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28bvjw | Why are Pit Bulls a more dangerous and unpredictable dog compared to other breeds? | They're not. Unfortunately, a fairly large majority of pitbulls are located in lower-class, poverty stricken urban cities/neighborhoods. This could be because they have a large build compared to other breeds. But, because these dogs are usually trained to "protect" and "intimidate," it's just a case of classical conditioning. A pitbull pup is no more dangerous or unpredictable than a golden retriever pup. It's just a case of bad circumstance. | c91acf68-f722-4913-b5a0-d1346a334616 |
372yir | Why aren't we doing anything about the colossal amount of trash in the pacific ocean? | Because it isn't what people think.
The Pacific gyre is filled with plastic, it's a huge problem, but the plastic is millions of tiny pieces suspended in the water.
To 'do something' you'd have to filter billions of gallons of water without killing every living thing in it and then find some way to remove the plastic accumulation from the local biomass without again killing everything. | 3f8788a1-683a-4ab6-a179-8974919a6f18 |
5cpxqv | Why does smoking cigarettes make my hangover seem a thousand times worse? | EDIT2: I see I may have misunderstood the question. Perhaps OP was asking why smoking while hungover makes the hangover worse. Perhaps they were asking why smoking while drinking makes the hangover worse. I answered the second question. The answer to both is the same: unknown.
Doctor here. This is the type of question that invites a lot of speculation based on various popular myths about what causes a hangover. Since the process underlying a hangover itself is not well known, an explanation on why it would be exacerbated by nicotine is going to be even more speculative.
However I want to offer something more than just "nobody knows". One likely explanation could be explained by the phenomenon of the date rape drugs. In the emergency department it is not uncommon for young women and sometimes men to come in complaining that their drink was spiked. What we find after a toxicology screen is typically no evidence of any of the date rape drugs but rather a very large amount of alcohol. What happens is that people lose count of the number of drinks but they've had and when they are more intoxicated than they expect, they blame a date rape drug that never existed.
I expect a similar phenomenon is happening here. Simply put, the nights that involve both cigarettes and alcohol are probably nights with a greater amount of drinking or staying up later or partying harder in general. Could nicotine and alcohol have some synergistic effect leading to a greater hangover? Sure it's entirely possible. However this phenomenon is likely not well studied, well understood, and most importantly is likely far overshadowed by the social factors associated with combining the two as discussed above.
EDIT: there are only two papers on all of PubMed that result from search terms "nicotine alcohol hangover". One is totally irrelevant. The other is almost totally irrelevant. Here is a link to that second one: _URL_0_ . Terms "alcohol cigarettes hangover " produced one paper on marijuana, "ethanol cigarettes hangover" got no hits.
Point being, no real data. | 29f357a0-a879-440c-a4c9-88af56a24fb7 |
scbaz | Why gas stations promote that their gas is ethanol free. | We as humans figured out a way to turn corn into a fuel-additive. It's cheaper but our current internal-combustion engines aren't really built to effectively utilize it.
Like you're five...
You freakin' love some mac 'n' cheese and can eat it all day, every day, for every meal, and be fine.
Mac 'n' cheese is a bit expensive so Mom finds a way to mix in some 2% milk and not use as much cheese so she can save a few pennies.
Only, your stomach isn't used to 2% milk, so you occasionally have cramps. And the milk doesn't provide as much nutrition so you require just a little bit more of it.
EDIT: To angle this towards your original question: They're saying that their gas is better for your engine and not "corned down" with ethanol (which may damage your engine and not produce as much energy). | 1c41a116-8598-46ad-a1bd-15feb8ab037f |
231i2n | Why would the U.S. or its companies sell military technology it currently uses to other countries allies or potential adversaries? | Lets look at it this way. Israel, for example, is the US's ally, right? Generally speaking, the US and its allies have common goals and mutual interests, so Israel having superior American weapons means that they are better suited to pursue and/or defend their mutual interests.
Secondly, allegiances are generally pretty strong. It's rare that a country with strong vested interests turns coat and dumps their current ally, so the idea is that they are safe. That being said, not all allies are treated equally. While the US might form an allegiance with Ethiopia, it might send or sell retired obsolete (by our standards) military equipment, but it probably won't send F-35s for the reason you suggested, that it may be vulnerable to intelligence breaches or the ally changing.
Finally, allegiances are a tit for tat arrangement. Going back to Israel, they are firmly American allies, but its not always a smooth relationship. Lets say Israel is causing more problems on the Gaza Strip than normal. The US can say (privately) "We will withhold the next shipment of F16s until you guys take some heat off the strip." Or the other side, "Israel will continue to offer public support of American interests in North Korea, as long as you keep the planes coming." None of these analogies are perfect, but you get the idea. | 87e64cd6-2dbe-43cb-8563-2493cdeaed74 |
4darr0 | when resetting electronics such as a wireless router, why does the amount of time matter with regards to unplugging the device? | Most electronic devices have circuits built into them that "level out" the electrical current coming into it, to prevent the device from malfunctioning if there is a power surge or a sudden drop in mains voltage.
That circuit has some electrical elements called capacitors in it. (capacitors are basically tiny batteries) Those capacitors can keep a device running for a few seconds (or more), even if the power is unplugged. This is where the wait time comes in when unplugging: You have to wait for the capacitors to discharge, or you haven't really done anything by unplugging.
Very low power devices (or devices which can enter a "low power" state) can run for significant periods of time (several minutes) on leftover capacitor charge. | e7804cf5-78e8-428c-813c-68fd8c651116 |
2h7jnp | Why does a single repeating drip of water drive us crazy when a small trickle of water does not? | A trickle is a constant noise and is easy to cancel out. A drip is catching your attention every 5 seconds (with a 5 second drip frequency) because there is silence in between the drips. This makes it hard to focus on anything else which is more and more frustrating for each drip. | f83e02cc-560a-47fa-a307-587d6f1ed7bb |
2puzjx | Why do I feel sharp pains in my pelvis and ass when I see videos of people getting hurt? | I've tried to research this and not come up with much, but I've been searching for a sensation between my navel and solar plexus. | 4f6da323-5d2a-42eb-8d69-c0613efeb3fe |
1fe2sz | If I froze some ice at -10 degrees and another piece at -50 degrees, would the -10 melt faster because its less frozen? | It would melt sooner assuming they are both heated at the same rate, yes.
One piece of ice would need to absorb 10 degrees C of heat to start melting, and the other would need to absorb 50 degrees C of heat. | 5a8d9774-2518-4c86-9805-33cea15b1b5a |
5j17j3 | Why do we have that special attachment to our own bed? | It's because we spend fully one-third or more of our lives in it. We sleep in it almost every single night. When you see something or do something that often, it becomes familiar. when humans become familiar with something they grow to like it and the attachment often grows the longer it goes on. Think about the foods you loved as a kid. You probably are it a LOT, and that's one reason you love it, because you are it so often that it became familiar. It's the same way with your bed | f4db8205-e7ea-4bfd-9abd-817ead84ff1a |
3g4vsc | How can Donald Trump, a man who regularly makes obscene statements and engages in twitter insults, be at the forefront of Republican nominees running for president of the United States? | A large part of it is that Americans are very tired of politicians that pussy-foot around topics, pander to the political wind, and are percieved to be (rightly or wrongly) beholden to their campaign donors.
Trump is percieved to speak his mind honestly, and he's rich enough that he isn't dependant on campaign donations from special interest groups. This is refreshing compared to what Americans have come to typically expect from politicians that refuse to address issues directly and speak a thousand words without actually saying anything.
Note: I do not particularly support Trump, and several of his possitions conflict with my political values. This is meant as an explaination of my assessment of his appeal. | c30b3f21-9ecf-4794-93b9-b870ed1b1fca |
7l84zz | How does Switzerland's politically neutral stance work? What protects them from external threats? | 1st: money. During WWII they stored nazi gold and allied money.
2nd: it's a mountainous country with a militia-style army (in theory every man is in the army and has a weapon at home) and they have plans and preparations in case of war that would completely close off the country, everyone would evacuate to the mountainous regions and fight guerrilla style. Basically invading Switzerland would be extremely hard and costly for anyone and not really worth the trouble. | da9e3adb-4838-406e-84e5-5290c479c7bc |
2ml5po | What is a spider doing when it sits on the wall for an extended period of time? | In a parallel universe, on spidereddit: "What is a human doing when it sits in front of a screen for an extended period of time?". | 28c2cac5-613c-4659-8243-bdfa35aa40ea |
4ujqmt | Why are bus steering wheels (nearly) parallel to the ground whereas car steering wheels are (nearly) perpendicular to the ground? | Professional bus driver here. It has to do with the angle of the rod that connects the steering wheel to the tires. Since the bus driver is much more elevated and basically sits directly above the tires the steering wheel needs to point almost straight down in order to connect. The driver of a car sits behind his wheels and as a result, the steering wheel is at a different angle. Here are some diagrams to better explain it. The first one is a bus, the second is a car.
_URL_1_
_URL_0_
Side note: In most newer buses you can adjust the steering wheel to make it more like a car's. | b26f2c66-25e9-43fe-90a2-326cc31881aa |
2zhcwa | Why do black socks leave lint in between my toes but white socks don't? | Because you're white and the black lint shows up better | 67d1afd0-f6c9-4959-b90a-a41194e0acad |
3xxhco | What were the purposes of the Nazi concentration camps? | The original purpose of the concentration camp was to imprison the Nazis political enemies. This was not *quite* so fantastically despotic as it might appear; Germany had been rocked by violent demonstrations, street fighting, and violence between the revolutionary Communist Party supported by the USSR and right-wing militias. In fact, Germany's socialist party had previously declared martial law in Prussia, a state where they controlled the regional government, and were doing a pretty good job suppressing political enemies who were trying to subvert socialist rule with violence. So something had to be done to control political violence and radicalism in Germany; but the Nazi Party approached this in the most cynical way possible and actively framed all possible opponents as violent radicals and ended up putting all sorts of leftists, of any stripe, into prison camps along with violent criminals and other social undesirables. Then they added to that a number of extremist elements from within the Nazi party (basically, leaders of a paramilitary wing who the Nazis didn't need any more, because they now gave orders to the *real* military). Many of these labor leaders and Nazi "brownshirts" were just flat-out murdered, but the ones who were imprisoned really were just being warehoused. It's not like they couldn't kill whomever they wanted.
Subsequently, the Nazis added more and more people to the camps, eventually embracing all of the Nazis' bêtes noires. Political dissidents, religious dissidents, homosexuals, cultural degenerates, lazy people, Soviet POWs, whatever. Adding the Jews to the camps was, in itself, not spectacularly different from nastiness in other countries at the same time. For example, in 1941, the US bundled up all the US citizens of Japanese descent living on the West Coast and shipped them off to concentration camps in the Rockies. The official US rationale was that they were "the enemy within" and there was no way to be sure which of them were spies, collaborators, and secret saboteurs, so it was better to lock them all up just to be sure. The Nazis had always had the same ideology about the Jews.
The movement of Jews into concentration camps was accelerated as Nazi Germany faced more and more of a dilemma about housing (Allied night bombing destroyed far more civilian housing than anything else) and food. At first there was no specific plan to kill the Jews, although you know how these things go... the "concentration camp" was invented by the British, who figured out that if you herded lots of Boers (Dutch South Africans) into crowded, dirty camps and didn't feed them, then they would die like flies of infectious diseases. The first mass-killings of concentration camp inmates were probably of Soviet POWs. In 1942 the relevant Nazi administrators apparently came to the conclusion that, of all of the zany pre-war ideas for what would happen to Jews (send them to Madagascar, for example), the simplest solution was to kill them.
> Were they producing anything for the war effort? Slave labor essentially?
Yes, they were producing all kinds of things. The book *Schindler's Ark* is a semi-fictional account of one German businessman who got contracts to produce goods with Jewish labor, you can read it if you are interested.
> If so, why were so many people killed in droves when they could have aided the war?
There are three basic theories:
1. Nazis be crazy, yo
2. Intentional executions at the concentration camps were a small part of the total death toll; the major problem was lethal epidemics among the prisoners, especially as crowding increased and the available food and medicine decreased as the war got worse and worse for the Nazis
3. The Nazis didn't have enough food to feed their slaves anyway, so it was easier to work them into the ground and then shoot them. | f112309a-bce4-4045-b5c3-f3eeeeb84ded |
3q43o8 | Why does it feel like your heart is in your throat when you're nervous/anxious? | You have major veins and arteries with blood pumping to and from the heart in your neck. What you're feeling is the increased blood pressure from an increase of blood flowing through those veins and arteries in your neck. | 1829500b-9fdc-4c2e-a3be-9f52be9ac607 |
17su5y | Why is it that when I fart while wearing pants and sitting down it feels like there is a bubble moving between my jeans and skin? | My (educated) guess is that it is an actual bubble. Fabric can contain gasses (not very well, but some of it), so it might very well be that a bubble of gas lifts the fabric from your skin and moves until it comes to a place where it can freely escape into the air and poison you enemies. | dbd90417-6aea-4f13-a14a-eaa2ddbbb1ff |
1sbxfm | Why have Washington and Colorado not released people imprisoned for pot? | Because those people committed crimes. Just because something is legal today does not suddenly make them not-illegal when the crime was committed.
The flip side of this is that you can do something that's legal today and not be charged when they change the law next week. | 9372a827-8e70-4438-aec7-2262d3387017 |
5qxs73 | (Conflicting info online) What genes determine eye color? Can a blue and a brown make a blue? Brown and a brown make a blue? | In both cases, yes.
The brown-eyed gene is dominant while the blue-eyed gene is recessive.
A person with brown eyes can have either one brown-eyed gene and one blue-eyed gene, or two brown-eyed genes.
A person with blue eyes has to have two blue-eyed genes.
So a blue-eyed person and a brown-eyed person who happens to be of the "blue-eyed gene and brown-eyed gene" variety can produce a blue-eyed baby.
Two brown-eyed people who both happen to be of the "blue-eyed gene and brown-eyed gene" variety can also produce a blue-eyed baby. | 3080b34e-6cbf-42af-8d1c-93b1fd3b0345 |
4t5iw4 | Why can small creatures such as Ants lift things much larger than themselves? | There's an mathematical law that pops up in nature called the [square-cube law]( _URL_0_) which simply states that as an object gets bigger, its volume increases faster than its surface area by a factor of a cube compared to a factor of a square.
This is relevant to biomechanics because muscles get stronger according to their cross sectional area, which grows with the square of the radius of the muscle. The volume (therefore weight) of the muscle (and the rest of the animal) grows with the cube of the radius of the animal. This means smaller muscles are proportionally stronger per unit weight than larger muscles, because the volume shrinks faster than the cross sectional area.
Other small animals use hydraulic pressure and not muscles to move, but the explanation is the same. | 61a185ad-4824-40b8-aefd-67361fc8d9d6 |
366efk | When you look at someone welding, it hurts your eyes. Why is it that when you look at a video of someone welding, it doesn't hurt your eyes? | Welding torches emit ultraviolet and infrared light, which can hurt the eyes. Since cameras are only designed to pick up visible light, and monitors are only built to display visible light, UV and IR don't get projected by the video. | b2e41f36-2dbf-47b1-b84e-8e2329f363f4 |
1n67rn | Why are rocket scientists considered some of the smartest people? | The USA went through a period where we were racing with the Soviet Union to make milestones in space exploration. During that time there was a huge amount of government investment and public expectation toward the field, and this attracted the best of the best in many fields toward constructing the technological marvels that space rockets are. A rocket scientist would need both advanced education in engineering and physics, and was afforded generous salaries and social benefits for their contribution to the space race effort. This reality of such a person's value to society fueled the birth of the saying. | 61a300fc-01fd-4ac7-92e7-c6b303101393 |
6u26vf | Why are there no hreen, blue, true red or puple mammals? All other animals (insects, reptiles, fish, birds, etc.) come in a rainbow of colors; why are mammals so limited? | It's our hair that colors almost every mammal, and hair can only come in so many colors: browns, reds, yellows.
Note that "blue" in most animals is structural, not pigmented color. The feather/wing/scale is actually microscopically shaped so that it looks blue, unlike our skin/hair which is pigmented. You can find neat pictures of pretty blue butterfly wings backlit, showing they're actually pigmented brown like a drab moth wing. Blue is a really rare color in nature.
Green is hard, too. Plants do it just fine but we don't grow chlorophyll. Green snakes and lizards are actually structurally blue with yellow pigment. They turn blue when they die and the yellow pigment breaks down, leaving only the structural blue.
Straight red is also hard. Cardinals and flamingos are only reddish from their diet. Koi can't turn gold if they don't eat the right algae.
Purple is also rare (who wants to be purple?), but again, some red pigment and blue sctructural trickery can make it.
Hair is not shaped well for sctructural coloring. Unlike a scale or feather or insect wing, it's not patterned and orderly enough for the structural blue trick to work well. But even then, you can find people with natural, very black hair that has a bluish sheen to it, and that's why. For the most part, though, we're stuck with our pigmented colors. | 15bd148b-a099-472f-a97b-2448144f41ff |
3c9i26 | The existence of North Korea | NK is still a place because it is a country. China hasn't taken them over, because Russia and China have diplomatic ties with NK. They may not be good, but there is ties. As others have said, they gain nothing from taking over NK. | e0bdcde1-f393-4ee6-bc67-b209856d3823 |
46m0s6 | Why buying a new car is a negotiable price instead of being a fixed price | Because in any business, if you're fighting for one dollar and ended up losing ten because of it, you'll get fired.
So they're not gonna lose ten-whatever thousand just to save one or two.
With cars, there's a minimum price that they have to sell at (which is never the advertised price). The sales person then has that margin of trying to get the biggest profit possible with that car, and even if you go for barter the fuck outta the car and manages to make a massive saving, they're still making the intended profit.
You're not actually losing them any money by negotiating, you're just doing yourself a favour. | 0e7cea0d-792b-4246-8b94-149931ec57b4 |
7ocqh5 | Does the earth 'leak' into space? | it does, solar winds strip little bits of our atmosphere away, we lose a few tons every day. some is replaced by micro comets/asteroids.
net net its relatively small, and does not pose a threat to us on geological time scales (IE wont cause appreciable harm before the sun eats us in 10 billion years) | 69139546-362d-4c5d-9352-91bd45403ce9 |
2etcvy | why can't nations conquer other nations like in the past. | Before the Napoleonic Wars, total conquest of another region was relatively rare. Only a few ancient and medieval powers were capable of it. Rome, Byzantium, The Arabic caliphs and the Turks, Charlemagne, Genghis and Kubilai Kahn, and various chinese dynasties. It took a very long time, like 20+ years, and the cost in resources was vast. "limited war" was the norm, because armies are so expensive. With the dawning of the industrial age, and the invention of "total war", the process became moderately easier. This is why you see massive empires being dreamed up relatively often as soon as industrialization becomes realized. Larger armies and more weapons became cheaper. Total war is incredibly destructive, and its ultimate expression, nuclear weapons, are so much so that they are unusable in any realistic conflict where any party hopes to gain something. In the strictest sense, nuclear weapons mean that any military force that has massive territorial ambitions runs into the problem of "mutually assured destruction." So what we've seen then is a return to the more pragmatic forms of limited war, where one country might bite off a province or two, or acquire maritime rights or move the border a few hundred yards, but anything more than that becomes problematic. Complicated networks of alliances and "nuclear umbrellas" don't make things any easier either. When working out the diplomatic consequences of who can invade who, you have to calculate who their allies are and what plausible deterrent they have. Also, [nations](_URL_1_) are not inherently belligerent. A nation refers to a large group of people who share a common language, culture, ethnicity, descent, or history. What you are referring to, I believe, is an [empire](_URL_0_). Worldwide media culture is nationalistic in nature. That is why you see such sensitivity about countries being conquered, because the media supports such ideas as national determination, and is very much opposed to the forming of empires.
TL;DR: Nukes, groups of alliances, and nationalism. | bfe478d6-9fc8-4c3a-a7de-d35eb6eb8cde |
88imy1 | Why does the cold cause your teeth to chatter? | It's your body shaking to attempt to make you warmer, the teeth chattering is just a side effect of the shaking | 18facc38-53e4-4c3d-b3ee-71badc196fbb |
5fu2ti | What causes your body to feel different types of pain? From toothache to paper cut to sunburn, why does the physical sensation vary so widely? | Your brain is responsible for different types of pain (throbbing pain, sharp etc.) Your brain 'knows' where the pain is coming from and associates it accordingly. Its a useful feature to have because if you say, get scratched by an overzealous cat across the face, you need to be able to differentiate the pain to know what is hurt. If pain was just general, you wouldn't be able to differentiate what was broken, and possibly miss important stuff to treat.
The other variable is the strength of the signal.
A broken leg hurts worse than a paper cute because more pain nerves got activated in the accident, you brain interprets that to mean more sensation of pain. Those 'levels' of pain is your body's way of telling you how 'bad' your injury is (granted it is subjective but it works). | e38f4ec0-20ac-4d78-aca3-0b5e54c0e2ad |
6yu33r | How does Canada have access to US citizens criminal records? | Your criminal record is public information in the United States, barring circumstances like being a minor at the time or some kind of conditions on expunging it. It's not just Canada that can see it, anyone can see it if they ask. | 9717ac7f-9d12-4a7e-8c97-e5a0139109c6 |
1danvn | why rappers like soulja boy who are awful at rapping are still rich off of one hit wonders? | The same reason movies like Transformers are made
Basically, record companies need to hedge their bets. Now, all record companies have people in them interested in producing quality music but they still need to return consistent profits. It's very hard to find high quality acts that consistently, because generally their music takes a longer time to produce and they are harder to find but most importantly, they only appeal to a particular niche market.
Someone like Soulja Boy can make music that, although very few people actually think is good music, a lot of people can listen too. Like McDonalds, it appeals to everyone but not particularly to anyone. This makes it ideal music for large nightclubs and any other place with a large group of people with varied music tastes.
This is why Baauer is signed to the same label as Zebra Katz and Duck Sauce to the same label as Action Bronson. Every label needs people on it who can make music that everyone finds tolerable at a party | 2229c292-f3ff-4bdc-8366-7f16914c6ef7 |
1orpz7 | Why do i have to cough when i'm cleaning my ears? | Its because the two areas associated with the sensations are so so close together in the brain that ower-sensation can trigger the other. It will take a few seconds of cleaning before the cough is stimulated. Not everybody has this, but another common example is people sneezing when the pluck their eyebrows. The area associated with the pain sensation of hair plucking is right next to the sneezing mechanism, and so it sometimes triggers a sneeze! | 197c793a-3c78-4e94-a0a0-7de7a0fb694d |
7tu49j | Colombia still produces hundreds of tons of cocaine each year, why aren't there cartels in the country like when the Cali and Medellin were big in the 80's and 90's? And if there aren't big cartels, who is moving all those drugs out of the country? | I know that the US gives Colombia a lot of money to shut down cartels before they become powerful...and they are pushed out of major cities and into the jungle. Its kind of like a win win. They get major cities back for tourism and the production of drugs is out of sight out of mind in the jungle somewhere. Also a lot of cartels moved to neighboring countries...ie Peru.. | e6abcc20-7b1d-4275-a7a6-9a52c4f3f648 |
3zem67 | What are saccades, and why do eyes need them? | A saccade is a quick, jerky, near-instant movement of the eye. The speed can't be controlled; the muscles controlling the eye move as fast as they can.
One popular suggestion for the necessity of the saccade is that the central part of the retina, called the fovea, that provides the clearest, sharpest vision, is very very small. By jerking the eye from point to point to point, the brain can build up a map of the areas the fovea's passed over and thereby get a very detailed picture of what it's seeing. | 30c3e8a1-cb08-4346-ae7d-94356bc24ff8 |
ohnh9 | What is the connection between Thai and Chinese? | Regarding the cultural closeness of China and Thailand, as [this Wikipedia article] (_URL_0_) notes, a significant portion of Thai people are ethnic Chinese, and they are especially influential in business and politics.
So a Thai immigrant to the U.S. could very well be a third-generation Chinese, and if that person were to start a Thai restaurant, adding Chinese to the menu would be very easy, just consult family recipes handed down from China.
I truthfully think the reason you see them together is simpler, though. Much of Thai cuisine does in fact appear similar to southern Chinese cuisine (which is the kind most familiar to Americans): stir-fried meat and vegetables with lots of seasoning and chili peppers. And the average American wouldn't know the difference, so the restaurant can just make food that's kind of Chinese, change one ingredient, and call it kind of Thai.
I used to live in Seattle, and I never saw any mixed Thai/Chinese restaurants. Seattleites do know the difference :) | f0f95111-4d29-43fb-aa65-d23a8aeedceb |
1lem4c | How does a barcode work? | You know how Morse Code is a series of short signals, long signals, and periods of silence that represent letters?
Barcodes work on the same principle, only on the visual spectrum and with numbers. The lines you see in the barcode represent a numerical code. When the scanner sees those lines, it can figure out the numerical code based on how wide the lines are and how often there is white space. It then sends that code to a database somewhere, which knows what items have that code. The database then return that items to the cashier's register. | 421b988a-f8a1-4c61-9cd3-9ede70e42143 |
1ig87u | Why is 1080p advertised as "full hd" when there are much higher resolutions? | Because 1080p is what is considered high definition. 4k is considered Ultra HD. It's just a term used. | f2aa63a1-f127-49a6-8047-c714b98ea9d0 |
6jh6ks | How did Oasis become so popular in the'90s, and why aren't they as Iconic as Nirvana? | They had catchy, well written tunes.... for one album. Their follow up albums got worse and worse and the Gallagher brothers were notorious for not getting along with others or even each other. They even fought on stage. What they were not, however, is ground breaking. They sounded like an update of the Beatles.
Nirvana, on the other hand, were original. They produced music unlike anything else, over multiple albums. Also, there is something about dying young that tends to make musicians iconic. | a0556755-d1ec-4e58-bd93-30a24669afe1 |
8umvk7 | How are people able to feel how wet an object is through latex or vinyl gloves? | The most immediate giveaways would be the sudden temperature change, as well as reduced air pressure within the glove (glove gets tighter since the air pockets in the glove are getting pushed out) | 45e3bcb2-c837-4a7c-a5ea-bc6cd784f45f |
3m5nn3 | Why do we laugh when being tickled when it's not enjoyable whatsoever? | As with most things biological, there is a tremendous amount of guess-work required to come up with a meaningful answer.
There are many theories as to why we are ticklish and why we respond the way we do to it. The most compelling to me is the theory that tickling is related to play-fighting. The young of many social animals participate in play fighting where they will attack each other without the intent of causing serious harm. The human behavior of tickling seems to map very well to this, forcing the person being attacked to respond in a way which appears to be happy, and thus not distressing to the attacker. Children generally like some amount of tickling, but this fades over time at about the same time that 'play' of this sort gives way to other interactions. | 179f41c7-e743-4740-8f1d-97f9a2d787c9 |
1eun2n | Does the car A.C. Use gas or electric to run, and how does it affect gas mileage specifically? | It doesn't directly use gas *or* electric.
There's a pulley in the front of the engine. The air conditioning is turned by a belt that connects it to the pulley.
When the air conditioning is switched on, it's pretty difficult to turn the air conditioning unit. And since this unit is connected to the engine by the belt, the engine has to do the work of turning the air conditioning. It gives the engine more load.
This is similar to, for example, going uphill - another situation which puts the engine under more load. Either the engine (and car) will slow down, or you need to press the accelerator (gas pedal) more and use more gas to maintain your speed. | 87ba552f-4307-4ee9-aadd-600ad08468e6 |
4yppie | Why we need to become unconscious in order to sleep? | There are a few animals that are capable of remaining conscious while sleeping, such as dolphins. This is a phenomenon known as [unihemispheric sleep](_URL_0_), in which one half of the brain is sleeping at a given time.
As to why humans did not evolve to be unihemispheric sleepers, it is likely that the requirements to do so would detract from our other abilities. Our brains are set up in a way that the activation of both the left and right hemispheres are required to perform most tasks. Patients who have undergone a [corpus callosotomy](_URL_1_), a surgical procedure that severs the connection between these two halfs, often experience difficulties with tasks that require synchronization of both sides of the body (ex. tying shoelaces).
So likely, even if humans could become unihemispheric sleepers, we would not be able to perform any useful tasks. If we do want to be unihemispheric sleepers while keeping all of our current functionality, we would need redundant areas of the brain, which would be a big investment.
From an evolutionary standpoint, unihemispheric sleep is most useful to animals that must be constantly on the move (ie. long migrations, swimming mammals that need to surface, etc.) and are capable of maintaining this constant physical activity. Humans have no such requirements (since we can rest safely in shelters), nor the ability to do so (since gathering the required calories would have been hard for hunter gatherers). Therefore, our brains changed to increase our cognitive abilities, rather than our sleeping abilities. | dc848075-653a-48e3-8a1b-35944e0ff923 |
6jqv4t | How do loading bars know how far along a download is? | When you begin a download, it creates a "box" that says there is a specific amount space that the file will be contained in. As pieces in the box fill in, the box says "hey, I currently have been filled with X number of the Y required pieces." | 85febe6b-ef03-4269-bd16-6ef180b4c6a1 |
5e73nd | Why do bands bring have their own speakers and amplifiers if everything is just run through the arena's PA system? | Like their guitar amps and stuff? A guitar amp does a whole lot more to influence the actual sound and tone than the PA. A guitarist's amp is pretty integral to his whole sound, so he'll want it to be consistent, and he'll want control over it. Then the venue will put a mic on his amp to connect it to the PA. | e2399b94-9b02-44e8-943e-385025b973f0 |
10n8gx | In space, it always seems that we are shown traveling on a 2D plane. What happens if you leave Earth and go straight "Up" or "Down"? | Our planets are all mostly on the same plane, which is nicely convenient for illustration purposes. If you go any other direction, it's pretty darn empty. And it will take a while to run into the [Oort cloud](_URL_0_). Beyond that is way more empty before another solar system. | e929b891-cae9-4dde-9ca9-1dfe4cb807ad |
5rfh5l | how do we know how far away something is in lightyears? | Well lightyears is a unit of distance just like miles or kilometres. So if you can calculate the distance to a star you can display that distance in miles, kilometres or lightyears.
Now I'm not sure if you ask how we know what a lightyear is or how to can calculate the distance to a star.
For the first one, there is several experiment that was done starting in the 17th to estimate the speed. The first estimate was more than 20% off, but as we get better measurement technology we got a pretty good idea of the exact speed. After you have the speed in m/s you just need to multiply that number by the number of second in a year.
For the second question, how can we know the distance. There is different method. The first one is parallax. Look at one object and close you right eye. Then open the right and close the left rapidly. Do you see the object moving left and right? What happen is that you two eyes are not at the same position so they see the object at different angle. With a lot of complicated math that I couldn't do tbh, you can use the angle between the two image and the distance between your two eyes to calculate the distance between your eyes and the object. Now the longer the distance between your eyes, the more angle it will have. The longer the distance between your eyes and the object, the smaller the angle will be. So you want a good ratio between these two distance otherwise the angle will be too small to measure. Our eyes are way too close to measure a star. But the earth move a LOT during the year. So you can look at a start at one point during the year and then look at it again 6 months later and then you gonna be able to measure the angle and the distance between to the star. Now, you can guess that if you keep looking at star further and further away the angle will keep getting smaller and some star are so far away than we can't longer use that method. There is other method at this point, but parallax is the one use for most star that are relatively close to us. | a58f1e43-d41f-498f-9e87-d41f0bd6bea6 |
8mc29m | Why is the ocean water so clear in places like the Caribbean but not at US beaches? | Tropical waters like those in the Caribbean are warm, clear, and completely devoid of nutrients. This is why life clusters around reefs, a lot of creatures eat the plankton and algae that grows on the coral, they provide food for the area
The waters up north are cold, dark, dirty, and full of nutrients! The darkness is partially from dirt/mud but a large part is all the algae, plankton, and krill. These nutrient rich waters support a wide variety of animals and many animals will go to these dark waters to feed and fatten up during the summer and then return to the warm clear waters to give birth and raise their young | 810fdcc1-e4ab-4b8b-99d2-43c79005c7de |
211ndj | What makes someone a "light sleeper" vs a "heavy sleeper" and are there ways to change it around? | It's just a matter of habit. This is why you're supposed to have plenty of loud noises (vacuum, TV, conversations, etc) while your baby is sleeping, so it gets used to those noises and you don't have to worry about waking it. These habits are started as a baby by your parents, and they are extremely difficult - but not impossible - to change, once you're older.
To go from heavy sleeper to light sleeper, you must sleep in pristine, silent locations for probably several months to get your subconscious mind to get used to the silence.
To go from light to heavy, sleep with a quiet, but random sound playing, first, such as a TV on very low volume. Over the course of weeks, slowly increase the volume and graduate from calming things like music up to more chaotic things like conversation and eventually something with sudden noises, like an action movie. Eventually, your subconscious mind will learn that random noises are going to happen throughout the night, and it will just ignore them. | c0890362-92bb-474d-8367-501f33b66e6b |
75m5l2 | Why have newspaper comics gotten so abysmal these days? | Several factors are at play.
First, you're older, so you've developed a taste. You might recall loving Garfield as a kid, but now you read recent strips and it's dull and bland. But if you went back and read strips that were published when you were a child, you would find them equally dull.
Second, the authors change over time. They might come to view their comics as a metaphorical prison for their imagination. They might develop some sort of mental deterioration, as with Terry Pratchett.
Finally, external conditions might change that reduce their ability to do their work, as with Tom Lehrer (who, when he produced music, wanted to satirize politicians, but he stopped because today he instead wants to punch them). | 08acdd33-7288-4843-b0ba-a8d9a0867deb |
19xppi | How is it that I get so car sick when I try to read or write in the car when I'm otherwise fine? | Reading and writing requires intense visual focus. Your eyes home in on the paper, and the visual part of your brain kind of stops paying attention to anything in your peripheral vision.
However, if you're in a car, your inner ears are telling your brain "hey, I'm moving all over the place". But your eyes are telling your brain "nothing's moving, you're just reading a book". Your brain, receiving these two conflicting pieces of information, decides that it has been poisoned and makes you headachey/nauseous so you can vomit the poison back up.
True Story. | 627c392e-c079-4c18-9323-5a1cf6cda7a8 |
2p3ovu | Why is cheese sometimes crunchy/gritty? And what causes that texture? | The crunchiness is caused by crystals of various substances that form as the cheese dries. They start out dissolved in water in the cheese, but as the water evaporates, they start to crystallize. Usually, the crystals are made of calcium lactate. But sometimes, for some cheeses, there are crystals of amino acids like tyrosine, leucine, or isoleucine.
Fun fact: tyrosine is named after cheese. *Tyros* is Greek for cheese. Tyrosine was first discovered in the protein casein, found in cheese, by Justus von Liebig. | fac71075-1de3-40dd-bb04-162aa42bf2e9 |
32a9fp | If a MLB pitcher were to hit a player in the head, and that player have life suffering injuries, would the pitcher be in trouble? | Unless it was intentional, no. All the players signed legal waivers when they sign their contracts. | 01a61bf7-0de5-4203-b749-84c3e7da8efa |
1hdhft | Guantanamo Bay | It's a US Military base slash terrorist prison in Cuba. We jail terrorists there because they are not subject to US laws and do not have the right to a lawyer, phone call, speedy trial, know charges against etc etc.
Someone once told me another reason we keep terrorists off US soil is because the terrorists would become naturalized US citizens after a certain period of time. Not sure if that is true. | 67f3da28-ed4c-471b-a87a-726ba5092b4f |
5yogqd | If a joint cracking is a result of gases in the joint popping, how can I crack the same joint multiple times? | imagine you have a balloon and cracking a joint is like opening the balloons mouth for 1 second. If you have more fluid in your joints than one moment of release from a single crack, more will come out on subsequent ones. you may notice how they get progressively less powerful as the crack count continuously goes up | 1787cb3e-b9b9-4bb8-afb6-1df64b388209 |
82vzbi | Why or how do fires make sound? More specifically 'roar' ? | Hot air rises, and the fire heats the surrounding air unevenly, causing increased turbulent air flow around the fire that we can hear as sound. | f25cc1d8-e43c-48f5-b6b2-81dfb2d1dc15 |
2vouxs | The phases of the moon and their rise and set times. | The moon orbits and rotates around the earth in the same way as the earth orbits and rotates around the sun. Because the moon orbits the earth at a different rate that the earth rotates it causes the moon to rise and set at different times of the day
The phases of the moon are also due to its orbit. The part of the moon that you see is being illuminated by the sun. As the moon orbits earth, the side that is facing the earth stays the same( because the moon rotates at just the right speed to counteract its orbit so we only see one side of the moon) but the side facing the sun changes and completes one full cycle approximately every month. | 2f2928b9-db09-4cd4-a52a-383a9c8ebbdf |
2fzug2 | Is there any Virus which infects Apple products?Why is there such a big problem with windows and hardly any problem with the mac when it comes to bugs? | Yes, there has been malware for Apple products including OSX. Windows gets targeted more because it has a far larger market share. I haven't had significantly more bugs on a Windows device than I have on OSX. I haven't seen a BSoD since XP was the latest Windows OS, but I did see a kernel panic on OSX (So basically the equivalent) just a few months ago. | a4b27766-ecda-4d7a-994b-e47ed9a9a561 |
8j990v | Do birds stop for rests after flying for long periods of time? | It depends on the bird. Most birds do stop to rest, but birds like swifts, terns, and albatrosses can stay in the air for weeks or months at a time, usually by gliding on air currents. One benefit is that lets them conserve energy. | 8963a24f-ade3-4476-bebd-3782d88d22a7 |
71eygw | Stress is implicated in a great number of health problems today, things must of been pretty stressful for our early ancestors, why are our bodies still not able to deal with stress? | There's a big difference between acute stress and chronic stress. Life was not as stressful as you have been led to believe. Most anthropologists estimate that hunter-gatherers worked a lot less and had more leisure time than modern humans. The stress response is adaptive for dealing with short term threats in the moment, like a fight or a predator. It's not very helpful for "threats" that never go away, like debt. | b07e90f1-8b0d-40c2-befe-9643855fbfd4 |
2coae8 | Why auto makers dropped the frameless doors? | Because they really didn't work too well. It was too hard to build a seal between the car frame and the glass, that worked well when closing the door, while allowing the window to slide up and down. Because you couldn't hold the glass in a channel, the window gets pulled away from the seal at high speed, unless you design it to push tightly against the seal, which makes the door hard to close and makes the window-winder mechanism stiff.
The door-window seal has to do different things to the door-car seal. Trying to make one seal do both meant that both things were done poorly. | 536504cd-36f5-436b-bccf-4bb02c7f1b38 |
591med | is it true that if one sits too close to a television it will affect your vision after a certain amount time? | It MAY cause eye strain which could be a temporary annoyance, or cause a headache. But no long term damage can/will come of it. Simply put, your parents said that because if you were to close to the TV, it makes it harder for others to see. | dd68297a-e21e-456e-b232-27cd12947937 |
1h8bdg | Australia is a relatively new country which was settled by the British so...where the bloody hell does the accent come from? | It doesn't take long for an accent to change!
*We* even have different accents from our own parents. Or maybe you can tell more easily from your grandparents. My grandparents sound much more 'plum' than I do.
The children of the first fleet would have had a different sound from their parents, who were a unique mix of different British accents. Probably the children heard the adults, who came from different areas, and subconsciously chose bits and pieces from different adults, creating the first Australian accent.
Sometimes Australian TV replays news segments from the 1930's, 40's, 50's, 60's and 70's - each generation sounds slightly different. Recall "Skippy" in black and white, or an old "Tip Top" commercial, or the Prime Ministers in the first half of the 20th century - the further back you go, the more the accent sounds ...like the Queen - or like an old fashioned Scot or Irishman. | 2b705005-d479-4096-870b-dcabcbee2f2c |
3viobt | Why do batteries, especially cellphone, die quicker the lower the charge? | Computer technician here who regularly troubleshoots smartphone battery issues: As a general rule they actually don't. Modern lithium ion/lithium polymer batteries have small onboard processors that regulate and monitor their performance. It monitors many things but most notably it tracks how many charge cycles the battery has had and how many milliamp hours (mAh) are available for use. Every task a device performs takes a very specific amount of power and these measurements aren't arbitrary either, they're very accurate. Think of the battery as a reservoir of water with a tap attached. The more open the tap the faster it drains. The likelihood is that because you are paying more attention at crunch time you are tricking yourself into believing it is going down faster when really it's not, or, the very act of observing is draining the battery. A common statement I hear is "I can actually watch the percentage go down" and, yes, you can. Screen usage is one of the biggest drains on the battery, second probably only to heavy video processing and GPS (ALWAYS use a charger if you plan on using as a satnav). In my experience; people who don't wear a timepiece use 15-20% battery just checking the time regularly.
The other reason is that your battery is either faulty or consumed. A battery can only be charged so many times before its performance is significantly lost and is measured in Full Charge Cycles. Every total 100% equals one cycle, so 20% a day for five days equals one cycle. Most modern batteries get about 500-1000 cycles before they are considered consumed, where they go below 80% capacity of what they were when they were new. At this point the battery will have difficulty measuring exactly how much power is left and may behave erratically, shutting down at high percentages, draining faster or just shutting off spontaneously for no reason. At this point you should have your battery replaced by an authorised technician. And I don't say this lightly or because it keeps me in the job. Batteries are seriously bloody dangerous when manufactured cheaply or fitted incorrectly and most modern smartphones have "naked" battery packs, soft cells that are protected only by the phone casing itself and not in an independent casing. Incorrect handling can cause fire and really nasty fumes so do not attempt it yourself.
TL;DR It doesn't, you're just tricking yourself or there's something wrong with your battery | 69559f9d-774c-4ffe-bbfe-9406cb5592be |
2sa8pq | Why do low fuel prices have a negative long term effect? | They don't.
..although they can have. One of the things you need to remember with economics, is that very few things "do X". Economies as a system are too complicated for such easy conclusions.
In this case however: The rise of fuel prices tends to drive inflation (when fuel becomes more expensive, transporting goods becomes more expensive, so the price of goods rise, and something priced at $1 today could cost $1.1 tomorrow, ie. the money in your hand is worth less as time passes. When fuel prices drop, inflation tends to drop.
However when inflation becomes negative (= deflation), a good that costs $1 today could cost $0.9 tomorrow; so suddenly the money you already have starts increasing in value, which is an incentive for you to hold on to it. The longer you keep it, the more valuable it becomes.
As such consumption of goods and investment in future technologies drops off.
Since our (western, modernized) economies depend on private consumption & industries investing into research & development, lower fuel prices could lead to a drop in consumption.
The counterargument is that lower fuel prices (and thus lower cost of goods) would lead to more consumption, because everything is cheaper & people have more money left over.
Which of those two is more true than the other at any given moment depends on dozens if not hundred of other factors (and that usually leads to people from opposing political parties claiming their argument is true).
The middle line is that you'd want low inflation (so money doesn't devalue too quickly), while avoiding deflation; but most of all keeping everything more or less stable. No one likes disrupting effects in their macroeconomy, since there are no cookie-cutter solutions. | a4d47687-785d-4c7c-83d9-50e4561a9280 |
3cgbyk | What are/were qualudes? What were they originally intended for? What did the effect feel like? How they used? | Well, since they are impossible to find these days, no harm in discussing what they were about.
They were originally a sleep aid, prescribed to those who can't fall asleep or sleep through the night (Insomnia). People pretty quickly found out that if you resist the urge to sleep, you were hit with a pretty powerful high.
The drug itself is a depressant (like alcohol) and a muscle relaxer (like a soma or valium). As you might guess, the effect is pretty much a combination of the two (Don't combine alcohol and muscle relaxers! It's VERY DANGEROUS and can result in death easily!).
You're partially numb ("floaty"), have poor coordination/motor control/reactions. You feel dizzy, are more easily sexually aroused, and may have slurred speech-quite like alcohol. When too much is taken, the effects are like modern barbituates-delirium, convulsions, vomiting, and death through cardiac or respiratory arrest (you stop breathing, or your heart stops beating).
They were used in the same context as alcohol or other barbituates. Some used it for fun, and would go out socially or dance (just like many people dance and drink alcohol). Others would use it for relaxation or "tuning out", much like modern barbituates.
At this point, they're gone. Production officially stopped decades ago after controversy, and even underground production essentially stopped many years ago after popularity dropped. | 0f95b4e8-4bb2-4899-b993-79e476d89ee2 |
43tlvh | Why can we be woken up by others snoring but not our own? | You can be woken up (easily) if your sleep is not deep. You only snores when your sleep is deep. | c0ab67d1-b891-4d36-be51-6a6650d46e17 |
6katzf | How can birds sit on electricity cables and not be electrocuted? | Electricity will always seek to flow through the path of least resistance. If it can flow at all, it will go through the conductor that is lowest in resistance to the flow.
When a bird perches on an electrical wire, there's no change in the bird's electrical status- it offers no easier path for electricity to flow, because it's already flowing through the wire, which is *far* lower in resistance than a bird is.
If a large bird or other animal were to touch two wires or one wire and the ground (or a conductor that connects to the ground) at the same time, then it would create a path between two different electrical states (called *potential*), and then electricity would flow between those two wires through the animal. Probably very briefly, as the animal would die or burn up almost immediately.
Editing to add: Almost no electrical cables on power poles are insulated because it costs more, the insulation can crack and wear away, and it serves no purpose other than to increase expense and weight. Only in some specific circumstances are overhead power lines insulated, and it's not common. | 38aee711-82f1-4280-98d3-73968efc274e |
1ob9qk | How do they make old 70s and 80s movies in high definition when it didn't exist back then? | Film is a very high quality medium capable of storing images very high resolutions. The master prints of those films are still around and are used to create HD copies.
Back then, scans of the films were taken at relatively low resolutions because VHS tapes were the standard medium for distribution. VHS tapes are low quality and the TVs people would view them on were low quality.
Nowadays, much higher quality mediums are available for redistribution, so the films are being rescanned at more appropriate resolutions. | 57b8d6a8-4d0b-4ab5-a365-290e22a7b3ed |
48wam0 | How healthy are probiotics for you? Do they help with weight loss? | Probiotic refers to food that contains "healthy" or "beneficial" bacteria. Our intestines are loaded with bacteria that help us digest food. Probiotics contain some of those bacteria. They are generally recommended for people who are on long term antibiotic therapy, among other things, as those people will have a lower population of good bacteria in their gut.
So no, probiotics have very little if any effect on weight. | 8e4e6bf6-b319-4515-bf0f-df1235bf9f7c |
r9r1c | How Gödel Numbering works | There is a difference between the "logical leap" in terms of what it does in general and exactly what Gödel was doing. I will give you an ELI5 idea in general.
Any claim that can be proved in math can be answered by writing out a proof of that claim. This proof is nothing more than a finite collection of symbols taken from a character set (including spaces). If you assign a number to each character you can assign a unique number to each proof and mathematical claim. (Gödel involved numbering types logical statements and not types of characters, and those details are important in his proof, but the idea is coming up with a unique numbering)
For going backwards you take any number and decode it back into the characters from the character set and you get a claim and its proof. Well, mostly you get gibberish in this case, but no matter, every valid proof of every claim does come from unique numbers, that means all mathematical claims and valid proofs can be numbered.
The Gödel argument is to show there are mathematical claims which are true but for which there is no valid proof. Essentially the claim "there is no valid proof of this claim"... is a true statement, but there is no valid proof of it. | eeec46bc-ba33-4748-9310-e7399fec680f |
21kqho | What is syndication on TV? | ["Syndication" is essentially a market for programs to be sold to TV stations, to fill out their schedule](_URL_0_). For the most part, at least for broadcast TV, 'primetime' and morning news shows are the only programming produced exclusively by a network for broadcast on their own channel. Everything else is syndicated programming purchased by the local affiliate or regional association to fill timeslots.
So, shows like Jeopardy!, Xena Warrior Princess, and a lot of shows that were cancelled after the first season but continued to make episodes (e.g. Baywatch) are straight-up syndicated; they are produced independently, and channels buy the rights to broadcast the shows. There's no direct relation to the channels, so in one city it might be shown on the Fox channel, in another on CW, in another on the weird local-access channel that usually just broadcasts church services, etc.
Now, when a popular first-run non-syndicated program gets enough seasons under its belt, they take the older episodes, package them up, and sell them on the same syndication market as Xena Warrior Princess. The TV stations that need to fill out their schedule now have the opportunity to buy older episodes of popular shows to broadcast as well, because it comes with a pre-built audience -- they know people like watching *Everybody Loves Raymond*, but the indie detective police procedural might need some time to find an audience. Also, the original producers of the channel have an extra money-making outlet for new episodes, especially since a station already paying for seasons 1 through 3 are definitely going to buy season 4 when it comes available for rebroadcast. This is also why a lot of actor's contracts get up for renewal about the time syndication becomes available: more seasons means more revenue, and is thus a negotiating factor. | b170aee0-93c2-43a8-b3df-321969012737 |
284q5i | Why do apps on Google Play need me to give them access to details which are seemingly private and unrelated to the app I'm downloading? | It depends on the app; either it:
1. Is spamming malware (there is no initial vetting done on apps put onto the Google Play store; Google only takes apps down if they're reported).
2. Is sneakily but legitimately selling your information to advertisers.
3. Has features you aren't aware that utilise those features for a real and positive feature. | 0870e7ac-273c-4941-9340-4ccb8d161cb7 |
1ydajn | how do they determine traffic light timing at intersections? | There are 3 traffic control systems that I'm personally aware of. None of these terms should be considered technical or correct, I'm just a geek interested in cars who wandered one night into the part of the internet where they talk about traffic lights.
Static lights - no sensors, just timed according to existing patterns. This is the most common one out there, and most seem to be programmed based on traffic and time of day. No matter how well a static / timed light may be programmed (even compensating for time of day or day of week) traffic is inherently unpredictable and changing patterns (even over the course of months or years) will cause the lights the eventually not handle traffic patterns accordingly. These lights are most often criticized for bad timing / impeding traffic.
Old coil-in-the-pavement sensors (there are a few different styles). These are the ones where you drive over a sensor which detects the car and has the light (eventually) change to let you through. One reason it takes so long is that it was programmed with a delay to prevent the light from turning green for a car that has long since turned right on red. Also, if you ever hear about motorcycles not being able to trip a sensor, this is the kind of intersection that they're having a problem with. Most often paired with a button for pedestrians to hit in order to get the "walk" signal.
ITS (Intelligent Traffic Systems) - probably the one technical term that I know. These are intersections with cameras pointing each direction. The cameras sense cars coming and send a signal to the lights to change. It allows the lights to best serve the traffic in a dynamic way, ie adjust to unpredictable patterns in the traffic. | 5ae6261e-1c94-460e-88d8-eff7c7f06db3 |
1mxim1 | What exactly is the Dial-up sound? | They're doing a few things:
* Figuring out which protocols each modem is capable of, and selecting the best one that they both can handle.
* Sending some commands to the telephone network that switch it to a mode more useful for modems than talking.
* Measuring the qualities of the telephone connection.
* Figuring out what the highest speed they can use is.
_URL_0_ | 1ea50316-16bb-42e0-a4f0-679b7952a240 |
3ycjnh | When a relative gets into an accident, how do emergency services notify you? | Depending on the circumstances, there are a number of ways next of kin are notified of an accident:
- if the accident is fatal, all efforts are made by the police to locate the next of kin and notify them in person. This allows for support and victim services to be made immediately available. This also ensures that the person being notified is safe and doesn't do anything to hurt themselves out of grief.
- if the next of kin lives in another city/state/country then the local police agency is contacted and asked to assist in making the notification.
- if the accident is not fatal than typically social workers at the hospital will contact the next of kin by phone, advise them of the accident, and ask them to come to the hospital. Sometimes the police will assist with this type of notification if needed.
Source: I've done it many times and it sucks. | eb66041e-d0f1-47e5-b43e-1412fc295809 |
1meyel | What is going on in Syria right now regarding the war of government vs. rebels, etc. Also, what will happen now that Syria has agreed to surrender their chemical weapons? | Please read the sidebar and [the rules](_URL_0_) before participating in /r/explainlikeimfive.
> 9\. **You must search before submitting.** All posts on ELI5 are archived, so you should search before making a submission. Remember to search using *keywords,* don't just paste your title into the search bar. If your search results don't yield an adequate explanation, mentioning it in the body of your post is a good idea.
I have removed your submission because it is very similar to one of the most commonly-asked questions, or something that was asked very recently. Please don't be discouraged from making submissions in the future that are more in line with the mission and rules of this subreddit :) | e8914936-7ea7-4937-a1f7-2d7e83cef092 |
ygcab | - Totalitarianism and politics | I dont exactly agree with Schmaltzed.
Totalitarianism is political system, where the government tries to control every aspect of public but ALSO private life.
In contrast a government that just controls the economy, military, art, education, science is not perse a totalitarian government.
The greatest example is Soviet Union. It was all about building up a Nation where everyone would have equal rights and chances for a stable future. The State literally built schools, paid for your education, found a job for you, paid your pension. You never really had to worry about your future, state was promising you that stability. While it sounds great to live that , one must realize that in case you were unhappy with how things were, you had no liberty or chances to change it.
A things about Totalitarian Government ( from top of my head):
1. uses media to justify and promote itself.
2. limits freedom of speech ( as a back up to 1.)
3. strives to control every aspect of your life.
4. not perse a dictatorship
5. sells ideology, brainwashes citizens.
6. low on corruption (officials also brainwashed)
....
edit: spelling | 362a6e2a-8f80-4a98-bf5c-6a32cc4efcf2 |
5jn80f | Why is affirmative action still around? | The easiest way i can explain it is affirmative action is a set of guidelines and goals to reduce and reverse historical trends of minority groups being deprived of social and economic opportunities not available to them solely because of their background.
I saw guidelines and goals because actual quotas have been deemed unconstitutional for quite a while now, and don't actually exist. And government assistance is not ever based on affirmative action, at all. Its based on economic status, and you will find no law or statute that says otherwise, because that's illegal.
The reason all this is still around is because its still necessary. The problems still exist. The reason so many people think there's not an issue is because they are fundamentally confused about what affirmative action actually is.
Normally, this is because they never bothered to look into it and just kinda believed what other people told them, without ever verifying it. | 349cae99-909a-4717-a803-ea08bd4c5ae9 |
4mfj2m | Why can English speakers efficiently communicate with most other English speakers (regardless of dialect) but a lot of Mandarin speakers can't communicate likewise between the various dialects of Mandarin nearly as efficiently? | Because there is no clear distinction between 'language' and 'dialect'.
An important aspect of differentiating between a dialect and a language is mutual intelligibility. If two people who speak the different dialects cannot understand each other, then they speak different languages.
However, in the real world languages don't exist in isolation. They are connected to culture, history and religion, and and all these aspects are also important in whether a dialect gets to be called its own language. For example, speakers of Hindi and Urdu can easily communicate with each other. In fact the Hindi pop culture produced in India is consumed by Urdu speakers in Pakistan and vice versa. However, because of historical and religious reasons, the speakers of Hindi and Urdu like to consider them different languages. The reverse is true for Arabic. An arabic speaker from Western Africa and one from Saudia Arabia would have difficulty understanding each other. But because of cultural and religious reasons, both would claim they speak Arabic.
So why are different dialects of Chinese not mutually intelligible. Because while they are considered the same language due to historical and cultural reasons, they are as varied as the Romance languages in Europe. Wikipedia states:
> The varieties of Chinese are usually described by native speakers as dialects of a single Chinese language, but linguists note that they are as diverse as a language family. The internal diversity of Chinese has been likened to that of the Romance languages, but may be even more varied | 54eabd39-2463-4bfc-aab5-55ec0d6f4bee |
5ce185 | Why do people feel a dull ache in their forehead when an object (like a pen or finger) is brought very near to, but without touching, the point between their eyebrows? | I get the same sensation when something comes close to the area between my eyebrows. It has nothing to do with eye movement or mystisism. I cannot explain why but i can feel a slight pressure when an object is close. I have wondered about this myself. | 057eb7c3-cc74-4632-ab7a-d24028f128bd |
2nb0th | Why do my eyes tear up when I pull a hair out of my nose? | Because it freaking hurts! As an aside, I love doing that all day. I guess I should have used a throwaway for that, but who cares? :) | 8b3f07c8-75e0-46a1-a75f-8beb433f364b |
3hduxu | Why are weather forecasts still so inaccurate? | You remember the times they're wrong and rarely remember the times they're right.
Also if an app is telling you it's sunny and clear when it's raining perhaps the location services on your phone aren't functioning properly. | a6a68cf7-0f90-40f2-bad6-76c7f1aaa638 |
3plqsi | Since I'm not a Nielsen family, does pirating a show basically have the same effect as watching it on live TV? | With respect to TV ratings, if you're not participating in any special Nielsen Families (or related) program, then pirating would be effectively the same as watching the TV program live via antenna or via a passive cable/satellite tuner (e.g. using the QAM tuner built into your TV).
There are, however, cable/satellite TV set-top boxes that can technically report back to the television service provider what channels you are watching. Whether your television service provider actually collects this information and/or shares it with other parties (e.g. Nielsen) for measuring ratings, that's a whole different story (one I don't actually have the answer to)...
But certainly in terms of passive tuners (which basically just listen into one-way over-the-air / cable broadcasts), then there is no way they are collecting information about your viewership of the program and thus pirating would not affect the ratings. | c3002ab3-2727-4e7d-8cc8-7ca01e0cf407 |
4fai2c | How can gas stations charge 9/10 of a penny, when no such denomination exists? | Since there is no such denomination, they "do it" by rounding to the nearest penny. When you multiply any amount of gas by any price, you always get something that has to be rounded off.
It's their way of turning 9 cents into a dime, 99 cents into a dollar. That also gets them a tiny bit more money than if they didn't use that 9/10 of a penny in the price.
I run into people all the time who think $2.599 is two dollars and fifty-nine cents. The ruse works. | d3ad9300-31b4-442e-8a0f-cd10ff9a6a09 |
6j3xlj | Why do spicy foods affect some people more than others? | From personal experience, it's how used to spicy food you are.
The experience I've had involves home made curry; one my dad made that he considered to not be spicy at all, I agreed, was way too hot for friends I shared it with.
I imagine it's tolerance. The more spice you eat, the more you body is used to the level. | ab8282f9-61f3-445e-b3fe-405ce3543cf4 |
2gzrqh | Why does society view the exposure of the female chest so differently from that of a man's? Why do women have to cover and men don't? | In New York State wherever a man can legally be topless, so can a woman. | a00bc10b-fdd8-4d03-a6a1-440379c2c9e2 |
jg4jk | In theory, how do all of the US government armed forces (Police, FBI, DEA, etc) rank and compare to each other? | They all have different responsibilities. The Federal level is above the State. And the State level is above the Local. State level in most states acts as a sheriffs department which is just like your local police, but across the entire state and used often for rural areas that do not have a local police force.
In the case of a terrorist attack, the FBI, the CIA, the NSA, and Homeland Security would all work on the locating the perpetrators, figuring out how they did it, and if there is any other imminent threats.
The CIA would most likely work on gathering intelligence about the chain of command across the world, taking them to wherever the idea of the attack developed. The NSA would start gathering intelligence domestically through wiretaps. The FBI would do more of the foot work in investigating the actual scene and probably do some intelligence gathering of their own. Homeland Security would start investigating who the people were by checking immigration records and other international criminal activities associated with the event. Homeland Security also controls the TSA at the airport, so they would be responsible for figuring out how the terrorists were able to avoid any detection at the airport when first coming to the US and if they were on any warning lists, like the do not fly list.
For example, if a murder happened in a city that has a local police force they will be the first to the scene. If the crime involves a larger matter, like a series of murders that goes across state boundaries, then the FBI would take over. The more complex and spread out the crime the more likely the local police would hand off the case to the FBI. The local police usually remains to provide local assistance and lower level investigation (door to door questions, local probes, etc).
**Intelligence -** There are 16 intelligence elements in the United States that are supposed to work alone and together. The over-arching umbrella over these 16 elements is led by the Director of National Intelligence.
NSA and CIA. The NSA is under the Department of Defense. The CIA is an independent agency, but they are all suppose to report to the President with daily briefings and to work together, especially after 9/11.
**Department of Justice -**
Federal Investigations: FBI
Drugs: DEA
US Marshalls: More or less the police for the Courts. They handle warrants, transporting prisoners, track fugitives
**Homeland Security -** Responsible for protecting the citizenry from a terrorist attack before it happens
Secret Service: Protects the current and past president's and their families, as well as foreign dignitaries. They are also responsible for preventing the counterfeiting of US currency and US treasury bonds notes.
Many others: TSA, Immigration and Customs Enforcement (ICE), Citizenship and Immigration Services, Customs and Border Protection.
Edit: Changed state level police per the comments below. | 342bfd42-b5c0-4f5c-875c-91f9ed7dcc6b |
4qodrq | Why do homegrown plants need constant attention such as water or they will die, while wild plants are left alone and flourish? | Wild plants die all the time. The ones you see are the few that lived - natural selection. They are outdoor so they get water from rainfall.
Indoor plants are often from another region. They are constantly at "room temperature", something that no plant is naturally accustomed to, so we often get plants from climates that have milder warm weather or plants that are especially hardy. They must be watered because, being indoors, they get no water from nature.
In the wild, if the plant dies who cares, there are likely others nearby that live on. In a house, you have a single plant and want to make sure it stays alive.
Also, plenty of houseplants require water and care like once a week. That is not "constant attention" by any stretch of the imagination. | ea3d8c86-1657-497b-9bf2-9de0be209ba3 |
2itdwa | Why are Hazmat suits so big and bulky? How come they can't make them smaller and slimmer? | They are both positive pressure and most contain a SCUBA apparatus. This alone results in a system that isn't small. Additionally, the material the suit is made from should be chemical and puncture resistant, this adds thickness. Additional layers may be worn underneath depending on the situation encountered. | 2e1aa52b-192c-41b9-bc3b-b0fb32a692ac |
3pl0ce | Why are actors/directors/crews not employees of major studios (or are they)? | Movie studios used to operate this way many decades ago. It was referred to as the star system. The decline of this method of operating came about largely because studios became notorious for exploiting actors and heavily restricting or controlling their careers. The system also tended to favour the development of a star's personal image, rather than focus on the quality of the acting. People in the entertainment industry still enter into contracts for all sorts of projects, however the goal of most artists is generally to retain creative control over their careers and being signed to lengthy contracts with studios obviously limits that. | 0c406a84-8191-4268-b066-540733d6efcd |
30pb6y | why is it easier to balance on a bicycle when moving than when standing still? | I actually did a little research project on this a few years ago.
There are two main sources of tilting: the moment of force from gravity, and the moment of force from the centripetal force.
What you have learned subconciously is how to use your steering weel as input to use the centripetal force to balance out what the gravitational force does. (to show you how subconcious this motor skill actually is, try swapping your hands so your arms are crossed. Don't do this on a hard surface because you're going to fall)
Additionally, there are some facets that make it easier for you. Geometry can be optimised so the bike has some self steering properties [theres a lot that can be said about this and I'm not going into it all]. When it starts tilting due to gravity the steering wheel will automatically turn to generate a centripetally induced tilt. Note that this results in an oscillation and this can be clearly seen when you push a bike without a rider, it will go in a straight line initially, then start oscillation with an ever increasing amplitude and eventually crash. Also, gyroscopic effects of the wheels increase stability (for motorbike riders: compare a real motorcycle passing a truck vs a motoscooter passing a truck).
Common misconceptions are that you balance by leaning while driving, or pushing on the footpegs/pedals or steering wheel.
Also interesting to note its very counter-intuitive. To go left you actually steer right first. For instance, R/C motorcycles (yes its a thing) have a servo that pulls/pushes (with a spring) on the steerig wheel but the servo controls are reversed: steering to the left on the controller will put pressure on the wheel to steer to the right.
To finally answer your question: without forward speed you cannot create the centripetal force.
[edit]: Sorry, I got a bit carried away and made it too technical, I don't frequent ELI5 I just saw a subject I know a lot about and wanted to help... /u/brierrat did a better job perhaps. | 85619bf2-3d24-476e-9911-027022129a7f |
3kqfsv | Why do deeply religious people badmouth other religions? | From their perspective, other religions *are* evil.
If you believe your immortal soul goes to heaven you believe the right stuff, and goes to hell if you believe the wrong stuff, other religions are Satan's trick to try to lead you into damnation. To you, they are literally the worst thing in the world. | 8948b825-e76d-40f6-8ca7-c5927e4565e5 |
1nmrgt | When you download a newly aired episode of a show, where/who does that file come from? | Someone runs their cable box's output into a computer which captures the video stream and saves it as a video file. That is then uploaded. The capture and creation of video files isn't unique to media companies you know. | aa0327c6-5a87-4678-8e26-8fd995ab53af |
1pszv9 | Why did society's view of 'The Future' change from being classically futuristic to being post-apocalyptic? | It's easy to underestimate the amount of knowledge and scientific advancement that have taken place in the last fifty years. In the movies, scientific achievements solve problems; in the real world, they often highlight them.
We got more and more information on the problems with the environment, with the political system, with poverty and class inequality, corporate greed, and all aspects of our society. And the media perpetuated the shocking and fearful in order to sell their services. We arrived at the future and saw ourselves still stuck with the same problems we've always had, the same problems we will probably always have. So it's easy to turn to cynicism and extrapolate that we're hopeless and will eventually self-destruct in one way or another.
I think of the situation somewhat differently...like what happens when someone hurts themselves badly in public. They're bleeding badly and everyone is watching, but because nobody is doing anything, nobody does anything. Until someone breaks ranks, takes off their shirt and starts applying pressure to the wound. I believe individual effort will push us towards a better future, but it's not something that's going to happen on its own.
Anyway, TLDR; he that increaseth knowledge, increaseth sorrow.
**Edit:** Sorry for making the "problems with society" overwhelmingly liberal. But substitute in whatever you're concerned about and I think the point still holds. Also, keep scrolling down for a lot more interesting responses and other answers which point to more concrete events in history.
**Edit 2:** Thanks generous individual for the gold. Go team Reddit! Keep asking questions and having conversations. | 24eddce5-a8e7-4cd5-8ea6-2449f67d7917 |
5eehqj | Why are the directions "left" and "right" associated with liberal and conservative political philosophies? | It comes from the French Revolution when people loyal to religion and the king would gather to the right of the president of the National Assembly while supporters of the revolution would gather on the left. The right thus became associated with traditionalism and conservatism while the left with equality and revolution. | dac7a631-b98b-4e00-bfa3-3e2f18d8a421 |
16oboy | why is there a feeling of total disgust for men after they finish masturbating...and what causes it | Your mind pretty much goes from a high state of pleasure to a state of reason in a matter of seconds... | 176e8564-c158-40ad-9802-e162cc17cd6d |
2xj10s | police paperwork | Note: I am not a law enforcement officer, but I have gone through police academy and I personally know many officers. Each jurisdiction will be different and contain different protocols about who writes the report and what they write and what papers they use, so this is not a definite answer for everywhere.
-----
> How is it that other cops can be given paperwork from other cops to do
Usually they can't unless the other officer was at the scene. There may be provisions that state otherwise, but I highly doubt it.
> what kind of information do they need to write up
EVERYTHING. Literally, the reports need to be very detailed and include everything that could even be remotely important to the scene. Names, birthdates, SSNs, addresses of everybody involved. Time they received the call, time arrived at scene, place of the scene, who reported there, what complainant claimed happened, any evidence to back it up, what suspected perpetrator claimed, and so on and so forth.
I know an officer (Sheriff's Deputy in Ohio) that habitually reports what uniform they are wearing at the time.
> are there different types of paperwork
Yes. Most places have a basic officer's report used for the narrative on most calls. Then there are specific reports for accidents that include drawings to show damage on the vehicle(s) and room to sketch the scene of the wreck. There are other types of reports, but I don't know them offhand.
> does paperwork really take hours to complete?
It can. If something big happens or there were many incidents over the shift, it can take a long time to write everything up. | 422d7292-e61f-409b-aa59-0deff773588b |
lbmno | Differences between IVR, MMP and the American voting system. | America has FPTP also. Basically, whoever gets the most votes wins. In some cases they require a majority. Then they take the top two and have a runoff.
The problem with this is as follows. Let's say we have three candidates, Alice, Bob, and Charlie. 60% of people like Alice or Bob, but hate Charlie. The other 40% like Charlie but hate Alice and Bob. Voting day comes, and Alice gets 25%, Bob gets 35%, Charlie gets 40% and wins. Now 60% of people are mad.
IRV means you would rank your options instead and require a majority. In the example above, Since Alice had the fewest votes, she drops out, and people who voted for Alice have their second choice get their vote. Now the votes are 60% Bob and 40% Charlie. The majority of people are happy with this.
MMP I am not super familiar with, but this is how I understand it. Sometimes, It's more important what party someone is a member of than who they are. Say, all the blues always vote the same way, and all the reds vote the same way. You have a district that is 55% blues and 45% reds, and they are electing 10 representatives. With MMP, you vote for the party, and there are 6 blues elected and 4 reds. Without it, one popular blue could get 55% of the votes, but the 45% reds vote 5% each for 9 red candidates. Then we've elected 1 blue and 9 reds from a district that is 60% blue. You can see why the blues don't want this. | ba440fa1-ceac-491f-b1e8-81d9d0f31586 |
58y4jm | How do nations determine their currency value? | Most currencies are not regulated in the way you say, countries do not set the values of their currency in international trade themselves. This was not always the case (see "gold standard"), but now, most currencies are floated on an exchange, the Foreign Exchange Market, where the value of each currency is determined by market demand. | 35673543-d132-4b56-aadc-f446444c5699 |
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