id stringlengths 10 10 | question stringlengths 18 294 | comment stringlengths 28 6.89k | passages list | presuppositions list | corrections list | labels list | raw_presuppositions list | raw_labels list | raw_corrections list |
|---|---|---|---|---|---|---|---|---|---|
2018-08036 | Why does a guitar have harmonics only on certain parts of the fretboard/string? | First you need to understand the concept of overtones. Let's say you play the open E string. The main and strongest tone you're going to hear is the E note, because that's the main frequency the string is vibrating at. But because the string isn't vibrating at exactly the same speed across the whole string \(the middle of the string will travel further in the middle of the string than it will closer to the nut or bridge\) the string will also produce a variety of overtones \(different frequencies to the main note\). This is what gives instruments \(and even individual strings on instruments\) their characteristic sound. If you play the open top E string on a guitar, you can play the same note at the same pitch by playing the B string fretted at the fifth fret...but even though they're the same note at the same frequency, they sound subtly different...and the reason for that because you're 'shortening' the B string, and the B string has a different mass, so it's producing different overtones. A harmonic is an overtone that is a multiple of the base frequency of the string. For example, if a string vibrates at 100hz, its first harmonic will be 200hz, the next, 300hz and so on. Now, a guitar string has 'dead spots' where the string doesn't move \(the nut and the bridge saddle\), and the area it can move \(the rest of the string\). When the string is particular thickness and tension it 'wants' to vibrate at a specific frequency \(the note you've tuned it to\). If you lightly touch the string at the 12th fret, you're creating a new 'dead spot' on the string, the same as the dead spot at the nut and saddle. Now, because the main frequency, the note you'd get if you played the string open, doesn't have a dead spot at the 12th fret, the main note won't sound. Basically, physics won't allow the string to vibrate at the main frequency... but the harmonic *does* have a dead spot at the 12th fret. In essence, it's like we've moved the nut up to the 12th fret, so while we don't hear the main note, we do hear the harmonic. Basically, what we're doing is cancelling out the main frequency so we only hear the overtones, and at that spot on the string, the only overtone that can be produced is the harmonic. So, the reason we can only produce harmonics at certain parts of the string is because those are the areas where we can create a dead spot that will allow the string to produce an overtone that is a multiple of the base frequency of the string. It's why every string has a harmonic at the 12th fret, because the 12th fret is the halfway point of the string, so by creating a dead spot there, we're halving the length, which doubles the frequency.. | [
"Harmonics are produced on the instrument by lightly touching a string (as opposed to fretting it) at any of several points along its length. The fundamental tone will not vibrate; specific overtones, however, will, resulting in a chimelike tone. Harmonics produced by this method based on open-string fundamentals a... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04484 | Why haven’t humans acquired immunity against common cold? | Some people are probably more resistant than others. But the cold virus mutates extremely fast, so it's next to impossible to develop a successful true immunity. | [
"In the United Kingdom, the Common Cold Unit was set up by the Medical Research Council in 1946 and it was where the rhinovirus was discovered in 1956. In the 1970s, the CCU demonstrated that treatment with interferon during the incubation phase of rhinovirus infection protects somewhat against the disease, but no ... | [
"No humans have acquired immunity against the common cold.",
"With how long the common cold has been around, humans should have acquired immunity by now."
] | [
"Some people are probably more resistant than others.",
"The cold continuously mutates therefore its difficult for humans to be fully immune."
] | [
"false presupposition"
] | [
"No humans have acquired immunity against the common cold.",
"With how long the common cold has been around, humans should have acquired immunity by now."
] | [
"false presupposition",
"false presupposition"
] | [
"Some people are probably more resistant than others.",
"The cold continuously mutates therefore its difficult for humans to be fully immune."
] |
2018-02343 | Why is English the World's language? | The British Empire became the largest and most powerful empire in the world with colonies all over the place, and they held that position for several centuries. Doing this means they spread their language all over the world. The US became a Superpower after WWII and due to the economic hegemony we established any country that wanted to do business with us used our language (due to being the more powerful country) to do it. So English became the lingua franca of the last several hundred years, just like Latin was during the Roman era. | [
"Although falling short of official status, English is also an important language in several former colonies and protectorates of the United Kingdom, such as Bahrain, Bangladesh, Brunei, Cyprus and the United Arab Emirates.\n\nSection::::English as a global language.\n",
"Because English is so widely spoken, it h... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-18213 | How do we or scientists know what sounds dinosaurs made? | Taken from quora: The discovery of the fossil vocal organ of an ancient Antarctic bird suggests that dinosaurs couldn’t sing, but maybe honked. A team of scientists have discovered the oldest known vocal organ of a bird in an Antarctic fossil of a relative of ducks and geese that lived more than 66 million years ago during the age of dinosaurs. Birds are direct descendants of dinosaurs and are considered living dinosaurs by scientists. The apparent absence of the vocal organ — called a syrinx – in non-bird dinosaur fossils of the same age suggests that other dinosaurs may not have been able to make noises similar to the bird calls we hear today. That’s according to the research, published in Nature on October 12, 2016.Julia Clarke, a paleontologist at the University of Texas at Austin (UT), discovered the fossil syrinx and led the analysis. She said in a statement:This finding helps explain why no such organ has been preserved in a non-bird dinosaur or crocodile relative. This is another important step to figuring out what dinosaurs sounded like as well as giving us insight into the evolution of birds. The asymmetrical shape of the fossil syrinx indicates that the extinct species could have made honking noises via two sound sources in the right and left parts of the organ. | [
"Section::::Paleobiology.:Hearing.\n",
"BULLET::::- Phil Currie hypothesized that troodontids' basisphenoid bullae may have helped them hear very low frequency sounds.\n\n1986\n\nBULLET::::- Jacques Gauthier classified troodontids as deinonychosaurs.\n\n1987\n\nBULLET::::- James H. Madsen described the new genus ... | [] | [] | [
"normal"
] | [
"It seems illogical that scientists would know what extinct dinosaurs sounded like."
] | [
"normal",
"false presupposition"
] | [
"The discovery of a fossil vocal organ of an extinct bird suggests dinosaurs couldn't sing but perhaps honked via two sound sources in the right and left parts of the organ."
] |
2018-03225 | How are professional musicians able to play whole sets and not make any mistakes? | 1. Practice. Lots and lots of practice. 2. Bluffing (AKA self-confidence): a LOT of mistakes can be played around/over/through 3. Perception (also self-confidence / stage presence): are your SURE they didn't make any mistakes? How exactly would you know? | [
"Section::::Quotes.\n\nBULLET::::- \"Improvisation is an intuitive process for me now, but in the way in which it's intuitive, I'm calling upon all the resources of all the years of my playing at once: my academic understanding of the music, my historical understanding of the music, and my technical understanding o... | [
"Professional musicians play whole sets without making any mistakes.",
"Musicians can play whole sets and not make any mistakes during their time playing."
] | [
"Professional musicians make mistakes while playing, but they either bluff their way through or use self-confidence to make it appear they did not make mistakes.",
"Musicians can possibly make mistakes during their time playing. "
] | [
"false presupposition"
] | [
"Professional musicians play whole sets without making any mistakes.",
"Musicians can play whole sets and not make any mistakes during their time playing."
] | [
"false presupposition",
"false presupposition"
] | [
"Professional musicians make mistakes while playing, but they either bluff their way through or use self-confidence to make it appear they did not make mistakes.",
"Musicians can possibly make mistakes during their time playing. "
] |
2018-16093 | How does radio frequencies between walkie talkies and the FM-radio stations work? | There are two basic ways to transmit a signal using radio waves, amplitude modulation (AM) and frequency modulation (FM). Which one a walkie talkie uses depends on the walkie talkie. Some walkie talkies do use FM, so in that respect, they are just like the little FM radio stations. How does that work? Let me use visible light as an analogy. After all, radio waves are basically a form of light that we can't see. Light and radio are forms of electromagnetic radiation. All electromagnetic radiation can be described in terms of its *frequency* and its *amplitude*. In visible light, we perceive different frequencies as different colors, and different amplitudes as different brightnesses. A radio antenna is like a light bulb where we can precisely control the color and brightness of the radio waves. So, let's say we have this color/brightness-changing lightbulb, and we want to use it to send information to someone far away. We turn on the lightbulb and set it to a single color, let's say green. We have two different ways we can send information. We can alter the brightness, or we can alter the color. We can call these two methods for transmitting information Brightness Alteration and Color Alteration. OK, thesaurus time. Brightness = > Amplitude Color = > Frequency Alteration = > Modulation Brightness Alteration = > Amplitude Modulation (AM) Color Alteration = > Frequency Modulation (FM) That's basically how a simple radio works. | [
"While the bulk of personal walkie-talkie traffic is in the 27 MHz and 400-500 MHz area of the UHF spectrum, there are some units that use the \"Part 15\" 49 MHz band (shared with cordless phones, baby monitors, and similar devices) as well as the \"Part 15\" 900 MHz band; in the US at least, units in these bands d... | [] | [] | [
"normal"
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"normal",
"normal"
] | [] |
2018-00696 | Why are antibiotics completely ineffective against viruses? | Bacteria are tiny animals. They eat, they breathe, they have a metabolism that turns food into energy, they do all the normal animal things. Antibiotics work by interrupting some part of that process that keeps bacteria alive. They are basically poisoned to death. Viruses are not alive. They are very simple biological machines. They don't eat, they don't breath, they don't have a metabolism. What they do is knock into healthy cells and inject protein into them. These protein strands hijack the cell, and cause it to make more viruses. So you can't poison a virus, it'd be like trying to poison a clock or or a can opener. To stop a virus it needs to either be prevented from penetrating healthy cells (by somehow enhancing the cells to resist it) or physically attacked and destroyed by your body's natural defense cells. So anti-virals focus on strengthening your own natural defense responses and helping them to target and destroy viruses. | [
"Specific antiviral drugs are used to treat some viral infections. These drugs prevent viruses from reproducing by inhibiting essential stages of the virus's replication cycle in infected cells. Antivirals are used to treat HIV, hepatitis B, hepatitis C, influenza, herpes viruses including varicella zoster virus, c... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-05556 | Water Loss due to Agriculture? | You're right and wrong. The water used in agriculture (growing that almond for instance) is not destroyed. Almost nothing we do destroys water permanently. The water participates in the plant's transpiration cycle, is used to build parts of the plant, and is released as water vapor into the atmosphere, where it eventually goes and rains on someone (since I live in Seattle, probably me). Or for the water incorporated into the plant's tissues, digestion, rotting, or even burning, will release it. So it all comes back. That's where you're wrong. However, you are right that water can be moved from very useful locations and states, to less useful locations and states. Water in a reservoir in southern California is very, very useful, because lots of very dry cities and agricultural counties desire it. Water raining on me in Seattle is a lot less useful, because we have more than enough. Water in the ocean is the same. So it is definitely possible to overuse water in local areas, thereby moving it from places you want it, to places you don't. | [
"Water management is needed where rainfall is insufficient or variable, which occurs to some degree in most regions of the world. Some farmers use irrigation to supplement rainfall. In other areas such as the Great Plains in the U.S. and Canada, farmers use a fallow year to conserve soil moisture to use for growing... | [
"water is lost due to agriculture.",
"Agriculture causes water loss."
] | [
"water is not lost, it just gets used and eventually evaporates back out of the plants to continue in the water cycle. ",
"Water used in agriculture is not lost but converted to other forms such as rain."
] | [
"false presupposition"
] | [
"water is lost due to agriculture.",
"Agriculture causes water loss."
] | [
"false presupposition",
"false presupposition"
] | [
"water is not lost, it just gets used and eventually evaporates back out of the plants to continue in the water cycle. ",
"Water used in agriculture is not lost but converted to other forms such as rain."
] |
2018-02072 | Why do candles smell burnt when they go out, but not before when they are still burning? | I will speculate it is because the soot emanating from the candle after it is out is not the same chemical composition as the byproducts from more complete combustion. That white smoke after you blow it out is aerosolized wax, and is flammable. | [
"Also known as \"rectification\", the raw materials are directly heated in a still without a carrier solvent such as water. Fragrant compounds that are released from the raw material by the high heat often undergo anhydrous pyrolysis, which results in the formation of different fragrant compounds, and thus differen... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-14407 | Why is perpetual energy from gravity impossible? | Gravity pulls things down. You can exploit this for energy, but only once. Once the object has exhausted its "gravitational potential" (i.e. hit the ground) you can't extract any more without first picking it up again. We do extract energy from falling water in hydroelectric dams, but again the water can only pass the dam once. | [
"A consequence of the law of conservation of energy is that a perpetual motion machine of the first kind cannot exist, that is to say, no system without an external energy supply can deliver an unlimited amount of energy to its surroundings. For systems which do not have time translation symmetry, it may not be pos... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04165 | Why is the California High-Speed Rail taking longer than the Transcontinental Railroad, to be built? | The Eastern part of the transcontinental railroad, the Union Pacific, was over flat, dry, unforested, undeveloped land, so encountered few challenges and was much longer than the other part. The Western leg, the Central Pacific, though it went through rugged mountains, was much shorter and still didn't have to deal with developed areas. The entire project was through wilderness, and the 19th century didn't care about things like the visual impact on the landscape, biodiversity preservation, or toxic pollution from exposing underground metals to the watershed. So when they came to mountains, they blasted through them. When trees were in the way, they cut them down. When rivers were in the way, they built bridges over them, and weren't too concerned about the long-term safety and stability of those bridges. The California High Speed Rail is the exact opposite end of the spectrum, though it has some similarities. The largest part of the track would go through the flat, open, sparsely-populated Central Valley, and as is predictable, is proceeding much more quickly than the other parts near the Bay Area and LA. Those two urban metropolises are among the most environmentally conscious in the country, and while not particularly dense, still have a *lot* of people and thorough development. Building new track through those areas is a regulatory nightmare, which is why alternative proposals like Elon's Musk's underground traffic tunnels are drawing so much attention. | [
"Section::::Current state and regional efforts.:West Coast.\n\nSection::::Current state and regional efforts.:West Coast.:California.\n",
"After construction reaches Bakersfield in about 2019, the Amtrak \"San Joaquin\" will begin using the HSR tracks. These trains will be able to significantly reduce their trave... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-18263 | How are carnivores able to get by with extremely little fiber in their diet? | Dietary fiber refers to non-digestible solids in our food that help "push" the digested mass through your digestive tract. For humans, this is mainly plant fibers that our bodies cannot break down. Carnivores also get dietary fiber from their diet. Undigested or partially digested parts of an animal such as the skin, fur, cartilage, or bones can act as dietary fibers to help push the digested matter through. | [
"Civets are unusual among feliforms, and carnivora in general, in that they are omnivores or even herbivores. Many species primarily eat fruit. Some also use flower nectar as a major source of energy.\n\nSection::::Diet.:Coffee.\n",
"Section::::Processing.:Nutritional aspects of processing.:Fiber.\n\nProcessing i... | [
"Carnivores have very little fiber in their diet."
] | [
"Carnivores do get dietary fiber from their diet in the form of animal skin, fur, cartilage, bones."
] | [
"false presupposition"
] | [
"Carnivores have very little fiber in their diet."
] | [
"false presupposition"
] | [
"Carnivores do get dietary fiber from their diet in the form of animal skin, fur, cartilage, bones."
] |
2018-06366 | Why did it take so long for console games to run on 60fps while pc has this option for decades? | PC performance is limited by your budget. You could go build an insane $10000 rig right now to run games at 4k, 120fps if you wanted to. Consoles need to be cost effective, and historically their hardware is already somewhat middling and out of date when they're released. The console manufacturers have no interest in pushing out a thousand dollar system nobody will buy. | [
"Section::::History.:Internet capabilities.\n\nBy the sixth generation the console market had become larger than the PC market.\n",
"CRT refresh rates have historically been an important factor in electronic game programming. Traditionally, one of the principles of video/computer game programming is to avoid alte... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-00159 | Why are we able to move our eyebrows? | Non-Verbal communication was important when it came to evolution. That's why we have so many muscles in our faces. (I'm not an expert on this subject) | [
"Blood supply to the forehead is via the left and right superorbital, supertrochealar, and anterior branches of the superficial temporal artery.\n\nSection::::Function.\n\nSection::::Function.:Expression.\n\nThe muscles of the forehead help to form facial expressions. There are four basic motions, which can occur i... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-19798 | How do Satellites handle the millions if not billions of devices outfitted with GPS chips? | GPS chips don't "request". They're passive devices. They listen to a continuous broadcast from each GPS satellite and use some crazy math to figure things out themselves. It's a one way transmission from the GPS satellite to the receiver. | [
"The OmniSTAR service options include both single-frequency (L1 only) code phase DGPS solutions and dual-frequency (L1/L2) carrier phase solutions. Accuracy depends on satellite geometry, local conditions, receiver capability and other variables, but typically the L1-only solution (VBS - Virtual Base Station) yield... | [
"GPS chips send messages to satellites.",
"Satellites handle millions if not billions of device requests."
] | [
"GPS chips monitor information sent by satellites.",
"The satellites just emit information. It is the user end device that the computation of where the device is. "
] | [
"false presupposition"
] | [
"GPS chips send messages to satellites.",
"Satellites handle millions if not billions of device requests."
] | [
"false presupposition",
"false presupposition"
] | [
"GPS chips monitor information sent by satellites.",
"The satellites just emit information. It is the user end device that the computation of where the device is. "
] |
2018-20210 | Why do scars in the palm of your hand hurt/sting more than on the upper side of the hand? | Nerves in our skin allow us to feel things, including temperature, sensation, and pain. Different parts of our bodies contain more or less nerves depending on what we use that body part for. Because of that, the skin on our main “feelers” (our hands) have more nerves than, say, our elbows. We have more nerves on our palms and the bottoms of our fingers than on the upper side for this same reason. We use the bottoms of our hands to hold and feel things, so we have more nerves there. More nerves mean that we feel more pain, too. | [
"Janeway lesion\n\nJaneway lesions are non-tender, small erythematous or haemorrhagic macular or nodular lesions on the palms or soles only a few millimeters in diameter that are indicative of infective endocarditis.\n\nOsler's nodes and Janeway lesions are similar and point to the same diagnostic conclusion. The o... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-06331 | Why does a wooden pipe, itself, not burn while in use? | A pipe will burn but very slowly. As you use the pipe ash and residue builds up in the bowl, called a cake, which will prevent it burning further. | [
"The caked layer that helps prevent burning through the bottom or sides of a briar wood pipe may damage other pipes, such as meerschaum or clay. As the cake layer heats up, it expands and may cause cracks or breaks in non-briar pipes.\n\nSection::::Use.:Smoking.\n",
"All wood will release creosote vapors when bur... | [
"A wooden pipe doesn't burn itself while in use."
] | [
"A wooden pipe will burn but very slowly."
] | [
"false presupposition"
] | [
"A wooden pipe doesn't burn itself while in use.",
"A wooden pipe doesn't burn itself while in use."
] | [
"false presupposition",
"normal"
] | [
"A wooden pipe will burn but very slowly.",
"A wooden pipe will burn but very slowly."
] |
2018-18786 | How does diet soda have zero calories but is still awful for you? | There’s lots of reasons why things are bad for you. A steel axe is calorie free but I would advise against swallowing one. The reason why diet sodas are still bad for you is because they make your body think its swallowing something sweet. When it thinks that, it releases a hormone called insulin that is designed to take the incoming sugar from the food and take it out of your blood, putting it into your cells. If this hormone is released but there is no sugar being eaten (since its diet) it creates a shortage of sugar in your blood. Your blood sugar needs to be kept within a small range or it is unhealthy for you. Long story short, diet sodas can mess up your hormone system or turn blood sugar into fat by storing it (by insulin) when it doesnt need to | [
"The widespread, though not universal, agreement that the newest formulations taste much more \"normal\" (sugar-like) than the older diet soft drinks have prompted some producers, such as Jones Soda, to abandon the \"diet\" label entirely in favor of \"sugar-free\", implying that the taste is good enough to drink e... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-00549 | Why do you have to put premium gasoline in certain vehicles? Will it really harm them if you put in regular? | The more you compress the air/gas mixture the more power you can get from it, but compressing it makes it hot and it can explode too early which will hurt the engine Premium gas has a higher octane rating than regular which means you can squeeze it more before it explodes. If you put regular gas in a high compression engine it will be exploding before the piston is at the top which is no good Modern engines have sensors to detect premature detonation (aka engine knock) and change how they're running to avoid damage but sacrifice performance to do so | [
"BULLET::::- Fast Stop Express - Diesel (select locations only)\n\nBULLET::::- G500 (Mexico)\n\nBULLET::::- Hele\n\nBULLET::::- HFN - Hawaii Fueling Network\n\nBULLET::::- Holiday (U.S., Canada)\n\nBULLET::::- Irving Oil (U.S., Canada)\n\nBULLET::::- Kirkland Signature Gasoline (U.S., Canada, Mexico)\n\nBULLET::::-... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-04963 | How did artists like Van Gogh paint self-portraits without the painting being mirrored? | You could always make a trace first and flip it if you're that concerned about 100% accuracy, but I wouldn't assume that a lot of famous self portraits *aren't* mirrored unless there's a clearly defining asymmetric feature that's present in both portaits and self portraits. Just a note about Van Gogh specifically, you could definitely get a picture done in 1880. | [
"Portraits of Vincent van Gogh\n\nThis article refers to portraits of Vincent Van Gogh (1853–1890). It includes self-portraits, portraits of him by other artists, and photographs, one of which is dubious. Van Gogh's dozens of self-portraits were an important part of his oeuvre as a painter. Most probably, van Gogh'... | [
"Self portraits from artists are not mirrored. "
] | [
"Famous self portraits could be mirrored. "
] | [
"false presupposition"
] | [
"Self portraits from artists are not mirrored. ",
"Self portraits from artists are not mirrored. "
] | [
"normal",
"false presupposition"
] | [
"Famous self portraits could be mirrored. ",
"Famous self portraits could be mirrored. "
] |
2018-04534 | How does somebody survive a jump from 11 meters into a pool of 30cm? | There are a lot of things happening all at once. First When you make contact with something that thing wants to apply the same amount of force that you applied to it back to you. But if that thing is to small or light to do so, the extra force turns into movement. Eventually with enough movement the force is canceled out. Water takes much less force to move than concrete or another solid which means it won't stop you as fast and you feel less of an impact.(for reference it only takes about 90cm of water to stop a .50cal bullet.) At the same time we've all dove into a pool only to end up with a sore stomach. This is because water likes sticking to itself which gives the water surface tension. (You can actually float a paperclip on top of this tension and see the water bend around it if you're really careful.) This is why the first thing to hit the water when they dive is the hands. This breaks the surface of the water and greatly reduces the tension. The other big thing that happens is the force being spread out, both in the water and in the diver. In the water each bit of water pushes on every other bit of water so you eventually have all the water moving at once which means the force ts spread out a lot. However the force isn't spread evenly which is why there is a splash and some water goes farther than the rest. The diver however wants to spread the force on his body as evenly as possible. which is why the second part of the body to hit the water is the chest. The chest has a lot of muscle which is really good as spreading out force. the bones in the chest are also a bit more flexible than your other bones meaning they also help spread the force. Also the chest is really close to the center of your body meaning the force has more space to spread out before it runs out of things to spread to. Lastly because the diver is hitting the water at an angle, the force will spread out more as more of their body makes contact with the water. To demonstrate this you can drop a book that is perfectly level and get a loud noise, but if you drop it at an angle the noise will be much quieter. tl;dr water stops you slower and your chest is surprisingly flexible. | [
"BULLET::::- Cofre en el Agua (Coffin in Water): Participantes lay down inside a transparent glass coffin being submerged underwater. At the signal of a pilot light, the Participante must open a lock using one of three keys to release themselves from the coffin and swim toward the edge of the pool marked with the l... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-01525 | Why isn't the Seven Years War considered the first world war? | To be a world war a minimum of 3 world powers from at least 2 major regions of the world must be fighting each other. While the 7 years war involved many of the World Powers, it was a European conflict. The only regions outside of Europe involved were the colonies of the European Empires and that simply does not count. It frankly was not big enough. | [
"The war has been described as the first \"world war\", although this label was also given to various earlier conflicts like the Eighty Years' War, the Thirty Years' War, the War of the Spanish Succession and the War of the Austrian Succession, and to later conflicts like the Napoleonic Wars. The term \"Second Hund... | [
"Seven Years Wat should be the first world war."
] | [
"It was not a world war because it was a european conflict. "
] | [
"false presupposition"
] | [
"Seven Years Wat should be the first world war."
] | [
"false presupposition"
] | [
"It was not a world war because it was a european conflict. "
] |
2018-03792 | How come a person gets dehydrated when drinking certain liquids, such as beer? Shouldn't all liquids provide hydration? | Alcohol prevents the pituitary gland from secreting something called Antidiuretic Hormone (ADH). ADH signals your kidneys to return water to your bloodstream instead of sending it to your bladder. Enough alcohol means that ADH isn't reaching the kidneys, so they stop returning the water they filter. So yeah, you're adding water when you drink the beer, but not enough to overcome what the kidneys are removing. That's why pee is clear when you're drunk, and then dark when you wake up the next day. The alcohol has worn off, the pituitary can secrete ADH again, and your kidneys start returning water to your blood in an attempt to counter dehydration. TL;DR: Kidneys remove water unless told otherwise. Alcohol blocks the 'return water' signal, so the kidneys drain as much water as they can, dehydrating you. | [
"Briefly, to excrete free water from urine, the urine flow (which is solute clearance + free water clearance) will equal the rate of solute excretion divided by the urine osmolality. With a diet of only solute poor beer, only about 200–300 mOSM (normal 750 mOSM to greater than 900 mOSM) of solute will be excreted p... | [
"Beer should not dehydrate you because it contains water. "
] | [
"Beer contains alcohol and alcohol prevents the pituitary gland when creating ADH, ADH signals kidneys to return water to the bloodstream, instead of the bladder, which means the water you consume is less than the water removed."
] | [
"false presupposition"
] | [
"Beer should not dehydrate you because it contains water. ",
"Beer should not dehydrate you because it contains water. "
] | [
"normal",
"false presupposition"
] | [
"Beer contains alcohol and alcohol prevents the pituitary gland when creating ADH, ADH signals kidneys to return water to the bloodstream, instead of the bladder, which means the water you consume is less than the water removed.",
"Beer contains alcohol and alcohol prevents the pituitary gland when creating ADH, ... |
2018-00819 | How come you can hold your bladder for hours, but as soon as a toilet enters your vision it feels as though you’re going to explode? | Your brain is what's suppressing the urge to urinate when it knows that there's no chance of urinating at the time. Once you're near a toilet, the suppressing wears off, and you feel the full urge to urinate. You can think of it as a measure to ensure that you take the opportunity to urinate when you can. | [
"Section::::In fiction.\n\nBULLET::::- Georgia Lass, the protagonist of comedy-drama television series \"Dead Like Me\", is hit and killed in the pilot episode by a toilet seat falling from the deorbiting Mir space station.\n\nBULLET::::- The character Tywin Lannister in the book \"A Storm of Swords\", a novel from... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-19059 | Why does the temperature sometimes feel cooler or warmer than it actually is? | You don't really feel temperature - you feel heat leaving or entering your body. This is why wind chill works. If the air is still (and you are standing still), then heat leaves your body more slowly. But if it is windy, then the wind is blowing your body heat away, and you feel colder because heat is leaving you faster. Similarly, on a humid day, it feels hotter because you are less able to use sweat to lose heat. Being in direct sunlight feels hot because it is making heat enter your body, despite the air being of a similar temperature. | [
"Section::::Influencing factors.:Relative humidity.:Interplay of temperature and humidity.\n\nVarious types of apparent temperature have been developed to combine air temperature and air humidity. \n\nFor higher temperatures, there are quantitative scales, such as the heat index.\n\nFor lower temperatures, a relate... | [
"The temperature sometimes feels cooler or warmer than it actually is."
] | [
"One doesn't really feel temperature- one feels heat leaving or entering one's body, depending on the current of the wind, it can cause heat to leave or enter your body at a quicker rate. "
] | [
"false presupposition"
] | [
"The temperature sometimes feels cooler or warmer than it actually is.",
"The temperature sometimes feels cooler or warmer than it actually is."
] | [
"false presupposition",
"normal"
] | [
"One doesn't really feel temperature- one feels heat leaving or entering one's body, depending on the current of the wind, it can cause heat to leave or enter your body at a quicker rate. ",
"One doesn't really feel temperature- one feels heat leaving or entering one's body."
] |
2018-21119 | Why do airlines have ashtrays in the toilets when you can’t smoke ? | Quoting this fantastic comment posted by /u/pixel_of_moral_decay in [this thread a few weeks ago]( URL_0 ) > The ashtray is actually one of my favorite engineering bits on an airplane. > The design parameters for aviation all center around one thing: redundancy. If something fails, you don't want it to cause a problem. That's why planes are designed to be able to fly if an engine fails (ETOPS), there's secondary hydraulics (you'll lose functionality, but not enough to crash), there's secondary everything. Landing gear doesn't deploy? It can drop with gravity. Electrical goes out? Ram Air Turbine (RAT)! Every thing critical to flight and safety has an alternative. You're effectively flying a plane inside a plane, but don't realize it. > The ashtray follows that engineering mantra perfectly. The primary method of avoiding fire is to not have cigarettes and open flames in the cabin. The secondary method is to not have flammable materials in the cabin when possible and things like an ashtray, so if someone does light up, there's less of a risk of them causing a fire (like dropping it in the trash with all the tissues). There's also smoke detectors for early detection and fire extinguishers. > Even something as mundane as a no smoking policy is engineered with the thinking "what if our primary defense doesn't work?" > Brilliant when you think about it. Even the smallest detail like that is thought about, and the solution is simplistic, which is the best kind of solution for an engineering problem when safety is involved. > That's why an airline can't take off without an ashtray in the lavatory. They will actually delay a flight over it. It's a redundancy and another thing to make flying safer. | [
"The presence of an ashtray is sometimes commented upon, given that smoking has been long banned on flights in many parts of the world. However it is a requirement of the Federal Aviation Administration that ashtrays continue to be fitted to the doors of aircraft toilets, due to the fire risk caused by the possible... | [
"It is not logical to have an ash tray in an airplane's bathroom when you can't smoke on the plane."
] | [
"The ashtray is a safety redundancy just in case someone does decide to light up in the bathroom."
] | [
"false presupposition"
] | [
"It is not logical to have an ash tray in an airplane's bathroom when you can't smoke on the plane.",
"It is not logical to have an ash tray in an airplane's bathroom when you can't smoke on the plane."
] | [
"false presupposition",
"normal"
] | [
"The ashtray is a safety redundancy just in case someone does decide to light up in the bathroom.",
"The ashtray is a safety redundancy just in case someone does decide to light up in the bathroom."
] |
2018-01884 | why does speed affect the turning radius of a car? | it doesn't. turning radius is a mechanical angle of front wheel and distance between front wheel and rear wheel. due to speed, you may not be able to achieve that turning radius at speed because the mass of the car exceeds capabilities of friction of the rubber tires on ground. that's more of a skid pad result, not a turning radius. | [
"A notable exception in this description is of vehicles that are capable of spinning around their central axis, such as certain lawnmowers and wheelchairs as they do not follow a circular path as they turn. In this case the vehicle is referred to as a \"zero turning radius\" vehicle.\n\nSome camera dollies used in ... | [
"Speed affects the turning radius of a car.",
"Speed affects the turning radius of a car. "
] | [
"Turning radius is affected by the angle of front wheel and the distance between front wheel and rear wheel.",
"Speed does not affect the turning radius of a car."
] | [
"false presupposition"
] | [
"Speed affects the turning radius of a car.",
"Speed affects the turning radius of a car. "
] | [
"false presupposition",
"false presupposition"
] | [
"Turning radius is affected by the angle of front wheel and the distance between front wheel and rear wheel.",
"Speed does not affect the turning radius of a car."
] |
2018-03103 | Why does skin turn blue/purple when you get hurt | Bruising. Your tissue is filled with blood from broken vessels. If you look at someone with pale skin, they should have some blush, reddish hue in certain places, or even blue streaks where their larger blood vessels are. Bruising causes that blood to leak into the surrounding tissue, which shows through your skin. The same thing happens when you break a blood vessel in your eye, but it's much more red as it's close to the surface. Bruising may also turn yellow as the body breaks down the clotted blood and clears it out from the surrounding tissue. | [
"There are at least five different pigments that determine the color of the skin. These pigments are present at different levels and places.\n\nBULLET::::- Melanin: It is brown in color and present in the basal layer of the epidermis.\n\nBULLET::::- Melanoid: It resembles melanin but is present diffusely throughout... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-10891 | Why is it that sometimes when someone tells me to do something I was about to do, I really don't want to do it anymore? | Most people like their autonomy, but it’s also kind of demeaning when it happens a lot or is something obvious that needs to be done, like the person doesn’t know. | [
"Even if the need to change course or cease action is recognized, communication speed, policies, and business politics can be hindrances. A larger organization, especially one with a spread of subgroups, has to communicate the argument and decision to go against previous actions across the appropriate levels. If th... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-01829 | Why doesn’t cooking something at a high temperature for a short amount of time not produce the same results as cooking something at a lower temperature for a longer amount of time? | Food is cooked through heat radiation. Each minute it's in the oven, the heat radiates further in. The idea is to bring the temp up throughout the meat/cookies/cake. Too much heat too fast will burn the outside before it reaches the inside. Heat can only radiate so fast. | [
"The use of temperatures much lower than for conventional cooking is an equally essential feature of sous-vide, resulting in much higher succulence at these lower temperatures, as cell walls in plant-based food do not burst. In the case of meat cooking, tough collagen in connective tissue can be hydrolysed into gel... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-00223 | Why is that sometimes when I’m sharpening a pencil with an electric sharpener, it gets really sharp but if you push the tip in one direction even slightly the graphite tip falls out? Then no matter how many times I resharpen it, it won’t sharpen correctly. | It's possible you may have dropped the pencil. When you drop a pencil (especially colored pencils, funny enough), the graphite can shatter. Now you have a long tube full of broken graphite pieces that easily break off once they've been exposed by the sharpener. Source: My high school art teacher. She flipped her wig any time she heard a pencil drop. | [
"An artist's or draftsman's pencil sharpener leaves the graphite untouched and sharpens only the wood (some models can switch from standard to wood-only by an adjustment). The graphite lead is then honed to a sharp point with a lead pointer, which sharpens only the lead without wood. Lead pointers are also used wit... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-00424 | Why does the iPhone 8’s home button only press down when pressed with a finger? | I believe it doesn't actually press even with a finger. There's just a taptic response so it FEELS like it pressed. When you have a cloth over it the button doesn't respond so no response. | [
"Directly above the volume controls is a ring/silent switch that when engaged mutes telephone ringing, alert sounds from new & sent emails, text messages, and other push notifications, camera shutter sounds, Voice Memo sound effects, phone lock/unlock sounds, keyboard clicks, and spoken auto-corrections. This switc... | [
"Iphone home button gets pressed down with finger."
] | [
"There is no button to press down it is just a haptic response to make it feel like there was. "
] | [
"false presupposition"
] | [
"Iphone home button gets pressed down with finger."
] | [
"false presupposition"
] | [
"There is no button to press down it is just a haptic response to make it feel like there was. "
] |
2018-02009 | why if you hang upside down your blood all goes to your head and it hurts, but when you're right side up the blood doesn't all go into your feet and they feel fine? | We evolved to stand upright. So our veins have one-way valves in them that prevent blood from flowing back down toward our feet. But we don't have any such valves to prevent flow in the other direction, because there was no survival pressure for them to evolve. | [
"Section::::Positions.\n\nBULLET::::- Supine position: The most common surgical position. The patient lies with back flat on operating room bed.\n\nBULLET::::- Trendelenburg position: Same as supine position but the upper torso is lowered.\n\nBULLET::::- Reverse Trendelenburg position: Same as supine but upper tors... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-02846 | Why do white supremisists adopt the Nazi Swastika and Hitler himself as symbolic of their beliefs when none of them would pass Nazi "racial purity" standards? | You're absolutely correct. However the rise of white supremacy doesn't start off targeting EVERYONE who isn't "pure" rather it starts with obvious targets. Then slowly moves in to a narrower and narrower definition. First they target those who are obviously non-white, then the religions that are "not white" then the religions who stood against them, then the groups that didn't actively support them, then it becomes those who supported them but think differently because they "might" betray them, it just gets narrower and narrower until the staunch supporters realize that they are next. | [
"When Hitler created a flag for the Nazi Party, he sought to incorporate both the Hakenkreuz and \"those revered colors expressive of our homage to the glorious past and which once brought so much honor to the German nation\". (Red, white, and black were the colors of the flag of the old German Empire.) He also sta... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04688 | Why do scientists try to find oxygen to find life on other planets? Aren´t other forms of life-based on other chemical elements possible? | Usually we're looking for water, not oxygen. And this is because all life on Earth as we know it requires water, and since this is our only example of actual life, we are looking for similar conditions elsewhere. Is it *possible*? Sure. But we don't know if it actually happens/exists so we're looking for signs based on what we DO know. | [
"Hypothetical types of biochemistry are forms of biochemistry speculated to be scientifically viable but not proven to exist at this time. The kinds of living organisms currently known on Earth all use carbon compounds for basic structural and metabolic functions, water as a solvent, and DNA or RNA to define and co... | [
"Scientists try to look for signs of life in the universe by detecting oxygen.",
"We are looking for oxygen to find life."
] | [
"Scientists look for water on other planets because they use the fact that life on earth needs water for reference.",
"We are looking for water to find life. "
] | [
"false presupposition"
] | [
"Scientists try to look for signs of life in the universe by detecting oxygen.",
"We are looking for oxygen to find life."
] | [
"false presupposition",
"false presupposition"
] | [
"Scientists look for water on other planets because they use the fact that life on earth needs water for reference.",
"We are looking for water to find life. "
] |
2018-08116 | Why is it that we have a single packet of food that can give all the required nutrition to sustain our pets, but we can't do the same for humans? | You can do the same for humans and a few companies have tried over the years, but humans are easily bored and don't like eating nutrient paste for every meal. Your dog doesn't really get a choice. | [
"In 2015, an estimated 77.8 million dogs and 85.6 millions cats were living in the USA. The consumer desire to feed their pets premium foods which advertise healthy and human-grade ingredients coupled with the increasing prevalence of pet ownership is causing increased pressure on the meat industry which could resu... | [
"There isn't a single packet of food that gives required nutrition to humans."
] | [
"Companies have made food packets, but humans prefer variety."
] | [
"false presupposition"
] | [
"There isn't a single packet of food that gives required nutrition to humans.",
"There isn't a single packet of food that gives required nutrition to humans."
] | [
"normal",
"false presupposition"
] | [
"Companies have made food packets, but humans prefer variety.",
"Companies have made food packets, but humans prefer variety."
] |
2018-05058 | Why is our stomach "in knots" when we are stressed out or worried? | There are several things. Your guts is has the [vagus nerve]( URL_0 ) going from your brain to your guts. Therefore, some psychological issues can affect your digestive system. Like a headache can cause vomiting (it's not the only cause of vomiting, however). The other thing is the [sympathetic nervous sytem]( URL_1 ). The sympathetic nervous system is responsible for fight-or-flight response, which causes changes in your guts to facilitate your ability to fight or run. When you're stressed or worried, you're at a heightened state of mind (you're in the fight-or-flight mode), therefore, your sympathetic system is active. | [
"\"Psychosomatic disease states in monkeys and the limbic system\" was the result of Foltz’ investigation of chaired \"executive\" monkeys. They were trained to conditioned avoidance and \"conditioned stress,\" and monitored as to agitate states by the degree of lever pulling and the effect on intestinal motility (... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-10585 | Why is sweating profusely our body’s go to defense when battling nervousness? | Stress response activates our sympathetic Nervous system (Fight or Flight response) and since we evolved to deal with stress by killing or running, it is trying to pre-cool our body in anticipation of combat or running. Our other major autonomic (largely operating without our conscious control) nervous system is our parasympathetic nervous system (feed and breed, or rest and digest system). Basically, our stress response system didn't evolve to deal with "do you think that hot chick will say yes if I ask her out" and "Does my boss hate me" and the other major causes of stress in our modern life. If you want a complete rundown of this topic, I can recommend a book "Why zebras don't get Ulcers" by Dr Robert Sapolsky. Essentially, our autonomic nervous system didn't evolve to deal with the stresses of modern living, and it causes lots of problems in our life. Edit: Made a mistake in the book title. | [
"Although sweating is found in a wide variety of mammals, relatively few (exceptions include humans and horses) produce large amounts of sweat in order to cool down.\n\nSection::::Definitions.\n\nBULLET::::- The words diaphoresis and hidrosis both can mean either perspiration (in which sense they are synonymous wit... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-11758 | Are batteries heavier when fully charged? Why/why not? | No. Batteries don't give out charge, per se, to power electronics. They generate a potential difference, causing electrons to flow through a circuit. A charged battery doesn't hold extra charge, it provides a voltage source by separating charges inside it. It dies when those charges slowly disperse, causing the voltage they generate to drop. | [
"Battery discharge profiles are often described in terms of a factor of battery capacity. For example, a battery with a nominal capacity quoted in ampere-hours (Ah) at a C/10 rated discharge current (derived in amperes) may safely provide a higher discharge current – and therefore higher power-to-weight ratio – but... | [
"Batteries give out a charge. "
] | [
"Batteries actually provide a voltage source that separates charges contained within the battery."
] | [
"false presupposition"
] | [
"Batteries give out a charge. ",
"Batteries give out a charge. "
] | [
"normal",
"false presupposition"
] | [
"Batteries actually provide a voltage source that separates charges contained within the battery.",
"Batteries actually provide a voltage source that separates charges contained within the battery."
] |
2018-01191 | Why is it much easier to reverse a car into a tight parking space than drive it in forwards? | It's much easier to reverse into a carspace where room is limited than it is to drive straight in. The reason for this is that the back wheels are fixed in direction in relation to the car. This effectively makes the pivot point of the car the middle of the rear axle. | [
"In the 1950s, General Motors automobiles with automatic transmissions placed the R for reverse at the furthest clockwise position in the rotation of the column-mounted shift lever. L for low position was just adjacent as one would move the lever one notch counterclockwise. Because it was very easy to select L, a f... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-22331 | how do we know about different things on planets (water, air, heat, etc.)? | It depends on the planet, but for most things we can tell just by looking. For Mars we have all those robots that are driving around the planet and taking samples that they analyze, but mostly we are reduced to just looking at things from afar. Fortunately for us, understanding physics and chemistry means that we can tell a whole lot about things just by looking at them. The light (and other types of radiation) that comes to us from an object contains a wealth of information. Different elements absorb and emit light on different very specific wavelength (this is what gives things color). So we can look at something far away and learn things about its chemical composition. Looking at things in the infrared spectrum tells us about its temperature. Tracking how stuff moves in orbits around other stuff gives us clues about the mass of the objects and seeing just how big something is tells us about its volume, though which we can calculate density. There is a lot more than that and in practice it involves a bit more than just looking, but the simple and eli5 answer is that for most distant objects looking is all we can do, so that is what we do and make the most of it. | [
"a civilization heat signature should be within a \"comfortable\" temperature range, like terrestrial urban heat islands, i.e. only a few degrees warmer than the planet itself. In contrast, such natural sources as wild fires, volcanoes, etc. are significantly hotter, so they will be well distinguished by their maxi... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-14971 | Why are cans more recyclable than plastic bottles? | Plastics are made of polymer chains that are tangled up. It's like a big mess of spaghetti. For most plastics, when you recycle it you'll end up breaking down some of those chains. If you keep recycling it you'll get rice which behaves quite different from spaghetti, and finally couscous which is even weaker. Many plastics become a worse form of plastic when reprocessed which limits what you can do. You'd also need to perfectly sort them to get great recyclability Aluminum and iron don't break down in the recycling process. You just heat them up until you've got pure aluminum or iron again and then add in the impurities that you need to make your alloy. When you're done, you can heat it again and make a different alloy. Metals are particles that form crystals with each other rather than long interlocking chains that break down | [
"Cans can be made with easy open features. Some cans have screw caps for pouring liquids and resealing. Some have hinged covers or slip-on covers for easy access. Paint cans often have a removable plug on the top for access and for reclosing.\n\nSection::::Recycling.\n\nSteel from cans and other sources is the most... | [
"Recycling plastic should be easier than recycling cans.",
"Recycling plastic should be easier than recycling cans."
] | [
"Recycling plastic shortens polymer chains, which degrades the quality of the plastic, but metal cans can be melted back down to their elemental metal.",
"Recycling plastic shortens polymer chains, which degrades the quality of the plastic, but metal cans can be melted back down to their elemental metal."
] | [
"false presupposition"
] | [
"Recycling plastic should be easier than recycling cans.",
"Recycling plastic should be easier than recycling cans.",
"Recycling plastic is similar to recycling metal"
] | [
"false presupposition",
"normal"
] | [
"Recycling plastic shortens polymer chains, which degrades the quality of the plastic, but metal cans can be melted back down to their elemental metal.",
"Recycling plastic shortens polymer chains, which degrades the quality of the plastic, but metal cans can be melted back down to their elemental metal.",
"Rec... |
2018-14091 | How far do you have to get in science or math to be working on modern day questions that are still unsolved? | In the very broad strokes, your Bachelors and Masters degrees are spent proving your mastery of the material. Your Masters thesis may require you to analyze prior research in a way that may contribute to the knowledge base. Your doctoral thesis, however, is expected to expand the knowledge base in your field and generally must be original research. | [
"The Mystery Hunt was started in 1981 by then-graduate student Brad Schaefer. The first Hunt consisted of 12 subclues on a single sheet of paper including a Vigenere cipher, a short runaround, and an integral. The answers to the subclues detailed the location of an Indian Head penny hidden on campus. The individual... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-23769 | When you have a cold/your nose is stuffed, and then suddenly it feels like an air bubble appears and clears your nose so you can breathe again. What's happening? | Actually it is your turbinates swelling or shrinking. Turbinates are “erectile” tissue in your nose that fill with blood and block off airflow. When they swell or shrink it feels funny. This is how instant nasal decongestants like Afrin work. They contain a chemical that causes the blood vessels to constrict which shrink the turbinates. | [
"Sinusitis (or rhinosinusitis) is defined as an inflammation of the mucous membrane that lines the paranasal sinuses and is classified chronologically into several categories:\n\nBULLET::::- Acute sinusitis – A new infection that may last up to four weeks and can be subdivided symptomatically into severe and non-se... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-01570 | Why is there a little wall in the gas container of a lighter? | A longer, thinner cylinder is stronger than a shorter, fatter one. Alas, the short, fat shape is more desirable in a lighter. The result is that a long, thin cylinder is folded in half to get the desired strength in the desired shape. | [
"A metal enclosure with air holes generally surrounds the flame, and is designed to allow mixing of fuel and air while making the lighter less sensitive to wind. The high energy jet in butane lighters allows mixing to be accomplished by using Bernoulli's principle, so that the air hole(s) in this type tend to be mu... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-08287 | What are the contributing reasons why the many different countries that comprise Africa have not become first-world countries, or rose up to have a helpful government that took good care of its people? | 1. Africans lagged behind the rest of the world politically, socially, and economically. They did have their own kings and chiefs but not well- organized states like Europeans. Europeans have had thousands of years to establish national identities. 2. National boundaries in Africa are arbitrary and group together hostile ethnic groups into a single country. Most people blame the Europeans for this. If you look at a map of Africa it is clearly impossible to draw national boundaries that would actually make sense, but the Africans probably should have been given the right to figure that out for themselves. Anyway, it’s hard to hold a country together when different regions have diametrically opposite cultures. 3. Europeans set a really, really, really bad example. Instead of demonstrating how government could help the people, they shamelessly robbed the place and enslaved the population. Government in Africa’s sole function was to steal as much as possible to make Europeans rich. Small wonder African leaders now do the same thing. 4. Scarcity. Finally, something we can’t blame on Europeans! The fact is that Africa just doesn’t have much in the way of natural resources. They have some diamonds and precious metals, but little else of value. Europeans who were late to the colonization game claimed their territory and then realized Africa was nowhere near as lucrative as somewhere like India. Anyway, when you are poor survival becomes the name of the game, so it is little surprise that people fight each other over resources. (And those places that do have natural resources, like the Congo, turn into war zones.) 5. Geography works against many African countries. Big parts of the continent are landlocked. In Europe, practically everyone is close to the sea or a major river. In America, the Mississippi River basin made it very easy to travel into the interior and back. Africa has no such river system. For example, it would be very easy to travel into the interior on the Nile, except for the cataracts that make it unnavigable. 6. The Europeans... Again. After WW2 European powers gave up on African colonialism, and the withdrawal was not pretty. One good example is the French. When former colonies asked for independence, they did not help the Africans transition to functioning self-governance. Instead, they took everything that wasn’t nailed down, even going so far as to rip out telephone wires and break the glass in buildings. It was a very spiteful ‘we’re-taking-our-toys-and-going-home’ kind of tantrum. Not only did this leave the Africans without the infrastructure they needed to govern, but it demonstrated that when there’s a political outcome you don’t like, the proper response is violent rage. Not a good role model to follow, but that hasn’t stopped the Africans from emulating them. Additionally: There are two exceptions to the above. The first is Saharan Africa, which is on the Mediterranean and populated mostly by Arabs. Generalizations about Sub-Saharan Africa do not apply to the Northern region, which is politically, economically, and ethnically much different. The other exception is South Africa, where Europeans colonized and never left. To this day, South Africa is not exactly a pleasant place but it has been far more stable at the macro level than other African countries. | [
"countries have been acting based on their own personal interests. It was during the late 1800s that the western world really started to explore deeper into the heart of Africa. What the explorers found was an abundance of land and resources. The only thing standing in their way was a group of primitive people with... | [
"No African countries became first-world countries with helpful governments. "
] | [
"Most African countries have not become first-world countries with helpful government, with two exceptions, Sub-Saharan Africa and South Africa."
] | [
"false presupposition"
] | [
"No African countries became first-world countries with helpful governments. ",
"No African countries became first-world countries with helpful governments. "
] | [
"false presupposition",
"normal"
] | [
"Most African countries have not become first-world countries with helpful government, with two exceptions, Sub-Saharan Africa and South Africa.",
"Most African countries have not become first-world countries with helpful government, with two exceptions, Sub-Saharan Africa and South Africa."
] |
2018-15635 | Why do children have a tendency to smile so much more than adults ? | Because children’s brains are literally tripping all the time . The world is still met with awe and wonder and everything is new . As you develop, our brains start operating in a different mode cycling through “priors” or past experiences and using those as templates for subconscious decision making . | [
"People are also relatively good at determining if a smile is real or fake. A recent study looked at individuals judging forced and genuine smiles. While young and elderly participants equally could tell the difference for smiling young people, the \"older adult participants outperformed young adult participants in... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-13696 | why do girls (generally) have neater and more appealing handwriting than those of boys? | Girls and boys develop their accurate muscle movements at different times. However they are taught how to write at the same time. Boys accurate muscle movement develops later so when they learn to write they can't physically write as neatly or have to work a lot harder in order to do so. | [
"Sometimes children need some assistance when developing their fine motor skills. This requires one to find strategies to assist children with their development. Occupational therapists are experts in the field of fine motor and handwriting development. More exposure to physical activity is known to be the most eff... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04397 | What causes the wind to howl? | It not the wind by itself, but rather the wind blowing past an object be it trees, lightposts, edges of your roof. I was amazed how quiet skydiving was once the chute opens. The only sound you hear is the air in the chute itself. Very peaceful. | [
"\"I Felt Like A Gringo\" is an autobiographical song written by Watt about a day trip Minutemen took in Mexico on the 4th July, 1982. There was an election that day for President of Mexico, which was referenced in the lyric \"\"Who won,\" I said, \"the election?\"\" (the winner in question was Miguel de la Madrid)... | [
"Wind makes a howling sound.",
"The wind howls. "
] | [
"It is the wind hitting objects that makes the sound.",
"The wind does not howl, however the objects the wind blows by causes it to howl."
] | [
"false presupposition"
] | [
"Wind makes a howling sound.",
"The wind howls. "
] | [
"false presupposition",
"false presupposition"
] | [
"It is the wind hitting objects that makes the sound.",
"The wind does not howl, however the objects the wind blows by causes it to howl."
] |
2018-02875 | Why are the savings account interest rates so abysmally low in the US? | Because the Federal Reserve has set the government's rate for lending money to banks very low. That means that banks can't afford to pay you more than they pay the government, or they would lose money, because your terms are not as generous as the governments (like you want to be able to withdraw the money). | [
"The advent of Internet banking at the end of the 20th century saw a new phase in savings banks with the online savings bank that paid higher levels of interest in return for clients only having access over the web.\n\nSection::::History.\n\nIn Europe, savings banks originated in the 19th or sometimes even the 18th... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-02610 | What would happen if i just ate peanut butter and jam sandwiches for the rest of my life? | you'll survive, you'll be fine, you just won't be particularly healthy. if you take a multivitamin and you're otherwise young and healthy you'll be fine. i'd try to add some calcium in there at some point, though. | [
"Section::::Nutrition.\n\nA peanut butter and jelly sandwich made with white bread, two tablespoons each of peanut butter and strawberry jelly, provides 403 kcal, 18 g fat, 58 g carbs and 12 g protein which is 27% of the Recommended Daily Intake of fat and 22% of calories.\n\nWhile roughly 50% of the calories are f... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-00647 | Why are some websites browser specific, if their underlying code is based on a standardization, supported by most browsers (Google Earth on FF)? | There are some specific tags that only specific browsers understand, there was a fair amount of Internet Explorer specific HTML and CSS years ago that wasn't part of the standard but IE implemented it. Other times you're relying on different implementations having different quirks, you made your page work with IE which uses a slightly off standard look and now it doesn't work with Firefox which uses a slightly different off standard way Now you're likely to run into things like ActiveX that need Internet Explorer to be able to run because its coupled tightly with windows. Its rather uncommon to find something that works in Firefox that doesn't work in Chrome. Google stuff generally works with every browser(can't risk losing customers!) | [
"Microsoft contacted the Web Standards Project and experts on Web standards and asked for assistance in devising a new DOCTYPE-like technique that could work across browsers and let Web developers specify exact browser versions under which their Web sites are known to work correctly, and browsers implementing this ... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-03501 | Why is it that when people are alone for a long time, they go insane? | I don't think that's universally true. There are many people that spend very long periods in isolation and don't go insane. They probably lose a lot of their social skills, but that doesn't equal insanity. I think the important part is being able to keep your mind occupied and stimulated. If you're trapped in an empty room for a long time, then yeah you'll probably lose it a lot faster than someone who just lives by themselves with no human contact. | [
"Ryan J. Pardo of \"Paste\" gave the album a score of 7.7 out of 10 and wrote, \"The whole album is awash in swaths of watery shimmer, as if recorded underwater.\" Giving the album a score of 7.4, \"Pitchfork\" writer Sasha Geffen felt the \"varied taxonomy of the band gels together as they relay the psychological ... | [
"People go insane after being alone for a long time."
] | [
"Not all people go insane after being alone for a long time."
] | [
"false presupposition"
] | [
"People go insane after being alone for a long time."
] | [
"false presupposition"
] | [
"Not all people go insane after being alone for a long time."
] |
2018-02448 | Why are award shows and big sports games such as the Super Bowl on Sunday nights? | I think the tv viewing audience is bigger on a Sunday night, because more people are at home in preparation for going to work the next day, whereas people go out and do stuff on Saturdays. | [
"BULLET::::- Saturday nights: Until the 1990s, many popular series aired on Saturdays, including CBS series such as \"Have Gun - Will Travel\", \" All in the Family\", \"The Mary Tyler Moore Show\", \"The Bob Newhart Show\", \"The Carol Burnett Show\", \"Dr. Quinn, Medicine Woman\", \"Early Edition\" and \"Walker, ... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-03515 | Why is Columbus Ohio shaped the way it is? | That's not terribly unusual for any large city. Typically the largest city in an area started out just one of many smaller cities. It grows faster than the either, and either annexes its neighbors or if they don't want to be annexed, grows around them. | [
"Section::::Transportation.:Rail.\n",
"Section::::Transportation.:Airports.\n",
"BULLET::::- United States Declaration of Independence, July 4, 1776\n\nBULLET::::- Treaty of Paris, September 3, 1783\n\nBULLET::::- Unorganized territory of the United States, 1783–1787\n\nBULLET::::- Northwest Indian War, 1785–17... | [
"Columbus, Ohio is shaped strangely."
] | [
"Large cities grow by annexing their neighbors or growing around them."
] | [
"false presupposition"
] | [
"Columbus, Ohio is shaped strangely."
] | [
"false presupposition"
] | [
"Large cities grow by annexing their neighbors or growing around them."
] |
2018-13617 | Why is it so hard to fold/crease the type of foil that potato chip bags come in, compared to normal paper or aluminum foil? | Potato chip bags are usually a metalized piece of plastic which is a very thin film of aluminum deposited on a thin plastic film. This means it will have more of the characteristics of plastic for folding. Normal aluminum foil is a generally mostly aluminum, and no plastic. Aluminum as a sheet has characteristics which allow sharp creases like paper. | [
"Wrapping the potato in aluminium foil before cooking in a standard oven will help to retain moisture, while leaving it unwrapped will result in a crisp skin. When cooking over an open fire or in the coals of a barbecue, it may require wrapping in foil to prevent burning of the skin. A potato buried directly in coa... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-00163 | At what point does a knife become a sword? | The transitions are a bit muddy and have shifted through history but a dagger is a double edged knife, a dirk is a dagger that is 6"-12" and a short sword is 1'-2' in length. Then you have numerous kinds of longer swords. But the answer to your question is 1'. | [
"Section::::Classification by blade type.:Double-edge and straight swords.:Long knife and short sword.\n\nKnives such as the seax and other blades of similar length – between 1 and 2 feet (~ 30 cm and 60 cm) – are sometimes construed as \"swords\". This is especially the case for weapons from antiquity, made before... | [] | [] | [
"normal"
] | [
"There is a distinct difference between a knife and a sword."
] | [
"false presupposition",
"normal"
] | [
"The transition from knife to sword is a bit muddy."
] |
2018-08838 | Why are most metals other than gold and copper, silver in color? | Well a lot of metals, when hit with photons (particles of light) go through an energy change. The electrons go through an energy change and go from one energy level to another. In order to do this only the strongest photon waves are absorbed, therefore it reflects some minor amount of light that weren't strong enough. Waves of color are absorbed so there is no color reflected, just light. We refer to this colorless reflection as silver. Gold and copper each have their own explanation as to why they are different. Gold also goes through an energy shift, but I stead of going from energy level 2 to level 3, it goes from 1 to 2. When the shift from 2 to 3 happens it absorbs all light and. When the shift from 1 to 2 happens, blue light is absorbed, reflected a goldish light. I looked into this a long time ago so I don't remember specific terms, but it's very common for metals to go through a 2 to 3 energy shift because of how their electrons are placed and how many they have. It is important to not that metal alloys can be found in nature that can have bright red, yellow, and green colors so that may help. Sorry for any formatting issues, I am on mobile. I hope that helped! | [
"\"Roman silver\", a blue-gray tone of silver, is one of the colors on the Resene Color List, a color list widely popular in Australia and New Zealand.\n\nSection::::Variations of silver.:Old silver.\n\nAt right is displayed the color old silver.\n\n\"Old silver\" is a color that was formulated to resemble tarnishe... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-00012 | Why does eating something sweet make other less sweeter things taste not sweet? | You can actually tire out the nerve cells in your tongue, by overstimulating them temporarily with a particular taste. | [
"The ability to taste sweetness often atrophies genetically in species of carnivores who do not eat sweet foods like fruits, including bottlenose dolphins, sea lions, spotted hyenas and fossas.\n\nSection::::Sweet receptor pathway.\n",
"Sweetness\n\nSweetness is a basic taste most commonly perceived when eating f... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-14618 | In school we learnt that honey doesn't spoil. So how is it that packaged honey, even those that claim to be "pure", have an expiration date? | They don’t spoil but they do lose flavour, smell and water. If you store honey in fridge, some times you might notice it crystallises. This will happen in room temperature after a couple of years. So the expiration date is really a best by date. | [
"It should be acknowledged that a durable life date is NOT an indicator of food safety. Once something is opened, depending on how it is stored, the shelf life can change. For example, an open box of crackers meant to expire in two weeks, will expire much faster should the seal be left open after each use.\n\nSecti... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-07032 | why do some tend to feel hotter than others in the same climatic conditions? Others also claim to feel colder. How does this work when our healthy body temperature is all the same? | Different metabolic rates, different people are used to different temperatures. Also varying amounts of body fat is a contributing factor. | [
"Section::::Resiliency mechanisms.:Social resources and health-promoting behaviour.\n",
"Several investigations have found hardiness and physical exercise to be uncorrelated. On the other hand, one study examined a broader array of health-protective behaviours, including exercise, and found that hardiness worked ... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-00838 | If the theory that the Moon is created from asteroid and Earth collision, why does the Moon reflect sunlight and the Earth doesn't? | The earth does reflect sunlight! How do you think astronauts take all those [nice pictures of earth from space]( URL_0 )? | [
"Features on Earth, the Moon, and some other bodies have, to some extent, retroreflective properties. Light striking them is backscattered, or diffusely reflected preferentially back in the direction from which it has come rather than in other directions. If the light comes from the Sun, it is reflected preferentia... | [
"The Earth does not reflect sunlight.",
"If the moon and the earth were created from a collision of an asteroid and the Earth, the Earth should reflect sunlight just like the moon. "
] | [
"The Earth reflects sunlight.",
"The Earth actually does reflect sunlight. "
] | [
"false presupposition"
] | [
"The Earth does not reflect sunlight.",
"If the moon and the earth were created from a collision of an asteroid and the Earth, the Earth should reflect sunlight just like the moon. "
] | [
"false presupposition",
"false presupposition"
] | [
"The Earth reflects sunlight.",
"The Earth actually does reflect sunlight. "
] |
2018-04927 | why your lips get chapped. I’ve always thought it was from your lips being dry and also has something to do with cold air. If they get chapped from being dry, why wouldn’t adding water to keep your lips moist solve the problem? | Just adding moisture to your lips doesn't last. Our skin has oils in it to prevent evaporation and water loss (and help resist obsorbing too much water) and dry lips also lose these skin oils. An oily or waxy substance will help lips retain moisture as opposed to a watery substance which will make them wet briefly. And of course lip balms are waxy substances for this purpose. | [
"The primary purpose of lip balm is to provide an occlusive layer on the lip surface to seal moisture in lips and protect them from external exposure. Dry air, cold temperatures, and wind all have a drying effect on skin by drawing moisture away from the body. Lips are particularly vulnerable because the skin is so... | [
"Adding moisture to lips should prevent them from being chapped.",
"Adding water to lips would be enough to keep lips moist."
] | [
"Lips get chapped due to excessive loss of moisture. Saliva or water hastens this process by removing the oil layer on skin that protects lips from water loss. ",
"Adding water to the skin won't last, it would only make them wet briefly."
] | [
"false presupposition"
] | [
"Adding moisture to lips should prevent them from being chapped.",
"Adding water to lips would be enough to keep lips moist."
] | [
"false presupposition",
"false presupposition"
] | [
"Lips get chapped due to excessive loss of moisture. Saliva or water hastens this process by removing the oil layer on skin that protects lips from water loss. ",
"Adding water to the skin won't last, it would only make them wet briefly."
] |
2018-16530 | Why do ancient Greek sculptures have such small penises? | At the time, large male members were considered primitive / uncultured / barbarian in nature. | [
"The ancient Greeks believed that small penises were ideal. Scholars believe that most ancient Greeks probably had roughly the same size penises as most other Europeans, but Greek artistic portrayals of handsome youths show them with inordinately small, uncircumcised penises with disproportionately large foreskins,... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-07309 | how did pre industrial sailing ships move up to or move away from docks in a controlled manner? | If winds were not suitable for sailing right up to the docks, they would run a line (rope) between ship and dock, and then gradually pull it in. | [
"The earliest known description of a floating dock comes from a small Italian book printed in Venice in 1560, titled \"Descrittione dell'artifitiosa machina\". In the booklet, an unknown author asks for the privilege of using a new method for the salvaging of a grounded ship and then proceeds to describe and illust... | [] | [] | [
"normal"
] | [
"Sailing ships needed to be able to direct themselves into docks without external help before the Industrial Age."
] | [
"false presupposition",
"normal"
] | [
"Sailing ships could be pulled into dock using a rope system."
] |
2018-12016 | Why is it that when I'm trying to hold it in, the urge to #1/#2 comes in waves and not continuously? | It’s mostly because whenever you feel your bladder pressing, you have an urge to squeeze your PC muscles tightly. This stops the stream, but only temporarily. The waves you feel are your PC muscles loosening from the fatigue caused by holding in your pee for so long. As for your bowels, it’s your sphincter muscle doing the same thing. Unless you’re compromised in some way, your muscles won’t loosen completely. Older people have looser muscles which is why they have bowel and urinary incontinence. | [
"Urininary urgency may be as a result of anxiety or in some cases extended sexual arousal. When a human male is attracted to a mate, there is an autonomic nervous system response, and the body is therefore not entirely under conscious control, with many hormones including norepinephrine being released in the parasy... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-02246 | Why are the countries that make up Great Britain allowed to team up to compete in the Olympics as a single entity? | The real question is why they compete separately in other sports. Usually by the word "country" we mean a sovereign state. The UK is a sovereign state. The UK isn't particularly unusual as sovereign states go, except for the fact that it calls its constituent parts "countries". So the UK can be considered a country, or it can be considered a union of constituent countries. The Olympics *usually* has a team per sovereign state. Although there are many exceptions for dependent territories, the UK proper is not an exception (although it has dependent territories which are). Other sports like football are different. Although its still usually the case that there is one team per sovereign state, the UK is an exception because the sport originated in the UK. The first "international" football games were between the nations within the UK, so they've continued to compete separately. | [
"In international competition the constituent nations of Great Britain ordinarily compete as separate unions representing England, Scotland and Wales. Northern Irish players who normally represent Ireland would have been eligible however the IRFU insisted that they do not play for Great Britain. \n",
"In internat... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04759 | How doesn’t a drink fall out a straw when we press the top end with a finger? | For the drink to fall out, something else has to get in to occupy that space. Usually this will be air, but if you seal the top there's no way for air to enter. The drink can't fall out now because it would generate a vacuum inside the straw, and the negative pressure from that vacuum is much stronger then the miniscule weight of the drink. | [
"Inertia is seen when a bowling ball is pushed horizontally on a level, smooth surface, and continues in horizontal motion. This is quite distinct from its weight, which is the downwards gravitational force of the bowling ball one must counter when holding it off the floor. The weight of the bowling ball on the Moo... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-00711 | why haven’t we been to the moon again since 1969? | Because there is nothing up there. The Moon is a god forsaken hellscape that smells of gunpowder and Moon dust is so abrasive that it works its way through *kevlar* in no time. We haven't been back because it costs a lot of money to do something that gains nothing. | [
"The deaths of astronauts Gus Grissom, Ed White, and Roger B. Chaffee in the Apollo 1 fire on 27 January 1967 put a temporary hold on the U.S. space program, but afterward progress was steady, with the Apollo 8 crew (Frank Borman, Jim Lovell, William Anders) being the first manned mission to orbit another celestial... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04183 | Why do systems in the universe operate as flat plains? | Clumps of objects, like solar systems or galaxies, have a whole heap of motion. Each object within that system will have its own motion, but as a whole the system will have an overall average rotational motion. This rotational motion is effectively made up of the combined linear motion of the objects in two of the three dimensions, a 2D plane. As the system formed, objects within the system (eg rocks, dust, early planets etc), collide with each other, effectively cancelling out all the motion in the direction not encompassed by the overall rotation. This means that all the objects eventually end up constrained to the 2D plane of rotation, making it flat. Minutephysics has a great video talking about this far better than I can URL_0 | [
"One such observation is that of anisotropies (that is, variations with direction - see below) in the Cosmic Microwave Background (CMB) radiation. The CMB is electromagnetic radiation which fills the universe, left over from an early stage in its history when it was filled with photons and a hot, dense plasma. This... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-11249 | If the years we use in the modern calendar started with Christ, how come he was born on Dec the 25th, the last month, and not Jan 1st? | * Our current Gregorian calendar wasn't accepted until hundreds of years after Christianity became a thing. * Gregorian calendar wasn't started with or because of Christianity. It was meant to fix the problems with the Julian calendar so that seasonal changes and leap years could be taken into effect. The holiday that was taken into consideration was Easter, but this is a logistical change, and wasn't meant to center the calendar around Easter (which is a lunar-based holiday anyway). * Christ wasn't born on December 25th. He was probably born in springtime based on descriptions of constellations. December 25th is used because that was part of the old Saturnalia holiday honoring Saturn (Zeus), and the coming of the Sun (winter solstice, when days start getting longer). The Roman Empire wanted to convert people to Christianity, so they just took existing pagan holidays and renamed them to Christian holidays, but left the dates the same. | [
"The era based on the Incarnation of Christ was introduced by Dionysius Exiguus in 525 and is in continued use with various reforms and derivations. The distinction between the Incarnation being the conception or the Nativity of Jesus was not drawn until the late ninth century. The beginning of the numbered year va... | [
"Times started with Jesus Christ, so his birthday should be Jan 1st and not Dec 25th.",
"Christ was born on December 25th."
] | [
"Due to differences in calendars created in the past, and calendars created today, a misconception has been created. Jesus Christ was not born on Dec 25th in previous calendars.",
"Christ was probably born in springtime, based on descriptions of constellations."
] | [
"false presupposition"
] | [
"Times started with Jesus Christ, so his birthday should be Jan 1st and not Dec 25th.",
"Christ was born on December 25th."
] | [
"false presupposition",
"false presupposition"
] | [
"Due to differences in calendars created in the past, and calendars created today, a misconception has been created. Jesus Christ was not born on Dec 25th in previous calendars.",
"Christ was probably born in springtime, based on descriptions of constellations."
] |
2018-06350 | what is the difference between REST & SOAP web services? | A SOAP web service has a very structured request and response. Data types, required fields, etc., are all defined in a WSDL that you can consume with your application to automatically build the entire request structure. All of it goes over HTTP POST methods. The entire web service has a single endpoint that covers many methods. A RESTful web service is a more open concept that uses the raw HTTP data fields in the request to pass parameters. It also uses the HTTP methods (GET, POST, PUT, DELETE) to handle things differently. The URL is also part of your parameters, as that handles part of the function routing. (i.e., URL_1 would be expected to do stuff about inventory 12345, but URL_0 would be doing stuff about Customer 12345). The URL can also contain mandatory variables, such as those key ID fields. | [
"Representational state transfer\n\nRepresentational State Transfer (REST) is a software architectural style that defines a set of constraints to be used for creating Web services. Web services that conform to the REST architectural style, called \"RESTful\" Web services (RWS), provide interoperability between comp... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-02165 | why don’t you hear about the history of Africa before colonialism? | Egypt is one of the oldest civilizations on the planet and we hear a lot about them and their history prior to European colonial era. We also hear a lot about the Caliphate eras of the middle ages and dark ages which controlled much of North and Central Africa, and of Carthage that was in North Africa during the Roman era. But you are correct that there is not a lot on Central and Southern Africa. That would be because most of those tribal groups did not have written language so we do not have records of their history outside of oral traditions of the groups, or records of them made by other groups. Also you talk as though slavery was something unique to Imperial Europe and the Americas. It was not. Slavery has existed as long as civilization has existed and virtually every ethnic group on the planet has owned slaves and been slaves at some point in their history. | [
"The chronology of African recorded history encompasses many movements of art, African nations and dialects, and its history has permeated through many mediums. History concerning the much of the pre-colonialist African continent is depicted through art or passed down through word of mouth. As European colonization... | [
"You don't hear about the history of Africa before colonialism"
] | [
"Oral traditions of these areas exist."
] | [
"false presupposition"
] | [
"You don't hear about the history of Africa before colonialism"
] | [
"false presupposition"
] | [
"Oral traditions of these areas exist."
] |
2018-03748 | Why didn't POE (power-over-ethernet) replace the electric sockets | I'm sure there are other technical reasons as well but basically: PoE operates at 48v DC while electrical outlets operate at 120 AC. So first of all you need a device capable of operating on that frequency. Many devices like electric motors require AC voltage to operate so you would need an inverter built into all those devices. EDIT: or 240v in Europe/Japan etc Secondly is amperage. You can only run so many amps through the tiny wires of CAT6 cable. EDIT: PoE is 48v DC and a max of 13 watts, which is .25 amps. By comparison a traditional 60 watt light bulb (at 120v) requires .5 amps. While it's true that modern CFLs and LEDs need less juice to run, it shows how little power PoE is able to provide. You couldn't even make your coffee on .25 amps. CAT6 is considered low-voltage cable and has very different rules related to its installation for a reason. You couldn't power say a stove, or a fridge, or a blender on CAT6. That much amperage through CAT6 would cause it to melt and probably catch fire. You also need power to power the switch itself, which is considerably more power that PoE can provide. | [
"Ethernet networking of this period (mid 1980s to mid 1990s) used \"thin coax\" or 10BASE2. All devices on a network segment connected to the same electrical section of RG-58 coaxial cable. Intermediate devices were connected via a T piece. The two ends of the segment were terminated with a resistive network termin... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-07817 | What is it that makes one person allergic to Yellow Jackets but not Red Wasp stings or vice versa? | You are not allergic to the sting, you are having an allergic reaction to the antigenes injected into your body with the venom. Every wasp species produces slightly different toxins and therefore antigenes on these toxins that your body can have an allergic reaction to. | [
"The severity of the symptoms produced by \"WAS\" mutations correlate with their effects on WASp. Alleles that produce no or truncated protein have more severe effects than missense mutations. Although autoimmune disease and malignancy may occur with both types of mutations, patients with truncated \"WASp\" carry a... | [
"People are allergic to the stings of wasps",
"Allergic reactions of insect stings differentiate between each person."
] | [
"People are allergic to the antigens present in wasp venom, and those antigens vary in each species of wasp.",
"The allergy does not derive from the sting, but more so toxins that vary from the sting of the species of insect."
] | [
"false presupposition"
] | [
"People are allergic to the stings of wasps",
"Allergic reactions of insect stings differentiate between each person."
] | [
"false presupposition",
"false presupposition"
] | [
"People are allergic to the antigens present in wasp venom, and those antigens vary in each species of wasp.",
"The allergy does not derive from the sting, but more so toxins that vary from the sting of the species of insect."
] |
2018-02998 | Why are there alcohol IV bags in hospitals? | When someone gets methanol poisoning, they're actually being poisoned by the breakdown products of methanol rather than the methanol itself. Both ethanol and methanol are broken down by the same enzyme (alcohol dehydrogenase), and that enzyme preferentially acts on ethanol rather than methanol. Thus, one of the treatments for methanol poisoning is providing ethanol, which makes it so that the body stops breaking down the methanol and has a chance to eliminate the methanol and the toxic byproducts before they cause too much damage. | [
"Section::::Epidemiology.\n\nHemodialysis was one of the most common procedures performed in U.S. hospitals in 2011, occurring in 909,000 stays (a rate of 29 stays per 10,000 population). This was an increase of 68 percent from 1997, when there were 473,000 stays. It was the fifth most common procedure for patients... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04562 | what’s the difference between people that loose their voice and someone who’s mute? | Generally a person who has "lost their voice" is someone who overused their vocal chords and just strained them; they can still talk with effort and will regain their voice if given a bit of time to rest. A person who is mute, on the other hand, has suffered permanent damage or has other issues (genetic, etc.) that have caused them to permanently lose their ability to talk. If given time to recover they will *not* naturally heal and will remain mute. Side note: the word "mute" is sometimes used to just mean "silent" ("He remained mute"), but this usage is different from using it as a description of a person ("He is mute") which has the meaning listed above. | [
"Mute\n\nMute may refer to:\n\nBULLET::::- Muteness, a speech disorder in which a person lacks the ability to speak\n\nBULLET::::- Mute, a silent letter in phonology\n\nBULLET::::- \"Mute\" (2005 film), a short film by Melissa Joan Hart\n\nBULLET::::- \"Mute\" (2018 film), a science-fiction thriller directed by Dun... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-16532 | How does autorotation keep a helicopter from crashing in the event of a total engine failure? | There are two effects. One is simple, the other more complex. The simple effect is basically a parachute with more moving pieces. It's similar to a maple seed. As the helicopter falls the air makes the blades spin. It takes energy to make the blades spin, which comes from the helicopter falling. For the more complex effect we look at how a helicopter rotor works. When a helicopter wants to go up it doesn't just increase the speed of the rotor; that would be way too slow. Instead it has the ability to change the pitch of the blades. If you've held a flat hand out the window of a moving car then this should be familiar. Angle your hand up and it makes your hand try to rise. Angle it up more and it tries to rise more. Of course, the more you angle your hand up the more it gets pushed back, too. The blades if the helicopter are doing something similar, just in a circle. When the helicopter wants to land softly it can increase the pitch on the blades. They keep moving in the same direction due to their inertia, but now they're angled up and produce more lift. The helicopter can't do this for long without engine power because this upward angling makes the rotor slow down. Timed correctly it can cushion a hard landing | [
"At the instant of engine failure, the main rotor blades are producing lift and thrust from their angle of attack and velocity. By immediately lowering collective pitch, which must be done in case of an engine failure, the pilot reduces lift and drag and the helicopter begins an immediate descent, producing an upwa... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-02572 | Why does the mass of a particle change as it gets closer to the speed of light? | > Why does the mass of a particle change as it gets closer to the speed of light? It isn't *really* mass per se, it is *relativistic* mass which is a confusing concept which is usually no longer taught because it is more confusing than it is worth. Basically it refers to the total energy of the body and impacts the measurable inertia and gravitational attraction in a given reference frame. | [
"BULLET::::1. Relativistic mass: the mass of a particle is equal to the total energy of the particle divided by the speed of light squared. Since the total energy of a particle in relation to one system of reference differs from the total energy in relation to other systems of reference, while the speed of light re... | [
"Mass changes as particles get closer to light speed.",
"The mass of a particle changes as it gets closer to the speed of light."
] | [
"Mass doesn't change, the relativistic mass changes.",
"The mass of the particle isn't really changed, the total energy of the body is. "
] | [
"false presupposition"
] | [
"Mass changes as particles get closer to light speed.",
"The mass of a particle changes as it gets closer to the speed of light."
] | [
"false presupposition",
"false presupposition"
] | [
"Mass doesn't change, the relativistic mass changes.",
"The mass of the particle isn't really changed, the total energy of the body is. "
] |
2018-00501 | After you exercise (or do labor), why do you only feel sore the day after? | It is called DOMS, delayed onset muscle soreness. Basically, when you do hard exercises, your muscle cells are mines kinda damaged. This means that it releases a bunch of things, like ions, into the surrounding tissues. It is the accumulation is these stuff that give the muscle soreness. It is not lactic acid though. There's one experiment where people who are injected with lactic acid don't experience muscle soreness, and don't have decrease in performance. After a while, the muscle cells reabsorb the these stuff and the pain disappear | [
"Although there is variance among exercises and individuals, the soreness usually increases in intensity in the first 24 hours after exercise. It peaks from 24 to 72 hours, then subsides and disappears up to seven days after exercise.\n\nSection::::Cause.\n\nThe muscle soreness is caused by eccentric exercise, that... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-04412 | Why can't astronauts use sunlight in space to help grow vegetables/plants? | If their only mission was to grow plants, they'd be able to do so. Since they've got other concerns, it's much easier to recreate the light source than it is to constantly maneuver the ship so to have direct sunlight for 14 hours a day. You'd also need a clear bulkhead to allow the light in. It's just easier to balance all of the needs on the ISS with artificial light. | [
"A variety of technical challenges will face colonists who attempt to do off-Earth agriculture. These include the effect of reduced gravity, lighting, and pressure as well as increased radiation. Though greenhouses may solve many of the problems presented in space, their construction would come with their own set o... | [
"Astronauts can't use sunlight to grow plants in space."
] | [
"They could if that was their main mission but it is not the mission. "
] | [
"false presupposition"
] | [
"Astronauts can't use sunlight to grow plants in space."
] | [
"false presupposition"
] | [
"They could if that was their main mission but it is not the mission. "
] |
2018-00429 | Why does ecstasy/MDMA make you feel loving and dig deep into emotions? | it floods your brain with seratonin, one of the main hormones associated with happiness and love (the other main one is dopamine). Now we understand the brain pretty well when it comes to the electro chemical aspects, but the other aspects are not well understood at all, so I don't know if there is any solid answer on why MDMA helps people who have experienced trauma, and I'm guessing if there is an answer it's probably very contraversial. But we understand some problems we have in regards to mental illness are due to some kind of imbalance in our brain chemistry, so flooding our brain with seratonin kind of flips the imbalance the other way for a period. Also sometimes we lock away trauma in our brain due to the intense distress it has caused us, but when our brain is flooded with seratonin we block the emotions and hormones associated with trauma. This isn't much of an answer because mental illness and MDMA and brain chemistry are all things that neurologists will admit they only have a limited understanding of, let alone me. I guess the real answer is that we have some understanding of what MDMA and seratonin is, but mental illness, trauma, memory, ect are still very hard to grasp for us. So if it helps, the reason why is a bit of a mystery. | [
"MDMA (ecstasy) is a drug that also alters one's state of consciousness. The state of consciousness brought about by MDMA ingestion includes a rise in positive feelings and a reduction in negative feelings (Aldridge, D., & Fachner, J. ö. 2005). Users' emotions are increased and inhibitions lowered, often accompanie... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04245 | why do get an electric shock as a human if you touch an object or another person? Like giving someone a hand for instance | Static electricity can build up on many things including you. When you give that electric charge the chance to ground itself is when you get that shock. | [
"Section::::Pathophysiology.\n\nThe minimum current a human can feel depends on the current type (AC or DC) as well as frequency for AC. A person can feel at least 1 mA (rms) of AC at 60 Hz, while at least 5 mA for DC. At around 10 mA, AC current passing through the arm of a human can cause powerful muscle contract... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-06887 | What's the difference between copyright and trademark symbols? | The difference is the type of asset they protect. Copyright protects works, such as books, movies, or games. Trademark protects the company brand, such as name, logo, or slogan. | [
"BULLET::::- The oldest U.S. registered trademark still in use is trademark reg. no 11210, a depiction of the Biblical figure Samson wrestling a lion, registered in the United States on May 27, 1884 by the J.P. Tolman Company (now Samson Rope Technologies, Inc.), a rope-making company.\n",
"Use of the trademark s... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-09451 | How do honeycombs and beeswax form nearly perfect hexagons? | The hexagon is a very spatially efficient shape which uses less material. Try this experiment: wash your hands with soap, and spread the lather out on a flat surface. The bubbles will spontaneously acquire hexagon-like shapes and arrange themselves neatly. You see the same patterns in basalt columns and mudcracks because it fills the space using little energy. | [
"Individual cells do not show this geometric perfection: in a regular comb, deviations of a few percent from the \"perfect\" hexagonal shape occur. In transition zones between the larger cells of drone comb and the smaller cells of worker comb, or when the bees encounter obstacles, the shapes are often distorted. C... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-15701 | if we can say that, in the 3 physical dimensions, we are always in the center of the universe, no matter where we are, the is the present time the "center" of the 4th dimension, time? | As time passes, we are always moving along the time axis. If we assume there is no beginning or end to time, that time is infinite in both directions, then you would be correct. If there is either of those, then there would be no 'center'. | [
"Professor Brian Cox explores our origins, place and destiny in the universe. He describes the initial conditions of the human psyche as one that places itself at the center of the universe, surrounded by family, environment, and events. Brian tells the story of how our innate human curiosity has led us from feelin... | [
"Everything is always in the center of the universe."
] | [
"There is a possibility that there could be no center of the universe."
] | [
"false presupposition"
] | [
"Everything is always in the center of the universe."
] | [
"false presupposition"
] | [
"There is a possibility that there could be no center of the universe."
] |
2018-04105 | why does the USA need to import 90 percent of the aluminum it consumes when there is so much aluminum recycling going on? | A lot of scrap aluminum from the U.S. is actually recycled in other countries. So it's being recycled, but in the trade statistics you'll see exports of aluminum scrap as well as imports of aluminum. | [
"The recycling of aluminium generally produces significant cost savings over the production of new aluminium, even when the cost of collection, separation and recycling are taken into account. Over the long term, even larger national savings are made when the reduction in the capital costs associated with landfills... | [
"We don't need to import aluminum because we have so much recycled.",
"Aluminum is recycled in the USA."
] | [
"The recycled aluminum is exported to other countries. ",
"Aluminum is exported and recycled outside the USA. "
] | [
"false presupposition"
] | [
"We don't need to import aluminum because we have so much recycled.",
"Aluminum is recycled in the USA."
] | [
"false presupposition",
"false presupposition"
] | [
"The recycled aluminum is exported to other countries. ",
"Aluminum is exported and recycled outside the USA. "
] |
2018-11171 | Is it actually possible for a sound wave to travel around the entire world and be heard? | Yes, the explosion sound of the volcano Krakatoa went around the world *more than once.* URL_0 | [
"Theories on the generation of these sounds may partially explain them. For example, scientists at NASA suggested that the turbulent ionized wake of a meteor interacts with Earth's magnetic field, generating pulses of radio waves. As the trail dissipates, megawatts of electromagnetic power could be released, with a... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-06922 | If space is considered international waters, why does Space X need permission from the FCC to use their own product in space? | Space is not "international waters", space is considered space. But even so ships that are in international waters need to be registered under some country so you cannot launch a ship and operate it in international waters without the local government coming after you for not registering properly. Finally the FCC regulates the radio spectrum so even with satellites in space their communications are passing through the jurisdiction of the FCC. They are talking to someone on the ground using radio so obviously they need to follow FCC rules. | [
"Both UN General Assembly Resolution 1962 (XVIII) and the Outer Space Treaty (OST) of 1967 have established all of outer space as an international commons by describing it as the \"province of all mankind\" and, as a fundamental principle of space law, declaring that space, including Moon and other astronomical obj... | [
"Space is considered \"International waters\".",
"Space is considered international waters."
] | [
"Space is not considered \"International waters\" space is considered space.",
"Space is not considered to be international waters, it is simply considered to be space. "
] | [
"false presupposition"
] | [
"Space is considered \"International waters\".",
"Space is considered international waters."
] | [
"false presupposition",
"false presupposition"
] | [
"Space is not considered \"International waters\" space is considered space.",
"Space is not considered to be international waters, it is simply considered to be space. "
] |
2018-00326 | Why are people dying from the flu? | I assume you're asking about why this year's flu season is particularly bad, not why flu can kill you. This year's strain is primarily H3N2. This is bad for two reasons. First, H3N2 flu just tends to be nastier than other strains. Not all flus are created equally, and this year we just drew a crappy hand in that regard. In addition to H3N2 being particularly nasty, it is also often difficult to vaccinate against for two reasons. The H3 and N2 bits of the name refer to certain surface proteins on the virus. The way we make a lot of the flu vaccines we do is by basically growing lots of viruses in chicken eggs. Chickens and humans aren't the same, and as a result, there will often be slight differences in the virus we'd like to vaccinate against, and the one we've managed to mass produce. Often this isn't a big deal, but with H3N2 strains, it tends to be a bigger deal. Second, this strain mutates quicker than many other flu strains. There can actually be rather large differences in what this virus looks like genetically from the beginning of the season to the end. This can render vaccines less effective. [EDIT: Also, not enough people get the flu shot. Seriously, just go get the shot. I'm glad you've never gotten the flu shot or the flu, but individual cases of the flu being lessened isn't the real benefit of the vaccine. In addition to it helping you if you're exposed to the virus, high vaccination rates lead to less exposure to the virus in the first place for everyone in the population (including those that are deathly allergic to the shot, for example).] So, in short, this year's flu strain is just a nasty one, and it is difficult to vaccinate against | [
"Medical conditions that compromise the immune system increase the risks from flu.\n\nSection::::Health conditions likely to cause complications.:Diabetes.\n\nMillions of people have diabetes. When blood sugars are not well controlled, diabetics can quickly develop a wide range of complications. Diabetes results in... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-06585 | How do credit settlement companies who claim that people who have a lot of debt don't have to pay it back work? | Broke people can't pay their bills. It's just math. So let's say you owe your credit card companies $25,623 and you don't really have any way of paying that back. You might file bankruptcy, and the credit card companies would get little or nothing. OR they could agree to take $5,000 and just give up on the rest. This is probably a better option than forcing you into bankruptcy, because $5,000 > $0. So these companies work with your credit card companies and other creditors to arrange a settlement. It usually looks like them paying $5,000 to the credit card company to wipe out the debt, and then you end up paying them $6,000 over time, so they make money too. | [
"Section::::Professional debt settlement.:Advantages.\n\nSettlement companies generally package their settlements into a larger bulk settlement with the creditor for 35% - 50% of the existing balances. The debt settlement companies typically have built up a relationship during their normal business practices with t... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-22874 | How does a circuit deal with having relatively large generation during times of low demand, such as might be in a parked electric diesel engine? Does this change for a more constant generator type such as hydroelectric? | In your example, the power on the diesel engine would just be turned down (or the engine would be turned off). The resistance of a generator is proportional to the power being drawn from it. So in a hydroelectric dam, if the power requirements are low, more water is diverted around the turbines, or they'd start speeding up. | [
"A hydroelectric plant's production may also be affected by requirements to keep the water level from getting too high or low and to provide water for fish downstream. \n\nHowever, solar, wind and hydroelectric plants do have high availability factors, so when they have fuel available, they are almost always able t... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-23417 | Why do certain shower curtains always seem to consistently push into or touch you as you shower? | The movement of the water causes a low pressure area which pulls air from the other side of the curtain, making the curtain float towards you | [
"Section::::Structure and design.:Shower and bathtub curtains.\n\nCurtains can be used in shower or bathtub enclosures with two main purposes: to provide privacy and to prevent water from flooding or spraying outside the shower or bathtub area. Shower and bathtub curtains usually surround the bath inside the tub or... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-12326 | What happens to an asteroids material when it burns up in the atmosphere? | First off, because a lot of people don't realize it, I want to point out that typically this *is not* much material. The majority of shooting stars one sees are probably about the size of a grain of sand. As far as what happens to the material, it turns into gasses or melted particles. Beyond that, all they are is dust on the wind. | [
"For volatile materials in extinct comets, heat can be used to melt and vaporize the matrix.\n\nSection::::Extraction techniques.:Extraction using the Mond process.\n",
"One proposed method of purifying asteroid materials is through the use of carbon monoxide (CO). Heating the material to 500 °F (260 °C) and expo... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-04919 | How did English become the most commonly spoken language in the world when the population density of other races far exceeded those of European/Caucasian descent? | The British Empire. It doesn't matter how many people live in the countries where they originated now. It matters how many people were forced or incentivised to learn the language some centuries ago, and the British Empire covered nearly a quarter of the world's population at its greatest extent. | [
"English-speaking world\n\nOver 2 billion people speak English, making English the largest language by number of speakers, and the third largest language by number of native speakers. With 300 million native speakers, the United States of America is the largest English speaking country. As pictured in the pie graph... | [
"The most commonly spoken language is the one from the country with the highest population density."
] | [
"People were forced or incentivised to learn English in the British Empire."
] | [
"false presupposition"
] | [
"The most commonly spoken language is the one from the country with the highest population density."
] | [
"false presupposition"
] | [
"People were forced or incentivised to learn English in the British Empire."
] |
2018-09554 | Why do movie, TV, and video ratings differ? Why aren't they all just the same depending on the content? | The ratings system in the US was put in by private business, and the agreement was that they'd put ratings out so that the government wouldn't censor films. This continued on to TV and video games. So each of the ratings systems are separate private entities owned by different people. MPAA for films, NAB + MPAA for TV, and the ESRB (owned by ESA) for video games | [
"The ratings are generally applied to most television series, television films and edited broadcast or basic cable versions of theatrically released films; premium channels also assign ratings from the TV parental guidelines on broadcasts of some films that have been released theatrically or on home video, either i... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-02928 | Why does everyone in Reddit use Imgur so much to post images? | Before Reddit had its own image upload feature, a user created Imgur specifically for redditors to use. [Here's an AMA with the creator]( URL_0 ) [Here's the thread where it was introduced]( URL_1 ) | [
"Section::::Sharing methods.:Link aggregation sites.\n\nImage sharing on social news and image aggregation sites such as Reddit, Imgur, 4chan, Pinterest and Tumblr allow users to share images with a large community of users. Images are the most liked content of the aggregation and media sharing site Reddit; and acc... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-02054 | Why are the words "Yeah" and "Oh" always in pop songs and said for so long? | They are used as *filler* where the tune requires a note, but the singer doesn't have anything more to say. An excellent lyricist will try to adjust the wording so that not too many of these are needed. | [
"There are several different types of formulaic language. One type is relatively universal, often transcending differences in language and to some degree culture. Simple fillers like \"Uhm\", \"Uh\", or \"Er\" are used by many different people in many different settings. For the most part, these types of fillers ar... | [] | [] | [
"normal"
] | [] | [
"normal",
"normal"
] | [] |
2018-01258 | What makes gasoline so special that it can power engines and why is it so difficult to find an alternative fuel source? | it's flammable, high energy output, easy to transport, and stays liquid in decently wide variety of temperatures. lots of things can power an internal combustion engine. diesel, peanut oil, alcohol to name a few. | [
"Petroleum-based vehicle fuels can be replaced by either alternative fuels, or other methods of propulsion such as electric or nuclear.\n\nAlternative fuel vehicles refers to both:\n\nBULLET::::- Vehicles that use alternative fuels used in standard or modified internal combustion engines such as natural gas vehicle... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
2018-01165 | Why do lines appear in the picture when you photograph a computer screen? | [Relevent XKCD.]( URL_0 ) Your computer's made of a bunch of little squares that all work together to show you a single image, called pixels. These pixels are arranged in a grid of rows and columns to display images on our screens. Now, your phone or camera also has a pixel grid, but unless you have a really specific device, chances are it's gonna have a different size pixel grid than your computer. Since these grids are different sizes, they don't play nice with each other, and that's why the computer grid is visible in photos, because the camera's grid won't sit neatly on top of the computer grid, "hiding" it from view. | [
"Photographs of a TV screen taken with a digital camera often exhibit moiré patterns. Since both the TV screen and the digital camera use a scanning technique to produce or to capture pictures with horizontal scan lines, the conflicting sets of lines cause the moiré patterns. To avoid the effect, the digital camera... | [] | [] | [
"normal"
] | [] | [
"normal"
] | [] |
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