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why submarines use nuclear power, but this isnt more commonly used on land?
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Submarines benefit from not needing to refuel for long periods. This isn't nearly as important for land vehicles, especially since a land vehicle can stop anywhere, turn off, and consume no power whatsoever. A submarine can't do that. Also, designing an extremely heavy, large vehicle is much easier on water. Few land vehicles are large enough to actually have a nuclear powered engine.
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What is a Deja Vu?
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'Yossarian shook his head and explained that déjà vu was just a momentary infinitesimal lag in the operation of two coactive sensory nerve centers that commonly functioned simultaneously.' - Joseph Heller, *Catch - 22*
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Why do we sing in the shower ?
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The environment of the average bathroom has all the sound you make bounce right back at you, which for recording isn't ideal but for acoustically singing to yourself can be atmospherically pleasing, so we enjoy hearing our own acoustics in there basically
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if the Japaneese knew about the nuclear bombs before the US dropped them on Hiroshima and Nagasaki, why didn't they surrender sooner?
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The Japanese didn't know about the nuclear bombs, not really. They knew about the theoretical possibility and that the US was working towards it. But until the bombs were dropped, Japan had no idea exactly what the US had. Hell, the US didn't really know it, either. To look at it another way, what is more likely, you enemy has a bomb thousands of times more powerful than any before, or that it is some sort of a trick?", 'As important as the nuclear bombings were, many have credited the Russian declaration of war with causing Japanese surrender. Japan was actively trying to agree a conditional surrender with the allies via Russia and thought it was making progress, then one day their diplomat turned up and instead of continuing negotiations, Russia just declared war.
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how does a fan cool down the air in a room
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> Every time I feel hot in my room I stand in front of my fan to cool me down, but I don't know how it cools that air down. It doesn't cool the air down, **you are heating the air up!** The air right next to your skin is being heated by your body so if you push it away and replaced it with room-temperature air it seems cooler.
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What is "mental exhaustion"?
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When you use your brain, it gets tired faster. When you use your body, it gets tired faster. If you use your **brain** a lot more than your body, you have **mental exhaustion** when your body is perfectly fine to keep moving. If you use your **body** a lot more than your brain, you have **physical exhaustion** when your brain is perfectly fine to keep thinking. The actual process is pretty **complicated** if you go deeper. You have ATP exhaustion , stress hormones, actual damage to your muscles, forming new memories, willpower running out , and so forth. But generally speaking, you can overcome brain exhaustion if you like what you're doing, are having fun, and drain yourself often with difficult tasks. This makes the analogy to worn out muscles very useful.
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Why do you need an "escape velocity" to leave earth's gravity? Since gravity is a force, shouldn't it be countered by an "escape force" and not velocity?
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You aren't trying to stop gravity from working, you're just trying to reach a position where it has much less effect on you. The farther away you are from the source, the smaller the effect, but with a source the size of the Earth, you have to go very fast to get that far away before gravity pulls you back towards it.Gravity weakens the further you get away from the source of gravity. Escape velocity is the speed that you 'd need to go so that your velocity is always slowed down exactly as much as the force of gravity is weakened over the same distance, so you don't need any extra force to "escape" from the gravitational influence of the body in question.
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if gravity is gets weaker the further away you are from a large mass, why can't rockets leave the earth by just flying at a low constant speed?
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Let's consider Earth's gravity as a hill and a rocket as a kid on a skateboard trying to go up the hill. If the kid just pushes once while heading towards the hill, he'll probably fall back down. If he pushes as hard as he can and then tries to coast up the hill, he'll get *closer*, but probably won't get all the way up. Now, imagine that kid's friend ties a rope to their car and the kid on the skateboard holds on as the car drives towards the hill. The car builds up speed, and once it reaches the hill, the car stops, the kid lets go, and drifts up the hill. If the car went faster than the hill's 'escape velocity', then the boy *should* reach the top of the hill . Gravity can be seen as a hill, or mountain, because it's all about stored potential energy. As you go up, you're fighting AGAINST potential energy, and that requires increasing your own kinetic energy which is most easily accomplished by increasing your speed. A great image that visualizes this is by xkcd: [Gravity Wells]", 'Preface: "Escape velocity" defines the *initial* velocity an entity needs to get infinitely far away from a planet . Gravity will do work on the entity and slow it down during this journey. At the entity approaches an infinite distance away, it's velocity will approach zero. Now, assuming you are comfortable with that: > shouldn't you be able to just fly straight up into space at a low, constant speed? Yes, you can. It's extremely inefficient though. Consider the energy required to hover above the ground versus the energy required to just stand on the ground. The former requires helicopter-levels of fuel consumption while the latter requires essentially nothing. The solution is to get out of the deep part of the gravity well as fast as possible, so you don't waste energy hovering.
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Why do we need to cook our meat before we eat it but wild animals are fine eating it raw?
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We don't need to cook our food before eating it. We can digest raw meat of all types just fine. Cooking will kill parasites and make it easier to digest though, which is why we usually do so.
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Theoretically why can't objects go faster than the speed of light?
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So, theoretically, nothing can go faster than the speed of light. It just happens that light goes as fast as possible, so it moves at that upper limit of speed. Why that is the absolute speed limit of the universe is a deeper question. However, as other have said, Newton's second law is wrong, but usually you don't find yourself in situations where that matters.
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Why are most Western Languages written using a common alphabet but more Eastern/African alphabets written using different sets of symbols?
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Europe used to have a bunch of different writing systems and the Latin script and its modified descendants eventually replaced them not because of the Roman empire but rather because of the spread of Christianity. Romance, Germanic, Western Slavic, and some others all eventually adopted the Latin script because of Christianity's influence. Keep in mind that Latin and Cyrillic were both influenced by the Greek alphabet. Global reach of the Latin script developed because of colonialism where the Spanish, British, French, etc brought the scripts with them so even a majority of Africa uses the Latin alphabet. Arabic scripts developed during the spread of Islam, so in Northern Europe, throughout the Middle East and all the way to Pakistan. Countries under the Soviet sphere of influence started using Cyrillic and dropped their Arabic scripts. In Turkey, Atatürk replaced the Ottoman empire's use of Arabic with a modified Latin script. You might say recent adoption of Latin script is an answer to globalization and movement away from old imperial influences. If you look at Central Asia, Kazakhstan is slowly adopting a Latin script, Uzbekistan and Turkmenistan already did. As for East Asia, Chinese has great influence for a long time so Korean and Japanese used Chinese writing for their languages. Modern Japanese writing systems developed over time but still include a significant amount of Chinese characters. Korean only recently adopted Hangul despite its invention centuries ago, but they also integrate Chinese characters. Vietnamese also wrote with Chinese characters but the French implemented a modified Latin alphabet to write in Vietnamese. As for other writing systems in Asia, they developed a long time ago out of the Brahmic scripts . This includes writing systems across the Indian subcontinent, Southeast Asia, and its neighboring islands. So Thai, Khmer, Devanagari, they all have the same root writing system.
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How can the universe be both "infinite" and "expanding"?
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The universe *may* be infinite, but it also may not be. At this point we're reasonably certain it's infinite. If it is, then what is happening is not the universe expanding, but rather, the space between objects in the universe is growing larger and larger over time. The whole universe will always be infinite regardless of what the scale of space is, and this scale can reach mind-mindbogglingly huge levels and still always have plenty of room left to grow into.Someone else mentioned a balloon, but the way I could understand is slightly different than what they mentioned. If you blow up a balloon, the surface area has no boundaries - there is are no edges, as you would have if you drew a flat square - so in a way the surface of the balloon is infinite - you could trace path around the balloon over and over and never come to and end point. But it can also expand, as you blow up the balloon more, not only does the volume increase but the surface of the balloon increases as well. So it is infinite and expandingIt hasnt been proven that the universe is infinite, it is the most popular theory but still only a theory
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Why does Pi have infinite digits?
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Take a _URL_1_ has a radius,which is the distance between the center of the circle and the line of the figure itself.There is a relationship between them,right?The bigger the radius,the bigger the length of the line which creates the circle,and vice versa.Now we want to find out what is this relationship between the two-we divide the circumference,the length of the circle,by its radius.and we find out that its 2*pi.As the two are connected,its right for every circle,and this division is not representable in any other way.If you'll take 1/3 you can represent it as 0.33333 or 0. as there is a rule for the digits after the decimal.There is no such rule for pi. The rule is its half of the division of circumference of a circle by its radius.Hope I didn't mess it up too much.
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Why are the 7 continents when Europe and Asia are basically the same land mass?
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> Why are the 7 continents when Europe and Asia are basically the same land mass? Firstly, you have assumed there are 7 continents, but that is only one model. [Different models propose anything from 4 to 7 continents]. Secondly, a continent is not defined by whether or not it is the same landmass. Europe and Asia being connected by land has no bearing on it being two continents, just like two countries could be separated by sea but still be on the same continent. > You can say North and South America because there's a narrow stretch of land connecting the two. Most models have America as one continent, with of course a north and south part, as all continents have.Check out any [plate tectonics] map, there is no Europe or Asia, only Eurasia.
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What is the benefit to a company to enact a policy that prohibits promotion of employees from within?
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A lot of it depends on the position that is open for those internal candidates to apply for. In some cases, institutional or company knowledge will have just as much impact on potential success as education or prior experience in the higher level position. In other cases, that institutional knowledge may not make up for a lack of experience. So let's say I have 2 candidates for a senior job, Person A - has worked for the company for a few years and knows the ins and outs of internal politics, but has never senior level or in charge before Person B - external candidate who has prior senior level experience If it would take more time to train A to do the job than it would take B to learn the lay of the land, than from a business perspective, you'd want to hire externally. If however, person A could do a serviceable job while learning the exact job skills for the job, and you estimate that they would be able to fully handle the responsibilities more quickly than B, then you can promote from within. The issue is that in a lot of places, it's easier to hire someone with experience and let them learn the lay of the land than to train someone from within. So it's usually not a hard rule to hire externally. Another issue that crops up is that because you already work for a company, they already know all of your flaws. An external candidate can often mask their flaws with good interview preparation, making them appear to be a better fit for the position, even when they are not.
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What would happen if we detonated an atomic bomb in the eye of a hurricane?
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A hurricane gets its energy from warm ocean water, and in the process of water vapor condensing into rain droplets. The heat released during condensation serves to continue to warm the surrounding air, which causes more seawater to evaporate, condense, and continue the cycle. A fully developed hurricane releases 50 or more terawatts of heat energy at any given moment, only about 1 percent of which is converted into wind. The heat release is equivalent to a 10-megaton nuclear bomb exploding every 20 minutes. The entire human race in 2011 used about a third of the energy present in an average hurricane. So bombing a hurricane might be about as effective as trying to stop a speeding Buick with a feather. It will make the hurricane worse because:1. There's the possibility that bombing the hurricane, if it had any effect at all, would just add to the storm's heat supply, making it even stronger. 2. You're creating a radioactive hurricane.
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When planets are visible from earth, why do they appear as stars to us on the surface of earth?
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Well, they do appear a *bit* different. For example, planets don't twinkle. Other than that, there's not much else which you can discern with your plain eye, so it makes sense for planets to look the same as stars.
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How do we know numbers like Pi are infinite rather than just incredibly long?
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Thee simple answer is that we have an incredibly complicated proof that requires more math than any average person would posses that tell us so. I think it a good question though. If a number didn't start repeating digits til the trillionth digit how would we know? The answer is almost always complicated math.
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Why is heroin and meth so addicting?
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It alters the pleasure centers in your brain. Over time your body builds a tolerance so you'd need more of it or do it more often to get the same high.
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why does the existence of wormholes automatically make time travel possible?
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Not an expert, but I think it has to do with the amount of distance you would travel in a short amount of time. If you travel through a wormhole to a very distant place, you would be traveling from point A to point B way faster than the speed of light. Time wouldn't be able to keep with the that and you would be traveling to point B in the past. Again, I'm not claiming to be an expert, and all of this stuff is theoretical
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How can photons actually be massless?
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The are massless in that they don't have a rest mass . But they have a relativistic mass. The famous E=mc^2 is true if the particle are at rest If it moves it has a momentum and the equation is:E^2 =^2 + ^2 The momentum of a photon is p=h/λ where h is Planck's constant and λ is the wavelengthSo it has a relativistic mass ant it can be calculated as in the link_URL_1_ and is m=h/ Since a massless particle don have a rest mass they cant be still. And it is even the case that they allways has to travel at the speed of light. One other massless particle is known to exist the Gluon. The Graviton is also a massless particle but it is unconfirmed
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Why does a planet that is very close to its star (or a moon to its planet) often becomes tidally locked ?
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The Earth is 7900 miles across and the moon is 238900 miles away. For the earth to rotate, a spot on the equator has to move 7900 miles further away from the moon. This takes energy to do, so the Moon's presence near earth means that it's always trying to slow down the half of the Earth that's rotating away from it and speed up the half that's getting closer. This slightly deforms earth, bleeding off rotational energy. Earth bled off enough of the Moon's energy to freeze it in place, the moon isn't big enough to return the favor.
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How do you play Dungeons and Dragons
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Think of it as an interactive story told by the DM rather than a game. You build a character, you're responsible for that character and its story in the story world of the DM.
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What IS Autism??
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Here's some food for thought. The brain is not simply a computer in some respects. The way in which memories and emotions and skills develop is due in part to where in the brain that particular memory or whatever it is is located. Have you ever wondered why perfume and aftershave are so popular? It's because emotional centres of the brain use to be used for the sense of smell before it evolved to favour emotion. As a relic of that time, our sense of smell has a strong influence on emotion. Similarly, people with a foot fetish are likely to have unusual neuron patterns as neurons involved with sexual activity are next to those that control the foot; people with foot fetishes appear to have some wires crossed. for people with autism, they use different parts of the brain to accomplish the same goals, however this manifests as the behaviours of autism. Something highly complicated such as social activity and facial interpretation is subsequently relegated to a part of the brain that isn't cut out for that sort of work. Some children even recover once the brain figures out where to put what function where.
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How binary code works?
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It's the simplest form of code, using 1s and 0s to turn a switch on or off. Every computer uses binary at base level.
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why is the speed of light the universal speed limit, and not just the fastest thing we've been able to observe?
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Because of math. Einstein's equations show that your mass increases as you go faster. At the speed of light your mass would be infinite . Since there's nothing more than infinity then that has to be the limit. How do you increase your mass beyond infinity? You can't.
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When something surpasses the speed of sound why does it create a sonic boom, and would it be possible for an object to avoid creating a sonic boom?
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Imagine driving your car at the speed of light and turning on the headlights. What happens? The light can't go any faster, so it all balls up on the headlights. Sound does the same thing. It can't travel through air faster than the speed of sound, so if you're making noise at the speed of sound, it all bunches together. This means that as it travels out you're getting a whole lot of these bunched up sound waves all at once.
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How does the higher education system in the US work?
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College of Business Administration", etc. Community College: A smaller College that offers fewer total classes, and generally only offers Associate Degrees and possibly one or two Bachelor's degrees. These are primarily used by working adults to get additional education, and by people who were not academically gifted enough to get scholarships at bigger Universities to get basic courses completed more cheaply and to get their grades up for application to University.A community college is a 2 year school, that's either a lower end degree or a stepping stone to a 4-year degree from a college or university. The difference between a college and university is that a university include graduate programs and/or professional schools , while a college only offers undergraduate degrees . Often, the undergraduate part of a university will be called a College, so an undergrad attending Harvard University is enrolled in Harvard College, while somebody attending law school would be enrolled in Harvard Law School think if it like a corporation with divisions. Majors and minors are your area of study. Typically one has to take a broad range of courses in the first couple years called distribution requirements this is to ensure everybody takes some math, some science, some social science, some writing intensive courses, and so on. Then you declare a major and focus on that topic so somebody wanting to go to law school might get a degree in political science. Or a future chemist would major in chemistry. A minor is a secondary concentration with fewer requirements. Say a major requires 15 courses in that subject, a minor might require 8. Sometimes they can overlap . Other times it might be that the major is a career path while minor is other area of interest, like music. Or simply another area of interest.
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Why is internet Explorer hated so much
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Recently, Internet Explorer's been a bit decent again. However, old versions of it were infamous for being very slow, especially compared to alternatives like Chrome and Firefox, and for breaking many websites.IE was notorious for accepting badly formed HTML, and allowing ActiveX controls to run, both of which were major security lapses.The other answers are all good and true, but the main reason IE was such a mess was that Microsoft intermingled the code with the rest of Windows. They did this to kill Netscape because they wanted Windows and IE to be inseparable but many people at the time told them that doing so was a very bad idea because it meant any security issues with IE would affect the whole OS. MS did this simply to be anticompetitive and it worked because it pretty much killed all other browsers for quite some time but the downside for users was that IE created a storm of security issues. As MS mingled the code more, they killed off the other versions of IE that ran on Mac and Solaris so IE became part of the whole Windows monoculture and customers suffered a great deal as a result. The IE hate is more of a symptom of MS' leveraging IE and Windows to gain more control and a side effect of that was they stopped innovating once they won and as the web moved on it was necessary to keep writing a lot of code to support IE and that held the web back as well.
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On Saturn's moon Titan, the gravity is low enough and the atmosphere thick enough, that by attaching small wings to your arms, you could fly like a bird.
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Flight is a matter of balance. Gravity's always pulling you down, and if you want to stay up, you need to generate enough lift to balance it out. Where does that lift come from? Birds' wings are shaped so that air on top has to travel further than air on bottom to go around it . That means air on top of the wing is traveling faster than air below. And faster air exerts less pressure. So the air above the wing is pushing down with less force than the air below the wing is pushing up. This difference is what keeps the flier flying. In Titan's case, lower gravity means you need less lift. Denser atmosphere means more air, meaning the difference in speeds generates more pressure difference, so more lift. Both make it easier to fly. .I'm going to actually explain like you're 5: It's basically the same reason you can "fly" in water more easily than through air. Not only does is make "weigh less", but it gives you something to push off of mid flight.
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If an alien probe with similar dimensions and operational capability of the Pioneer or Voyager spacecraft passed through our solar system, would we detect it?
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It's possible but there are some caveats. The farther away you are from a source of light or radio waves, the lower their intensity will be. So something twice as far away from you, will only be 1/4 as intense . In order for us to talk to our own probes we have to combat this loss of signal over long distances by using a very directional antenna and pointing it in the Earths direction. Kind of like cupping your hands around your mouth to shout in one direction which amplifies your voice. In order for us to detect an alien probe it would need to be very bright, very loud, or very close to us. If it used a directional antenna to broadcast in a narrow beam back to it's origin, if it wasn't pointed right as us we might not hear it. If it had a low albedo we might not see it unless it were very close to us. Even finding satellites orbiting the Earth can be difficult without knowing their orbits. It's how spy satellites work. They go in eccentric orbits, are painted very dark so they don't reflect much light, they broadcast seldom to prevent eavesdropping, and they may even have radar absorbing paint on them. Radar however would likely locate a probe if it were large enough, and we happened to be pointing radar at it and listening. Earth based radar installations can project pretty far out there, but we usually aim them at very large objects that we already know are there. To catch a smaller object we would need more listening stations, and more powerful radar scanning the space around the solar system.
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How can we know that the observable universe is 46.1 billion light years in radius, when the furthest object we can see is 13.3 billion light years away?
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I honestly don't fully grasp this but I'm still trying.. But I recommend learning about Einstein's relativity. A book or audiobook.
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What’s the difference between an embassy and a consulate?
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I'm going to use my situation as an example here: Canada has their embassy in Washington DC, which handles all of the official gov't-to-gov't business. They also have a Visa Office that handles all of the minor citizen level stuff: Visas, Passports, etc. There are also Consulates in Atlanta, Boston, Chicago, Dallas, Denver, Detroit, Los Angeles, Miami, Minneapolis, New York City, San Fransisco, and Seattle. All of which handle the same Visa office stuff, as well as more US company-to-Canadian Gov't business. They also get involved in Canadian Province Gov't-to-US State Gov't business. Mostly trade related stuff. The head honcho of a Consulate is called a Consul General, all of which answer to the Ambassador of Canada in Washington DC. There are also Ambassadors of Canada to the [OAS] and to the [UN] both of which are the head of the Permanent Mission of Canada to their respective organization. I mention the OAS and UN because they're both located in the USA.
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Difference between lobbying and bribing?
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There is a huge misconception that lobbying is just bribery. In reality lobbying is much broader. If you ring up your representative, you are lobbying. If you present a report to a representative, you are lobbying. Basically any contact with MP's/Senators for political purposes constitutes lobbying. The democratic process *relies* on lobbying.
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what is a reverse mortgage
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Worst part about them is that since you are not making a payment, you are not paying interest, so the interest compounds on itself. Over and over, snowballing until the end. If nobody is inheriting the house, then it doesn't really matter.
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Is the universe actually infinite, or does it just go beyond our current observational capabilities?
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The only real answer is: No one knows. As far as we can see it's infinite, there seems to be no sign of it ending or changing in any direction. But there is no way we can know that for sure right now.We will never see beyond the distance we currently can as the universe is expanding faster than the light from beyond the observable universe can reach us.That's one of the fundamental questions physicists, cosmologists, and astronomers are trying to answer.
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how can the universe be finite? If it has a putter boundary, doesn’t there have to be something (even empty space) beyond it?
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Ah the old what's beyond our observable universe question. Simple answer is no one knows if it's finite or infinite or whatever. It's pure speculation.
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Why is a small amount of inflation considered good for the economy?
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Small amounts of inflation encourage spending and investment. If you're money becomes more valuable over time , then why buy a house/TV/Car now, when you're dollar will be worth more next year? Or why take your money out of the bank and invest it? You're basically able to make money by just burying cash in your backyard. So why risk the market goes down? Why would a bank lend out money? Who needs to take a risk that lendee won't be able to pay it off? You're gaining value by letting it sit in your vault. All of these things lead to shitty economy, less spending, less movement of money, less jobs, and overall a worse standard of living. A small, controlled amount of inflation helps stimulate the economy.
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What happens in our body that makes our bones make a popping sound when we “crack” our knuckles, back, neck etc..?
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No one knows for certain. One theory is called cavitation. Where compression of a fluid causes gasses in the fluid to become bubbles. Those bubbles then rapidly go back into solution once the pressure decreases. This is why on a boat propeller you see bubbles around to propeller when you move fast enough The idea is the synovial fluid in your joints is rapidly compressed and released during a cracking as the goes from one part of the joint to another side through a narrow gap Why this feels good to some and not others I haven't a clue.
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Why do police still use horses?
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They handle terrain, can jump obstacles, fit easily through crowds, and provide a height advantage. Also people are afraid/respectful of horses, and in the rare instance they get attacked they'll be trained to rear and strike.
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If you have two objects moving at the same speed, the one further away appears to be moving slower than the one which is closer. Why?
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Things that travel the same speed go the same distance in the same amount of time. When things are far away, very large distances look small. So even though both cars are going the same distance in the same time, the one farther away doesn't look like it moved very much which makes it seem slower.
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Why is the reversible, and compact design of USB-C only made recently? Why couldn't they have used this design decades ago when they were designing USB-A?
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USB in and of itself is an attempt to condense parallel communications into a serial interface. When USB was designed, they condensed 8 pins to 4. I am not trying to say the original RS232 port was parallel, it was serial; but the logic to achieve the same ability with fewer pins was one of the main priorities when USB was designed. Fewer pins + more data throughput = much beefier controller chip needed. It should be noted that only in the last few years has technology become cheap enough to push the limits of the USB standard. Which also means that the designers for USB had already attempted to use the most powerful controllers they could. This entire conversation is more or less a display of how technology 'know-how' doesn't always keep pace with the literal technology available. The technology exists to push the standard much farther, but the price per controller is holding it back. Remember, BILLIONS of devices use this standard.
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How do life insurance companies make money
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1. They invest your premiums and make money on those for years before having to ever pay out. 2. Many people get Term Life insurance, and those are not permanent, so if the term expires and you didn't die, then the company gets to pocket the premiums you've paid into it. 3. Many people may cancel coverage due to the cost of premiums or other reasons, and so they pocket premiums prior to the cancellation. Some insurance policies have cash value payouts that people take which forfeits their policy, but gives the consumer some extra cash. The insurance company then gets to end their liability for that customer.
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What does it mean when we say the universe is expanding?
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We don't know what it is expanding into but all our findings indicate that everything is moving away from each other and at an increasing speed. If everything is moving away from each other then that is why we call it expanding. On another thread someone used the image of a balloon being blown up. If you are on the surface of the balloon while it is being blown up all the other things on it will be moving away from you.
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Light is the fastest thing in the universe but WHY does light travel/move at all?
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One way to consider this is to think of light as *information* and the current arrangement of the universe as *state*. If information doesn't travel, then state never changes. If information travels instantaneously, then all possible events happen simultaneously. In both cases, you no longer have any reasonable definition of 'space' or 'time'. So, philosophically, information must alter state at some non-zero/non-infinite speed for it to be worth the bother studying in the first place.It’s not some all-encompassing state of the universe. As we have come to know it, it’s an actual “thing”. Acting as a wave and/or particle. I just don’t know what it REALLY is.
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Why don’t we milk pigs?
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Mainly because they don't produce enough to justify the effort. Sheep's milk is available in some places as well, but it tends to be more expensive than the alternatives because of the effort involved in getting enough of it to market.
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Why do some soldiers guard Grand Central Station and The Oculus for example, and others are deployed overseas? How is this decided?
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While I don't personally have experience in the military, I have a few family members who have served and a younger cousin active in the Marines. My understanding is that you don't get to pick where you get deployed, so these kind of assigents are very difficult to get. While someone would be pretty lucky to get this kind of assignment, it's not decided by chance. Like any job, candidates are selected if they are highly qualified for the specific duties of the position. Something else I want to add - in many high-traffic areas like NYC there are plainclothes officers mixed into the crowd. So while they may not be visible, security is definitely around!
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Why are standard golf balls white instead of a more vibrant color that's easier to see?
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I've heard that white is the easiest to spot. Unless it's in snow of course. A survival guy on his show tore the white foam out of his neon orange life jacket to use as a signal for help for this reason", 'A lot of the bright ones are harder to find. Bought a sleeve of neon yellow the other day and lost them all on decent shots. Rough couple feet of the fairwayWhite is actually easier to see, but if your playing with someone with a different color ball, it can come in handy identifying ownership.You can get balls in different colours, and I do occasionally buy yellow balls. The thing is, it's not always easier to see those other coloured balls. Blue, you can forget it in darker areas and if the grass is dark. Red is probably the most visible, but pretty annoying to look at. Yellow is great, but it depends on the vegetation of the area, time of year and day, etc. Yellow can be harder to see.
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Organ transplants- needing a donor match, but you still need life-long immunosuppressants. What exactly does a donor match entail then?
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If you have a closer match, then you'll probably have fewer problems with rejection. Like if you have incompatible blood types, then many problems will arise immediately and you'll have organ failure very quickly. If you match on some protein markers, you may have a better time than people who match on no protein markers. Organ donation is very hard on the donated organs. They don't last forever. Average amount of time a donated heart lasts is 10 years. For kidneys, I think it's around 20 years. A worse match may last a shorter length of time.
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Why can hot things of any kind get colder than room temperature?
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Food contains water - when the water evaporates, it cools the food. This will happen so long as the relative humidity in the room is not 100%: any moist surface will be cooled to below room temperature. Edit to add: An example would be the temperature difference between a [wet bulb thermometer] and a dry bulb thermometer. The latter measures what we refer to as the ambient temperature or 'room temperature' if you're indoors, and the former uses evaporation to reach a lower temperature. This has been a standard and accurate way of measuring humidity for centuries. Anything with a moist surface - including almost all food - will stabilise at a temperature lower than the ambient temperature, unless the relative humidity is at 100%. Indeed, humans even use this mechanism to stay alive. If it were not possible to use evaporation to cool something below the ambient temperature, then any air temperature over about 38°C would not be survivable. As it is, people can sweat, allowing them to control their body temperature at higher temperatures. Indeed, the health impact of severe heat is mainly down to the wet bulb temperature - heat and humidity, together, are the risk. This fits normal experience: a hot and humid day feels worse than a higher thermometer temperature with dry air.Something in the room will not get colder than room temperature without something else taking its heat from it. Can you be more specific? Some things feel colder to us than other things but their temperature is the same. Sitting on a piece of metal and sitting on a piece of wood - the metal will feel colder to us because metal is better at transferring heat out of us than wood is. But their temperatures will be the same.
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How does a casset to auxiliary adapter work?
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The cassette adapter replicates the magnetic strip of cassettes by transmitting the mag strip's signal to the cassette player's head. If it helps, imagine how your phone transmits sound to your ears through your headphones, but in this case your ears are the cassette reader.
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Why are we told to only put Deoderant on our armpits, when our entire body sweats.
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There is apocrine and eccrine sweat glands. Eccrine glands are on most of your body. Armpits have apocrine glands. When you hit puberty your armpit sweat glands become active. The difference in what apocrine glands emit causes the bacteria in your armpit to give off a smell. Eccrine glands don't really smell.
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Why do racing bicycles have ultra thin tyres to make them faster, but the fastest motorbikes have very wide tyres?
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On bicycles: less rubber on tyres make them lighter, which means they are more energy efficient. On motorcycles: energy efficiency isn't really a problem, so they have very wide tires to get a larger surface area for grip, wider tires are also better for proper cornering, like full on laying into the corner a few cms from touching the ground, which is needed for racing bikes.
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How come when humans touch power lines, they instantly get electrocuted, but when pigeons and other birds rest on power lines, nothing happens?
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When a bird lands on a power line it doesn't get electrocuted because it is not touching the ground, electricity wants to go to the ground so when humans touch it their bodies are perfect conductors since we are 70% water
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During WW2 why didn't the Allies replicate the MG42 when it was superior to their variants of machine guns
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The mg42 on its own was a very good gun. If you wanted to put large quantities of bullets down range, then the mg42 is probably the best gun for that at the time. The problems with the mg42 are largely logistical in nature. First the things are not accurate at all. This is fine if your fighting a defensive war, but spoiler Germany tried to fight an aggressive war during even after that was no longer possible. Compare that to a British bren who could flank an enemies line and suppress the entire line until an advancing unit was basically on top of the enemy. Can't do that if you fear shooting your own men. Secondly, the MG42 was not the easiest gun to move in comparison to things used by the allies. The British bren gun was quite easy to move and could be fired from the shoulder. In comparison the MG42 pretty much had to be shot from the ground meaning the gunner had to set up a position in advanced to actually do anything. It cost maybe a minute of time, but sometimes you really don't have that time. Finally the MG42 chewed through ammo. It ate more ammo than the gunner could realistically carry, which means the riflemen in the unit also had to carry ammo. The lead to quite a lot of german riflemen not shooting their rifles. This meant that any unit with an MG42 was pretty much only the MG42 and a bunch of armed guys defending it while feeding it ammo. The MG42 was a perfect gun made for the wrong war.
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When metal rusts, does that mean we can never use it again? Could we completely run out of metal?
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Iron we mine and turn in to metal is Iron oxide. It takes tons of energy to to remove to turn iron oxide to iron. There is a ton of stored energy in the Iron and it wants to react with the oxygen in the air to turn back to rust. odd factoid- metal only rust or oxidizes on earth due to its oxygen in the air. The oxide layer keeps metal from sticking or welding its self back together. SO if you have really clean metal in space that doesn't have a layer of oxide then it will fuse back together. Kinda like 2 water drops touching then they form 1 water drop. They have special tools in space designed so they don't cold weld back into 1 peice", 'No, you can melt it back into pure metal. And only the very surface of the metal rusts, the integrity of it stays intact.Most metals don't rust the way iron does. Aluminum, silver, and copper form an exterior coating. Gold and platinum don't oxidize at all.
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How come American football kickers can 70+ yards on kickoff but only around 50 yards on a field goal. The holder can’t make that much of a difference can it?
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This isn't really a physics thing. It has to do with the rules of the game. A field goal actually has to make it 10 feet off the ground to count . That's where the extra difference goes. A kickoff/punt can hit the ground, bounce and the extra distance will still count. The holders/tees have nothing to do with it. If a kicker makes a 50yd field goal, the ball would keep going if it weren't for field goal nets, thus potentially picking up another ~20yds to make it the same thing as a free kick.
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If water is a incompressible fluid why does pressure increase when going under water? Wouldn’t the pressure stay the same since the density of the water doesn’t change?
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Let's imagine you lay down on the ground. I put a bucket on your chest and start filling it with water. You will feel the weight of the water pushing down on your chest. That force/pressure of the water pushing down on you has nothing to do with the compressibility of the water and everything to do with its weight. It's the same thing if you go diving, but the force is just spread out all the way across your body because you're completely surrounded by the water.> If water is a incompressible fluid why does pressure increase when going under water? * The pressure comes from the weight of the water. * The weight comes from the mass of the water being effected by gravity. * The farther down you go the more water is above you pressing down. The more water, the more mass, and the more mass the more weight, and the more weight the more pressureMaybe not an answer, but as you go deeper, the weight of the water above you is exerting the increased pressure.
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Why do couriers in the USA leave package in front of the door?
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When I lived in a big city, the mailman had a key to get in to the lobby of the building and put stuff in our mailboxes, or leave a package on the floor. UPS, FedEx, and DHL did not get those keys, so they'd leave packages on the sidewalk if they couldn't get someone to let them in. One of my packages was stolen . After that, they would no longer leave stuff at the door, I had to go pick it up from a florist shop a block away. They closed at like 6 or 7, so it was always a pain in the ass to get my packages. Now I live in the suburbs, and they can just leave stuff on my front porch. I think the only thing that has to be signed for is really expensive stuff, or alcohol.Delivery type. You can choose to have it left at the front door or that a person must sign for it to be delivered', "This is actually weird, cuz in Romania I don't think you have the option to leave it at your door. Even if it's something minute as a thumb drive.
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Why do radio stations have to play the same 30 songs, day in and day out?
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It's called commercial music because it has been approved for commercial use. You've got all kinds of people listening, different religions, different ages. To keep it simple, you have to try to keep everybody happy and commercial songs are a good way to stay safe.
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Why do humans' teeth rot and fall out if they aren't brushed, but animals' teeth can do okay without being brushed?
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The majority of our modern day tooth decay issues stem from the ludicrous amounts of processed sugars in our foods . Most animal feeds don't have these, so less of an issue. Also cultures which likewise don't have a lot of processed sugars or sweets tend to not have as many dental problems either. By all measures I'm terrible for tooth brushing but neither do I eat a lot of processed foods or sweets, so I've lucked out with few cavities.
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Why do printers use cyan instead of blue?
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The actual color spectrum goes from ~350 nm to ~750 nm. However, the way you see is via 'cones' that have their maximum gain at center wavelengths ~475, ~550, ~700 . So if I shine a light with a wavelength of ~515, you're actually seeing a dim blue light at the same time you see a dim green light - and you interpolate that it's somewhere between blue and green. Interestingly enough, you'd see the exact same color if I shone two dim lights - one @ 475 nm and the other at @ 550 nm. Your eye can't tell the difference between the two colors and the one color in the center. As a result, it makes sense when projecting light to just match the emitters to our eyes. Because you're 'faking' the intermediary colors anyway, you might as well fake them with the same parameters as the eyes that will perceive them. However, when you're dealing with reflective light, you can't really do this all that effectively. If you tried to 'paint' individual pixels to mimic the RGB approach of monitors, you end up with something like: _URL_0_ Instead, what we do is mix colors togethers and generate the true colors - and then let our eyes interpret them as they do any true color. When you're mixing colors togethers, it's far easier to work with roughly equal sized frequency bands in the color spectrum rather than trying to match the lopsided nature of human visual perception. Note: This also means that what appears true-to-life to us on our monitors will often appear bizarre to other animals with different color perception.
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Why are window air conditioners generally noisy, while indoor cooling systems like central air so quiet?
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1. AC units for central air are still pretty noisy. 2. The larger the fan blade, the slower it needs to rotate to move the same amount of air. A window unit can only have a blade so large. The faster it spins, the more noise it and the motor driving it are going to make. Also, your A/C unit outside is simply using its fan to blow air over the heatsink to cool it off. The furnace's own fan is used to move it around the house.
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if temperature is a measurement of how much motion particles have shouldn't a fan make it hoter instead of colder?
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Temperature is about the local motion of the particles and the energy released as they bang into each other -- think vibration. Air is made up of gasses, which are particles spaced widely apart. As gas molecules get more energetic, they move further apart due to their lower mass. As such, the air actually does warm up when the molecules are vibrating faster; as a result we get weather systems with high and low pressure . Now what you're doing with a fan is changing the direction of movement of the gas; the only place where this will increase heat is where the mobile molecules are banging up against the stationary molecules along the edge of the airstream. This can be seen as well by moving an object through water; it creates heat along the edge of the movement zone, but from the perspective of the water molecules in the middle of the stream, nothing much has changed, so the relative temperature remains the same. The more conductive a substance is, the more it can pass on the molecular motion from one molecule to the next, which results in heat transfer. Air isn't that good at conducting, and so doesn't transmit heat well, just as it doesn't conduct electricity well. Does this help?", 'The fan blows fresh air towards you, and prevents stagnant air from staying near your body. The fresh air may be cooler, and is also better able to absorb moisture , which is one of the main ways humans cool offMoving 81deg air feels cooler than standing 80deg air. Because your body works to dissipate heat by sweating water and letting it evaporate. Moving air is more conducive to evaporate water than still air.
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Why are US voting machines is so vulnerable?
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They're made by the lowest bidder. The lowest bidder then turned around and hired the cheapest programmers he could find. Those programmes did the bare minimum to not get fired.It is very, very difficult to get software right, unless you paid a lot of money for it Relevant XKCD: _URL_0_
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The mechanisms of voting in the US and the controversy about requiring government ID in order to vote
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Other people are saying it in more detail, but in essence the root of the problem is that actually getting appropriate ID in America is *unspeakably* difficult compared to in most other first-world nations.
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Why does science show that we sleep better in a cold room, but during the day when are awake a cold room is used to keep people awake and alert?
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I could be very wrong but I always thought they set temps lower cuz it's easier to add a layer than remove one. Hadn't even occurred to me it was done for productivity
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Why is it so many languages have some form of "mama" and "papa" as one of their words for mother and father?
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bababababa", and "papapapa". This is the main reason mama and papa are so preserved globally as labels for parents. This is according to the developmental pediatrician I worked with.
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Why is Malcolm X so celebrated? Wasn't he a racist?
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This is probably too big a subject for an ELI5, but the TL;DR is: He was a person who was willing to make enemies and die for a cause, and the cause was just, even if in the process of promoting the cause he sold his soul. The cause was policing the police, for ALL people. The Black Panther movement isn't exactly what you'd expect from reading a Texas school history book. See _URL_0_ for more details.He was for the most part, but he was a major source of inspiration for many African Americans to stand up. While many of the things he stood for are counter productive to improving race relations and to improve African American opportunities , what he did do was change to conversation about race. When there are two vocal sides to an argument, most people tend to take a position somewhere in between those two vocal positions. This is true even when one side is being completely rational and the other completely psychotic. If one voice is convincing people that white people are inherently better than black people and should be rewarded as such, and the other side is arguing for equal rights, casual observers will tend to pick position somewhere in between, which is still very racist. If however you have one voice saying that white people are inherently better, and the other saying black people are inherently better, then casual observers will tend toward a midpoint where everyone is equalIt's considered more acceptable for "the underdog" to be racist/offensive/drastic than it is for "the bully". Kicking upwards is OK, kicking downwards is not. Edit: Or, think of it like this: You shouldn't fight in school. If a big bully beats up a little kid, it's wrong. However, if that little kid gets angry and hits the bully back, he'll have your sympathy.
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What is the difference between credit cards systems in U.S.A and Europe?
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Even in Europe there is a difference. In Denmark, the DanCard combined with a Visa is very frequently used. By law, there can be no transaction fees and every store accepts it. I can't remember any time in the last 5+ years I've carried cash in my wallet. We also have Mastercard and others, but the most common is the dankort which draws directly from your own bank account with little delay and no directly associated cost for the consumer.
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Does Ginger Ale and Saltines really help an upset stomach?
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If you have a stomach bug, carbonated drinks and saltines won't really do much, since the vomiting is caused by the bug/virus. On top of that, you wouldn't even be able to keep them down, anything you ate or drank you'd just throw up again. It's more for when you feel sick from eating too much or something more minor like that. The carbonation helps your stomach settle a bit and burping releases pressure which can make you feel a bit better. Saltines are both for helping you retain fluids as well as being a simple food that won't upset your stomach.Not for bugs or virus but for my sea sickness gravol, flat gingerale , saltine crackers and sleepGinger decreases intestinal transit time. In that way, it can help shuttle inflammatory or gas-causing contents to the bowel, where it can be passed. I have an already too-fast transit speed and so eating ginger results in certain diarrhea in 45 minutes for me. For normal people, it can help reduce the typical 8-10 hrs transit time to a few hours, not minutes.
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How do spiders know where to build their webs?
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Just heard this topic on coast to coast am radio program two nights ago. A specialist that deals with gravity stated and he may be a whack job but he stated that a spider sends out a stringer and it detects gravity waves and pulses by feeling that stringer and knows which way to go. He brought up a study that nasa did with several spiders in the space station they experimented with to see if a spider would make a web In space. They didn't but then the astronauts figured the spiders were just dehydrated and gave them water and then they made webs. Well this guy claims that the spiders weren't dehydrated, they used the water to detect pulses of trade gravity. Sounded way outta my pay grade and I was driving but was fascinating. Maybe someone can find that radio program podcast and listen as it was definitely this week.
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How does tap water come out cold?
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It isn't really cold, it's usually right around room temperature. However, room-temperature water feels colder than room-temperature air because a liter of water has a much higher heat capacity and heat transfer coefficient than a liter of air does. In other words, water wicks heat away from your skin faster than air and that's why it feels colder. It works the same the other way around too: You can stick your hand in a 212°F oven for probably like half a minute with no harm, but stick it in a pot of boiling water for even a couple of seconds and you'll get scalded.Yes the pipes are underground and also that is why it generally takes a bit of time running the tap to get to the colder water that is further away into the cool ground. The warm water comes from a separate pipe. Do not use hot tap water for cooking or consume it in any fashion.
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Why do so many game devs tie physics and other calculations to frame rate?
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You're kind of misunderstanding the issue.Devs don't do it on purpose necessarily to mess with gamers, but it's something that can be remedied with properly planned programming. So let me explain it as simply as I can without too much game dev garble. When programming anything, the speed of the program is automatically tied to the power of the hardware it's running on. Programmers can make their programs run on any platform at the same frame rate using an added calculation. Games for consoles only are usually programmed directly for the consoles specifications, and therefore programmers neglect to plan ahead with these added calculations. So if a programmer doesn't plan ahead, a PC port can prove to be glitchy, because PC gamers usually run hardware much higher than current consoles. Hope it clarifies a bit. Edit: This answer is 100% correct. Downvoting it won't make it any less right. Source? I'm a game developer, with a degree in game design. I've programmed and scripted for years.
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How can satellites and spacecrafts be launched just later than planned like it's no biggie?
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I think the key is calculating trajectories for numerous launch days . When you are running a multimillion dollar operation, it would be kinda ridiculous to not plan for something as simple as a cloudy day. On a slightly off topic note, if you read the book The Martian , there is one brief part where a character discusses calculating launch trajectories for something like 25 consecutive days. While i doubt this ever actually happens, there is no reason why ot couldn't. TLDR: be prepared, have options available.
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Things become slippery when wet, so why is water not used as a lubricant?
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AFAIK what makes streets and surfaces slippery when they get wet is the accumulated grime together with the water. When that is washed off, the street is far less slippery. The other thing about lubrication is film strength. A lubricant keeps two surfaces apart and allows for relative movement without much friction. Water is not very good at that. Try a drop of oil and a drop of water on the kitchen counter, clean your finger in between. You will get through the water film much more easy than through the oil film. The best film strength doesn't help in lubrication when the viscosity is too high. That's why corn sirup is not a good lubricant. Another circumstance can make wet surfaces slippery without grime: Having shoes without profile won't allow the water to leave the gap between your sole and a smooth surface and therefore lead to less friction.
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Why can gas prices be so different between two stations?
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The price gas stations pay to get the gas changes over time. Not all gas stations order at the same time. The price you pay reflects the price they paid AT the time they purchased their gas. Also could be a loss leader. Gas stations can make their gas cheap and lose money, in hopes to get you to come inside and buy stuff. The more expencive gas station could also just be raising the price because they're on the better trafficked side of the road. There's a ton of reasons I guess.
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Why did we start with generation X, Y, Z instead of A, B, C?
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the silent generation", etc. "Generation Y" was originally kind of a joke on "Generation X", combined with "why", but it stuck, although "Millennials" seems to be the more common name now. "Generation Z" is an obvious follow-up, but they're only just now starting to reach the point where they're old enough to have their own "personality" as a group. I 'd bet that they garner a more unique name in the near future.
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Why can you see reflections better off of darker surfaces if dark colors are supposed to absorb light?
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A lighter surface reflects everything, making it hard it distinguish objects from other light that is reflected. The reflecting of light on dark surfaces happens only because the surface is smooth against a dark background, it's easier to discern the reflection.
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How is it that a photon doesn't experience time or distance, yet it (to my understanding) moves through both?
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Only from our frame of reference has the photon been traveling for 8 minutes. Because of the effects of time dilation, the faster an object moves through space, the slower it moves through time. A crazy example is that if you were to travel at 99% the speed of light to our nearest star at 4 lightyears away, you could get there in only a half of a year from your frame of reference. 4 years would have passed for the people still on Earth, but you would have only aged a half year. This is because you're moving through space so fast that time slows down, but only for you. Time goes the same for everyone else and if you were to make a return journey, they would have observed that you were gone for 8 years, while it would have only felt like 1 year to you. Following along with the idea that as you move faster through space you move slower through time, if you're actually able to reach the speed of light , something unimaginable happens. Time stops completely *for the traveler*. The traveler would be able to get anywhere instantly as time for them is completely stopped. What would it look like to someone if time stopped? Nobody knows, and it's also a nonsensical question of me to ask because the laws of the universe prevent this from happening. The photon, a massless object however, can travel at the speed of light. So if a photon could have a reference frame, it would be frozen in time. To a photon, if it were an object with mass, it could get everywhere instantly all at the same time.
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When Ravens were used to send messages how did they know where to go?
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Homing pigeons are selected and trained to always fly home. For what it's worth, here's a picture from World War One showing a guy carrying a few birds: _URL_0_
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We get the internet from ISPs(Internet Service Providers). But how do they get it? (Or how does it work)?
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Mmmm ok, your question caught my eye and I guess I just found a video for you: [https://www._URL_8_/watch?v=IrGMPdseXxI] Look, imagine yourself watching a YT video, then imagine there's this thick, fat, cable going around the world. There are plenty, thousands of them all around the world, and they are buried underground and under the sea. Your Internet Service Provider is connected directly to that cable, and so is Youtube's computer. Let's call it a server, because, you know, that's how it's called. So whenever you typed _URL_8_ on your phone, that information traveled to your ISP, who knows that _URL_9_ is a web page that is stored on that computer, right over here. So the ISP tells Google that you want to see what they have stored in there, and the computer normally replies back, saying: yeah, OK, you can take a look. So that information gets sent out from Google's computer, via that fat cable, to your ISP, and then through the air right up to your phone.
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Why is there so much water on earth? Where did it all come from?
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Hydrogen: most abundant element in the universe Oxygen: third most abundant element in the universe [Source] The question is not why there is so much, but why isn't there more
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why does Canada import and export oil at the same time?
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Couple different reasons. Canada is a very, very big country geographically. Over 90% of Canada's oil is produced in the western prairies . The vast majority of Canada's oil importation occurs on the eastern coast. Tankers are a very cheap method of transportation, so it does make financial sense to actually import it across the ocean rather than across the entire country by land in many cases. This is especially true since there is no major pipeline moving oil east - which is the only way it could even approach being economical ). A lot of the oil Canada exports is also crude, so it's being exported not to a final consumer, but to a refinery.
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What is the practical help to use of having a map of the human genome if everyon's DNA is different?
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Your eye color gene might be different than someone else's but both of your eye color genes are in the same place. Think of it like a big row of switches and dials. They might all be set to different things for different people, but knowing the genome tells us what those switches do, regardless of what they're set to. Whether your eye color switch is set to blue or brown isn't the important part, it's that we now know which switch controls eye color in the first place.
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How does the “cutting” process work for movies/TV shows? Is it simply the scenes the director doesn’t like that are cut?
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Sometimes a scene will be filmed several times, and the best parts are edited together to form the best possible scene. When you have a scene where you switch back and force between camera angles, it almost always was filmed at least twice. Special effects will also require multiple shots, in *Lord of the Rings*, anything with both hobbits and humans had to be filmed from both perspectives. The directory/producer is going to be heavily involved in the editing, whereas the editor is a skilled technician following a someone else's creative directions.
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Why do credit cards have a verification code? Why not just make them 3-4 figures longer and treat the last few digits as a verification code with the rest of the card number?
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There actually at least two verification codes. There's the one you see, for phone/online orders . The magnetic stripe contains another one for swipe purchases they invented cards where the verification code on the back changes every hour, so even if someone takes a picture of the card info or writes it down, they can't use it for long.
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Why is it that sometimes even after sleeping for a decent amount of hours, i still wake up feeling exhausted?
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First, try to isolate & identify the conditions around when you wake up exhausted, including difference in sleep times, activity level during the day, etc. It's possible you have sleep apnea as that's a primary symptom. Other factors may also play a role, since you say it's only sometimes this happens. Either way, it's a good idea to collect clear information before attempting a medical diagnosis or a sleep study, because you may end up having a good night on the night of the study, which would be a waste of time & money & lead to a misdiagnosis. Intermittent problems are hard to solve, and it's up to you to collect the data on them.
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what makes general anesthesia safe?
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It's pretty dangerous. That's why there is one doctor whose job is it to just sit there and monitor your vitals and ensure that you keep breathing.
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Why are video-game fan art commissions sold for money not affected by copyright issues?
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Companies care about their IP because it will make them money. They will permit infringements in their IP and turn a blind eye if they think the infringement will make them money. For example no one sells fan art of their video game characters. They might however sell action figures and plushies . Two big examples. You remember a few years ago there was a meme where hitler was giving this speech and then his staff gave him some bad news and he got all sad about it? And people put in captions for him being told all sorts of different things about current events? That was from a movie Downfall that had a HUGE increase in sales because of the meme. Insanely they tried to police the copyright. No one thought that was a good move on their part and sure enough sales fell. Second example, 50 Shades of Grey was originally Twilight fan fiction. It got changed up to avoid copyright issues. I bet the Twilight owners are to this day wondering if there wouldn't have been some way to include an erotica side to their business to reap the licence fees that would have flowed.
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What causes loading bars to get stuck or slow way down near completion? Is it that developers put the hardest things to load at the end of the progress so impatient users stick around?
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Basically loading bars aren't accurate cause it takes a lot of effort to make them accurate and no one is paying for that. So what you get is a best effort approach. Like maybe you are installing 4 gigs worth of data, and just count the bytes. that's reasonably accurate, except when you near the end, and you are done with 3.9 gigs, but still have to install 100000 tiny files, which goes a lot slower than a couple of big ones. making it appear to stall near the end.
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How does Adblock work, does it alter something in your browser?
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If you think about how a web page works, it's essentially a text file that includes a basic structure, content, and references to other files such as scripts, images, or other multimedia content. Those references effectively ask your browser to go fetch an extra file and add it to the final displayed result. Some of those extra files are likely to be ads. Adblock software works by watching requests to fetch content, identifying the requests that look like they're getting advertising files, and causing those requests to stop or fail. There are several different ways to achieve that, and different mechanisms support different sorts of filtering. Some of the most common methods include blocking web hosts that are known for serving ads, checking filenames for things that look like ads, and so on.
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How do they remaster old tv shows in HD?
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Old old shows weren't captured in TV quality . They're captured in high film quality, then produced downgraded to TV quality so it could be broadcasted at then- SD TV quality. To make these shows HD, all you do is go back to the original high film quality and scan them in as HD. Newer old shows like 80's we're captured in TV quality technology to save on film costs. You can't remaster them as HD because the original source is only TV quality. Shows like Babylon 5, Star Trek Deep Space 9.
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How do people who crack games get said games to crack ?
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Indeed they don't have access to the source files. They have to work with the released binary EXE file as it is. To help crack they typically use a debugger application to step through the raw CPU instructions while the program is running, then editing the file once they find the exact location of DRM check. It could end up as simple as changing just a few bytes which correspond to a single jump instruction. Of course, things can get a lot more complicated with different types of DRM.
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Why do older vehicles have a blue stripe across the top of the front windshield, but newer vehicles don't?
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It's a shade band - a strip of tinted glass to aid drivers driving into the sun. It helps cut down glare and REALLY helps if you can position the tint between you and the traffic light above you to see the lights change when the Sun is practically blinding you.
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How are glitches/exploits/secrets found in video games, surely people don't spend hours and hours trying to find them with only a small chance there's actually something to find?
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You should look up the history of Mario Bros. level 2 speed runs. It's insane the *years* invested by people who stumbled upon and sought after glitches that would cut the time down. There are teams that make mods for games. Historically, this wasn't always an ethical practice, as some mods are meant to cheat. For example, several FPS games have mods that show you relative to your perspective where all other players are in the game, a sort of vision through the walls. This works because your local client has knowledge where your opponents are. How do these mods work? They intercept data passing between modules, typically game data going to the video driver, which they made an intermediate fake. Learning and decyphering the conventions used to encode and pass data, their mod is simply taking advantage of that information, and exploiting how modules are linked together and running on a computer. From a more classic standpoint, say, on an old console, luck and trial and error. I myself remember walking around the original Zelda for the NES and put flame to Every. Single. Bush. On the whole map. I found all the money secrets. Then I got bombs and bombed all the stone walls, everywhere, even in the dungeons, and found the hidden rooms there. Hours and hours spent.
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How does an ice cream maker work?
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The air argument is not correct. It is the formation of specific forms of ice crystals in the mix that give its texture. The constant churning is what enables this. If you don't churn it while freezing, you get large chunks of ice forming. Not very smooth. _URL_0_ > ABSTRACT: The smoothness and perceived quality of an ice cream depends in large part on the small size of ice crystals in the product. Understanding the mechanisms responsible for producing the disc‐shaped crystals found in ice cream will greatly aid manufacturers in predicting how processing and formulation changes will affect their product. This is why refreezing meld ice cream is never the same. You would have to refreeze it in a churn to get it back.
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What is “Ray Tracing” and how does it work?
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[This video] is a comparison of the 3D software Blender's two core render engines, one is a real-time render engine. Basically how all games work today, it's quick but takes a lot of shortcuts. The other engine is the Ray-Tracing engine, used for super high quality rendering but is currently almost impossible to get loading real-time. Eventually with some Ray-tracing oriented graphics cards we might be able to get the fidelity of ray-tracing in our games, it's the obvious next step if you want to really take real-time computer graphics to the next level :D There's a really good ray tracing diagram early in the video too :)", 'Disney Animation released this great video on YouTube which explains it. _URL_1_ Check it out.
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What is a security clearance?
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It's having the authority to view Top Secret and Classified, etc. documents, intelligence reports and so on. It's obviously an important thing for high level government jobs, but it is also necessary for other top private sector jobs that work with the government -- common landing places for people after their government service. Basically, Trump is taking away Brennan's ability to take a job with a defense contractor, consulting firm, etc. who might work on high level intelligence/military projects for which he would need such clearance.Broadly speaking, if you have certain clearances while working for the government, those can translate to private sector government contracting jobs. It’s basically an extra thing to put on your resume, and it means that the company that hires you doesn’t have to jump through as many hoops to get you clearance.The government investigates you and decides if you have a need to access certain levels of information, and if it's relatively safe for you to be allowed such access. If they are satisfied, you get clearance to access data at that level when it's pertinent to your job.
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how is induction cooking different than a typical electric stove top? Don’t they both just send an electric current to create heat?
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In an electric stove, an electric current passes through the coils, generating heat. This heat is conducted into the bottom of your pan, then from the bottom of the pan up through to the top of your pan, and then into your food. In an induction stove, a changing magnetic field is generated by the stove, which causes an electric current to swirl around directly in your pan. This generates heat, which is conducted into your food. Because the heat is generated directly in the pan with an induction stove, it can get the pan up to temperature faster. It also means that the stove top itself isn't necessarily hot, other than insofar as it gets heated up by the hot pan which is sitting on top of it. This makes the induction stove somewhat safer, as you could turn it on full blast and then put your hand on it without getting burned. You won't accidentally melt a plastic spatula or burn a wooden spoon if you set it on the cooking surface. One big downside, though, to induction, is that it will only work in conductive metal pans; because an electric current can't really be generated in a glass or ceramic pot, you won't be able to cook with these.
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