not coming apart.
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How do those balancing rocks that people stack, work?
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The surface of rocks are not smooth, the key is to locate an area of the rock where the rock your Balanceing fits in on a tripod, that is the rock makes contact with three areas of the other rock. To visualize it, or you index, middle and thumb tips together to make a triangle, this is the foundation, than put your other index finger in the center. After you find a locking point gently move the Balanceing rock around until you can let it stand on its own, this is trial and error. Lastly to stack again, use you finger to push downward on the rock at various points until you can find a spot that can support lots of pressure (should be around center of the contact point) and that's where the next rock will go.
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You can do the same experiment with a jar of rocks. Shaking the jar allows all of the little rocks to find their way down in the spaces between the larger rocks. Keep shaking and pretty soon all of the big rocks will appear to "climb" to the top.
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Why is there always a Japanese Bonus Track on albums?
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In Japan records are very, very expensive because there are many middle-man and strange royalty contracts. Because of that it's often cheaper to bring records from overseas (like Hong Kong) than to buy it domestically. To combat that local publishers make special Japanese-only editions with bonus track(s) to give people incentive to buy locally.
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Because of studio collusion, CDs in Japan are sold for around twice the price they are in, say, the United States. Bands often put exclusive tracks on the Japanese version as a way to encourage Japanese consumers to buy the Japanese version over a cheaper parallel import from overseas. CDs sold in Japan also often contain other extras like mini photo books in the liner, as well as of course translations of the lyrics. It should also be noted that the Japanese market still remains very much physical media-focused, with the majority of music sales still coming from CDs instead of digital downloads.
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Is there any chance that the Indigenous Australians actually 'stole' the land from another race before them?
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No proof has ever been turned up for human habitation of Australia prior to the initial peopling of Sahul (the larger continent of which Australia is part). So; what if? I haven't heard of anyone trying to prove that people were living on Sahul prior to the arrival of the peoples 40,000 years ago who would became Australian aboriginals. The likelihood of it seems small; landscapes and environments change dramatically when humans enter them- this is one of the ways in which human settlement on Sahul is attested- there are no records of dramatic anthropogenic change in the area prior to roughly 40,000 years ago. So; its doubtful anyone can *disprove that there was anyone there before, but its more unlikely that anyone can *prove there was someone there.
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The Indonesians traded with the Aboriginals, and there are some common indonesian Aboriginal words from those tribes in the North. I believe the reason why no one wanted Australia was that they did not see any benefit of it. It's a harsh scrubby land, and the Aboriginals didn't cultivate the land in the normal ways, but used fire.
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How do we know "YHWH" in the Old Testament was pronounced as "Yahweh" and not anything else?
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We don't. The original pronunciation was lost, as the speaking of God's name is (and was historically) widely disapproved of by the Jews. [Here is an excerpt from *The Jewish Religion: A Companion* reprinted at My Jewish Learning, discussing the Tetragrammaton and talking about this very subject in the first few paragraphs](_URL_0_).
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The major reason for this is that many languages contain sounds that don't exist in English, and cannot be represented with the English alphabet. So the typical solution is to decide "these characters mean this sound, and these other characters mean this other sound", even when doing so isn't strictly phonetic to how English is normally pronounced. However, your example is kind of a poor one for this, because "yarmulke" **is** spelled phonetically. In Hebrew, you pronounce the 'r' and 'l' sounds. We just tend to pronounce it wrong in English.
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Why did Turkey not take all of Cyprus?
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Here is a past post on the topic: * [*Why did Turkey invade Cyprus?*](_URL_0_) ^(24 Apr 2014 | 3 comments) ^(/u/tayaravaknin gives a few reasons for Turkey taking only 1/3 of Cyprus, with a longer comment further up providing an overview of the broader Turkish invasion of Cyprus.)
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For Cyprus it may be because they resent the Venetian rule of their island. Their queen, Caterina, abdicated her throne and gave the island to Venice. Venice, in turn, heavily taxed the island and restricted movement in the political hierarchy to only allow Italians to have the upper positions and kept the Cypriots in the lower positions. In 1562 a rebellion rose up against the Venetians and was put down fairly rapidly. The only good they did for the island was try to prepare it against a Turkish invasion and those preparations were lackluster until about 1570 on the eve of invasion when more actions were taken. Even then the island still fell to the Turks who were no better than the Venetians when it came to ruling the island. The only reason why there are so many Turkish descendents and converts is because the Ottomans tried to move people there from Anatolia early on as opposed to the Venetians who didn't send a lot of settlers. For reference, 1982 Footprints in Cyprus by Sir David Hunt
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I have a cup of hot tea. What's the fastest way to cool it: blowing air directly into the cup, or parallel, close to the surface of the liquid?
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Aside from air, the fastest way is to drop a small amount of ice into it. Not only do you get the cooling of taking water and absorbing heat into the ice you also get the [heat of fusion](_URL_1_) as well, as the ice melts. If you make the tea slightly stronger to begin with, the melted ice will bring it down virtually instantly. As for blowing on it. Blowing on the surface will be much better. Those elsewhere here have left out that the hot tea has a high evaporation rate of the water. There you carry off the [heat of vaporization](_URL_0_) as the water evaporates. Carrying much more heat than just the air flow itself. In addition you would want to stir the tea while blowing on the tea. This will make sure the cooled tea is well mixed and that warmer tea from below is brought to the surface.
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Pre-cool a very thick copper teacup, along with a long, thick coiled copper tube, in your refrigerator set to 1 degree Celcius. Affix the kettle's pour spout to the high end of the tube and set your cup under the low end. Slowly pour the tea into the tube at a rate where the tea spends as long as possible in the tube, then falls into the teacup by dribbling along the inside side of the cup. Wearing insulated gloves, rotate the cup every few seconds to maximize the cooling capacity of the metal cup, but do not rotate so vigorously as to introduce heat via friction. You will now have a very cool cup of tea. Drink the tea by dribbling the tea back through the copper tube and into your mouth. Place your mouth as far below end of the tube as you can, possibly by asking your bewildered neighbor for help setting up the coil apparatus on the roof of your house, to allow for extra evaporative cooling of the tea drops before they hit your mouth.
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what is the point of testing nuclear bombs?
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To make sure the bombs work, see what their effective radius of the various types of damage, see how much radioactive fallout there is. Also to make sure other countries know you have a big dick.
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They're simulating weapons to make sure they work so they don't have to physically test them. Those simulations are hard to do, and not always accurate if you don't have enough computing power. Nuclear physics is really complicated.
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Why has there been so little innovation in the field of fireworks the last few decades?
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There's only so far you can go with fireworks before they just aren't fireworks any more. I'm not sure what exactly you're expecting them to do... That said, there *has* been *incredible* innovation in stuff like launching and coordinating firework displays, as well as some innovation in shapes, types and colours. But, again, it's a small colourful explosion, I'm not sure where you think it could go and still be fireworks.
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There is for populated areas that have a love affair with fireworks. A study from Oahu, Hawai'i in 1974 found a 300% increase in particulates after New Years. [Source](_URL_0_) Visibility decreases significantly as well.
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Why does it take so long to take a movie from the theaters and put it on to a DVD or Blu Ray or even digital?
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The issue is one of marketing. If there was a very short gap between the theatrical release and the (cheaper) DVD release, many fewer people would see the film in theaters. It's not like the technical barriers these days present a real challenge to getting the film out onto DVDs.
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Piracy. The longer people have to wait for a movie the more chance illegal downloads will happen...
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Can someone explain how Solid State Drives work and why they're better than Hard Drives?
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Regular hard drives have moving parts. They're almost like a bunch of dinner plates stacked on top of eachother, all spinning at very fast rates. In between the plates, a little arm with a sensor flies back and forth reading bits off of the rapidly spinning plates. This has all been made very reliable over the years, but it's still, at heart, dependent on the *motion* of the plates and that arm. Solid State Drives (SSDs), however, are more like your computer's memory. There are no moving parts. You just use electronics to read the data you want to. This makes them a lot faster.
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A hard drive has two major component subsystems: 1. The platters, along with the mechanism that turns them, read/writes the data, and takes care of all the physical aspects of the device. 2. The controller board, which *interfaces* between the physical/magnetic storage system in item 1 and your computer. Since different computers implement different communications standards (sometimes called bus architecture or interface), hard drives are made with different controller boards. For instance, Seagate may manufacture the same physical drive with both an ATA and SATA controller board. For the sake of simplicity, they'll be called an ATA and SATA *drive*, when in fact, there's no difference in the storage parts themselves, only the computers to which you can connect them. Does that help?
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How different is our vision from the other apes?
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Depends on the ape. Overall, humans and other apes have comparable visual acuity, color sensitivity, and capacity for object recognition, but [here are a few differences](_URL_0_): * Humans possess slightly different ratios of cones (cells that respond to different wavelengths of light and allow us to see color) and are "red-shifted" compared to other apes. * Humans possess a higher rod:cone ratio, meaning they can perceive differences in a wider range of light/dark environments. * Compared to other apes, human visual perception of local visual stimuli is more influenced by global factors. That is, the contexts in which local visual stimuli are seen have greater impact in humans on how those stimuli are perceived. This may be because humans operate in relatively varied contexts and have to make complex decisions based on the global information found in those contexts.
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Humans have less individual genetic diversity than most other species, and all other apes. The reason we can tell different appearances with humans is because we do it all the time and our brains are trained to tell the differences quickly.
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What happened to far flung Roman provinces when the city itself fell?
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Many of the far-flung provinces had become kingdoms in and of themselves by the time that Rome fell to the Ostrogoths. At this point in the history of Rome, many "barbarian" groups had been allowed to settle inside of the borders of the Western Empire. These groups had their own leaders who theoretically paid homage to the Emperor, but that is also malarky, as the Emperors by this point were usually figureheads for other powerful individuals. When Rome fell, those places really just kept on doing what they were doing. It's not like everything was fine right up until Rome fell. The trouble had been brewing for over a century, ever since the Empire was divided in two.
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A big shout-out to /u/iguana_on_a_stick, who has just written a [superb answer on the causes of the 'fall' of Rome](_URL_0_). This is a huge topic and I think that he did a great job summing the various 'schools' of thoughts involved. A quick comparison to the answers in the FAQ would show that this answer is more than double the length of all the existing responses, so thank you so much for writing this. I've thought about doing something like this before, but the prospect of dealing with such a complicated topic is always so daunting! I really look forward to discussing this more with him in the future - I'm very much of a proponent of the idea that Rome never fell, so this should be interesting :)
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Why does laminar flow occur?
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A better question would be to ask why turbulent flow occurs. As you know at low speeds and hence low Reyonlds (ratio of interial to vicous forces) the flow is laminar. As the flowrate increases inertial forces also increase and the viscous forces cannot slow down the fluid to keep the flow in straight lines. You get forces acting off centre giving the flow angular momentum and hence vorticies are created. So to answer your question, for low Re the viscous forces are sufficiently greater than the inertial forces to keep the flow in straight lines.
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Eddy currents. The laminations block the flow of current in that direction and help block the formation of eddy currents which would lead to inefficiency and cook the motor. I’m sure google has some animations to help visualize it
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What causes programs to have "not responding" errors?
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In Windows, there is a concept known as the "event pump". Basically, windows creates a big list of events (mouse has moved, mouse has been clicked, keyboard key has been pressed, etc...), and it expects programs to check in once in a while to collect their events. This is sort of a contract between the OS and the program: "I'll gather stuff for you, and you will swing by and grab it once in a while". If for some reason the program fails to collect events for a while, Windows is not sure what to do. "Does it mean the program is stuck?", "Does it mean the program is just working on a large task?", "Does it mean the program is waiting for data from the hard drive?" Windows cannot tell the difference, so it just throws it's hands up in the air and says: "This program is not collecting its mail, and I can't tell why". Why is it that windows cannot tell the difference? It boils down to a famous problem called the [halting problem](_URL_0_) which we have proven a long time ago is impossible to solve.
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Sounds like an error code. It's basically the computers self diagnosis. An administrator could use it to try to lock down what went wrong.
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Do mosquitoes drink spilled blood, or do they only suck it straight from the animal?
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Female mosquitoes detect food sources through carbon dioxide emissions from our breath. Once they’ve located a food source, they use heat detectors to locate a suitable place to pierce the skin with their sharp proboscis. They then pump the blood up the proboscis and into their gut. [Source](_URL_0_)
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Unlike some other diseases such as malaria, HIV does not spread from the blood mosquitoes drink into the rest of the mosquito's body, it stays in their stomach contents and probably dies there. There is known theoretically a way a mosquito could spread HIV but it is a bit complicated and unlikely. Basically, a mosquito drinks from an HIV-positive person and shortly after lands on an HIV-negative person to bite them; the person swats the mosquito splattering the fresh HIV-positive blood from the mosquito's stomach onto their skin; they then scratch themselves so vigorously that they break the skin which allows the HIV-positive blood to touch their blood. There is not a known case of this happening so far.
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Where are all of the foreign domain names?
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Generally, they're used by people who speak that language, and you presumably are reading English content. If you're making English-language queries on _URL_1_, for instance, you'll be shown results that are in English, which are far more likely to be hosted on English-language domains. If you were to search _URL_0_ for something in Japanese, you'd be a lot more likely to see domain names that are in Japanese.
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Most of the time these sites originate outside of the US, therefore outside their jurisdictional area.
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How can someone be allergic to soy milk and soy sauce, but not soy beans (like edimome)?
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Organic compounds are complicated things. There isn't just one single "soy" thing which causes allergies, there are like fifteen different proteins. And processing the beans changes them. Edamame are cooked with heat. It's probably as simple as that.
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I've only heard of one: _URL_0_ and it's pretty interesting. They stuck a gene from Brazil nuts into soybeans to increase methionine content. Whelp, people allergic to Brazil nuts then experienced sensitivity to the modified soybeans.
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at fast food drive thru places where they have multiple lanes for ordering, how do they know which car is which when they get to pay/collect food?
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Generally, the order in which the orders are placed will be the same as the order the cars pull up to the window. As soon as your order is complete, you'll be pulling forward, and therefore next in line. If two finish at the same time, there is a camera that can identify which car pulled forward first.
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Most pizza places will have multiple drivers, each with their own car. They stagger the deliveries they take, so there's usually at least one at the store to take whatever next delivery pops up. If the managers think that there won't be enough drivers to keep up with the rate of deliveries on a given day, they will just put more drivers on the clock for that day. The radius that a given store will deliver to is decided based on about how long it will take to drive to the farthest edges of that radius. If the radius can't cover a whole town, that's why you'll sometimes see multiple of one chain in a town. The promise time for deliveries is usually no more than 30 minutes, but this will vary from store to store.
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How Doritos and Mtn Dew became the poster child for gaming?
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It wasn't an accident, it was the result of deliberate marketing agreements. As gaming became mainstream the two brands knew that they were generally liked by the gaming demographic so they advertised together.
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how did counterstrike get started? some kids made a mod and gave it to their friends. it got popular and eventually spread through the internet to other people. and valve eventually hired the guys (i believe) so generally, word of mouth, onlinemarketing, friends/family etc.
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If matter ceases to move at absolute zero, is it no longer considered matter?
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Absolute zero does not mean that all matter ceases to move, it only means that all atoms are in their lowest energy state (ground state). They still vibrate and rotate, but they only do so at the energy level of the ground state.
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At a point when everything in the universe is at absolute zero it does NOT mean that everything is standing still. Due to the Heisenberg uncertainty principle, this simply cannot happen. A better way to thjnk of it is that at absolute Zero we reach a point of minimum movement. Particles would be undergoing small oscillations
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Why does your nose start running immediately after eating spicy food?
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because the spices contain capsaicin. Capsaicin binds to your receptors, and literally makes your brain think youre on fire, which sets of all of these alarms, so your nose starts running, you start sweating alot more, you crave something to drink. Just remember, water doesnt work as its polar, while capsaicin is nonpolar. Thats why drinking milk with alot of fat works better, as it is also nonpolar.
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Before I explain sorry for my English but My native language is Japanese ^.^ When you choke on the food your throat is closed to the air and so your body pushes air through the throat in the form of a cough to dislodge? your throat. Your body also has secretions to lubricate your air ways like nose mouth so you can get air. When you push air up in cough, it also pushes air into your tear ducts which males your eyes water. For the spicy food it is a different process but it is because your throat is sensitive and your body reacts to protect your eyes because it considers as veery important in case the spice enters the eyes. Also for example if you are hit on the face in sports especially the nose you might have the eyes to water because of to protect the eyes from danger. Hope this helps!
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I often hear the humans can outrun/outwalk a horse over long distances What was a typical daily/weekly travel range of pre-mechanized cavalry unit vs that of an infantry unit? Is there any work that compares these numbers between different cultures?
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If I could add to this: What about just normal couriers (a single runner vs. a single horseman)? Also, any info on merchant travel times? A man, his wares in a cart, and his oxen/horse, what kind of time would such a person make while traveling. I suspect these questions along with OPs would all be answered by the same person so hoped to throw a little more into the pot. Thanks!
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I made a brief post earlier this year which might have some info you're after, seen [here](_URL_0_). I strongly recommend reading the paper linked in that post, *The Road To Emar*. It'll give you the details of what we know about Mesopotamian travel times and the texts from which we know it. If the paywall is a problem, I can summarize later. For now, I'll note that you typically wouldn't have had a mount to carry you in your travels. Mules and onagers were used as beasts of burden, and horses were used to pull chariots, but no animals were generally fit to be ridden until the adoption of cavalry by the Neo-Assyrian empire, around the beginning of the 1st millennium BCE. So, your rate of travel would generally only exceed walking speed with the help of a boat, which were (and still remain) a common and important method of transportation. Boats would be shallow and small, and often merely consist of a woven-reed raft, especially in the marsh-like southern areas where serviceable wood was a scarcity.
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What is Avogadro's constant and how does making the worlds roundest object make it more precise?
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Avogadros constant is the number of atoms in a defined amount of a substance (in this case 12 g of carbon). It is useful because we cant easilly measure the number of atoms in say a cup of water, but by weighing it we can calculate the number of atoms. However, this definition has no easy way of measuring this number in the first place. We have to use a separate method. One way is to use xrays on a silicon object to measure the size of a silicon atom, and knowing the size and weight of the silicon object we can work out the number. For technical reasons this is most accurately done of a perfect sphere of silicon.
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First off: It's named after Avogadro, but Avogadro didn't actually provide an number. He just proposed the idea that the volume and number of atoms in a gas are proportional, all other things (namely, temperature and pressure) are constant. It was first calculated in 1910 when Robert Millikan, and American Physicist, managed to determine the charge on a single electron; which is doable by reacting very small amounts of things, and looking for the LCD in the charge. Because the charge on a mole of electrons (measurable by arranging a chemical reaction using moles of atoms) was known, it's just a division problem from there. And it wasn't that precise at the time, but has gotten more precise over the years.
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Why is Satan often pictured as sitting in many paintings/drawings?
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If you're referring to the sitting demon with the two fingers raised its not Satan right? Its Baphomet?
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Like some other people have said, most Christian sects and related religions (like Judaism and Islam) are largely against religious art, since they see it as a slippery slope to worshiping idols. The Catholic Church is different because during the middle ages, Western Europe had terribly low literacy rates, so pictures were used as reference material for teaching history and belief to the common people. A depiction of a saint, or a scene from the bible, was full of information and would help viewers learn and remember that information. So while other churches were willing to destroy their icons, the Catholics would have been giving up a valuable teaching tool, and felt it would hurt their followers to get rid of them.
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What is the point of record labels?
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Back when physical records and old media advertising was necessary they provided the capital investment necessary to get an album on store shelves. The band members themselves usually didn't have the time or resources to produce a million copies of a record. In the digital age they're quickly becoming obsolete, a band member can get their work to the masses with the help of one computer savvy friend in one afternoon.
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The concept of a "master" goes back to when vinyl records were the most common form of recorded music to be sold. The common process was to record each artists performance on magnetic tape. You would have the drums, guitars, strings, vocals, etc all recorded on individual tapes. This allowed very good recording of each instrument...with specific microphones. After this was done, the tapes were then mixed down to create a *master tape*. From this master, master mothers were created to press records. For a re-master, the original recordings (those individual tapes) would be remixed... often though much more modern equipment. Noise reduction, EQ, and other processes could be applied...almost always now done digitally. At the end, a new master is created, and then copies of this are made and sold.
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Why are redheads called gingers even though ginger isn't remotely red or orange?
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The flower of the ginger plant is bright red.
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Red heads have a mutation in their MC1R (Melanocortin 1 receptor) that stops it functioning. Normally this receptor is involved in the UV response pathway that causes melanin producing cells to switch from red/lighter pheomelanin to darker eumelanin. As a result redheads cannot tan.
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Why would a president choose to record their conversations? If tapes can be so incriminating, why make them in the first place?
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Nixon did it so he could preserve the historical record. He planned on writing a book after he left office detailing his Presidency. As for the 'incriminating' part, you need to bear in mind that while such tapes can be *prejudicial* they can't really be 'incriminating' in the conventional sense because the President is largely immune to legal repercussions from performing the duties of his office.
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He wanted them as an aid in writing his presidential memoirs, and may have anticipated them (or transcripts of them) becoming part of his presidential papers. He never intended for them to be heard by the public within the lifetimes of anyone being taped.
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What is an API (Application Programming Interface)?
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Lets say Facebook has an API (I know 0% about Facebook or if it has an API, but this will serve as an example). Obviously, Facebook has some code behind it that allows you to post things to your page. This code is used internally by the Facebook website to perform the post. This code is not shared with the outside world. The API may give you a function called PostStoryToWall(). So an API call to post some text to your wall may look like: PostStoryToWall("Hey guys, anyone want to chill today") An API usually allows you to perform actions against an application that someone has already created. The API is created to assist future developers access this application. A cloud storage API may have a function called AddFileToFolder(*name of file*, *folder to place file in*). You may use this function like so: AddFileToFolder("document.txt" , "Some Folder Name")
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There is a wonderful programming language called [processing](_URL_0_) that was developed at MIT specifically for people with zero programming experience to create visual applications. It comes with it's own editor, and has an excellent tutorial. You can make your own simple interactive applications in 10 lines of code, with no importing libraries or anything ugly. In addition, it has a mode specifically for android development, and you can export apps directly to a phone connected by usb. I can't imagine anything easier, and there is a ton of documentation and help videos. It's built on java, so if you get good with it, it's easy to move on to more complicated programming.
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The difference between torrent files and magnet links and their legal implications.
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The short version is that Magnet-links change the the way the BitTorrent is involved in managing and presenting downloads. This affects the legal arguments about whether the server-owner is responsible for whatever is going on. |Service|Narrative| |:--|:--| BitTorrent|Hey, dude, check out all the cool the stuff I've got. Movies, warez, whatever, just click on the category. Magnet-links|Oh, you want something matching `{$HASH}`? Well, I'm can't tell what it is but I'm sure it's perfectly legal. If you wait a moment, Let me innocently help you find other people who are interested in sending or receiving the same thing. Magnet-links are actually older than torrents, dating back from the days of truly distributed P2P networks like Gnutella.
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Torrents store the metadata within files which you download and open up with your BitTorrent client. Magnet links store the metadata within a URI, which your BitTorrent client is set up to handle. You'll notice that you don't have to download a file in your browser when you use magnet links, whereas using torrent files makes you have to download a file.
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If something is harder (Mohs scale) than something else, how could it ever be scratched by the 2nd object?
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A pure substance which is measured at some number X on the Mohs scale should theoretically not be scratchable by something that is lower on the scale. That's how the Mohs scale was created, by comparing what things can scratch what other things. Your clean finger can't scratch glass, unless the glass has a flaw or impurity on it that allows you to swipe something other than your finger across the glass. You *can* use relatively soft things to cut or polish harder things. Blasting them in a stream at very high velocity, for example. Or embedding them in something (like a buffing pad) and moving them at high velocity and/or high applied force. Pure water is not great at causing erosion, but it will still occur. Natural rocks don't tend to be pure substances formed into nice crystals. They contain flaws, fissures, etc. As soon as a bit of rock is dislodged by the momentum of the water, the water now contains an abrasive, and it can more easily dislodge more bits of rock downstream.
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Like ManOfClay says, the glass on the windows is tempered. This increases its strength, but makes it very susceptible to scratches. Why did I post instead of just upvoting him? Because there's this incredible video of [Prince Rupert's Drops](_URL_0_) that shows the amazing difference between general toughness and susceptibility to scratching.
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Why is female circumcision frowned upon, while male circumcision is generally accepted?
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> while male circumcision is generally accepted? About 1 - 2 years ago I saw a documentary where I learnt this is a common practice in the US. It's somehow linked to John Harvey Kellogg (one of the inventors of Kellogg's corn flake) attempts to prevent male masturbation which he believed unhealthy. The only people I would have associated this with before would have been Jewish males who did it for religious reasons. To me this is seriously weird. Literally it's something I'd expect from the most backass of countries where people still live in tribes and so forth. How it managed to become common I can't understand. i.e. You want to cut some skin off your son's junk? No need for him to decide. Answer: Obviously. Of course.
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Scientists don't know exactly why circumcision developed as a cultural practice. The two common theories are: 1. For hygiene. The foreskin is an easy place for germs to collect and frequent baths are not something you can get everyday if you live in the desert. 2. For "Purity". The foreskin is very sensitive and sexual lust is often associated with the primitive and animalistic. By reducing your sexual lust, you become less like an animal and more like a human who is above his primitive urges (according to some religious teachings).
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Pointers and references in C++ and how they work?
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To put it simply, if your computer is like a city and houses are data, then a pointer is an just an address to a house How it can be useful is when instead of passing (copying) possibly huge chunks of data between functions, you just pass the address where this data is stored
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Instead of holding the literal data, a pointer is a variable that "points to" where the data is stored. Under the hood, passing by reference is implemented with pointers. In lower level languages like C and C++ pointers are much more significant, where they are literally a memory address. There isn't any guarantee that something exists at a given address, which is why pointers are dangerous - they can point to something that isn't there. In general the only time you can be sure about a pointer is if it is null, usually a value of 0 (but not always). The null pointer is guaranteed to point to nothing, so when you're done with a pointer you reset it to the null value and if later code tries to access data pointed to by a null pointer you get an exception and/or a program crash. If you try and access data on an invalid pointer (address isn't null, but nothing is at the address) you're entering undefined behavior.
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How long would one survive, if water was to be replaced by beer?
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I assume you mean, say the world ends, and all that is left is beer because it's the only way to disinfect the water? The answer seems to be a very long time. _URL_0_ Basically when water was bad you could drink beer to keep hydrated, as long as the alcohol content was not high enough to cause dehydration (the lower the better, alcohol blocks your anti-diuretic hormone, this can lead to dehydration), you would be more or less okay. (Though you might burn out you your liver by the age of 40-60, that is a lot of toxin to filter.)
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Not to deter discussion of the main question, but the idea that beer replaced water for safety is a myth that u/idjet discussed in [this comment](_URL_0_).
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Why does garbage bunch up in the ocean?
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Because of the rotating Earth's [Coriolis effect](_URL_0_), the surface of the ocean responds to wind in a funny way: it moves *sideways* to the wind direction: to the right of the wind in the northern hemisphere, to the left in the southern hemisphere. This is known as "[Ekman flow](_URL_1_)". In the tropics, the winds are tradewinds from east to west, so they cause Ekman flow in the ocean away from the equator. In the middle latitudes (40 degrees north or south), the wind blows from west to east, Ekman-pushing water toward the equator. As a result, in the "subtropics" region between 15 and 35 degrees in both hemispheres, the water gets pushed together like a trash compactor. As it converges, the water has nowhere to go but down. It descends, but the floating trash can't sink, so it gets trapped at the surface in the subtropics. In other parts of the ocean, the winds push water in a divergent pattern: those areas don't accumulate garbage.
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Because there isn't actually a garbage patch. Well, there is a lot of trash there, but most of it is composed of microscopic plastic particles produced when plastics break down. That patch of the ocean looks like any other patch of ocean. All those pictures of see of the Great Pacific Garbage Patch are not real, they are photos of Manilla Harbor.
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Why is the "Enola Gay" B-29 (dropped the atomic bomb on Nagasaki) a well known name among the American public, but the "Bockscar" B-29 (dropped the atomic bomb on Hiroshima) not?
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I think you have them switched in the title, Enola Gay dropped the Hiroshima bomb, while Bockscar was responsible for Nagasaki. There's a certain value in being "the first" to do something, which would result in Enola Gay being remembered for being the first to drop at atomic bomb, much as more people could tell you Neil Armstrong's name, compared to Buzz Aldrin's.
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They wrote their names, mostly. [One photo](_URL_1_) (guy writing in front is Norman Ramsey, future Nobel Prize winner and part of the assembly team), [another](_URL_0_), [another](_URL_2_) ("A Second Kiss for Hirohito! W.R. Purnell, Rear Admiral, US Navy"). Similar things were done to the Hiroshima bomb but most were painted over before it was dropped. Generally it was the assembly team, but by the time of the Nagasaki bomb the import of these bombs was more generally known on the island so you get things like rear admirals signing their names.
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How is a person kept alive during a heart transplant, where the old heart is out, but the new heart isn’t in yet?
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Your heart is just a pump that moves blood around your body. Surgeons have a machine with a pump called a "Heart Lung Bypass" that they install to keep blood moving around while they work.
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100 years ago, if you had a heart attack, you died. We've since created a difribulator that can revive someone if you catch the cardiac arrest within a few minutes. So now, if you "die" from a heart attack, you're not really dead until after a few minutes. The idea of cryogenic preservation is that you use chemicals to preserve your body at the time of death hoping that people will figure out how to deal with what killed you. In the future, maybe we'll find a way to revive someone from cardiac arrest after 40 minutes, or 100 years. If your body was preserved and you had died of cariac arrest 100 years ago, they could revive you! Wait but Why blog has a really good post about this. _URL_0_
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Japan did horrible things to China, and we were at war with them during WW2. How is it flipped?
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It's been seventy-five years since world war two. Pearl Harbour - when Japan attacked the US - occurred in 1941. That's a whole lot of water that's flowed under the bridge, and more than plenty of time for the leadership and political philosophy (where China moved over to Communism) of both countries to change substantially. The US being diametrically opposed to Communism had a lot to do with that shifting allegiance, as did China's somewhat aggressive expansionist policies. Plus, during that same war, the US was allied with Russia to take on the European theater, so the country played nice with Stalin even though only 20 years later the "cold war" where the two were mortal enemies was in full swing. War creates allies out of necessity, not out of preference. People weren't exactly thrilled to be in bed with the Chinese or the Russians back then, but it happened, and that little affair didn't last long.
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Partly because Japan was already going in that direction before the war. In the mid 19th Century, US gunboats showed Japan how backward they were, which lead to a massive modernization and westernization movement. One of the things other world powers had that Japan did not were colonies, so Japan made some out of Korea and Manchuria. Britain and France weren't crazy about this and felt Japan was a threat to their colonies in the region, and imposed an embargo. That was the primary reason for Japan's participation in World War II. Japan had already been pushing hard to become a Western-style world power, and the post-war reconstruction continued to build on this momentum. > why didn't US do the same for other countries? The Marshall Plan spent over $100 billion in today's dollars to rebuild European countries hurt by the war, with most of it going to the UK, France, West Germany, and Italy.
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What would be the best possible thing to do when your phone gets completely submerged in water, and why?
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1. Take out the battery. 2. Bury the phone in a bowl of rice (uncooked, obviously) overnight. Removing the battery reduces the probability of something shorting out because of the water. The rice will absorb moisture from the phone, and dry it out much more quickly and thoroughly than air-drying. No guarantees, but your warranty is now void now because of moisture damage, so it's worth a try.
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Any holes, like the charging port and headphone port are sealed so water cannot get into the body of the phone. The seals are fairly thin which is why they are only good to about 5 meters, to much pressure will allow water to seep through.
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Why is your throat so much more sore in the morning than any other time when you have a cold?
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Because you've been lying down and not swallowing, the extra thick mucus your nose is producing during your cold has been dripping down your throat all night and irritating the crap out of it. During the day you swallow, drink, and eat which helps clear the mucus out. You're probably also blowing your nose instead of just letting it drip down your throat.
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It's not the air that is causing pain. When you have a sore throat, for example, your body increases blood flow to the throat to help fight off infection and repair damage. This increased blood flow, unfortunately, leads to swelling which puts increased strain on the nerves in your throat, often causing pain or discomfort. When you cough, your throat muscles contract which puts even more strain on those nerves, which leads to more pain.
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Why does flow separation reduce lift?
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Its because the separation dramatically reduces the flow turning effect of the wing. Known as a wing stall. While pressure is somewhat involved its not the primary driver of lift, flow turning is the main driver and when this drops dramatically you get a stall. Find a detailed explanation here including description of boundary layer, flow turning and stall point and how its tested for: _URL_0_
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If you play around with NASA's [FOILSIM](_URL_1_), you will notice that if you drag the angle up, eventually you will get [significant flow separation](_URL_2_) along the top portion of the foil resulting in a [stall](_URL_4_). Separated flow does not contribute to lift, while attached flow does. When playing with the slider, you will see the pressure graph (bottom right of the applet) along the top of the airfoil suddenly jump to zero. Where-as before stall, the top portion contributed to lift almost along its entire length, once stall begins to occur, separated flow dominates, and most of the upper length of the foil no longer contribute to lift. As for computation, it is normally done using a [Computational Fluid Dynamics (CFD)](_URL_0_) software. [The calculations are far too complex to solve discreetly,](_URL_3_) so we rely upon the numerical methods of CFD which are nothing more than an educated prediction of reality.
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Holy Roman Empress Maria Theresa had 11 daughters and they were all named Maria Something. Was there a specific reason for this, or was this a bit of vanity on Maria Theresa's part?
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It was a Habsburg tradition, and had been since the 17th century, so it wasn't Maria Theresa's idea. It was also to show the family's and Austria's special devotion to the Virgin Mary, so you're doubly right. source: Marie Antoinette: The Journey, by Antoina Fraser
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I'd think it's because 99% of sons keep the same first and last name their whole lives. Then you can have Bill Jones, Bill Jones Jr, Bill Jones the Third, from birth onward and the name sticks. Whereas women are much more likely to change their names. Mary Smith's daughter is Mary Jenkins, her daughter is Mary Franklin, so it'd make no sense to say "Mary Jenkins Jr" when there is no Mary Jenkins Sr. Sure, daughters originally share the same last name as mom but usually not after marriage.
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Is it true that Genghis Khan lowered the global temperature? And if so, how much was it estimated to have dropped?
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No. He was an impressive figure, but I think Milankovitch Cycles are beyond even him. This is a pretty classic case of correlation not equaling causation. His rise was towards the tail end of the Medieval War Period, and some have posited that the aggression of central Asian nomadic groups during that period was as a result of this. So basically, blaming Genghis Khan on the end of the Medieval Warm Period is a bit like blaming house fires on firemen.
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A follow up a question: was Genghis Khan literate? How much education did he receive?
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Is it possible that instead of the universe expanding, the matter inside it is shrinking?
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No not really. All of the forces that govern matter are distance dependent, so matter can't really shrink. Furthermore not *all* of space is evenly expanding. There are pockets of the universe where matter dominates and space doesn't expand, these being clusters of galaxies and the stuff within those clusters.
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I am a cosmologist and this thought has crossed my mind before and I have discussed it with my colleagues. And I can't give you a good reason why this would be impossible. However, it seems less likely, because there is no known mechanism that could even come close to causing something like this. Whereas we know that the contents of the universe cause it to expand or contract, so it is just a simple explanation that it's the space itself that is expanding. And by Occam's razor, we follow this explanation until we find a problem with it.
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If space dust falls to the earth constantly, how has gravity been affected by this throughout earths history?
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Ok, I'm just back-of-the-enveloping this one. The internet says that 40,000 tons of space dust fall onto the earth each year. _URL_0_ Multiply that by the age of the earth, 4.5 billion years, you get about 2\*10^14 tons. The current mass of the earth is about 6\*10^21 tons. That means about 0.000003% of earth is space dust. The amount is probably a bit higher since there would have been more space dust early on, but I doubt it's had any effect at all in the 3 billion years or so.
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The Earth's mass decreases by around 46000 tonnes per year. The Earth sweeps up about 50000 tonnes of space dust each year. But this gain is more than offset by atmospheric loss. Roughly 95000 tonnes of hydrogen and 1500 tonnes of helium escape Earth's atmosphere annually.
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Why are there no major cities on the Susquehanna River?
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As European explorers quickly discovered, the Susquehanna is perhaps the world’s longest non-navigable river. Large rocks and shoals begin to appear only a few miles in from the Chesapeake Bay. At high tide, ships could get as far as Port Deposit, but no further. A 1588 Spanish expedition sent from St. Augustine in search of the English colony at Roanoke found the river, but named it San Juan de las Peñas (St. John of the Rocks). In 1608, what we know as Smith’s Falls stopped any further exploration by English Capt. John Smith. Along the East Coast, cities typically prospered at the “fall line,” which was both the limit of upstream navigation and the location of water power that could drive mills or other industry. Havre de Grace and Perryville, Maryland, were indeed both important small industrial cities of the 19th century, but always stood in the shadow of nearby Baltimore, Wilmington, and Philadelphia, which had superior harbors and water power resources.
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Cities don't magically form just because of being at the water's edge. They form where there's a particular defensive or transportation advantage. Considering Montréal, for instance, the city arises where cargoes sailing upriver have to be portaged around the Lachine Rapids, which also happens to be a place where there's a drop in the river, meaning water power for mills. Any place where cargoes must be transferred from one mode of transport to another is a good place to put mills and factories that add value to those cargoes. As for Lake Champlain, Burlington, Port Henry, and Plattsburgh were modest ports in the 18th and early 19th century, but their tributary territories were not strong exporters of valuable raw materials, so the coming of the Erie Canal and later the railroads prompted greater growth in other, better-connected cities of the region, such as Montréal, Albany, Buffalo, and Toronto.
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Did Native Americans have any interaction with dinosaur fossils?
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Speaking of my own region, I can say that they did have interaction with both fossils and with megafauna. In the Nuxalk language fossils are called smalhh meaning that they are things that have solidified or become legendary in their permanence as a part of stories. Largely fossils in the region are of sea life and are ascribed to a flood and specific fossils can even have stories about them or did. Megafauna are referenced in that just going off the top of my head there are Nuxalk words for giant animals with long noses, for giant bears said to be the ancestors of grizzlies and another animal also much larger than a grizzly like a dog. I know of no stories of dinosaurs although there are a lot of references to giant monsters.
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I always thought it was because dinosaur bones were unearthed all over the globe _URL_0_
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What is a boson and why is it sometimes referred to as the God particle?
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[God particle](_URL_0_): Originally Lederman wanted to call it the goddamn particle, but his editor wouldn't let him. Most physicists *hate* the term god particle. It's meaningless and doesn't reflect the physics. adamsolomon's answer addresses the rest of your question.
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Higg's boson is believed to be the particle that imparts mass on a particle. All massless particles that we have observed all travel at the speed of light (photons) since resistance to acceleration is the definition of mass. Scientifically, for now, it is impossible to reach the speed of light if the object moving has mass.
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How are scientists able to make predictions about the compositions of extraterrestrial planetary cores?
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Computer models, basically. We can determine the surface composition by direct observation. We have some idea about how planets form, and we can see if we can predict a planet that has a surface like the one we see. You expect some stratification (heavier elements in lower layers) for instance.
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Look [here](_URL_0_) at NASA's Hubblesite page *Hubble Views Galactic Core in Unprecedented New Detail*.
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Overdosage of acetaminophen (Tylenol) is known to cause liver damage. Does regular dosage cause a little bit of liver damage?
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No. The liver damage only occurs when the normal metabolic pathways for acetaminophen are overloaded or somehow damaged. The drug can be cleared by several mechanisms, but one of them produces a reactive intermediate that can cause liver damage. That species, though, is normally inactivated with a molecule called glutathione, a pathway that quite a few substances go through. But if your glutathione is depleted (by, say, heavy drinking or too much acetaminophen already having come along), then the toxic intermediate gets produced with nothing to stop it. Here's a diagram: _URL_0_
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It is generally drug specific. However, it is likely that this person may be above the baseline for liver damage from other drugs given that they had one in the first place. How much? It depends on the substance in question and how the liver was damaged in the first place (sensitivity VS overdose). Keep in mind, however, after an overdose or a drug reaction, there may only be so much of your liver left. The continued use of any substance that strains the liver may deplete the remaining hepatocytes. So it may not be that you are at a substantially higher risk of another reaction, but doctors might want to be particularly gentle with your liver since it may not have as many cells left.
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Why do "assume" and "assure" have different pronunciations?
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[Assume](_URL_1_) comes from old english, and [assure](_URL_0_) comes from french. I know words derived from french often have different spellings/pronunciations than I would expect. Are there any etymologists in the house who can add more?
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Because [it comes from the Latin word *pronuntiatio*](_URL_0_). The question is therefore why the corresponding verb is 'pronounce' and not 'pronunce', and that is less obvious from [that word's etymology](_URL_1_).
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Was Jesus a Roman citizen?
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While /u/RingGiver is correct that Roman citizens were not normally crucified, there were incidents where this didn't hold up. More directly, Jesus simply had no claim to citizenship. He was born under Herod the Great's rule of Judea as a client kingdom, and there is simply no grounds on which he would hold Roman citizenship.
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This was touched on a little in [a previous discussion on proving Roman citizenship](_URL_0_?). The AutoMod reminds me to mention u/LegalAction and u/mythoplokos in that thread.
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