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69z9t8 | Why are people so drawn to shiny things like minerals and gems, especially to the point where they're used in things like fine jewelry and crowns? | Shiny things are usually rare and/or valuable. We put them with other shiny things as a show of wealth or status, like the British Crown Jewels or the Hope Diamond. | b0869c01-abcd-4cf7-880f-2fc53619abee |
4r5b69 | What does growth mean in terms of a countries economy? | The way I learned economic growth, the ways economic growth is measured is by increasing the production capacity the country has (or, in other words, produce more stuff, which then brings in more money when the country exports it). War is famously known to help production (although it also has its downfalls), as the government wants every ounce of resources it can get to produce weaponry and other goods, and hence WWII is usually credited with officially ending the Great Depression.
There's also growth that's caused by better quality of life for the residents, such as technological advances (such as from horse-and-buggy to cars), increased literacy rates, decreased poverty rates, lower unemployment rates, better environments, etc. With these, people are more eager to spend money rather than to spend (such as the "world is ending" mindset many people had during the last years of the Cold War in the '80s), and of course, with more spending, there's typically a healthier economy which leads to more growth. | 0b1f5f57-f708-4466-baa6-2ad5876f0a29 |
16za92 | please ELI5 what the sound is when i put a cup near my ear | [Source](_URL_0_)
The cup (or shell) amplifies the ambient noise, which is the thing you hear.
Many people believe it's an echo of your blood, this can easily be disproved. Try to exercise and put the cup to the ear. The noise is no louder, even if you hearth is beating faster. | dbed26e9-dbdc-42b1-9908-79d2a9a6908e |
8vlu65 | Why do you often feel to hot/cold when you want to sleep? | Your body temperature decreases to initiate sleep. The recommended temperature for a good night’s sleep is 60 to 67 degrees. That’s a lot lower than what I think most houses are at right now. So if your house feels too warm and you’re noticing it when you lay down for bed that’s probably why. I know the first sign every year for me to break out my a/c is when I lay down at night even though it was most likely hotter during the day | 0661dccd-b5df-4c70-9e8d-d3409c5c7aff |
8ovr5b | Is it possible to make an app that is a scale for an iPhone? Since we have pressure sensitive touch, is there a reason we can’t have it measure just how much pressure for small items? | It is entirely possible and definitely a thing, such apps and sites did pop up when 3D touch became a thing with the iPhone 6 release, but IIRC Apple labeled the use of the phones in this way a liability and these apps were removed from the app store, but some websites are still around such as TouchScale. | 44d5e7fc-09bd-4128-b40d-0e83a5ea2c16 |
6iymc9 | when is space where there is nothing but emptiness, what do rocket engines thrust against that make them move forward? | The rocket engines push against the exhaust that is being expelled. For every action, there is an equal and opposite reaction. It's exactly the same as if you were wearing ice skates (standing on ice, obviously) and holding a bowling ball. If you throw the ball forward, you'll slide backwards. This is not because the bowling ball is pushing against the air. It's because when you push the bowling ball forward, you're also pushing yourself backward.
With a rocket, the exhaust from the engines is the bowling ball. | ce18ca12-402d-4166-82f5-5a264dc6b38c |
460ot6 | Why does the law allow companies to purchase or merge with other companies? Why aren't all purchases/mergers viewed as a consolidation within an industry and a step closer to monopolization? | Having a monopoly is not inherently bad or illegal. What is illegal is using your control over a market to stifle competition. That's when the government steps in and companies are broken up. | 6e1f0097-40fe-4f16-859f-09630d10b661 |
445hx9 | Why doesn't the United States FDA create a daily multivitamin they approve of? | Vitamins are not food and they are not drugs. They cannot regulate them because currently they do not have the authority to do so. They (or some other part of the government, I am not sure) would have to reclassify all vitamins to make them a drug and therefore able to be regulated.
Edit: Also the FDA does not make any drugs, they regulate the companies that makes drugs. I am not sure how the FDA changing the classification of vitamins would magically make them more beneficial. | 5b91ad1b-43ec-4506-9628-858b89f040b5 |
oqd4l | Why is Quebec still French speaking? | > why is it the only French speaking region of Canada?
It's not. It's only the only province where French speaking people are a majority.
> How come since Quebec was British owned and subsequently part of an independant Canada, English was not able to replace French?
To avoid uprisings, the British accepted that it would keep its laws, language and religion thinking they would eventually assimilate. People decided they wouldn't and made efforts to preserve those. To this day, Quebec still works on a different legal system than the other provinces.
> Is French still realy the dominant language of Quebec?
Yes.
> Do most people speak it there?
Yes
> What are the languages though in school/shown on tv/ radio etc.?
School teaches some English but not enough to qualify as bilingual. Media produced in Quebec are in French. | 60857f10-068d-4d19-b60e-d7ad02152602 |
1fbhgs | Why does rain make people tired? | It's probably a combination of reasons.
Humans like to be awake all day and sleep all night. And we take our cues from the sun. If it's raining it's darker, so our bodies think, hey almost time for bed! Let's get sleepy!
The other reason is ( I'm not to sure about this one so other redditors feel free to debunk me! ):
When we're in our mommy's belly we're constantly surrounded by the sound of her body, her digestive system gurgling but mostly the sound of her blood circulating. Which is a constant rushing sound. Rain kinda sounds like that, just like a rolling car, or vacuum cleaner. This makes us feel safe and comfortable. And again sleepy.
Fun facts about this: If you drive a long way and don't have any distracting sounds like a radio the sound of your car can cause 'highway hypnosis' causing you to relax and fall asleep behind the wheel.
Babies, when they're tired fall alseep very easily in the car or when a vacuum cleaner is running. Because it reminds them of being inside mommy's belly. | ceccbe33-d283-4a37-a420-900e5bcc11e4 |
32f5jw | How come if I put a lot of pressure on my fingers or toes (i.e. rest my head on my hand) they go "numb" and lose all feeling? | You reduce the circulation dramatically meaning the blood isn't being supplied to the cells including the nerves and therefore they shut down. Restore the circulation and they start up again deluging you with all your missed messages. | 2ce68489-8a16-46f1-a2fe-7b27092b3dc7 |
1pc8c0 | If nuclear waste is the biggest concern over the power plants, why couldn't/wouldn't we just launch the waste into space and into the sun to dispose of it? Or even just into space. Isn't there plenty of radiation there, already? | The rule of thumb, (I think according to Phil Plait's book), given current technology, the estimated cost for launching something into space is roughly the cost of the weight of that thing in Gold, and the cost to get it to the moon would be the weight in diamonds.
To be more mathematical, according to this sourced Yahoo [answers page](_URL_2_) the cost is about $5,000 per kilogram to get something into orbit.
Now, getting something into orbit is not enough, since orbits decay and that would just put the junk right back on earth. Likewise, that $5,000 is based on a space plane that isn't going to scale quite the same. But, combining those too let's say it only costs twice as much to get material permanently out of earth's orbit. (my guess is I am off by an order of magnitude)
The U.S. generates 2,300 metric tons of waste [per year](_URL_1_). That's 2.3 million kilograms. At our unbelievably conservative estimate, that means the minimum cost for launching that material into space is 23 billion dollars per year, just for the United States. For comparison, NASA's budget in 2012 was 17 Billion dollars.
for comparison:
> It’s been estimated that Yucca Mountain – the United State’s current plan to store nuclear waste – will cost about $58 billion to store waste over the course of 100 years.[space.](_URL_0_]
that's only 5.8 billion per year.
And, that's without considering the risk of an accident. Imagine the impact if a rocket full of metric tonnes of radioactive waste exploded two miles above the surface of the earth, spreading highly radioactive material over an enormous area.
***TLDR;*** It is too expensive, and too dangerous. | 3c90ea3d-2bbf-4868-925f-363ef864e7b8 |
4ryd2h | Why does smoking preserve food? | Smoking by itself is actually insufficient to properly preserve foods. Smoke is an antimicrobial and an antioxidant but only protects the outside of food, so it is usually combined with other processes like salt-curing and drying which protect the interior of food from bacterial growth. | 4cc721d5-67bc-4ca1-95ea-83eca422baf8 |
59uz6s | Why when you stare at a moving pattern for an extended period of time and then look up, why everything's wavy. | The conscious image of the world is not a direct input from your retinas. Your brain does a lot of processing to make sense of the world before your consciousness gets the image. This happens for many reasons! Your brain is built to recognize edges and borders, which helps us pick out hiding predators, prey, dangers like snakes, and tree branches to grab during [brachiation](_URL_0_). You're wired to detect faces and emotions conveyed by the expressions. Your brain automatically fixes colors based on lighting and shading. And, most importantly for the thing you're describing, your brain predicts what it should see and adjusts the picture accordingly.
It takes time to process the information from your eyes, recognize the image, make sense of it, put it into context, deliver it to your consciousness, and act on it. It's really damn fast, but it's not instantaneous. To make up for that, your conscious picture of the world is not what your retinas see, it's what your brain a few milliseconds ago thought you should be seeing a few milliseconds later. That puts you in the "present", or at least, a very good approximation of the present.
When you're staring at the moving bottle caps for a long time, your brain gets used to the movement and predicts that the movement will continue. This is great, because it lets you track the moving objects better, since you're anticipating it instead of trying to catch up. When you look away, though, your brain is still predicting movement, and adjusts the image accordingly. Since those things are *not* moving, they appear to wave as your brain predicts their movement, then corrects for the fact that they didn't move, then predicts they'll move again, then corrects again, and so on until it catches on to the fact that things aren't moving through your field of vision anymore. | ab064e9a-84a6-46c6-8b55-cdf12c20fa48 |
7bgayu | Why are Saturday morning cartoons idealized? What’s so different about them as opposed to other days’ cartoons? | Way back when there weren't multiple channels whose only purpose was cartoons. There was a MARKET for cartoons, but not a huge market. What day and time are kids most likely to be available year-round to watch things marketed towards them? Saturday mornings. During the week they're in school. Sundays, might have church. Later in the day Saturday, might have family activities. Parents might even try to sneak in a little sleep by sleeping until 8 or 9, and kids might be able to get up early and watch cartoons. | a58e83ad-74b8-4b01-83eb-c71ab50ac910 |
q9x64 | How do television stations know how many people are watching/ How do television ratings work? | Each TV has a tiny camera in it that is always watching you watching TV. | fbf53227-8226-418f-9562-c81ab1e31d63 |
3m5s0l | What is CERN and what real problems can it cause? | CERN is basically trying to find out the origins of our universe and how everything works by using a very large particle accelerator to accelerate particles to 99.99991% the speed of light and have them collide with one another. When these particles collide they break apart and that is when we can see what holds particles together and how things work. Only problem is that there is years of data to go through and experimentally proving everything will take a long time.
There is no real threat from this, what you see online is just that, "conspiracy theories." People believing that smashing particles will create a black hole and destroy the world. | e2529c4c-3fc3-4927-9533-f4985de5ac19 |
2xnw5u | How can someone just walk away from a home loan? | That wasn't a cause of the subprime mortgage crisis, but more of a result. But that's too much to get into here.
Walking away isn't without consequences. You will get a big mark on your credit rating, which won't go away for 7-10 years, meaning anything dependent on your credit score (including some forms of employment) can be harder than it would be otherwise. New car loans, buying another house, etc may be impossible for 7-10 years.
A mortgage is a "dead loan", meaning that when the underlying security is recovered (the home), the obligation from the borrower is complete. Other type of secured loan don't have this feature, and it's possible for you to get a loan, secured by some security, be unable to repay it, have the security taken and sold, and still be liable to pay the outstanding balance.
So if you bought a house for $200K, and the subprime mortgage crisis hit, dropping home prices in your area so your house is now worth $100K while you still owe $150K, your choices are (a) Keep paying your mortgage for your $200K house, (b) sell the house for $100K, and immediately owe the bank an extra $50K you probably don't have, or (c) walk away, let the bank foreclose, and deal with the consequences.
Ideally, you'd do (a), but if home prices are falling because everyone in your area is losing their jobs including you, or your mortgage is structured in such a way that your payments jump (more on this later), or for some other reason you need to move (congratulations on your new promotion, half way across the country), then you can't keep paying the mortgage, and have to do one of the other choices. Walking away suddenly seems like your only choice.
In the leadup to the crisis, there was a high investor-side demand for mortgages to invest in. The banks sold complicated financial products to investors based on mortgages that were virtually guaranteed to not fail. Business was good, and the banks sold a lot. This meant they had to have mortgages to sell to investors, so they really pushed home ownership and writing mortgages on homes. This lead to some really bad mortgage lending practices that were not good for the borrower at all. A lot of crappy mortgages were written -- these are the "subprime" mortgages.
A "prime" mortgage must meet certain rules: no more than 80% of the assessed value of the property, the borrower can't have too much debt already, etc. Any mortgage that doesn't meet these rules is "subprime", and have a higher risk of failure. So the subprime mortgage crisis immediately implies that a lot of risky loans were being written. Loans that were interest-only for the first 5 years (so a 6% loan on a $100K house would only have payments of $500/month for the first 5 years), but jumped after that. Loans that were structured to be 5 years long, with a large balloon payment at the end, adjustable rate mortgages with a very low intro rate but jumped high after 5 years, etc. The supposed idea was that since home values always went up, a good subprime borrower would, after 5 years, qualify for a prime loan and could refinance on better terms.
When housing prices fell, the subprime borrowers couldn't refinance, and the whole thing fell apart. Homeowners lost their homes, investors didn't get paid on their investments, etc. | 7abfe0b4-d9de-4d36-8d07-87ec16d02fba |
5d0tkm | What is the process of photographers when taking pictures of the supermoon? | There's really not much to it beyond needing that longer lens to zoom in more. Since the moon is being lit up by the sun the exposure times are just like taking a picture of anything outdoors in the middle of the day so it can be a handheld shot.
Think of it like wanting a picture of a specific person's face in the other side of a football stadium. As long as you have a lens that gets you close enough you can get the image you want. | c2a1a566-c7ab-4fe6-b7bb-e91467943b61 |
jh5qz | Gas octanes? | The biggest misconception is that there's "more power" or something similar to higher octane gas. This is not true.
In essence, higher octane means it's more stable and less easy to burn.
Why does this matter, and isn't that kind of counter intuitive? It matters because many of the ways engineers improve an engine's performance requires a more stable fuel.
One common example is higher compression ratios. So when your motor compresses the Air/Fuel mixture in the cylinder, the more it compresses that mixture, the more power it will get when it's ignited. However, with more compression (pressure), the mixture is more likely to ignite *before* the sparkplug actually ignites the fuel.
If you use a low octane fuel, it burns more easily so the chances of you getting premature ignition of the mixture is higher in a higher performance engine. With a higher octane fuel, the mixture will be more stable and burn less easily under higher compression.
The reason it matters in this case is that if your mixture explodes in the cylinder early, you will damage your motor depending on the severity.
If your car calls for premium, you should put premium in it. If it doesn't, you shouldn't. In either case, putting in the "wrong" fuel will negatively affect your car's performance. | 3fea3ea1-def7-4687-8e53-c655b6330e18 |
1qrpxm | Why do we drink cow's milk instead of human milk? | Human females can't produce the same quantities of milk that female cows can. It wouldn't be very profitable.
Plus, notice that we mostly drink milk that comes from animals that like to graze on grass, like cows, goat, and sheep. Humans eat a lot of junk food and other stuff that doesn't make for very good tasting milk. | 29c25aac-67d8-4637-af75-554fee2dd61f |
3czls2 | In Sci-fi movies, why are alien organisms almost always silicone based? | Silicon is the other element other than carbon that would form long complicated bonds that life could evolve around. Though it is almost certain that another life form would be carbon based this gives a way of creating a "totally new life form". | 6f8c8495-e0f7-49f8-88af-8eb6ecb024bc |
j8z0s | LI5, the current patent controversy between the top tech companies Google, MSFT, Apple, etc. | Before the 80s software was covered by copyrights instead of patents where unless you copied something exactly you were not liable to be sued for stealing someone's ideas. However large companies wanted more protection of their software and after some court cases including some at the supreme court they changed the rules and started allowing patents of software ideas rather then just a copyright on the specific code.
The idea was that it would give inventors and programmers more incentive to come up with new ideas as they would have more legal protections from having their ideas stolen. However because patents can be very vague they ended up issuing patents to lots of things that maybe were not new concepts, such as "transmitting data over the internet".
So instead of encouraging innovation it led to companies getting issued patents for simple things everyone did and then sue each other for "stealing" ideas. Also some lawyers saw that big software companies would just payout settlements to avoid going to court and decided to just sue every company with big money with the hopes of getting a fat payout to make them go away.
So now companies will pay lots of money for the patent rights for stuff that should not have been patented in the first place just so they can say "if you sue me for patent infringement then I have patents also and will sue you right back!". It is a huge mess. | 2fe64e03-9792-4199-aa5b-5a9097e56757 |
76byq7 | How are games cracked? | The executable files of a game are basically just a bunch of machine code. Machine code are instructions executed by your computer.
By using a so called Dissassembler, you can turn the machine code into a somewhat human readable format called "Assembler language".
If you are good, you can then analyse the code and modify to circumvent copy protection mechanisms, e.g. by taking the copy protection code out or jumping over it. | 5c114f40-771b-495a-b07f-6b27e907102c |
om0b7 | How carbon dating works | Assume carbon ratios in living organisms within an environment are constant (perhaps it may vary for terrestrial vs. marine). The ratio only remains constant for that orgnanism while the organism is alive (just assume this is due to respiration). Any change in the "known constant" and the currently measured value yields a number of years since the organism died. | 5c500ad3-b199-4309-af44-bdeb87e3f531 |
3immcs | Why is it taking them so long to come out with the oculus rift consumer version, when they developed it nearly a year ago, and came out with the development kits nearly two years before that? | My thoughts are because it is supposed to be a game changer(literally) and to release anything sub par could potentially hurt the concept and make it take even longer for people to get interested in it again, I for one would be extremely disappointed if it was clunky and didn't work as good as I'm imagining it will. | f09b0842-7ee5-4480-8e37-57ccd88e60f6 |
521yw2 | Why do different cheeses made from the same type of milk have different Calcium values? | It basically comes down to pH value of the whey and it's drained. Casein is bonded by calcium phosphate (which is where the calcium comes from) and as the pH decreases it becomes soluble and is drained away. | e820b925-5cbd-4d55-894d-1604654d71a9 |
51z60m | Why does water cause a near perfect hexagon bokeh on camera lenses? | > Basically, how is this caused, and why the hexagon bokeh is always perfectly shaped?
Both of those answers are because it is the shape of the lens aperture of the camera. [This link shows what structure is causing the shape.](_URL_0_) | babbea9f-6f4a-4295-86a1-0a2bd142e1c1 |
5xmcdm | what causes that distinctive smell from electrical transformers, such as model railways? Somebody once told me it's ozone, but why would that be produced? | You get the same thing from lightning strikes. The electric potentials involved have enough energy to break the bonds in ordinary molecular oxygen (O2) and some of the free oxygen atoms can reform to ozone (O3). You need energy to do this because it tends not to happen spontaneously, as the O2 molecule is a more stable molecule than O3. The voltages provide the energy for the reaction to occur. | 706cf52e-be04-4452-b11a-18bc58347262 |
1ziyii | How does insane Clown Posey have such large following, who are willing to do anything for the band? | Because persons are smart, people are dumb
As some comedian said, imagine what average, I mean totally middle of the road intelligent, person is like. Now realize that HALF the population is dumber than that. | 6d4d4538-b848-4586-a763-7ea6ae00743d |
5pzc8b | - if pi is in between the number 3 and 4 how can it be infinite? | It is *not* an infinite amount. It is less than 4.
In *does* take an infinite amount of digits to explain precisely what the amount is, but that's about being precise, not about being huge. | 4eca022a-1ff9-45d9-8b06-bbe403953ab7 |
6k5n43 | ELI5:Why is it that a small animal will run up to a big animal and fight it and the bigger animal will run away? Do animals not know their size? | Because the question in the wild is not so much if you win, but if you get injured. If the large animal stands and fights, yes, it might kill the small animal, but maybe the small animal takes a chunk out of the big animal's leg. Then the big animal has a gimped leg, can't run, can't catch prey (or escape other predators), and it likely dies. | a1c91563-21fb-4583-99b8-d505ba1ff17f |
4b2v0f | How did the idea of weekends come to be? | Henry Ford has been credited with creating the weekend as we know it today. Apparently the normal work week used to be six days, and Sunday was the day of rest. When Ford was paying workers $2 per day (maybe $2.50, not sure), the going rate at the time, there was lots of turnover and constant hiring and training, so Ford decided to double the rate to $5 per day to reduce turnover and keep employees instead of constantly training new hires. At the same time, he also decided to make a five day work week to give his employees Saturday off, thinking they would buy more cars to ride around in for the weekend. The local business community told him he would bankrupt his business. The day after he ran a full page ad in the paper for the $5 per day jobs, there were massive lines of people applying for jobs with Ford. The idea was extremely successful, and the weekend was born. | 0c29feb4-b9f1-438b-b8c0-1c0d28f05896 |
43k92c | "morning hands" | When you sleep, your brain releases chemicals that essentially paralyze you so you don't hurt yourself by moving while you dream. They take a while to wear off though.
Sleep paralysis is an unpleasant side effect of nightmares and waking up while the chemicals are still in effect. | 4b2e86ea-20eb-4c19-b568-3cb6b6047127 |
7xu0tg | What do medals in the Olympics actually do for the winner? Also, what happens if a country wins the most medals? | They don't "do" anything.
Medalling is proof that you are among the best in the world at your sport. That can help you get sponsors and endorsements, and it can help you leverage a post-sports career in something like journalism or broadcasting if you play things right. But there are no special privileges or anything that come with having a medal. | c755908f-b95b-4b02-a7e3-3b4ce998e088 |
3e7tid | Why is there so much apparent public criticism against labor unions when they empower mostly low to middle income workers; who make up the massive majority of workers? | The media is owned by corporate capital and has been shifting culture from progressive collectivism to ineffectual individualism for decades on purposes. The real opposition to Obamacare is not over its actual impact on the economy or personal freedom, it is about squashing any impulse towards collectivism or solidarity and replacing it with self-defeating individualism. "Organized capital and vertical monopoly GOOD and organized labor BAD." Progressive movements are floundering in iterative intersectionality and back-biting while capital prospers unopposed. | 330f0124-fdbd-44f5-afe9-ab8eb61a331f |
2wb491 | Why is there so much focus on colonizing Mars and not an equal focus on colonizing the Moon? | Mars has a number of advantages over the moon, although some of them are still in the speculated-but-not-confirmed category.
Mars has a lot more natural resources than the moon that we can use. Things that are on both, like ice, are more abundant on Mars and there are a number of things not present on the moon at all - notably, an atmosphere. Although the Martian atmosphere is *very* thin compared to the Earth, there's still enough to it that we can use the C02 to convert it into breathable oxygen for settlements. Over centuries, we might even be able to terraform it into a breathable atmosphere. Having an atmosphere also helps a tiny bit for landing things on Mars, as parachutes are an option to assist (although nowhere near as useful as on Earth, retrorockets would still be very much needed). The moon does have an advantage of much lower surface gravity (roughly half that of Mars), but while that makes it easier to get there, it would make permanent settlements less comfortable. Over time, humans in low-g environments develop weaker skeletal structures and muscles, so in the long run, the higher Martian gravity (compared to the moon) would be a good thing.
Then there's the environment itself. First, Mars is a little better off in protecting the surface from solar radiation than the moon because of distance from the sun and its atmosphere. Again, it's nowhere near as good as Earth, but it's still something. But more importantly is dust. Because the moon has no atmosphere, it's dust is *much* more abrasive and tends to wear out moving parts much faster. Martian dust has been worn down by wind, so it's not as abrasive.
Finally, there's the human element - two key factors, really. First, we've been to the moon. It's old hat. Mars is a brand new place we've never been... that gets people more interested. But also, Mars is another step *outward* and away from the Earth. Colonizing Mars shows, much more than the moon, than humans can survive elsewhere in the galaxy with minimal support from the Earth.
EDIT: I forgot to add the day/night cycle. This is important because solar is probably going to be a primary source of electricity for a settlement, as it's one of a very few methods of large-scale power generation that doesn't require large amounts of liquid water (as coal, natural gas and especially nuclear all do - although some forms of solar also do), and wind isn't a great option because of how thin the atmosphere is. The Martian day is only 40 minutes longer than an Earth day, providing a similar day/night cycle. This is important to solar because you only need to store power long enough to get through the night. Contrast it to the moon, which has a 29.5 Earth-day long day. That means night on the moon is about 2 weeks long (dependent on where you are, of course), so you would have to store enough electricity to get through those two weeks. That would take a *lot* of batteries. | 0110193c-81ea-48d8-8edc-56ccc5cf32ae |
2212wc | Why do doctors stop applying a defibrillator after a couple of tries? | Same reason you don't keep turning the ignition key for hours in your car when it won't start -- there's no point in doing it, it won't get better. | 7f180465-fe5c-4e85-8cbb-127d6b636ae1 |
2f1mco | How is it possible to program a computer? How can a clunk of metal understand lines of code? | At the very lowest level, modern semiconductor **transistors** are pieces of lead and silicon arranged so that putting a current on one electrode allows current to flow between the other two electrodes. By itself, that might not sound significant, but think about what happens when we make transistors control transistors.
A transistor can be said to be "on" if current can pass, and "off" if not. The beauty of having these two states is that we can use the **binary code** to store numbers using only on/off states ([explanation](_URL_0_)). Another important thing is that these data points, individually referred to as **bits**, can be stored on wires (low/high voltage), hard discs (magnetized/inert spaces), optical disks (dots/dashes), or cards (slots/blanks). Now, as you can see, there are ways of using massive arrays of transistors to store numbers. Then, using the properties of the binary counting system, we can easily make circuits that add or subtract stored values from each other and place the result in a new memory slot.
Let's get more complicated. A computer works by inputting a stream of bits that form numbers into a vast network of transistors, which do mathematical operations and then spit out new bits. The job of the programmer is to feed the correct bits into the computer's memory, so that they get manipulated by other transistors into the desired result. However, you can see how this is impossible on a modern computer with billions of transistors all connected to each other. Thus, we need **programming languages** to make shortcuts for us. Instead of individually feeding bits into the processor, we can feed it decimal numbers and operations (+,-,*,/). When the program is executed, those decimal numbers get turned into binary numbers (by a circuit that does just that purpose) before being run through the processor that performs the operation and returns a number (that then is converted back into decimal format).
But modern computers have millions upon millions of memory slots, and we can't do useful stuff with just raw numbers. The purpose of programming languages is to "hide" tedious tasks like writing binary numbers and organizing memory so that the programmer can concentrate on **human-understandable concepts** like decimals, words, colors, sounds, etc. For an example on how this works, look at [ASCII](_URL_1_). Each letter is stored by the computer as just on/off states on the hard drive or in the transistors, but with enough of these bits we can store entire books in ASCII or Unicode. Everything we push into a computer gets converted into easy-to-understand easy-to-store binary numbers before it gets manipulated by silicon transistor circuits. | a6fbb184-d29b-4a6b-9780-9aa66eb6dbf5 |
2tpm4r | How is it possible that we are able to find planets far away form the Earth (like Kepler-186 f or PSR B1257+12) but we don’t know if there are other planets in our solar system? | The way we find these planets is to monitor the amount of light coming from a star and then see if it drops slightly occasionally. If it does then that means the star is partially obscured by a planet transiting across the front of it.
We do not have that perspective on planets beyond the orbit of earth as there is nothing bright for them to obscure.
We cannot see them with telescopes because they are too dark and/or distant to detect, the best we can do is look for slight changes in the orbit of objects we can see (such as Pluto) to see if they are being affected by the gravity of something unknown. | 45893594-f623-496a-a2ca-a782e200a951 |
3ae84q | Can someone explain how and why Mark Rothko's work is considered art and how I can appreciate them? | Have you ever seen a Rothko in person? It makes a huge difference. First and foremost, they're BIG paintings. Second, he always wanted people to look at them up close. IIRC he said the ideal viewing distance as 18" (45cm). When you're that close to a huge painting, you literally can't see anything else. Your entire field of vision is consumed by this intense color field. The color kind of radiates on to you. Rothko's work was important because it was a pretty big influence on this notion of "pure expression" or "direct experience". It doesn't operate through language, symbols, or cultural understands. It's mean to be just something you feel, free of associations with anything else. It's important to note that Rothko isn't just important for making this kind of work, but also for talking about it quite extensively. Rothko was a very famous painter even before he started making abstract paintings, and he was quite popular and well respected. His transitions from representational and abstract works, along with his public writing/teaching/lectures/etc. on the subject makes him an enormously important figure in the history of art and the development of contemporary art theory. | 615e00d8-911a-44c5-bd0b-a70ba748f9af |
3fwf0l | Smartphone "rooting" and "crapware." | "Crapware" refers to all of the pre-installed apps that you don't want, but the device will not allow you to uninstall.
"Rooting" means basically taking control of the device in such a way that you can do things that it normally doesn't permit you to do, including uninstalling "uninstallable" apps. The term comes from UNIX operating systems, where, aside from the normal user accounts, there is a "root" account that has absolute permission to do anything it wants, and will not be restricted in any way by the operating system. | bf0c53d6-3f7a-4330-a82b-3446687bb646 |
4chz77 | Why do radio stations only end in odd numbers? | Because of the way radio technology works.
The station you pick isn't actually what you are listening to, you're listening to a range or band of frequencies, rather than just one.
The name of the channel is based on the range of frequencies assigned to it, in terms of the actual frequencies being broadcast to make that channel.
However, it's much easier to call a station 101.1 than "101-101.199" or what have you. 101.1 lies in the middle of the band so it makes more sense than other possibilities | 58b0956f-797d-40e4-9245-075a29ebd850 |
jpsxm | ; Bohr vs Einstein puzzle solution. | The correct answer is that you have the same amount of B in A as there is A in B.
Consider this: each container has 100 units of liquids A and B. The ladle can carry 10 units. In the first scoop, you have 10 units of A in the ladle. You transferred it to container B. Now Container A has 90 units of A. Container B has 100 units of B and 10 units of A.
When you take a scoop from container B, you have about 0.91 units of A, and 9.09 units of B (since that solution is 10/110 liquid A). You add this to container A. Now container A has 90.91 units of liquid A, and 9.09 units of B. However, container B still has the same proportion of liquid A and B after the first mixing - namely, 10/110 liquid A, and 100/110 liquid B. This translates to 9.09 units of liquid A, and 90.9 units of liquid B. | 12bc62a6-5fe1-452c-8483-f6f88fb08f35 |
7tckxa | What does repertoire area mean within classical music? | Your repertoire is the body of works that you have learnt and are able to perform. You may have one or many pieces in your repertoire.
In this context, it sounds like you are being asked for pieces of contrasting style, or from different periods in the history of classical music. If you fulfill the latter, then you pretty much automatically fulfill the first - for instance you could have four sonatas from the Classical period, and you would have to strive hard to make sure they all offered contrasting elements. Or you could choose four different sorts of pieces from the Classical period and show the variety that was present in just one period. Or (and this seems like the safest bet), you could choose four pieces from different periods and they would almost certainly provide plenty of contrast. I'm thinking in terms of Renaissance, Baroque, Classical, Romantic, 20th Century, and Contemporary/Modern periods. There is no end to the variety of different styles and types of work since the 20th Century. | ba42f468-206d-4469-9aff-a80e99ef9c93 |
ztvjx | Why won't Mitt Romney release his tax returns? | Look back on the past two elections:
2008: McCain only released 2 years of tax returns. He didn't get heat for it. Nobody cared. He was rich, and was attacked for being rich. Remember his wife's comment about not knowing how many houses they owned? But only releasing two years of tax returns didn't matter.
2004: Kerry wouldn't release all of his Vietnam service records. He was pounced on, with the attitude "Obviously he has something to hide." The attack worked, it weakened his support. He lost. Everyone still believed he was hiding something. Later, Kerry later released all the remaining service records. Turns out, Kerry wasn't lying at all. He didn't have anything to hide, and he was telling the truth all along. He said he didn't release them earlier because he felt it would be wrong to cave to opponents' requests.
Now here we are in 2012, apparently having forgotten recent history and created new standards.
I'm going to state something anathema to Reddit. Perhaps Romney is...telling the truth. What if he doesn't want to release them because he believes in some privacy? That is most definitely a possibility. But Reddit seems to reject it.
The ultimate answer is, we just don't know. Only Romney himself knows. All this speculation about what he *may* be trying to hide is the same crap that created problems in 2004. And if you think we should be upset about it now, why didn't we care in 2008? | 18a004e0-8c83-4d70-bfe4-1422fc172862 |
6z5n3n | When a small child cries, they often start with the initial cry followed by a long-ish pause, and then they start crying again. Why the long pause? | They need to take a breath for their next cry. Longer pauses adds more intensity when the second cry hits. | c7680a17-0bf0-4329-891a-5370e0b5443b |
7j1n2m | How do brands manufacturing non-concentrated, natural fruit juice keep the taste constant? | I'm not so sure they do. I drink apple juice, grape juice, and orange juice and I notice they do change in taste year in and year out and also season in and season out as the source of the fruit changes as seasons change in different parts of the world. So answer is, they don't control it. Some batches are better than others. | 233e50f0-c54d-4f00-a83a-38fb533bee10 |
3y6pe6 | When people talk to animals or babies, why do they tend to talk in a high pitched cutsie manner, and never talk like they would normally? | The heck where are the comments?
The behavior is called mirroring which we humans have accepted as affectionate behavior. When babies babble in their cute high pitch voices, we also babble back.
When cats miaow, we miaow back. Same with kittens | 6737a8a8-1d53-4002-8ae5-2680b6053803 |
2rbvnp | Why can you not see deleted comments with a permalink, but you can see deleted threads with one? | Threads tend to be deleted because they break some subreddit rule (no joke posts, post must be a question). Comments tend to get deleted because they break Reddit rules (doxxing, copyright infringement).
Of course, either can be removed for the other reason. | 2fccedc1-870f-4afe-8c78-1e433104ca8c |
2cybir | Why do big bags of chips have zero trans fats but the smaller version of the exact same chips contains trans fats? | Because according to FDA regulations, any foods that has 0.5 g of trans fat or less PER SERVING can be labelled as trans fat free.
In big bags of chips, the manufacturer can jiggle the serving size so that each serving will have less than 0.5 g. But small bags of chips are generally considered to contain only 1 serving, and so they can't divide out extra servings to screw with the numbers. | f283cbe5-c8ee-441e-b7a5-d80e9655e18c |
w1oc6 | How do you move? | Our brains learn how to move, and eventually store the information in our "muscle memory"; the stuff that's so familiar to us, our mind can essentially take shortcuts to use it. This is why acrobats can do gymnastics that other people would never be able to perform, even though their actual muscles aren't necessarily any stronger. It's also why babies can't write. When we're very young, we first learn to grip things with our entire fist, then we have to learn to turn over, then we have to learn to crawl. Writing with a pen and pencil takes a certain combination of muscles that we have to consciously learn before we can unconsciously repeat. | 24b24b91-f2f8-48ab-aec1-8ca0de8a0ce6 |
1oi2k9 | Why does China, India, ect. have so many more people than the rest of the world? | Fertile river valleys that create a lot of good agricultural land. The same reason that the Nile delta is so much more populous than most of the rest of the area. There are lots of other similar examples around the world.
It's also worth noting that China and India are *big*. In terms of land area, China is actually larger than Canada. | a0c13494-2fd7-4589-ba81-fa180c65d4d7 |
4i2hv5 | Is burping/belching something you get better at with practice? | Straighten your esophagus. Back straight. Shoulders back. Use your lower abdominal muscles to apply pressure toward your spine then upward. Relax your throat. Project. | ff72dcb2-abe8-4747-a668-0c639f5cbed5 |
1x2gcr | How does electrical grounding work for ships? Why is it so complicated? | It's not about electrical safety directly. If you use a metal hull as ground, especially in salt water, electrolysis can cause corrosion. | 472a0208-a01a-48ac-bc02-434d06b15720 |
86gvrh | Poincaré recurrence theorem | You have a box of m & ms. You shake it and take them out one by one. Put them back in and repeat. If you keep doing this, eventually you will pull them out in the same order as the first time. | 11ac26ba-0b92-496d-9dde-176639007244 |
6ps2zh | Why does 2008 still feel like a couple of years ago? | Probably because with each year that goes by, you have a longer frame of reference to what time feels like? I don't think I phrased that well, but what I mean is that if you are 5, one year is 20% of your entire existence. If you are 50, one year is 2% of your life. So, to get the same feeling of "long ago", it takes more years, the older you get. Same concept as why summers seem to fly by compared to when you were a kid. | 9df474f6-37b2-48da-8edb-13677b03f7dc |
15fpqt | What makes humans want to kiss one another? | > A person receives information about the person he or she is smooching by locking lips, Fisher said. A kiss transmits smells, tastes, sound and tactile signals that all affect how the individuals perceive each other and, ultimately, whether they will want to kiss again.
> Women tend to be attracted to male partners with a different immune system makeup from their own, Fisher said. They subconsciously detect information about a partner's immune system through smell during kissing, she said.
> Research led by Wendy Hill, professor of neuroscience at Lafayette College, looked at how kissing affects the hormones oxytocin, sometimes called the "love hormone," which is associated with social bonding, and cortisol, a measure of stress.
[Source](_URL_1_)
TL;DR: There's much more to kissing than what you might think. One of those is that you subconciously pick up things about the other person through smells you won't notice. There's also this [cracked](_URL_0_) article that explains it quite well, despite being a comedy site:
> It turns out Nerve 0 is directly connected to the regions of the brain associated with sex and gives your nose a direct, private highway to your genitals. Well, that's interesting. What could that be for?
> Scientists theorize that when you kiss someone, Nerve 0 picks up their pheromones and warns your body to start sending blood and good vibes down to your crotch as quickly as possible. It's important to note that Nerve 0 doesn't travel through your olfactory bulb at all, which means you can't actually smell any of the things your sex nerve is designed to pick up. And since our pheromones don't carry very well, getting close enough to kiss is basically the only way your Boning Nerve can do you any good. | 0e4229ed-3196-4d22-ab11-02f71ec49f7a |
37h2lt | How penny bidding sites (like QuiBids or Beezid) make their money? | As far as I know, QuiBids charges $0.60 a bid. So if they see something for $10, that's 1000 bids, and they've made $610. The person buying it gets a pretty good deal and everyone else who bid is screwed. | 076bc832-20e6-4a1d-91f1-6bb2915eeb96 |
1nsl7k | Difference between Special and General Relativity | I'll explain the difference between them, without going into what either form of Relativity actually *is*: Special Relativity only deals with objects (and reference frames) moving at constant speed. General Relativity extends Special Relativity, by figuring out how to deal with acceleration. (Spoiler alert: All acceleration is indistinguishable from gravity.)
Special Relativity doesn't actually require complicated maths either. High-school algebra (variables, square roots) is sufficient to cover the entire subject, making it less complicated than high-school physics (which if you're not using calculus, you're not doing correctly). On the other hand, General Relativity requires ass-butt maths. As in, I have a bachelor's degree in mathematics, and I don't know enough math do to general relativity. It's a topic called Differential Geometry, which *starts* by figuring how out to draw straight lines when space itself is curved. It then goes into trying to count the number of different incompatible ways that you can do calculus to the inside of a four-dimensional sphere (lack of spoiler alert: not yet proven to be finite; generally believed to be more than 1). | bf303592-1ad9-413a-9c9e-4d85a780c21d |
33thk0 | Why do Western movies picture robots and cyborgs like evil beings, but Japan portraits them as the good guys? | This isn't correct at all. Western depictions of cyborgs/robot are often positive (Chappie, WallE, Short Circuit), and depictions in Japanese media are often negative (Bubblegum Crisis is the only one I can think of now because it's been a while since I watched anime). You are seeing a correlation where one does not exist. | 215c866c-ad47-42a1-941b-9eb8249b2c61 |
z9vxd | How are people colourblind? | Inside your eye are 3 different kinds of cells for detecting colors, one can see red, one can see green, and one can see blue. In colorblind individuals, one of those is either missing or not functioning properly, and so the number of combinations of colors you can distinguish is drastically lowered. You can still tell most colors apart because even if you may not see green properly, you'll detect the varying shades of red and blue in that color but you're missing some of the information. | 5a7431ab-7390-40e8-ade6-2b5dec8667c7 |
302vs3 | How does Southern and Northern US Border control work? | What's getting left out is where the border guards ask to see your passport, ask what you're bringing in to the country, and so on. | cfa91925-9944-4349-a3e8-66a98759c663 |
4wcspg | Why do the front wheels of big trucks have such big convex hubcaps and lugnuts? | The commonality across all those big trucks having a doubled rear wheel. On a doubled wheel, you need to be able to bolt the two wheels together to be secure them. The rims budge out so they can touch each other.
& nbsp;
The front wheel can't be doubled because it would interfere with steering. In order to only need one spare tire, the truck using the same wheel across the entire trunk, meaning that the budged rim is used for the front wheels.
edit: spelling | c031459f-9bd6-4fb8-8feb-c75513503e9d |
2fvjtk | What exactly is a G.E.D. and why do people keep making fun of people who take the test? | The GED is the "General Educational Development" test. It is the test that those who drop out of high school, or who fail out of high school take to show that they have learned the equivalent of a high school education. They are made fun of because they have already proven themselves failures by societal standards just having to take the test. It is not a kind thing, but society is seldom kind. | 1947f583-6905-491a-829e-b237c23ed5f5 |
2wdv3z | Why is my original iPad completely useless after only a few years of ownership? | Because the software it's running is made for newer-gen models.
> Is my new iPad going to do this in a couple years?
Eventually, but not for much longer. The newer-gen models are magnitudes faster and more powerful than the first gen. | 2eed6f86-0eb2-4e80-a539-ffd4e6b3d2be |
1m2fdn | how big is the internet? | _URL_0_
Check this out. Pretty much answers your questions. | c83e26a3-2098-443e-9308-21bb98777231 |
67czp0 | How does "artificial flavoring" work, and create something so distinct as grape or other fruits? | It's all chemistry. You start with a real grape and you sit down in the lab and try to figure out what it is in a grape that makes it 'grape like' in flavor. You could physically break down the grape into a slurry, and then use mechanical processes like centrifuges, or chemical processes like solvents and acids to separate the different chemicals in the grape and then examine the individual molecules for ones that create the grape flavor, grape color, grape scent (which is not always the same chemicals responsible for the flavor).
When the chemicals responsible for the flavor and odor of the grape are isolated in this way, their structure can be studied, and using chemistry you can create a method of taking other chemicals and processing them in such a way that they form these same flavor compounds.
Lastly once you have something viable, you test it for toxicity and eventually palletability.
While the actual grape may contain hundreds of molecules responsible for it's subtle flavors, the artificial flavoring may contain only a few that are primary influences of grape flavor.
The substances that create these flavors may appear in many other fruits and flavors as well but in differing ratios so study of grape flavor may discover compounds that are also responsible for berry flavor, or cherry flavor etc. Eventually a working set of "fruit flavors" are developed and over time the secret gets out and they become industry standard flavors.
Many lemon and lime flavors for instance are just citric acid and sweetener. | 21d24c62-ae9c-4167-9617-3848032c6b58 |
1zguzk | Is there any way the U.N. can hit back at Russia diplomatically? | Nope, Russia could just veto it since they are on the security council. It's a fundamentally broken system. | a53b4bda-84bd-4db7-bd41-1d6b2ee85f1e |
1yrxx3 | How are wells built? | Wells are not technically built, they are drilled.
In reference to a water well, a company will do some research to see if they can drill a well in the desired area. This all depends on location, ground type, and various other things. If a well is drillable they will bring out a truck, that is basically a small oil derrick, and begin drilling the well. Depending on you location and ground type the depth of the well will vary.
Some places have underground "rivers" and can be relatively shallow wells, on the other had, some need to be deeper so that more water will seep into the vacant area that is created by the drilling.
Once the well is drilled you can begin getting water from it using a bucket or a pump.
This is all i know.
I hope this answers your question.
Resource: had a well drilled on old property.
Please correct me if I'm wrong. | 9214546f-1000-47e4-8113-3cd1e5b6b3df |
4xfnic | What makes raindrops large sometimes but small other times? And is the size of raindrops indicative of how much longer the rain will fall? | Raindrops form when water vapour in the atmosphere clusters around microscopic solid particles (such as dust) in a process called nucleation.
Nucleation is reversible. As water molecules attach themselves to cluster, other molecules are leaving. There is a point called the *critical nuclear size*, at which point the cluster of water molecules is stable. This is the point at which a raindrop forms.
The critical nuclear size /critical radius is controlled by temperature. The mathematics tells us that as the temperature is lowered, the critical radius decreases.
Hopefully this answers your first question, and if I'm wrong I'd very much like to be called out on it! Cunningham's Law and all that ;) Ultimately, though, the answer lies in thermodynamics. | 6efaa414-2ded-420f-9fff-7c3f2fe86d53 |
5bsyei | How are space agencies sure they are not contaminating Mars/TheMoon, and why do they care? | Well, they use very rigorous clean room techniques to minimize the amount of biological contamination that is on our probes. Beyond that, the harshness of the environment is likely to whittle down at least some of what small amount they miss. But they are not sure they are not contaminating the objects, they probably miss *some* stuff. Not that either environment is especially conducive to life as we know it. The Moon especially, although some things may be able to eek out at least survival on Mars, if not prosperity.
They care because we don't want to substantially alter the environment we are studying before we study it, and just in case there could *be* anything alive there, it'd be a shame to accidentally destroy it with competition. Additionally, if we go to all the work to find life and then bring samples back to Earth, it'd be a real bummer if by the time they got here it as just good ole tardigrades or something of the sort. | 31c04ab3-555b-46b9-9a21-1c4e153fb1da |
4x2su8 | Why aren't we concerned with bacteria, viruses, and other microorganisms developing resistance to alcohol, chlorine, and other substances used to sterilize medical equipment (and hands)? | It is a good question. The answer is how it works on the organism. Anti-biotics work by interfering with some important function of a bacteria cell. Think of throwing a wrench into a machine and watching it gum up the works. Cells that have different machine arrangements can be more resistant to wrenches. They'll have casings around important stuff or gears that can allow a wrench to slip through the teeth without stopping. Maybe they have extra redundant machines.
Alcohol, chlorine and copper work by physically dismantling the machine. No amount of changing the machine will help when you shown up with a screw driver and start removing things. | 7bc9544b-7870-4848-94f3-27c895cfb67e |
1lunk9 | How do we 'die'? | * To kill by breaking someone's neck you need to sever the spinal cord, thus breaking the link between the brain and the rest of the body thus stopping the beating of your heart and lung function
* Blood carries the necessary oxygen to the cells in your body so a major blood loss can stop your cells from functioning, and enough can cause organs to stop working
* Severe head injury can cause a break in the link between your brain and your heart/lungs
* Dying of old age mainly is a standard infection or illness but your body is weak enough to not combat it | 176cb7f2-a229-4a7e-8271-e2b1e2d9f1ed |
24g4e0 | How did the commonality of "seeing the light" originate when people are "crossing over" or passing away? | When your brain is deprived of oxygen (which is generally happening whenever the thing that's killing you is, you know, killing you), your brain shuts down different parts of itself in a given order, in an attempt to keep you alive as long as possible.
Turns out, when the visual centers of the brain begin losing oxygen, you start getting tunnel vision, plus you lose the ability to see color, which means whatever light source you look at starts looking like the "light as the end of the tunnel", even if you happen to be staring at a streetlight or something. | c9ba131a-642b-4624-ac7c-a1e75c7a600b |
7ecd8i | Why is it harder to be happy as we grow older? | There are a lot of possible explanations, someone might be able to link to studies but let's go for ELI5 and speculation.
New things are very exciting to your mind. The first taco you eat is AMAZING. The first time you play a video game it blows your mind. The first good book you read is SO POWERFUL. So you keep doing these things.
But after a while, you start running out of practical new things to do. You can try new restaurants, but eventually most of the menus have the same things you've eaten at others. You can play new video games, but after you've played a few dozen it's hard to find one with completely unique mechanics. After a few hundred books, you can't find many new plots. See the pattern?
A lot of people get bitter and decide this means new things are worse than they used to be. This isn't often true. But it is true that there's no way, in 2017, to recreate the feeling you might have had playing Super Metroid for the first time in the 90s. You already played it for the first time, it's hard to be surprised in the same way again.
The best thing you can do is desperately keep trying to find new experiences. Or get a really nasty case of amnesia.
There are other bad things that happen to adults. We get in debt. We love, and lose. Sometimes people hurt us. Sometimes we hurt ourselves. Time isn't very nice to very many people. That tends to have a very bad impact on how "happy" you can be. | 831987fb-714c-498f-828e-f49ea4e8739e |
o70qp | Brainwaves. What are they? And can sounds of certain frequencies have an effect on them ? If so , why? | What do you mean when you say brain waves? If you are thinking of the readouts of machines like EEG's or similar devices what you're seeing on these machines is the electrical activity of certain areas of the brain that are picked up by the electrodes of the machine.
Because most brain activity is a chemical exchange based on the electrostatic gradient, there are no "waves" or sound waves involved. What you are measuring with these machines are the minute changes in electrical activity in certain areas of the brain.
Hope this helps a little. | a3210718-0ba9-4abe-92d8-8ff780f72c9d |
88yvn4 | What is Markov Chain and why is it important? | A markov chain is a mathematical approach to disentangling several possible events that depend on outcomes before it.
To stay topical, take a look at March madness brackets. You have a pretty low chance of getting your bracket right. But if we apply some really simple logic, we can increase that chance.
If you fill out the bracket as a set of unorganized fill in the blank boxes, you won't do well. For instance, you could have a team that you eliminated in the sweet sixteen winning the final four. That doesn't make sense. Instead, let's create a chain of causes that predict the inputs into the next block of causes.
If a team doesn't make the first round, they can't end up in the later rounds. Better right?
But if we have even more information, we can do even better. We could fill out our bracket *as* the tournament is happening and expect to do really well. A player who lead scoring got injured in the elite 8? We can use that information to reduce the team's chances in the final four. That's why a Markov chain is so.good at making predictions. It refined it's approach as it gets information.
In real use, Markov chains get much more sophisticated. So sophisticated that becomes hard to keep track of all the variables. That's where higher level math like *linear algebra* comes in.
In a *Hidden Markov Model*, you don't actually have to know how all the pieces fit together. You just need some good relationships:
- taller players do better
- players have to be healthy to play
- scoring early is important
Using *eignevectors* a mathematical approach can take a *system of related linear equations* and figure out which variables are *independent* of the rest. You do this by mathematically rearranging all the equations so that the few that dominate the rest fall out.
- taller players do better and the early scoring for this team is directly caused by their best player being tall. It's really only one variable at work here.
As the Markov chain gets updated, the most important variables might shift.
- Taller players do better but this team's tall player is injured so the height variable is no longer part of what contributes to their early scoring. | 33b42b38-4ce9-465a-9ba4-e6242defba93 |
2y4ahm | why is the holocaust so much more popular than other historical genocides? | Aside from having one of the highest death tolls (only the Congolese occupation has a higher average-estimate death toll), it receives attention partly because it was a new type of event. The word 'genocide' itself was only coined in 1944 to try and name what the Nazis had done.
The Holocaust was a planned, deliberate attempt to completely wipe a race of people from the Earth, domestically and internationally, executed in a large-scale industrial fashion using all the tools of a developed 20th-century nation, and had the fascists not been stopped by war, they would have seen it through to completion.
That's new. That hadn't happened before. That's why it's so studied. Sure, there had been lots of other mass killings and racist crimes of humanity -- but they weren't like the Holocaust. They usually fell into two categories: brutal massacres committed by invading armies (as seen in Mongol campaigns) and horrendously exploitative colonialism (as seen in the Congo Free State).
The fact that Nazi Germany was a modern highly-developed nation also factors into it, I'm sure; it has a larger, more devastating impact to think of a modern educated developed country doing this, compared to say, the tyrant King Leopold and his absolute monarchy generations and generations ago. Likewise, Eurocentric views dominated as a matter of policy until very recently, so of course an event occurring in the heart of 20th century Europe has more shock value than some old business off on the (gasp) Dark Continent. Then there's the fact that we have huge amounts of recorded testimony, photographic evidence, video evidence, etc of the Holocaust. There are a lot of factors. | 86b86cf1-356e-4c79-9682-882090c33855 |
2besa5 | Why does my stationary leg hurt when I ride a skateboard? | More to the point, it is almost like doing a one legged squat. In addition to holding all your weight up, you are lowering yourself several inches (with one leg) each time you kick/push with the other leg.
I have a adult sized kick scooter where I experience the same thing. I could kick all day, but switch legs often because of the fatigue in the leg on the board. | 5fe55295-1965-420e-9aa2-4f2eda36a606 |
1upfk4 | What is the significance of the MPAA joining the W3C? | The World Wide Web Consortium (W3C) defines the specifications of the web. It's largely an organization of technology companies and publishers trying to agree on standards to move the technology forward.
As streaming audio/video is being increasingly standardized (in things like HTML5), the MPAA naturally would like to have early input into how it's works - not unlike how Bloomberg cares about RSS.
The controversy is largely because MPAA has for years fought the industry rather than worked with it, so most people perceive it as a way for the MPAA to slow down tech or make a fuss about DRM (as that's how they've behaved before) rather than a step in the right direction to offer good solutions.
What does that mean to the average Joe?
Well, for years there wasn't a standardized way to do video on the web. So Flash emerged, and Flash sucked. For years Adobe had a monopoly on it, and it's the reason a lot of early video didn't play on your iPhone (because it was an Adobe-owned format that they couldn't come to agreement on).
HTML5 streaming video (which the W3 standardized the specification of) fixed that by pushing it as a standard that every vendor could implement on largely their own.
Lots of technology like that will emerge and evolve over the coming years. How it affects the day-to-day for the non engineer in the industry is usually non-obvious (like the above example).
It simply means the MPAA will be present at a few tech meetings earlier than they have in the past. If you're an optimist, that means that they've learned their lesson somewhat and will try to work with the industry instead of fighting it. If you're a pessimist, it means they're going to make a short-sighted fusses that slow down the technology evolving. | 41f2fe7c-c1fb-4142-b74c-f0f321e871d8 |
4ntuke | Why does electricity "want" to be grounded. If there was a bigger planet then Earth here would electricity jump to it instead ? | The more general rule is that a system will tend to minimize its potential energy. For example, a ball on the top of a hill "wants" to roll down to minimize its gravitational potential energy. Similarly, a circuit "wants" to minimize its electrical potential energy, or voltage (technically voltage is electric potential energy per charge aka electric potential). *Ground* is defined as voltage=0, so a circuit being grounded is like the ball reaching the bottom of the hill. | 13d2e4bd-a441-4e5a-b8f5-84153ceacefb |
6utv9k | What is that nasty gunky substance in your mouth after waking up? What is the cause of it and is that the reason we must brush our teeth in the morning? | If you're not brushing your teeth well enough before you go to bed, it may be plaque. But if you are, it might just be the inner lining of your mouth shedding and congealing nastily due to the nighttime dryness of your mouth.
Your mucus membranes shed even faster than the rest of your skin. | 10a40310-63bb-48c9-984f-e32fffa43493 |
447zxb | Who REALLY foots the bill when a corporation goes bankrupt? The unpaid bills? | Whoever those bills are owed to, as the corporation does not have to pay them, so the debtors are shit outta luck on recouping that money. | 8f3ecea3-f756-48fb-ae56-4cfa2b0e5365 |
1n72sj | Why are textbooks so expensive? | Because only a small number are printed. If you print a million of something, the costs are divided across that large number and it can be cheaper. Print only 10,000 and the "fixed" costs are now divided across 1/100 the number of books. | d0353db9-1459-46f2-aa47-932f94edef0c |
8ezdug | Why is it when a show or movie has subtitles, we can’t help but read them? | Two things
1. Remember how you spent the first several years of your life sitting in rooms reading stuff all day? and then you go to work and read stuff all day?, etc, etc. Your brain does \- so when it sees words, even without you telling it to, it goes "ooh, I know what to do here" and reads them. The brain just gets conditioned to read words that it becomes \(somewhat\) automatic. You can notice yourself doing this in other parts of your life too where you will automatically read stuff even if you weren't specifically trying to focus on it \(e.g. signs on the side of the road\)
2. Often in movies where there's dialogue being exchanged between two characters there's not that much else going on but the subtitles are changing, so they are actually the most "interesting" thing happening. Next time your watching a movie with subtitled but not trying to pay attention to the subtitles pay attention to when you pay attention to them \(as weird as that sounds\) and you'll probably notice that you're more likely to notice what the subtitles are doing when there isn't much else going on than you are during the action sequences. | 458bb81f-d11d-4b07-ab9f-fc4c107e5602 |
49d8wi | Why do we have to pay for internet? And why is there a limit? | You're not paying for "the internet". You're paying for a company to *connect* you to the internet. They build the infrastructure, they run a lot of very high-end, very specialised equipment, and they spent a *lot* of money on it. They're not going to let you use those for free. | 9082857c-513a-496b-8bc3-27b22a5cf32f |
513two | What and how can start a natural bushfire? | Lighting mainly. When a volcano is conveniently located that will suffice. Plus if you have a decent damp pile of plant matter as it decays it can just get hot enough to burn. | 647514a7-285f-4cf3-8c17-619938a604a1 |
3gh7zc | Why must we let a steak "rest" for best flavor, but that just makes it cold? | You just need to let it rest for 5-10 minutes before cutting into it. When you cut it right away after removing from heat, you will notice the plate will fill with liquid. That liquid is full of flavor that the steak loses. | 8e9137cd-02a4-4a55-84b7-91778135db70 |
1j9a6f | How do food companies determine the expiration date for a product? | It is calculated by measuring the rates of breakdown under less than ideal storage conditions. With ice cream, the limiting factor is likely to be the time it takes for ice crystals to grow, as well as the oxidation of some fats, degrading the taste and texture of the product. Because of this, it is likely to be called a 'Best Before' than an 'Expiry' date.
All of this is very complex, but is reduced to a certain number of days, from which is subtracted a safety margin, again carefully calculated. This is added to the date of production to give an expiry date.
If it has been in your properly functioning freezer, and is a few days over, then chow down and enjoy. | ee33de34-32b4-4482-b58c-001e8d24f748 |
5mp9n4 | Why can you hear the voices in the apartment above you so easily, but not the voices in the apartment below you? | Because sound travels through the solid medium ( the floor slab). On the floor above, people are directly in contact with the surface; while on the floor below, you're only depending on the noise traveling through air and noise traveling in air is divided into reflected, absorbed and transferred, major percentage of which, is reflected. | 9970ca08-4ed0-4385-a569-8ad9fa394560 |
3htk72 | If you were confined in a small space with limited oxygen that you were trying to conserve, would it be more efficient to take continuous short breaths, or fewer breaths while holding your breath for longer periods of time? | You would want to lower your metabolic rate. Decrease heart rate. Calm down. Take long deep breaths. Make each breath last as long as possible....... I think. | 310e483b-b2ce-428e-8f8b-8e135618b4e6 |
37y6zs | How comes different phone chargers take widely different time to charge the same phone,despite all being rated 5V 1A? | The usb standard originally allowed for only 500mA to be drawn per port. This isn't really enough for smartphones and especially power hungry tablets etc., so the manufacturers came up with a way for chargers to indicate they were willing to supply more power to the device. The device charging circuit can then draw more power than that safely - without that signaling the device could try to draw more than the charger/port can supply and possibly burn it out.
Sadly there were different methods chosen - some short together the data leads, some use different resistors between them or between them and the ground pin etc.
The wrong charger/cable with the wrong device won't step up to the higher current.
I've just bought a small gadget from dealextreme which sits in the usb port and tells you how much current is being drawn from it. My cables vary from 0.3 to 0.95A to the same device - I'm in the process of labeling them and exploring the various combinations of charger, cable and device.
Tl;Dr it's complicated. | 45f31bad-ba59-46a2-8bdc-a4801dec8a8e |
1wvyjj | Why is mace (pepper spray) illegal in the UK? | There is no such concept as "defensive weapon" in any of the UK legal systems. Anything carried with the sole or primary intent of causing injury upon another is always considered an offensive weapon in the UK.
Note that the perceived intent of usage is important. If you were carrying a baseball bat outside a town park at 11 o'clock on a Sunday morning you'd be highly unlikely to be stopped by the police. If you had the same bat outside the same park at 2am the police would almost certainly consider it an offensive weapon.
Also note that defending yourself in a threatening situation is perfectly legal in the UK, as long as you use "proportional force" and that you haven't pre-armed yourself with a weapon. | cfd6f078-1803-46a0-a403-6cd8fe36f16b |
3uymj8 | Can I take any antibacterial medicine for any bacterial infection? | To answer your questions: no, and yes.
Bacterial infections treated by antibiotics vary widely. There are gram negative and positive, cocci and bacilli and several other ways to isolate or classify organisms. A physician will order a culture/sensitivity test which takes several days to determine what cootie you're growing and what antibiotic it is most sensitive to. Antibiotic stewardship follows treating the infection with the least broad spectrum medicine available to avoid creating more resistant strains. Also remember the common cold is a virus which are not affected by antibiotics. | a814d7f2-110d-4e1d-bb0e-ae121cdeb62d |
65jb19 | What is the force that causes you to think of someone moments before they call or text you? | Coincidence, confirmation bias and faulty memory.
There are no special forces. Rather, sometimes when you happen to think of someone they will contact you soon after. More frequently when you happen to think of someone, they won't contact you at all. Human memories are fairly flawed. Some of us might think we are masters of remembering stuff, but really, we aren't. Maybe rough lines, but details? Nope. And our memories are quite easy to influence as well, both by others and by ourselves.
All of this leads to the situation where you are more likely to remember those times you were thinking of someone and they just happened to call you. That makes you believe someone is always calling you as you think of them (because you don't remember the more frequent times when they don't) and you confirm your bias with your flawed recollection.
Just grab a notepad and start marking down every time someone crosses your mind, even for a moment. Write down when these people call you. Do this for a week, and you'll quickly see that you think of people far more often than they call you, and them calling you is not related to you thinking about them. | d3bcce4d-86e1-4328-95fa-d0092074ddbc |
uhz3y | how rumble strips work | They provide step inputs to your suspension that can't be completely soaked up by the shock absorbers, causing the vehicle and its contents to vibrate at an audio frequency that most people are sensitive to.
Here is what the [US Federal Highway System](_URL_0_) has to say about them. | 3e523f66-f9d3-4357-9200-05ed1a01088c |
3863v8 | Why does the U.S. military use exciting action commercials and other fanfare for recruiting rather than just telling us what the threat is? | Why does Bud Light have commercials of a guy playing ping-pong with Arnold Schwarzenegger instead of advertising its price and alcoholic content? Like any other advertiser, the Army spends millions trying to find the best way to sell themselves. The simplest answer is likely the exciting action commercials are the result of a group of very intelligent people studying data and crafting a pitch they think will attract the largest group of people. As with any commercial reaching millions, the results tend to be generic and inoffensive.
There are many reasons I think they'd avoid a "Hitler is killing all these people" commercial:
* It's a complex situation. We're talking about a fifteen second commercial designed to grab your attention, not a WWII newsreel.
* A commercial focusing on the enemy subconsciously reinforces the danger of serving in the armed forces. The single biggest downside to joining the military is that you could end up dead, and they obviously want to avoid anything that could reinforce that idea.
* Hot-headed assholes yelling "Let's go kill us some ISIS!" is NOT what the military wants. The keywords they use instead (bravery, commitment, service, etc.) are the more important indicators of military success that they're looking for.
* Our enemy isn't exactly the most... politically correct. The White House [refuses to even use the term "radical Islam"](_URL_0_) when referring to people like the Charlie Hebdo murders, for fear of alienating American Muslims and Muslim allies. The armed forces are likewise strongly recruiting Arabic-speakers and Muslim-Americans, and angry faces with turbans on your commercials won't help. | 1f3238b7-753f-4501-a680-fc6a531b6e67 |
7qazx9 | What are the differences between the North and the South Pole? | The North Pole is in the middle of the water, usually covered by ice (less so nowadays because of climate change), and has polar bears, but no penguins.
The South Pole is on land (Antarctica) and has penguins, but no polar bears.
Also, the North Pole is in the Northern Hemisphere and the South Pole is in the Southern Hemisphere. | ac95e357-3033-4b31-a009-e6c5e8b6dcd0 |
3jsm8x | What exactly makes some genes dominant and others recessive? | I remember that this was explained on Ask Science a year ago (Don't know why I know about it, but eh...); here's the link to the answer given, as it's really nice: _URL_0_
To paraphrase the analogy:
Genes code for different things. Some genes code for different structural proteins. You can think of these genes as coding for bricks. Our "good" alleles (b) code for rectangular bricks, and bad alleles (B) code for spherical bricks. If you have one gene for each, you're going to be making both spherical bricks & rectangular bricks. But that's a problem - your building needs all rectangular bricks, and having some spheres and some rectangles doesn't build your building. You have loss of function, so that negative trait is dominant. (the bad allele B is the dominant one)
In contrast, if a gene codes for an enzyme, it's likely to be recessive. These are like building trucks. A good truck works, and a bad one doesn't work. But, if you have some good trucks (good alleles, T) and some bad trucks (bad alleles, t), you might just have enough good trucks in total to transport the material you need from one place to another. Thus, we say that the bad trait is "recessive", because you're not going to experience full loss of function unless you have two bad alleles (only the tt case shows total loss of function, so the good allele T is dominant over the bad one t). Now, you might have some negative effects, particularly if you need a lot of the enzyme, but it's not going to be a total loss for the most part, and you may well be able to function on a day-to-day basis without major issues. | db24f68d-3ab1-49fe-9795-c21373383a6d |