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what is a centromere? | During mitosis, a cell splits its genetic material in half, with each daughter cell getting an equal number of chromosomes. Before the chromosomes are split up, the DNA has to be copied so that way there are 2 copies of each chromosome to be split up later. After DNA replication up to the anaphase period of mitosis, each chromosome is attached to the copy of itself. The location of this attachment is called the [centromere](_URL_0_).
The importance of the centromere is that it can be sometimes be seen on microscope images of a nucleus and that it is where the kinetochore forms. The kinetochore is a structure important for separating the sister chromatids (the chromosome and its copy). [Spindle fibers](_URL_1_) attach to both sides of the chromosomes at the kinetochores. The spindle fiber-kinetochore interaction causes the chromatids to be pulled apart, causing them to go to different daughter cells. | [
"The centromere is the specialized DNA sequence of a chromosome that links a pair of sister chromatids (a dyad). During mitosis, spindle fibers attach to the centromere via the kinetochore. Centromeres were first thought to be genetic loci that direct the behavior of chromosomes.\n",
"It may also be analytically ... |
why do powerful drag racing engines sound so terrible when they're in idle? | When you have a fixed cam profile, as is the case for the majority of racing engines, you can either have a smooth idle or good power at the top RPMs. Race engines spend most of their time turning fast and don't need a smooth idle.
Lots of road-going vehicles made now have the ability to switch cam profiles in one way or another, but this adds weight and complexity to an engine that is unnecessary and wasteful in a racing engine. | [
"BULLET::::- Cackle Fest: A.) (Drag Racing) Referring to when 2 Top Fuel or Funny Car cars are sitting at the starting line and one or both cars refuse to stage. The motor noise at idle sounds like a cackle. At the discretion of the starter, they can order the drivers to stage or even have them pull out of the lane... |
why does light oscillate? | The photon travels in straight lines and isn't wiggling around like you see in some animations. That's just a bad way of showing the wave nature of it.
For imagination purposes don't think of waves in the ocean that have motion up and down as they travel across the surface. Think of light more like sound waves. Sound waves are oscillations just like ocean waves, but nothing is moving across the direction of travel because the sound wave is just a pressure front. It's not a perfect analogy since sound travels in something, but light does not. The light is just the electric and magnetic fields alternately collapsing and inducing the creation of the other field which then collapses and induces...etc. | [
"Since light is an oscillation it is not affected by traveling through static electric or magnetic fields in a linear medium such as a vacuum. However, in nonlinear media, such as some crystals, interactions can occur between light and static electric and magnetic fields — these interactions include the Faraday eff... |
url shorteners and why can't webs just use it "natively"? | This is a commonly posted topic here. Please see [these previous posts.](_URL_0_) If they don't entirely answer your question, you might create a new post with
a more specific question.
Try our handy Search function sometime. :-)
For best results in most cases, use 2 or 3 general, common words
that refer to the key concepts in your topic. | [
"Web applications often include lengthy descriptive attributes in their URLs which represent data hierarchies, command structures, transaction paths and session information. This practice results in a URL that is aesthetically unpleasant and difficult to remember, and which may not fit within the size limitations o... |
Why is Israel hiding its nuclear project? | The US in the 1960s tried to strongly discourage Israel from getting nuclear weapons, because it feared that it would lower US freedom of action in the Middle East and increase the possibility of a Middle Eastern arms race. Israel did it anyway, going to great lengths to deceive US inspectors.
By the 1970s, it was clear to the Americans that the Israelis had nuclear weapons and weren't going to give them up. But they still didn't want other nations in the Middle East to pursue their own nuclear weapons, and had passed laws that basically said that the US won't cooperate militarily with nations that are in violation of the Nuclear Non-Proliferation Treaty. So this put the US and Israel in a bind. Israel didn't want to give up its nukes, and the US didn't want to abandon Israel as a military ally in the region.
The compromise was an agreement, negotiated by the Nixon administration, in which it was agreed that Israel would not "introduce" nuclear weapons into the Middle East. What does "introduce" mean? The US and Israelis hammered out a fig-leaf of an agreement: if you haven't tested a nuclear bomb, and you don't acknowledge you have a nuclear bomb, and you don't threaten anyone with a nuclear bomb — do you really have a nuclear bomb? Have you really "introduced" them into a region? Or are they all just hypothetical, on paper?
This is obviously quite inadequate, but it worked for diplomatic reasons. As a result, Israel cannot acknowledge its nuclear arsenal without running afoul of US laws, and exposing the US to charges of hypocrisy and willing subversion of the NPT regime. On the other hand, everyone knows Israel has nuclear weapons — they haven't been perfect about covering it up at all. So this policy of "nuclear opacity," in which Israel does not confirm or deny its nuclear arsenal, but everyone knows it has them, does two things: it satisfies a diplomatic relationship with the US, while also giving Israel the deterrent power of the weapons (since everyone knows they have them).
The fact that Israel has been known to be in flagrant violation since the mid-1980s (the Vanunu releases) has arguably weakened the power of this arrangement, as has their possible involvement in a test, and indeed there are many who claim that Israel should just admit to what everyone knows, and of course other nations in the Middle East (Iran, Saudi Arabia, perhaps more) are interested in nuclear weapons in part as a counter. So whether this policy has been _successful_ is a different question.
Avner Cohen's book, _The Worst-Kept Secret_, is a great place to read more about these policies. | [
"It also recommended that Israel should retain its current policy of deliberate ambiguity regarding its nuclear status. If, at a later date, other states in the Middle East (particularly Iran) were to acquire nuclear technology that Israel perceived as a threat, then the Daniel Project recommended limited disclosur... |
why do we put gnomes in our gardens? | Because they look nice. Seriously, that's just about it. Putting statues in your garden started during the Renaissance and was dwarves and the like and has stuck around since. The standard lawn gnome comes from 1800s Germany.
Source: _URL_0_ | [
"Garden gnomes () are lawn ornament figurines of small humanoid creatures known as gnomes. Traditionally, the figurines depict male dwarfs wearing red pointy hats. Typically, gnomes stand between . A recent trend has introduced miniature gnomes of only a few inches in height. Originating as a decoration for wealthy... |
Why did the French wear blue uniforms during WW1? Did this not leave them poorly camouflaged? | It was a longstanding tradition. Other countries had recently adopted camouflage uniforms, and in 1912, French Minister of War Adolphe Messimy saw their advantages and tried to change the French uniform. However, there was mass protest. The colorful uniforms, it was felt, were linked to Army prestige - which embodied national honor that had been besmirched by the loss of Alsace-Lorreine in the Franco-Prussian war and would someday be regained by military victory.
To banish "all that is colorful, all that gives the soldier his vivid aspect", wrote the Echo de Paris, a prominent newspaper, "is to go contrary both to French taste and military function." Finally, a former war minster cried in Parliamentary hearings, "Eliminate the red trousers? Never! Le pantalon rouge c'est la France! *[The red pants are France!]*"
The proposed change failed; French soldiers marched off to war with a "vivid aspect" that no longer performed any "military function."
(Source: Most prominently, Barbara Tuchmann, *The Proud Tower* and *The Guns of August*. William Shirer's *The Collapse of the Third Republic* also discusses this point.) | [
"The basic German (Luftwaffe) camouflage during most of the war was based on a light blue undersurface and a two tone splinter pattern of various greens for the upper surfaces. In the first year of the war, the top colors were dark green and black-green; later, lighter and more greyish colors were used for fighters... |
why is there such a high education requirement for menial jobs? | A big part of this is the labor market in general. When there is high demand for labor and low supply (low unemployment), companies can't be very picky about who they hire, especially for menial jobs.
Right now more people are looking for jobs, so companies can be more particular about who they hire. Even in a menial job, companies always want to hire the best person they can, so they raise their standards. | [
"Due to the rarity of men in early childhood education, men who do choose to enter the profession can find it easy to obtain employment, and may have more employment options, because of the preference for hiring men. In essence, men tend to have slightly more leverage or pull compared to women with similar qualific... |
Did Hitler actually take away guns from the Jews? | From an [earlier answer on this topic](_URL_0_)
it was actually Weimar Germany that instituted wide-scale legislation restricting firearms in 1922 with the *Republikschutzgesetz* (law for the protection of the Republic). Under the rubric of "endangering public safety," the *Republikschutzgesetz* outlawed the organizations from owning unauthorized weapons, the creation and brandishing of a weapons arsenal, and criminalized the failure to report on the existence of weapons arsenal. But gun control and regulation was not the primary focus of the *Republikschutzgesetz* but rather to restrict the operations of various anti-republican groups and provide grounds for their prosecution. The *Republikschutzgesetz*'s provisions on firearms were predicated upon a pre-existing January 1919 Reichstag legislation which banned the private ownership of firearms to meet provisions of the Versailles Treaty which called for a wide-ranging German disarmament, including non-state affiliated militias.
The 1928 Law on Firearms and Ammunition liberalized restrictions on guns and their ownership, but still provided a strict regimen of regulation and permits. Applicants for gun ownership had to demonstrate both necessity and reliability. In the latter case, members of itinerant groups such as gypsies or criminals were forbidden from gun ownership. The 1928 law also waived the need for a permit by state officials since they had already demonstrated the requisite amount of political loyalty and responsibility.
The Third Reich's 1938 *Reichswaffengesetz* had much of the same language as its Weimar predecessor, but it paradoxically was a simultaneous liberalization and restriction of existing gun laws. The *Reichswaffengesetz* ended a number of restrictions in the 1928 law for rifles and shotguns and largely focused on restricting private handgun ownership. It also eliminated the need for transfer permits for rifles and shotguns and held that a legal hunting license sufficed as a permit for holding firearms. members of the NSDAP were also a privileged group and thus could more easily obtain the requisite permits.
Where the *Reichswaffengesetz* and its Weimar equivalent parted ways was the former's restrictions on gun ownership by individuals deemed subversive to the state. To an extent, this was a change in degree as the Third Reich was much more explicit about who was a state enemy while the Weimar law was more circumspect. The *Reichswaffengesetz* provided a later justification in November 1938 for the Interior Ministry to prohibit Jews from owning any type of dangerous weapon. The *Reichswaffengesetz* was of a piece with other legislation of the Third Reich: it set up Aryan Germans as a privileged elite, especially those who served the state and the party, while restricting the civil rights of those excluded from this racial compact.
As for Ben Carson's recent comments and the wider sentiments about gun legislation in Germany as exemplified by all too typical facebook posts and [this bumper sticker](_URL_2_), they have a number of faults that makes their historical analysis very problematic. First off, these type of arguments tend to come up quite short when it comes to both explaining the context and the nature of these laws. For example, the Weimar government passed these laws on gun ownership in no small measure because there were a large number of paramilitary *Freikorps* groups operating in Germany who explicitly stated their goal was to overthrow the Republic. Sometimes these stated goals turned into action as with the Kapp *Putsch* or the NDDAP's Beer Hall *Putsch*. Furthermore, examining the *Reichswaffengesetz* in isolation from other German legislation loses a good deal of the picture; arguments as exemplified by Carson's assume that gun legislation *preceded* wider erosion of civil liberties when that clearly was not the case here. The [Nuremberg Laws](_URL_1_), which provided a whole panoply of civil rights restrictions, preceded the *Reichswaffengesetz* by a good three years. From a historian's standpoint, it is more valuable and fruitful to look on laws on gun ownership as part of a larger process of social exclusions and restrictions directed at Jews rather than a vital precondition for them.
Finally, another big problem with this type of analysis is it blithely assumes that American gun culture and patterns of ownership are a universal given. Not only does this portray American gun culture as a monolithic (which it clearly is not- Americans own guns for many different reasons beyond hunting and self-defense), but relies upon the unspoken assumption that different cultures and societies view guns the same way and possessing the same function. This is a highly erroneous way to view the issue as patterns and attitudes to gun ownership are often contingent on a myriad number of factors ranging from recent history, legal traditions, social norms, or economic development. While there might be some overlap with US gun culture, there are also differences as there would be with any material item (cars, computers, home ownership, etc.). To homogenize history in this way is lazy and unreflective at best, and needlessly politicizes an important topic of analysis.
*Sources*
Evans, Richard J. *The Coming of the Third Reich*. New York: Penguin, 2005.
Harcourt, Bernard E. "On Gun Registration, the NRA, Adolf Hitler, and Nazi Gun Laws: Exploding the Gun Culture Wars (A Call to Historians)." *Fordham Law Review* 73 (2004): 653-80. | [
"The Disarmament of the German Jews started in 1933, initially limited to local areas. A major target was Berlin, where large-scale raids in search for weaponry took place. Starting in 1936, the Gestapo prohibited German police officers from giving firearms licenses to Jews. In November 1938, the \"Verordnung gegen... |
Who were the Denisova hominin? | History is only the story of humans that have left records; it isn't the study of things that have happened in the past unless they were recorded (hence this is PREhistory). You are thinking of anthropology. Try /r/anthropology for details.
Edit: Here's my take: They're a recent find, so the stuff you can find on Wikipedia is pretty much all anyone can KNOW about them right now, since there were only two small bones found. Like Homo neanderthalensis, they are thought to be another hominid species that may have interbred with Mongoloid populations of early Homo sapiens in Asia just as Neanderthals may have interbred with Caucasoid populations of early Homo sapiens in Europe. Due to that, ecological displacement, and/or open warfare, these evolutionary cousins died out. Unlike Homo floriensis, which also existed contemporaneously with Homo sapiens, there is evidence that suggests they contributed some of the DNA that makes up Homo sapiens sapiens. | [
"The Denisovans or Denisova hominins ) are an extinct species or subspecies of archaic humans in the genus \"Homo\". Pending its taxonomic status, it currently carries temporary species or subspecies names \"Homo denisova\", \"Homo altaiensis\", \"Homo sapiens denisova\", or \"Homo sp. Altai\". In 2010, scientists ... |
Did the Native Americans of the Great Plains and the West communicate with tribes farther east about the presence of white settlers before they actually met them? | There are a couple complications to this questions. First, for the southern Plains at least, contact with Europeans began in 1540s when de Soto's expedition into present day American Southeast attempted to retreat back to Mexico through Texas and when Coronado's expedition marched from the American Southwest into Kansas. So Native American-European interaction in the Great Plains began very early--earlier, in fact, than many areas farther east. The Spanish coming up from the south would be the major European presence in the American West for a long time as well.
The second complication is that many of the Great Plains nations people are most familiar with are relatively recent inhabitants of the region. So people like the Lakota and the Cheyenne *were* the "tribes farther east" in the 1600s.
All that said, there was plenty of trade and contact going on in the Great Plains and elsewhere to carry news and European trade items. For the Plains, the Apache (later the Comanche who took over many of the Apache trade routes on the Plains) were the main source for Spanish goods, as they traded with the Spanish-controlled Pueblos, while the Utes and Navajo linked the Southwest with the Great Basin and provided a secondary route to the northern Plains. French goods mainly went through the Cree, Illinois, Osage, Caddo and other nations who lived near the Great Lakes or Mississippi. These trade routes would carry information as well as goods into the interior of the continent. | [
"With the help of the Native Americans, they were able to find the rest of their way north through the woods. Before long they encountered a vessel with men working to load corn into it. After being received by them, Henson spoke to the captain who received him warmly and agreed to take them to Buffalo, which is wh... |
My mom inherited a bunch of Roman Catholic artifacts. Here are a few of them. Anyone know more about them? | I can comment very generally on 2. 2 does indeed look like a pair of leaves cut from a 16th century manuscript or at any rate the style of of the leaves fits with other early 16th century manuscripts. They depict the evangelists Mark and Luke with their respective symbols(winged ox and bull). My guess is that they were cut from their original manuscript by the dealers who framed them; it used to be a fairly popular practice to do this although you lose a lot of contextual information this way. If you want to research these leaves further my suggestion would be to take them to a local museum, university, or auction house and see if they can help you track down the manuscript they were cut out of; it may be possible to do this if the dealer's catalogs include other leaves from the same manuscript.
The inscription on the back of 4 says I think "Angelico painting, copied by Rocchio" and then a street address in Florence; given that this is quite clearly in the style of the painter Fra Angelico my guess is that it is a modern copy of a Fra Angelico painting? | [
"The church also contains a purported relic of Saint Clemens that is in fact an example of a so-called catacomb saint, a corpse that has been taken from the Roman Catacombs, decorated, given a fictitious name, and presented as the relic of a Roman Catholic saint.\n",
"According to \"Roman Catholic Saints\", the r... |
what does it mean to testify before (us) congress? | The House of Representatives and the Senate have, like the Parliament of the United Kingdom, a "power of inquiry." To assist in their lawmaking power, they can call individuals to testify before the houses or their committees to investigate a matter. The people summoned before the committee are required to answer all questions truthfully, unless it violates their Fifth Amendment right not to incriminate themselves.
The idea is that Congress will use the information from these investigations to pass laws. For example, it might hear testimony from experts on a subject. When it investigates executive officials, it might help to decide whether those officials should be impeached, which is a power of the House. | [
"BULLET::::- George W. Bush – President; testimony not under oath. The session was not officially transcribed because the White House considered it a \"private meeting\" in which highly classified information would be discussed. Asked to limit the length of testimony to one hour (However, the meeting lasted for thr... |
if tv remotes emit infra-red rays, then why does camera lens pick violet rays being emitted from the remote? | First, a quick introduction to how camera sensors work:
Camera sensors actually just see in "black and white". That is, they only measure light intensity, not frequency. The sensor itself doesn't know if a photon hitting it has the "red" wavelength or the "blue" wavelength.
To figure out which wavelength a photon is of, a filter grid is placed on top of the sensor to allow the camera software to figure out what colors things are.
If the filter over sensor pixel number one only lets blue light through, the camera knows that if pixel #1 detects any light at all, it is of the blue variety. The filter on top of next pixel on the sensor only lets green light through, so if the same blue light hit that part of the sensor, it would be blocked by the filter and the sensor wouldn't show any light at that spot.
This process is repeated for all of the several million pixels the camera sensor has, and when the camera software combines the information about how the color filter is arranged with the light detected by the sensor, it can use this to calculate a color image even if the sensor is only able to see black and white.
So, let's say an infrared photon hits the camera sensor. If the color filter i mentioned earlier isn't made to block infrared wavelengths, all pixels on the sensor get lit up by it. Slight variations in each color filter's ability to block IR wavelenghts might cause the blue filter to block less of the IR than the other two colors, but still not all of it. As a result, it would show up as bright with a purple tint. If the red filter had been able to block 100% of IR radiation, but the other two filter did not block it at all, the IR would look cyan.
You can read up on bayer filters for more information. _URL_0_
tl;dr: All camera sensors are sensitive to a wide range of light and don't natively see in color. The weird color from non-visible light is caused by the color filter on top of them not blocking IR and UV perfectly, or at all. | [
"Image intensifiers have been introduced that increase the brightness of the screen, so that the patient needs to be exposed to a lower dose of X-rays. Whilst this reduces the risk of ionisation occurring, it does not remove it entirely.\n",
"The television receiver would use the output of the photoelectric cell ... |
Was there any existing plans on how the Axis countries would coexist in the event they won WW2? | Check this answer by /u/commiespaceinvader, it's quite in depth.
_URL_0_ | [
"With the signing of the Tripartite Pact on September 27, 1940, creating the Axis of Germany, Japan, and Italy, Decoux had new grounds for worry: the Germans could pressure the homeland to support their ally, Japan.\n",
"Planning for global territorial expansion of the Axis powers; Germany, Italy and Japan, progr... |
why is it necessary to shoe and maintain shoeing horses, but wild ones are fine? | Wild ones don't walk of roads or pull vehicles on roads. This exposes them to a different sort of wear profile, which they have evolved to handle naturally. Working horses are doing unnatural things, so they have to have tools to do their jobs well, just like people. | [
"Nonetheless, domestic horses do not always require shoes. When possible, a \"barefoot\" hoof, at least for part of every year, is a healthy option for most horses. However, horseshoes have their place and can help prevent excess or abnormal hoof wear and injury to the foot. Many horses go without shoes year-round,... |
*Why* did the Luftwaffe fail to beat the RAF? |
- RAF operated over it's own territory, it's fighters could stay in the air longer, it's pilots were not permanently lost after bailing-out, and aircraft forced to crash-land could be recovered. Also, bomber losses are much harder to replace in terms of manpower and treasure - fighters are relatively cheap.
- German intel greatly under-estimated the resilience of Fighter Command, British industrial capacity, and civilian morale - particularly in relation to the effectiveness of their bombing campaign. This lead to questionable operational decisions and tactics.
- Attrition, Fighter Command maintained and even expanded operational effectiveness - unlike the Luftwaffe, most of their fighter pilots were very inexperienced at the start - even with their high losses pilot skill and training only improved overall, where the Luftwaffe struggled to replace losses of experienced aircrew and saw a degradation of effectiveness. And the British had friends, 20% of their pilots in the BoB were foreigners (approx 600 of 3000).
- The Luftwaffe lacked in heavy bomber/long-range fighter designs, the aircraft they used were simply not designed for a strategic aerial war, and more for tactical/operational tasks in conjunction with the army/navy. Their bombers had modest payloads and were virtually defenseless without fighter support - and their fighters didn't have the range to cover all of England.
- Fortunes of war. | [
"The \"Luftwaffe\"'s poor intelligence meant that their aircraft were not always able to locate their targets, and thus attacks on factories and airfields failed to achieve the desired results. British fighter aircraft production continued at a rate surpassing Germany's by 2 to 1. The British produced 10,000 aircra... |
how can social security be in trouble when people pay through a social security tax to fund it. | Well, its a little more weird and complex than that.
First, you are paying in but the people who currently need it are drawing on your funding of it. As will you from the people who pay after you.
Second, the politicians love to tweak things and they made a few major tweaks. Here is one: the capped the contribution. I believe its capped at $150,000 a year but it doesn't matter really - here is the point:
If you make above the cap you only pay into social security based on the cap. So, if you make 1 million a year you pay the same as someone who makes only $150,000 a year.
This is an example of how people with an agenda of privatizing S.Sec. underfund it so they can argue that it is going to fail so we have to privatize it. Self-fullfilling prophecy anyone?
**It's not really in trouble.**
This is classic thunder without lighting - if you repeat the noise enough people will believe there is a storm coming even if there isn't.
It will be in trouble eventually if we don't do something about how the politicians already screwed it.
**Oh yeah.**
Then there is the bit about how Ronald Reagan (R) and Tip O'Neil (D) made a deal that said they could borrow money from it. See, its also in trouble because the politicians decided that the government could borrow our savings from us (savings that we are mandated to have to pay) even though they were never supposed to be able to do that.
Hope that helps!
| [
"Critics of the system, such as Nobel Laureate economist Milton Friedman, have said that Social Security redistributes wealth from the poor to the wealthy. Workers must pay 12.4%, including a 6.2% employer contribution, on their wages below the Social Security Wage Base ($102,000 in 2008), but no tax on income in e... |
The Battle of Britain has ended and I've just turned 18. I want to join the RAF as a fighter pilot. What is the recruitment process like? If I were successful, how long would I be training for before my first flight into battle? | I can partially answer your question, but I think other people with more knowledge would be able to give you a little more information.
Initially, the RAF was very much an "an old boys club" and crew were expected to have attended public schools such as Eton. Although losses changed this very quickly and air crew were accepted from all backgrounds. (I would be speculating if I were to provide a time frame for this to have occurred.)
During the war, the Empire Air Training Scheme was producing pilots over about 2 years before crews would be shipped back to Europe for operational training.
After the Battle of Britain, pilots were channeled into bomber training because of the high loss rates and those rates increased for most of the war.
I hope that is of some use to you. Unfortunately, I am not as well read on fighter pilot training, but books like [Lancaster Men](_URL_0_) and [Battle order 204](_URL_1_) might give you some insight into aircrew training (albeit for bomber command aircrew). | [
"Prior to the outbreak of war, in view of the worsening European situation, the RAF had embarked on a series of expansion plans. These included Short-Service Commissions for pilots from the air forces of other British Commonwealth countries, namely Australia, Canada, New Zealand, South Africa and Southern Rhodesia.... |
why is a root canal preferable over say an extraction/implant? | Root canal or implants are not the only options. There's also the "old way", extraction and a dental appliance (dentures). The emphasis on keeping all your teeth is relatively new - in past times, dentists had no compunction about yanking problem teeth. Not all countries place such an emphasis on cosmetically-perfect teeth as the USA.
Dentures are much cheaper, but there's a problem: bone loss around the socket of the extracted tooth. Root canals and implants prevent this. However the costs involved in either procedure make it impractical for most average working people. | [
"The alternatives to root canal therapy include no treatment or tooth extraction. Following tooth extraction, options for prosthetic replacement may include dental implants, a fixed partial denture (commonly referred to as a 'bridge'), or a removable denture. There are risks to forgoing treatment, including pain, i... |
Has there ever been a time in history when white people have been persecuted because of their colour? | In Zimbabwe, after the end of apartheid, there have been a lot of incidents of white people being targeted because of their [race.](_URL_0_)
While kind of understandable because of the earlier apartheid situation it is whites being persecuted because of race.
| [
"BULLET::::- 1923 \"United States v. Bhagat Singh Thind\": Indians, despite being anthropologically Caucasian, were ruled to be non-white as they were not seen as white in the \"common understanding\", thus excluding non-U.S. born South Asians from citizenship under the racial prerequisites for naturalization at th... |
Did the Roman navy use heavy armor and shields or were they lightly armored? | Are you asking about marines or rowers? The vast majority of the people on any warship would be unarmed and unarmored rowers huddled below decks on their benches. Marines, however, were most certainly heavily armored and armed, that is well accepted. Both the Greeks and the Romans essentially employed exactly the same troops as would operate on land on board their ships--among the Romans even the organization of marine units mirrored legionary organization. We have multiple visual representations of marines, which are nearly indistinguishable from regular legionaries, and we have many literary references--Livy, for example, mentions Scipio using his marines alongside his infantry, without rearming them or anything. In ancient naval warfare purely ramming was rarely sufficient to sink a ship outright, and even so a ramming action would result in a tangle. Boarding actions are the norm, and both the Greeks and Romans employed heavy infantry as their marines--Thucydides, for example, rarely uses the word for marines (ἐπιβάτης) even when it's abundantly obvious that he must be referring to marines, but instead simply says hoplites. There's not really any debate on this--Thucydides, for example, gives us the compliments of rowers, crew, archers, and hoplites on board each trireme in the Athenian fleet, and we know that during the Principate marines were frequently used as regular infantry forces, as fleets were frequently posted away from legionary camps | [
"Armoured warships (dreadnought battleships, armoured cruisers and later light and heavy cruisers) of the early 20th century carried their main protective armour above the waterline – the \"main belt\" – which was intended to stop flat-trajectory gunfire from piercing the hull. Below the belt, the armour generally ... |
how do insurance companies like geico, progressive, etc. have so much money to spend on ads? | There are roughly 265 million vehicles on the road in the US. Roughly 87% of those vehicles are insured. That leaves you with about 230 million vehicles insured in the US.
There are approximately 6 million car wrecks a year in the US. I'm assuming some of those vehicles didn't even need to have insurance claims done. That leaves you about 225 million insured vehicles without a claim for a wreck. Factor in theft, weather damage, and shit like that, and I'll be generous saying another 50 million claims.
That's still 175 million vehicles on the road having insurance premiums paid every month for no fucking reason.
We havent even begun to discuss motorcycles, boats, RVs, houses, and all the other insurable shit that is out there that I would assume have roughly the same numbers.
If my math is correct, insurance companies have a metric fuck ton of money because all of us send them a few hundred bucks every month, and they give us exactly jack shit in return for months and months until the off chance we need 500 dollars to replace a fucking hubcap. | [
"Most of the revenue received by insurance companies consists of premiums, but revenue from investing the premiums forms an important source of profit for most life insurance companies. Group Insurance policies are an exception to this.\n",
"In the mid-1990's, insurance company advertising was considered novel an... |
Are there any theories on different ways to generate gravity besides having mass? | It's not *real* gravity, but one idea for *simulating* gravity (which would be useful for space ships and stations in a microgravity orbit: spin a circular disc around at a constant velocity to generate a centrifugal force, making the outside of the disc exert a normal force back on you to counteract it, thus simulating standing on the ground. The rate of rotation can be variable to adjust the amount of "fake" gravity.
Although it isn't real gravity per se, the centrifugal force is more like gravity than an actual force, in the sense that both gravity and the centrifugal force are fictitious forces which arise due to your frame of reference, and so neither force causes a proper acceleration as measured by an accelerometer. In other words, the centrifugal force should be (aside from the dynamics of how it is produced, or things like the direction of the gradient) indistinguishable from gravity, even by someone equipped with an accelerometer. | [
"Based on observational evidence, it is now known that gravity interacts with all forms of energy, and not just with mass. The electrostatic binding energy of the nucleus, the energy of weak interactions in the nucleus, and the kinetic energy of electrons in atoms, all contribute to the gravitational mass of an ato... |
Does dreaming have any effect on the qualify of sleep? | Dreaming occurs during the R.E.M. cycle of sleep, the most important aspect of it. [This question](_URL_0_) also hinges around the same area that you are prodding at, as there is information there as well.
As far as dreaming having a DIRECT effect on quality of sleep, that answer has yet to be supported or rejected. Very little is actually known about sleep. But, from what we do know, dreaming is most likely a product of our subconscious that is released during R.E.M. | [
"In a study conducted with depressed and healthy adults and were able to show that in healthy subjects, dreaming was a way to positively influence mood and cope with stress at night. Dreams of depressed persons, however, might deteriorate their mood further. This study's interesting results are limited in generaliz... |
why are sit-ups harder to do with your hands behind your head, rather then free? | Have you ever looked at a teeter-totter before? If one person on the teeter-totter is sitting at the very end and person on other side is sitting closer to the middle, then there's an imbalance and that imbalance spreads outward from the middle, which is called the fulcrum. Even though the two people may weigh the same amount, it's almost as if the person that's further away from the middle is heavier. When doing a sit-up, the middle of your body (your hips, waist, and butt) would be like a fulcrum. By placing your hands behind your head, you're putting more weight at the very end and that impacts the amount of effort you have to expend when you do your sit-up. This is caused by gravity. The further out on the end the weight is located, the more it has to fight against gravity and rise above the ground. | [
"2 point players need to put one hand on their chair's wheel for stability when trying to rebound. This is because of stability issues. When pushing themselves around the court, they do not require the back of their chair to maintain stable forward movement.\n",
"Sitting problems are usually an invisible disabili... |
why is quarantining for a few weeks so effective? wouldn't it just start spreading just as bad as soon as the quarantine ends? | Viruses, like all living things, need to reproduce to survive. They do so by infecting an animal (or sometimes even a bacteria) and taking over its cells to replicate. By people who have the virus quarantining for an extended period of time, the hope is that they recover and develop the antibodies to fight off the virus. This kills the remaining virus in their bodies, and eventually any remnants of the virus they’ve spread to their surroundings will die since they haven’t found a new, vulnerable animal to help them reproduce. | [
"Quarantine periods can be very short, such as in the case of a suspected anthrax attack, in which persons are allowed to leave as soon as they shed their potentially contaminated garments and undergo a decontamination shower. For example, an article entitled \"Daily News workers quarantined\" describes a brief qua... |
why does it feel like there's less viruses on the internet nowadays? | *Fewer
And the purpose of viruses has shifted from being some piece of code that just fucks your system up, to being motivated by money. Modern malware is mostly targeted at businesses, websites, banks, etc. The home user isn't really a lucrative target. There are still viruses out there, but most end user AV software is good enough now to keep most of it from ever affecting you. The major hackers want to exploit databases to steal information from a business to ransom it or sell it, steal millions of credit card numbers at once, or other attacks that can make them a lot of money. There isn't much money to be made in having your individual home PC break. There are still viruses out there, and they can affect your computer, but you AV will *probably* detect it, along with safer browsing habits. | [
"Computer viruses currently cause billions of dollars' worth of economic damage each year, due to causing system failure, wasting computer resources, corrupting data, increasing maintenance costs, etc. In response, free, open-source antivirus tools have been developed, and an industry of antivirus software has crop... |
why do boxers get paid so much? | If anything, why do athletes get paid so much? | [
"There were speculations that ring girls are paid more than some female athletes. In 2015, former UFC bamtamweight champion Ronda Rousey protested. \"Do you think her walking in circles, \" argued Rousey, \"is worth more (than fighters)? ... either the ring card girls are paid too much, or the fighters aren't paid ... |
What is the difference between amplitude (volume) and loudness? | Amplitude is a feature of a signal, usually periodic signals like sine-waves. It is a measurement of the 'height' of the signal, the distance from the lowest point to the highest in whatever units the signal is in. If we were measuring the signal sent to the speakers, it would be measured in Volts, or if we measured the signal 'in the air' it would be in something like sound-pressure.
'Loudness' is about perception. Whether one sound is louder than another depends on the whole process of sound interacting with the various parts of your ear, how that stimulates nerves (and by what degree), and then how your brain interprets that stimulation.
It's the same kind of difference between the amplitude of light from a bulb (in lumens?) as compared to how bright the bulb looks. To stretch things a bit, it's like how much sugar is in some drink as compared to how sweet it tastes. | [
"Amplitude is the size of the pressure variations in a sound wave, and primarily determines the loudness with which the sound is perceived. In a sinusoidal function such as formula_1, \"C\" represents the amplitude of the sound wave.\n",
"The amplitude of sound waves and audio signals (which relates to the volume... |
why do musicians (famous and average) choose to publish music through record label companies, as opposed to going to pandora/spotify/itunes radio/all the others directly? | For a lot of musicians, it's still easier to let someone else handle all of the details of dealing with distribution, marketing, and production. And since record labels have been doing this for a long time, they tend to have the resources to handle all of that pretty efficiently.
Record labels probably take more than most bands would like, and are stingier about licensing and pricing that most music providers and end users would like, but that's true of most middle-man style businesses (like book publishers)
There are plenty of bands who do try to skip the middle man, but it's a lot of work for bands that are not well known. Already successful bands can afford to just let record labels deal with it.
There are examples of bands that buck the trend. Nine Inch Nails has famously (infamously?) split from its record label and does most of its own distribution etc. | [
"Musical performers often self-release (self-publish) their recordings without the involvement of an established record label. While some acts who enjoy local or small scale popularity have started their own labels in order to release their music through stores, others simply sell the music directly to customers, f... |
During WWII, did German U-boats attack ships traveling from the UK to the US as well? | Yes, westbound convoys were attacked, often just as heavily as ones heading eastwards. The goal of the German submarine offensive was to reduce the amount of merchant shipping available to the Allies. If it could be reduced far enough, then Britain would not be able to import the supplies it needed to fight the war and the food it needed to feed its population. As such, convoys heading both ways were attacked - sinking supplies on eastbound convoys was just a bonus. Westbound convoys were escorted just as heavily as eastbound ones, and there were a number of significant convoy battles that formed around such convoys. In 1941, the westbound convoy OB 318 was attacked by a German wolfpack. One of these U-boats, *U-110*, was forced to the surface by the British escorts and captured (though she would sink while being towed to Iceland). Aboard her was an Enigma machine and a number of important documents, which greatly eased Bletchley Park's attack on the Naval Enigma. During the climactic battles of 1943, which broke the back of the U-boat force, the largest battle was that around the westward convoy ONS 5. During this battle, 13 merchants were sunk, in return for 7 U-boats. | [
"At sea, German U-boat (submarine) forces were taking a considerable toll on Allied shipping. The Air Ministry decided to launch an attack on German surface ships to prevent them supporting the U-boats in the North Atlantic. On 18 December 1939, a force of three RAF bomber squadrons was sent to engage German ships ... |
What do emission spectra reveal about stars? | As you've already recognised, we can deduce the composition of a star from the spectra, assuming we know enough about the placement and surroundings to compensate for various shifts. From this we can classify the star, and with just a bit more information about their luminosity, we can more or less pin down what type of star it is; this is to say, we would know more or less how old the star is, how big it is, and what stage of stellar evolution it is in. For an overview of stellar evolution, see the Hertzsprung Russell diagram:
_URL_0_
It will also serve to help us find out how far away the star is.
If we happen to know a lot about a particular stellar spectra for whatever reason, we can also use this to tell us more about the material between us and the star. There are a few ways, for example, that we can deduce the total magnetic field of the material between the star as us. This can get very, very, very complicated, but if you're interested, the term to point you in the right direction is 'faraday rotation'.
Another application would help tell us about surrounding objects, if we examine those shifts. There are a lot of different places shifts can come from, so it can get pretty confusing sometimes; cosmological redshift is caused by the sheer distance between us and the star, then there's peculiar velocity, caused by the true velocity of the object. Then of course, our own motion can create and effect, and we can also measure gravitational redshift.
Spectra alone can't tell you an enormous amount, but with just a bit of extra information about the surrounding area, luminosity etc, you can do alot. | [
"In 1994, several stars were identified as having broad helium emission lines in their spectra, and some showed narrow hydrogen emission lines. This was completely unexpected for protostars, instead suggesting the objects were much more evolved stars. Shortly afterwards two emission line stars were classified as Wo... |
Obviously spices were central, but to what degree were drugs included in "the spice trade"? | Opium is your answer. Go look into that. | [
"The spice trade refers to the trade between historical civilizations in Asia, Northeast Africa and Europe. Spices such as cinnamon, cassia, cardamom, ginger, pepper, and turmeric were known and used in antiquity for commerce in the Eastern World. These spices found their way into the Middle East before the beginni... |
is there a way commercial banks are creating their own money (digital or paper) without anyone knowing? | Okay, this is going to be complicated, but bear with me.
Economists have names for different types of money. M0 is the sum of all the dollars bills and coins printed by the treasury. Banks do not increase the M0 supply.
But there are several other types of money that economists count - traveller's checks, demand notes, saving accounts, money market accounts, etc. Depending on what types of things are included, [these are known as M1, M2, and M3](_URL_1_). It turns out that banks can increase the M1, M2, and M3 money supplies.
The most important way they do this is to give out loans. Let's say I take a dollar and put it into a bank. By law, they have to put a certain percent of that in the vault. Let's say, for the purpose of this example, it's 10%. (In reality, I think [it's either 10% or 3% depending on the size of the bank](_URL_2_)\). The bank takes the other 90 cents of my dollar, and lends it out, and it gets spent. Then someone else deposits it. The bank takes the 90 cents, puts 10% away, and loans out the other 81 cents. It gets spent, redeposited, and another 72 cents gets lent out. Wash, rinse, and repeat. Eventually, that one dollar becomes ten dollars. That's the main method for how banks create money.
More details: _URL_0_ | [
"In the late twentieth century advances in computer and photocopy technology made it possible for people without sophisticated training to easily copy currency. In an attempt to prevent this, banks have sought to add filtering features to the software and hardware available to the public that senses features of cur... |
what causes eyes to get fatigued from reading for too long? | We actually have muscles in our eyes. These muscles constrict and relax to change the shape of the lens, which is how our eyes focus. Reading or looking at a screen for long periods of time requires these muscles to hold themselves in specific position in order to focus on what we're looking at. We also have muscles that control our eye movements, and they have to work to keep our eyes pointed in the right direction and moving at the right pace to read. Like any muscles that's overworked, they get tired. That's why it's recommended that people who spend a lot of time reading or working with screens take breaks at least every 30 minutes and look at something further away for a bit. This gives these muscles a chance to relax. | [
"Primary reasons is eye fatigue as a result of excessive pressure on the eyes because of reading, watching TV, computer, poor lighting, etc. Some other reasons are poor posture, poor diet, lack of sleep, etc.\n",
"When the eyes dry out or become fatigued due to reading on a computer screen, it can be an indicatio... |
How did the Romance language-speaking enclaves in former Dacia survive amongst Slavs, and how did they expand to the borders of modern-day Romania? | The people speaking Proto-Romanian, the ancestor of Romanian language, are thought to have lived in a rather small area, hence the distinctive lack of dialects of Romanian (with the exception of Aromanian and other southern dialects which have split around a thousand years ago).
The exact area where they lived is a matter of debate (and since this is Southeastern Europe, politics mixes with history), but generally it's thought to be around the mountainous regions of Transylvania and/or Banat.
These mountaineer Romanians were mostly shepherds and they were very mobile (with some exceptions, not quite nomadic, but close to it). They easily spread from the mountains of northern Greece to what is now Czechia.
The Slavs, on the other hand, traditionally inhabited the lowlands (their Urheimat was most likely in the plains of Ukraine-Poland-Belarus), so at first, there was little overlap in territory. They settled in small villages in the steppes and still-forested plains.
An increase in the Romanian population meant they began to settle downwards, in the plains. In Romania, the population density of the plains was still very low, meaning that assimilation by the Romanians was easily done. In other areas (Slovakia, Bulgaria, Bosnia, Croatia, Montenegro), the Romanians were relatively few in number compared to the Slavic population, so the assimilation was the other way around.
----
Even to this day there are pockets of "Vlachs" (Romanian and Aromanian-speaking people) across the Balkans who are still shepherds. In some languages (including Greek), the word "Vlach" is synonymous with "shepherd".
| [
"A number of Romance languages were once spoken in Southeastern Europe for centuries, but the Dalmatian branch of this Eastern Romance disappeared centuries ago. Although the surviving Eastern group of Balkan Romance has in the meantime split into four major languages, their common features suggest that all of them... |
what does it mean to have something notarized? | A document that's been notarized has been approved by an a neutral and trusted public official called a notary public. Basically it means the notary witnesses and confirms the identity of the person or persons signing the document and that they understand what the document does so there's no question later as to its validity. This is usually required for documents that you really don't want questioned, like property deeds, wills, and powers of attorney. | [
"An accusative and infinitive can also be used to express a piece of information which someone has been told, or by extension which someone has learnt about, noticed, realised, seen, dreamed of, perceived or simply knows:\n",
"In predicate logic, what is described in layman's terms as \"something\" can more speci... |
if we created a magnet that was say 1 inch in diameter and was a kilometer long, is it possible we can create monopoles on each end (north side doesnt connect to south side) | by definition, no.
every north and south side of the magnet will connect. If the magnet is 1 long magnet of uniform orientation, than thats what it will be.
If you force opposite poles together, or separate magnets with a non magnet filler, then your just moving the goal posts, but each magnetic segment will pair north to south, with interference's from the other segments. | [
"Magnetic monopoles can be theoretically realized, although current observations and theory are consistent with them existing or not existing. Electric and magnetic charges can effectively be \"rotated into one another\" by a duality transformation.\n",
"In a multipolar generator, the armature and field magnets a... |
What did Augustus (Roman Emperor) read and study growing up that prepared him for office | In terms of direct evidence for Augustus himself, we only have a very short description of his education in Suetonius (Life Of Augustus 84):
"From early youth he devoted himself eagerly and with utmost diligence to oratory and liberal studies. During the war at Mutina, amid such a press of affairs, he is said to have read, written and declaimed every day."
Suetonius also describes Augustus' literary tastes, from which we can infer some further information about his education (Life of Augustus 85):
"He wrote numerous works of various kinds in prose, some of which he read to a group of his intimate friends, as others did in a lecture-room; for example, his "Reply to Brutus on Cato." At the reading of these volumes he had all but come to the end, when he grew tired and handed them to Tiberius to finish, for he was well on in years. He also wrote "Exhortations to Philosophy" and some volumes of an Autobiography, giving an account of his life in thirteen books up to the time of the Cantabrian war, but no farther. His essays in poetry were but slight. One book has come down to us written in hexameter verse, of which the subject and the title is "Sicily." There is another, equally brief, of "Epigrams," which he composed for the most part at the time of the bath. Though he began a tragedy with much enthusiasm, he destroyed it because his style did not satisfy him, and when some of his friends asked him what in the world had become of Ajax, he answered that "his Ajax had fallen on his sponge"."
From these two sections it's fairly clear that Augustus was educated in oratory, philosophy and literature, certainly in both Greek and Latin. If he was writing a trajedy about Ajax he must've read Sophocles and Homer, and if he was writing about philosophy then he probably also read the Greek masters: Plato, Aristotle etc. In this he would have been fairly typical of young men of his social class, all of whom would have received schooling in these subjects. Saying anything more about Augustus himself is speculation, but we can say something about elite education in late Republican Rome and tentatively apply it to him.
Cicero gives a fairly detailed account of his oratorical training in the Brutus (301ff.), and also discusses education in this section of de Oratore (1.158-9):
"The poets must also be studied; an acquaintance must be formed with history; the writers and teachers in all the liberal arts and sciences must be read... The civil law must be thoroughly studied; laws in general must be understood; all antiquity must be known; the usages of the senate, the nature of our government, the rights of our allies, our treaties and convention, and whatever concerns the interests of the state, must be learned."
Cicero says that he learned from the best men in the city at the time - he trained with the top orators and legal minds, and studied with a number of Greek philosophers living in Rome. He also travelled to the Greek world to further his studies, including Athens. Whether the same can be said for Augustus is uncertain, but there's no doubt that his family connections would've made it possible. | [
"Augustus is an epistolary, historical fiction by John Williams published by Viking Press in 1972. It tells the story of Augustus, emperor of Rome, from his youth through old age. The book is divided into two parts, the beginning chronicling his rise to power, the latter describing his rule thereafter, and the fami... |
Great Grandpa was official photographer for WW2, recently found a torture picture and POW. Anyway to find out more info? | Hello there! You're right, we don't have a lot of desire to host pictures of people being tortured.
As your question is related to looking for identification/information regarding military personnel, our [Guide on Military Identification](_URL_0_) may be of use to you. It provides a number of different resources, including how to request service records from a number of national agencies around the world, as well as graphical aids to assist in deciphering rank, unit, and other forms of badges or insignia. While the users here may still be able to lend you more assistance, hopefully this will provide a good place to start! | [
"In 2009, the film, \"Toyo's Camera\" was released, documenting the internment of Japanese Americans during World War II through the perspective of the photographer's images. Narrated by George Takei, music by Kitaro.\n",
"The book describes the backgrounds of several American airmen who flew raids over Japan dur... |
how can the bootes void, or the great void as it is sometimes called, be filled with stars and galaxies and still be called a void? | Because our definition of "void" (in regards to space) is not just _URL_0_ just means less than average density of matter compared to the rest of the observable universe. | [
"The Boötes void (or The Great Nothing) is an enormous, approximately spherical region of space, containing very few galaxies. It is located in the vicinity of the constellation Boötes, hence its name. Its center is located at approximately right ascension and declination .\n",
"BULLET::::- The Void is the name g... |
why don't more companies collaborate on everything? | Because if there is no competition, your company doesn't have the chance to win more money than the rest. It's like the prisoner's dilemma:
_URL_0_ | [
"Usually, firms that promote open forms of collaboration benefit from having access to different capabilities and knowledge, enhancing their competitiveness and accelerating their innovation process. On one hand, it enables small companies such as start-ups to partner with other players, complementing each other an... |
Will all stars in the universe die eventually? | Stars form from the free gas floating in the galaxy. This gas condenses and collapses into star clusters. Each star cluster has a mix of stars of different masses.
The most massive stars will explode as supernovae, throwing a lot of gas back into the galaxy, which can then mix around and collapse and form new stars. However, these stars don't throw *all* of their gas back - they keep a large amount of it in the core, as a remnant neutron star or black hole. These stars also explode very quickly - they only live for millions of years, and our universe is billions of years old.
Somewhat less massive stars (like our Sun) will have a less dramatic explosions. They blow off their outer layers to form a "planetary nebula". Again, this gas can spread out through the galaxy, but it's only a fraction of the mass of the star. The rest is retained in a compact White Dwarf.
Very small stars won't really explode at all. They are also extremely long lived. Red dwarfs will survive for *trillions* of years before running out of fuel - much longer than the age of the universe.
Overall, what this means is that when you form stars, you don't get all that gas back to form new stars. A lot of it ends up trapped in compact remnant objects like neutron stars, black holes, and white dwarfs. Much of the rest ends up stuck in red dwarf stars that are so long lived that none have yet died in the entire history of the universe. So, eventually, you will run out of gas, and we will stop forming new stars. We're already past the peak of star formation, but there's still plenty of gas to keep a slow burn of star formation running for a long time. And, eventually, even the red dwarfs will burn out and start collapsing into white dwarfs, and then cooling into black dwarfs.
So, there is a sort of cycle, but it's a leaky cycle, and we will run out of stars eventually. | [
"The most massive stars that exist today may be completely destroyed by a supernova with an energy greatly exceeding its gravitational binding energy. This rare event, caused by pair-instability, leaves behind no black hole remnant. In the past history of the universe, some stars were even larger than the largest t... |
How does wasp and hornet killer work? | I fucking hate bees, but at the same time I must acknowledge the vital role they play in pollinating things. So I guess it's a love-hate relationship we've got going.
Many of the more popular wasp & hornet sprays use resmethrin (an insecticide of the [pyrethroid](_URL_0_) family). The insect exoskeleton is rather porous to this family of insecticides and so it gets to their vital bits pretty quickly. It works by fucking with their sodium channels, and keeping them stuck open. You see, in order to function properly, a cell needs to very tightly control the concentration of sodium on the inside.
In laymans terms, this is kinda like the doorman at a late-night club. You want ladies in the club, but not too many ladies, or else there will be too many screaming bitches at the bar and/or crowding the dance floor. Pretty quickly, with too may ladies, the bar bursts into flames and burns down. So, you must maintain the proper amount of ladies in the club in order for the optimal fun to be had. Now, the insecticide rolls up in her fancy stretch limo, and effectively distracts the doorman keeping his hands busy, so all the ladies rush into the club.
The reason these insecticides aren't too bad for humans is because we have some special enzymes floating around that gobble up the insecticide before she can wrap her skanky thighs around the doorman.
Lots of different insecticides usually work like this. By finding a critical target in insect cells that at the same time isn't too toxic to vertebrates, you've got yourself a marketable bee killer. | [
"Killer Wasp is a human/insect hybrid. He has enhanced strength, agility and endurance. He also has wasp-like wings on his back which allow him to fly up to speeds of 50 mph, and the ability to shoot electrical blasts from his hands.\n",
"Cicada killer wasps frequently attack \"Neotibicen\" cicadas. The female wa... |
- could someone explain to me the ethical theories of plato, aristotle, kant and mill by giving examples? | Plato: The well-being of the soul *("eudaimon")* is the highest goal of thought and action. This is achieved when each member of society commits to his *ergon*, his natural duty. Batman's natural duty is to protect the common good. Thus Batman's obligation to himself leads to an obligation to his *ergon*, which compels him to kill the Joker.
Aristotle: *Eudaimonia* arises from virtuous action. Virtuous action is action which arises from *enkrateia* (mastery of the self) rather than *akrasia* (lack of self-mastery). *Akrasia* arises from *pathos*, or emotion, while *enkrateia* arises from rationality and self-discipline. Therefore Batman's obligation to his *enkrateia* compels him *not* to kill the Joker.
Kant: Ethical action is that which arises not just from reason alone, but from duty. We have duties to the civil law, to the moral law, to the hypothetical imperative and to the categorical imperative. Both civil and moral law instantiate the hypothetical imperative that one should not kill a person when other options remain available. Therefore Batman's duty to the civil and moral law compels him *not* to kill the Joker.
Mill: Actions are right in proportion to their tendency to promote happiness; therefore, actions must be prejudged by their anticipated consequences. The consequence of killing the Joker would be the absolute prevention of the Joker's causing unhappiness in the future, balanced against the possibility of creating a vacuum into which another figure would rise to create greater unhappiness, balanced against the deterrent effect of the Joker's killing. Therefore, Batman should torture the Joker to death slowly on live television, stopping periodically to turn to the camera and growl "This is what will happen to you if you step out of line." | [
"Aristotle considered ethics to be a practical rather than theoretical study, i.e., one aimed at becoming good and doing good rather than knowing for its own sake. He wrote several treatises on ethics, including most notably, the \"Nicomachean Ethics\".\n",
"Kant's philosophy marks a number of important conceptua... |
Where does the heat from the Earth go? | Well, into space... | [
"Earth heat transport occurs by conduction, mantle convection, hydrothermal convection, and volcanic advection. Earth's internal heat flow to the surface is thought to be 80% due to mantle convection, with the remaining heat mostly originating in the Earth's crust, with about 1% due to volcanic activity, earthquake... |
how do rocks (track ballast) able to support a train? | 1) I assume the gravel is compressed when it is installed, e.g. with a heavy roller and/or a vibrating plate, so that if it's going to move down and fill a hole then it does that while it's being installed, not when a train is on it.
2) The rails and sleepers do a good job of spreading out the load. While a car only touches the ground in 4 small spots at the base of each tyre, with a train the load from the wheels is spread out first along the tracks by the rails, then across the tracks by the sleepers.
3) The rails and sleepers aren't moving. Driving cars along a gravel track will tend to dig out gravel from under the wheels as the wheels slip and push gravel out backwards; that doesn't happen with a railway track because the train wheels only touch the rail not the gravel.
4) The railway line does get maintenance occasionally; this will presumably include filling in any low spots in the ballast. There are special trains they run along the tracks to look for places where the rail has moved, so they can schedule maintenance. | [
"Track ballast forms the trackbed upon which railroad ties (sleepers) are laid. It is packed between, below, and around the ties. It is used to bear the load from the railroad ties, to facilitate drainage of water, and also to keep down vegetation that might interfere with the track structure. This also serves to h... |
How long can you survive drinking only water distilled from your own urine? | Well, you also will have fluid losses other than urinary evacuation (sweating, water vapor in your breath), if the system is closed, ie no additional water is added, you will run out.
On a related note, I have read that drinking the water from a healthy bladder is acceptable, purportedly certain eskimo cultures do it as a matter of course in the wintry extremes. | [
"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... |
why are most houses that were made recently so ugly? | The first reason is survivorship bias. There were tons of ugly buildings in the 50s. For example [Nissen huts](_URL_0_) were a cheep and fast way to build and ugly ass garage or barn and were very popular until the 60-70's. You don't see many today because people tore them down whenever they got the chance and replaced them with something less ugly.
The second thing is that mcmansion style houses are often built on the cheep to give off the illusion of having much more wealth than one actually has. They're made of the worst materials as fast as possible and with as little aesthetic input as possible. Its all about how quickly and how large it can be made and not much else. Many beautiful homes are still being made today but by the very nature of what a mcmansion is (cheep and fast to construct) you're always going to see more of them.
The third thing is that 90% of everything is crap especially when its new. Those houses from the 50s have had a lot of time to come into themselves and remove flavor of the month items. You're seeing them after decades of development and refinement when for all we know when it was first constructed it could have had a bright pink enamel everything kitchen and green felt over every concert outdoor surface as was the style of the time. | [
"In the present scenario, these houses are now endangered and are hardly built due to the adaptation of modern architecture. Also the reason that the poor house owner are unable to bear expenses for wood carvings for the embroideries, thus resulting in the extinction of local craftsmen and hence the traditional des... |
Have there ever been proposed additions to the English alphabet? | The two most notable ones off the top of my head were thorn (which got replaced by combining t and h) and ash (**EDIT:** which is apparently NOT related to the mushed together AE that pops up still in fancy spellings of encyclopedia.)
Wikipedia has a [surprisingly robust article](_URL_1_) about this.
As for proposed deletions, check out some of the ill-fated [English spelling reform efforts](_URL_0_). Obviously the overlap between K and C, and then C and S, is ripe for the picking, and we could theoretically make due with just K and S. | [
"It was originally published in June 1845. Subsequently, adaptations were published which extended the alphabet to the German, Arabic, Spanish, Tuscan, French, Welsh, Italian, Dutch, Polish, Portuguese and Sanskrit languages.\n",
"The modern English alphabet is a Latin alphabet consisting of 26 letters, each havi... |
Is the sun soft or hard? | To use your terminology, the edge of the Sun is rather soft. Take a look at [this graph of the matter density profile of the Sun](_URL_1_). Close to what we usually take to be the edge of the Sun, the density is about 10^(-4) g/cm^(3). This density is comparable to the density of our atmosphere on Earth at ground level. However, as you go deeper and deeper the density rises, until you get to the core where densities are on the order of 10^(2) g/cm^(3), which is about 10 times as dense as bulk gold.
Of course, like you say this doesn't mean you have any chance of sailing through anywhere close to the core. The temperature is already thousands of K at the edge of the Sun and [quickly rises until it reaches more than a million K near the core](_URL_0_). If that wasn't enough, you also have to deal with some [utterly crushing pressures](_URL_2_). For example, close to the core, pressures rise upwards of 10^(15)Pa, a pressure higher than what you may find at the center of the blast of a thermonuclear warhead. Needless to say no material we could dream up could withstand these conditions.
Sources: The graphs are from [here](_URL_4_) and the orders of magnitude from [Wikipedia](_URL_3_) | [
"14 Boötis has 1.46 times the mass of the Sun and 2.1 times the Sun's radius. It is radiating 5.9 times the luminosity of the Sun from its photosphere at an effective temperature of 6,169 K. The metallicity is near solar, based on the abundance of iron in the stellar atmosphere.\n",
"As described in the Sun artic... |
What was the endgame for the Soviet Union in the Cold War? | I think that question is too far raging, and it'd be better served as something more focused, its a little bit like asking:
What is the US endgame in the 21st century? Does it involve an eventual military conflict?
If you're interested National Interest's Robert Farley and Zachary Keck made a couple of articles about Soviet war plans up until the 70's-ish based on available NATO info and declassified Polish and Czech documents:
_URL_3_
_URL_1_
_URL_0_
Also you might be interested in in the FAQ section dealing with general Soviet thoughts and perspectives, I particularly recommend the article asking about a "soviet James Bond", the answer, by /u/Bufus is very detailed and might help you to get an overview of soviet general mentality at the time (I know it did for me), which is to say, VERY different from the US one:
_URL_2_ | [
"The Cold War was a state of political and military tension after World War II led by the United States (and the Western Bloc) and the Soviet Union (and the Eastern Bloc). After World War II, the victory of the Soviet Union over Germany granted them considerable territorial spoils; the Soviet Union banded together ... |
what would happen if an illegal immigrant claimed that she had always lived in that country and had simply lost her id? even if they didn't believe her, what country would they deport her to if they didn't know? and if she had no money, would they just keep her locked up forever? | I don't understand why people are failing to understand Stallone2's question. I think it's essentially:
If the authorities think a person is an illegal immigrant they usually deport them to their country of origin.
If no country of origin can be established, what happens? | [
"In 1929, within eight months of attaining the age of majority, Marie Elg obtained an American passport through the American consul in Sweden, and returned to the United States. In 1935 she was notified by the U.S. Department of Labor that she was an illegal alien and was threatened with deportation.\n",
"One cas... |
How fast does something have to travel in earths atmosphere before it begins to heat up? | When the air is hits an object going through it, it gets warmer, because kinetic energy energy gets converted to heat.
This also applies to your hand out of the car window scenario, however it is only about [0.4°C](_URL_1_) (assuming 100km/h speed; 20°C ambient temperature). However, in this case, your hand feeling colder is due to the airstream removing heat energy from your hand (assuming your hand is warmer than ambient temperature) and evaporative cooling from sweat on your hand. The same effects occur when you switch on a fan, the coom temperature does not change (technically it does increase slightly, as the fan adds energy to the room), but you'll feel cooler.
[Total air Temperature](_URL_0_), i.e. the temperature of the air"stream" after ist has been brought to a sudden stop, is actually measured in (jet) aircraft. | [
"Traveling at approximately 6.9 kilometers/second and 125 kilometers above the surface, the spacecraft entered the atmosphere and was initially decelerated by using a 2.4 meter ablation heat shield, located on the bottom of the entry body, to aerobrake through 116 kilometers of the atmosphere. Three minutes after e... |
If you took a breath of pure oxygen could you hold your breath longer than if you took a breath of normal air? | Yes. I'm an anaesthetist - When someone is anaesthetised it is common practice to "pre-oxygenate", ie give 100% oxygen for around 3 minutes via a tight fitting face mask. This gives a margin of safety after induction, in case there is some disaster and there's a failure to ventilate.
The idea of pre-oxygenation is to replace air in the Functional Residual Capacity (that is the residual volume of air in the lungs after the end of a normal breath) with 100% oxygen. The volume of the FRC in a 70kg adult is about 2.5 litres. The total oxygen demand of the same person at rest is about 250ml/min. With no pre-oxygenation the total amount of oxygen in the FRC will be 500ml (2.5L * 21%) - exhausted in approx 2 min. With pre-oxygenation you can increase the time until your lung stores of oxygen are depleted by about 5 times to 10 minutes.
In that 10 minutes, arterial CO2 levels will climb by about 0.5 kPa/min, from about 5 kPa to 10, the blood pH will probably drop to about 7.2. This is not ideal, but it really isn't life threatening. Lack of oxygen will kill you way before the build up of CO2 does.
The caveat to that is that the urge to breath is predominately driven by CO2 build up, and inhaling one breath of O2 wouldn't do anything much to your CO2 levels so it would be difficult to resist your urge to breath, although probably not impossible with enough will power. | [
"According to the U.S. Chemical Safety and Hazard Investigation Board, in humans, \"breathing an oxygen deficient atmosphere can have serious and immediate effects, including unconsciousness after only one or two breaths. The exposed person has no warning and cannot sense that the oxygen level is too low.\" In the ... |
How do one way hashes work? | A one-way hash is a function which is easy to calculate forwards, but difficult to invert.
For example, SHA256 is conjectured to be a one-way hash function. An easy way to see the SHA256 hash of any string is to use an online calculator like this one: _URL_4_
If you have an input, say 'flopdood', then you can easily put that in and see the hash: 4cd4aee8ae42396f7b226fb1be20ff839778afb29ea05200c7f3e69d2cdd0104
But, if I give you a hash output, can you find the input?
One strategy to reverse a hash is to just guess inputs until you find one that gives you the desired output. This strategy always works, but if the input was random, then it's pretty inefficient. If you wanted to invert a random SHA256 output with this strategy, it would take basically forever. See this video for an illustration of how much time this would take: _URL_3_
If you happen to have a good idea of what the input should be, then you can invert the hash much more easily. For example, if you see a hash output of 'ae42396f7b226fb1be20ff839778afb29ea05200c7f3e69d2cdd0104', then you know the input was 'flopdood', since I showed you the other direction earlier in this comment. But if you have no idea what the input is, then you're stuck making random guesses.
But what if there's some clever algorithm that lets you calculate the inverse of a hash faster than just randomly guessing inputs? Then that hash function is not one-way!
We don't know for sure that SHA256 is one-way. But so far, no one has publicly inverted a random SHA256 output. Bitcoin actually relies on SHA256 being a one-way function in a few ways, so if someone did know an algorithm to invert it, they might be able to get free money. SHA256 is also used in HTTPS encryption (over which people send bank details, etc). Since there are monetary incentives for people to break these, and we haven't seen anyone break them, it gives some confidence that they aren't broken. But it's not for certain.
In fact, there is *no* function so far that has been proven to be one-way. The existence of one-way functions is still an open question in computability theory. It might be the case that no function is one-way. (For example, if P=NP, then one-way functions cannot exist. If P!=NP, then maybe one-way functions exist, but it's also possible that P!=NP and there are still no one-way functions.)
Here are some wiki links if you want to do some further reading:
- _URL_0_
- _URL_2_
- _URL_1_ | [
"Hashing is used in database systems as a method to protect sensitive data such as passwords; however it is also used to improve the efficiency of database referencing. Inputted data is manipulated by a hashing algorithm. The hashing algorithm converts the inputted data into a string of fixed length that can then b... |
How can we tell if a trait a characteristic about a person is genetic or environmental? | You might want to take a look at [epigenetics](_URL_0_), which is a study of where the rubber of genetics meets the road of environment.
Basically *biological functions* are entirely due to protein activity. Protein activity is influenced by many factors, but the big ones are genetic and environmental. Protein activity can also be measured in different ways. How many, how active, in how many cells, how permeable to various membranes, etc. | [
"For any trait of interest, observed differences among individuals \"may be due to differences in the genes\" coding for a trait or \"the result of variation in environmental condition\". This variability is due to gene-environment interactions that influence genetic expression patterns and trait heritability.\n",
... |
Did monotheism only develop in the ancient Near East (Akhenaten, Zoroaster, Judaism, etcetera), or have there been other instances of it in other parts of the world? | Your question almost answers itself, because a presumed historical Zoroaster (who we will for convenience define as the composer of the Gathas) would definitely not have lived in the Near East. Instead linguistic and textual evidence suggests he would have been from _Bactria_ or thereabout, roughly in modern-day Afghanistan. (Among other things, Pashto is thought to be the modern-day language closest to Avestan, and an episode describes Zoroaster interacting with the king of Bactria).
Anyway, any attempt to answer this question will invariably stumble into a big issue: monotheism is a statement of _doctrine_ moreso than a factual description of a religion. Case in point, some conservative Muslims do not view Christianity as truly monotheistic due to the whole Trinity business. If we consider Zoroastrianism as a monotheistic religion in its (I'm simplifying a bit and skipping some historical ambiguities here for brevity) exaltation of Ahura Mazda to the status of supreme being and relegating of other deities to the status of "Daeva" (roughly demons) or "Mainyu" (roughly spirits; the benevolent _spenta mainyu_ are aspects of Ahura Mazda, opposed to _angra mainyu_, the spirit of destruction) to be a statement of monotheism, should we not also do the same with Hindu traditions like Vaishnavism or Shaivism, exalting Vishnu or Shiva respectively?
I think monotheism is an unhelpful label, generally. It is a doctrinal self-identifier to differentiate oneself from one's perception of other religions. It may not even make sense at all in some intellectual/spiritual traditions and might even be an obstacle in understanding them on their own terms. Many of those from a Judaeo-Christian background enjoy waxing lyrical about the supposedly unique conditions experienced by the Hebrews leading to the exclusive worship of Yahweh, but that is with 2,500 years of hindsight, having seen Christianity and Islam conquer much of the world previously ruled by the "others", the "polytheists". We easily feel like there's something special about it that really sets it apart and demands explanation - it seems like a _development_, or _progress_.
But this is a narrow, Abrahamitic-centric way of viewing the world that risks inhibiting our appreciation for other religious-intellectual traditions, such as Buddhism, which has a very different relationship to the divine. These traditions have their own perspectives, frameworks and idiosyncracies, that distinguish them from others. Some may have something we may feel to be comparable to monotheism, but we need to be very careful indeed with the labels we apply. | [
"Alleged traces of primitive monotheism were located in the deities Assyrian Ashur and Marduk, and Hebrew YHWH. Monotheism in Schmidt's view is the \"natural\" form of theism, which was later overlaid and \"degraded\" by polytheism after deceased ancestors' veneration became worship, and personified natural forces ... |
why do i have an explosive bowel movement very shortly after eating indian food? it can't be getting through the gi tract that fast, right? | Many GI reactions are due to something simply being in the tract. When you eat some exotic food, your body may react to the unusual foods and spices regardless of where the food is in the digestive process. | [
"When infants bring solid foods to their own mouth, they are the ones guiding the sensory experience, starting and stopping when they are comfortable and ready. When food does move too posteriorly in the mouth triggering a gag reflex, the \"entire\" bolus is expelled from the mouth. Also, food moves slowly in compa... |
What forces /physical causes give a frisbee its lift, and why can't we manipulate them to create a flying saucer, similar to how we can utilize an airfoil to make a flying airplane? | The force that gives lift to a frisbee is the same aerodynamic lift utilized in a regular aerofoil ([Bernoulli's Principle](_URL_0_)). That lift force isn't balanced along the length of the disc and is generally larger at the front. Under normal circumstances this torque would cause unstable flight and the fisbee would flip. The spin that you put on the fisbee when you throw it stabilizes its flight through gyroscopic action (the faster the spin the more stable the fisbee). This unbalanced force is corrected in regular fixed wing aircraft via the tailplane.
So we could in theory create an plane using the frisbee concept but it would use so much energy to maintain stable flight that it would be inefficient.
| [
"Aerostats are so named because they use \"aerostatic\" lift, a buoyant force that does not require lateral movement through the surrounding air mass to effect a lifting force. By contrast, aerodynes primarily use aerodynamic lift, which requires the lateral movement of at least some part of the aircraft through th... |
motherboard types | It's basically just that each type of CPU needs a different motherboard, hence all the different kinds. Some boards also have different features, such as integrated graphics. | [
"Motherboards are produced in a variety of sizes and shape called computer form factor, some of which are specific to individual computer manufacturers. However, the motherboards used in IBM-compatible systems are designed to fit various case sizes. , most desktop computer motherboards use the ATX standard form fac... |
does epidural anaesthetic during childbirth inhibit uterine contractions | Epidurals for child birth generally are analgesic, not anesthetic.
An analgesic is something that blocks pain (at the doses typically used for labor it isn't always 100% effective at that, but it definitely knocks it WAY down in terms of severity). It still allows you to feel pressure (to know when to push) and allows you to have some level of muscle control. Anesthetics stop everything.
The common use of "Epidural anesthetic" is for a C-section. If a woman already has an epidural, but has to go in for surgery, then the anesthetist will use the epidural catheter to completely anesthetize the women from the mid-body down. | [
"Broadly speaking, surgical management of adenomyosis is split into two categories: uterine-sparing and non-uterine-sparing procedures. Uterine-sparing procedures are surgical operations that do not include surgical removal of the uterus. Some uterine-sparing procedures have the benefit of improving fertility or re... |
How does an electric motor turn electrical current into physical force | Get a magnet, a battery, and some wire. Put the magnet near the wire, then connect both ends of the wire to the ends of the battery. The wire should jump or move. This is because a current generates a magnetic field. If you coil the wire up, you multiply the magnetic field from the wire. You can put this coiled up wire (called a solenoid) next to a second wire connected to a battery and volla, you have some kind of engine. | [
"In this electric motor design, the force is produced by a linearly moving magnetic field acting on conductors in the field. Any conductor, be it a loop, a coil, or simply a piece of plate metal, that is placed in this field will have eddy currents induced in it thus creating an opposing magnetic field in accordanc... |
why do shoes/tires have better grip with less surface area touching the ground? | They don't. The greater the surface area in contact, the greater the friction (grip). Race cars have wide slick tires, rock climbing shoes have smooth soles. The problem is if it is wet then you get a layer of water between road and rubber so no contact and no grip. | [
"Off-road tires are typically radials with thick, deep tread. On dirt surfaces, the exposed edges of the tread dig into soft ground to give more traction than rolling friction alone, analogous to the traction provided by cleated shoes. These off-road tires provide their maximum grip on loose surfaces, but on paved ... |
Where would I find a cuneiform translation of a line from Gilgamesh? | _URL_0_
Clear sketches of the original tablets are way at the end | [
"To explain how divergent translations from the biblical text came about, Gregory Vall, a Christian professor of Religious Studies at Trinity Western University, speculated that the Septuagint translators were faced with כארו; i.e. as in the Masoretic text, but ending with the longer letter \"vav\" (ו) rather than ... |
Are there more even numbers or whole numbers? | You are asking about the [cardinality](_URL_1_) of a set and you have more or less stumbled upon how we define the size of sets. We say that the sets A and B have the same cardinality (written as |A| or |B|) if there is a bijective correspondence between the elements of A and B. This means there is a way to assign each element of A to a single, unique element of B, and vice versa.
So let's look at your example. Let A = {positive even whole numbers} = {2, 4, 6, 8, ...} and let B = {positive whole numbers} = {1, 2, 3, 4, 5, ...}. Consider the correspondence
> 2 < -- > 1
> 4 < -- > 2
> 6 < -- > 3
> 8 < -- > 4
> etc.
Note that this correspondence assigns each element of A to a unique element of B, and vice versa. We can write it succinctly as a function *f* from A to B, via the formula
> f(a) = a/2
So the sets A and B have the same cardinality, that is, they have the same size. There are just as many positive integers as there are even positive integers.
> But using this logic, why not take the more obvious approach? Let's say 2 corresponds to 2, 4 corresponds to 4. Then all of the even numbers have a partner (2 with 2 and so on), but not all of the whole numbers do. So there are more whole numbers?
This is a good question. You are now considering the map
> f(a) = a
Note that this map assigns each element of A to a unique element of B, but not the other way around. There are elements of B that do not have any corresponding element of A. This is perfectly fine. In fact, when such a map exists, we say that |A|≤|B|. That is, the size of A is *at most* the size of B. Why do we say only "at most"? Well, the map f(a) = a doesn't show that there is *no* map that assigns elements of B uniquely to elements of A. (In fact, we know such a map exists, it's just f(a) = a/2.)
So let's put everything together to make it all clear.
* If there is a one-to-one (not necessarily onto) map f: A- > B, then we say that |A|≤|B|, or that the size of A is at most the size of B.
* If there is a one-to-one (not necessarily onto) map g: B- > A, then we say that |B|≤|A|, or that the size of B is at most the size of A.
* If there is a bijective (one-to-one *and* onto) map h: A- > B, then we say that |A|=|B|, or that the size of A is equal to the size of B.
It turns out that [there is a theorem](_URL_0_) that states that if *f* and *g* exist, then *h* must also exist.
| [
"If a number is larger than another one, then the other is \"smaller than\" the first one. Examples: three is smaller than eight () and five is smaller than eight (). The symbol for \"smaller than\" is . A number cannot be at the same time larger and smaller than another number. Neither can a number be at the same ... |
How did ancient engineers (Roman or otherwise) determine elevation in order to build water projects? | The Romans had no good way to measure absolute elevation (i.e. height above sea level). They occasionally attempted to measure the height of mountains; but since they did not have barometers (or any concept of atmospheric pressure), they had to rely on [rather haphazard trigonometric methods](_URL_2_).
When it came to aqueducts, however, it was relative elevation that mattered - and this the Romans could determine fairly accurately. Once an aqueduct's source had been located, surveyors (often detached from the nearest convenient legion) began by tracing a route to the city. Typically, this route followed the contours of the land; the object was to keep the aqueduct channel subterranean, often following natural ridge lines, as long as possible.
To determine gradient (and thus elevation differences), Roman surveyors used two instruments: the chorobates and the dioptra. Vitruvius describes the chorobates in these terms:
“The chorobates is a rod about twenty feet in length, having two legs at its extremities of equal length and dimensions, and fastened to the ends of the rod at right angles with it; between the rod and the legs are cross pieces fastened with tenons, whereon vertical lines are correctly marked, through which correspondent plumb lines hang down from the rod. When the rod is set, these will coincide with the lines marked, and show that the instrument stands level. But if the wind obstructs the operation, and the lines are put in motion, so that one cannot judge by them, let a channel be cut on top of the rod five feet long, one inch wide, and half an inch high, and let water be poured into it; if the water touches each extremity of the channel equally, it is known to be level. When the chorobates is thus adjusted level, the declivity may be ascertained.” (8.5.1–2)
There is a handy illustration of a chorobates [here](_URL_1_).
A dioptra was used to measure the distance and height of features in the landscape. This was basically a primitive theodolite - to quote the description from the New Pauly article on the topic, a simple dioptra was "a ruler equipped with a builder's level and a metal tile with a viewing hole attached to one end (‘eye piece’). Another metal tile could be moved by the observer up and down a groove in the ruler. Focusing on the object to be measured through the viewing hole, the movable metal tile is pushed to the point where it obscures the observer's view of the object. After reading the measurement from the ruler and noting the measurement from the movable metal tile it was then possible to determine the angle or the apparent distance using Hipparchus' chord tables.” Since a dioptra was less unwieldy than a chorobates, this was likely the instrument used in the tunnels that made up most of an aqueduct's length.
An illustration of a (different kind of) [dioptra](_URL_0_).
With these and similar instruments, Roman surveyors could, albeit slowly and painstakingly, determine the elevation of a planned aqueduct’s sources and the slope of its channel. | [
"The construction of aqueducts was not an easy job. It was very difficult to make sure all the pipes were level and that the pressure was correct at both ends. The surveyor was responsible for calculating all these measurements beforehand and then leaving the directions with the procurator. They would most likely b... |
At high altitudes how does unconsciousness due to hypoxia occur in 10-15 seconds if you can hold your breath for up to 3 minutes? | Short answer: You can't hold your breath for 3 minutes at high altitudes.
At high altitudes, there's a lot less air. Air exerts a lot of pressure, it's just normally balanced by having a similar pressure inside and outside of your lungs so you don't notice. However, if you try to hold your breath with lungs full of high pressure air and an outside of low pressure air, there's a lot of force inside your lungs and not a lot from the outside. Funnily enough, none of the sources I found explicitly say that the air would be forced out of your lungs in this case, just that there'd be tissue damage if you tried to hold your breath. (None of them claim that you could successfully hold your breath either).
But fine, who needs air anyway? There's still oxygen in my blood. Not for long, though - normally, your lungs work because your blood has less oxygen than the air around it, and because gasses flow from high concentration to low, oxygen tends to enter your alveoli and thereafter your blood. However, once all the oxygen is gone from your lungs, the direction of the flow is reversed - instead of your lungs gaining oxygen from the air, they're losing it to the air, so even though you had a perfectly fine amount of oxygen, your body won't be able to use it before it's gone. | [
"In central sleep apnea, the basic neurological controls for breathing rate malfunction and fail to give the signal to inhale, causing the individual to miss one or more cycles of breathing. If the pause in breathing is long enough, the percentage of oxygen in the circulation will drop to a lower than normal level ... |
why do wood pigeons hoot in the same melodic pattern? | Many bird species have a very specific call that they all do. This is how they recognize fellow members of the same species at a distance | [
"The lightweight \"Pigeons\" is driven by a one-note banjolele line that parodies English musician George Formby. Steve Hackett commented in 2009 that \"the thing about ‘Pigeons’ was that it was possible for the band to play a whole note for a whole thing: ding-ding-ding-ding. And that was unvarying whilst the keyb... |
what is the process of a catholic confession, from walking through the church doors, to walking out afterwards? | when I was younger the confessionals were located in the back of my church. There was certain times that the priest held confession. The confessional was a booth separated by a screen you could do it anonymously or looking at the priest. I don't remember if he said my child.
So you go in and start the confession with bless me father for I have sinned, these are my sins. You list your sins and the priest will counsel you or say this is your penance ie say 10 hail Mary's etc. Also the priest is bound by an oath not to discuss your confession with anyone and he cannot be forced to tell anyone what you confessed not even by court order.
hope that helps | [
"In confession (also known as the sacrament of Penance or reconciliation), a person confesses their sins to a priest or bishop and receives God's forgiveness through absolution by the priest or bishop. This sacrament was criticised by many Protestants during the Reformation and abolished in many of the new Protesta... |
- how does someone get into whiskey/bourbons and able to pick up tastes? | Just like in beer, it takes training. You have to try a lot of different types and compare notes.
It helps to find one or two you really like, drink them a bit to become very familiar with them, then compare others to your "base". | [
"A food taster is a person who ingests food that was prepared for someone else, to confirm it is safe to eat. One who tests drink in this way is known as a cupbearer. The person to whom the food is to be served is usually an important person, such as a monarch or somebody under threat of assassination or harm.\n",
... |
why was half life 2 considered such a milestone in gaming? | It had amazing graphics and physics at the time, just compare [it's character animations](_URL_2_) with a similar game at the time like [Far Cry](_URL_0_) and you can see it still holds up, and is even better than some [current games](_URL_1_).
Not to mention it's just a really good game to boot. | [
"\"Half-Life\" sparked numerous fan-made mods, several of them becoming standalone games, notably \"Counter-Strike\", \"Day of Defeat\" and \"Sven Co-op\". A sequel, \"Half-Life 2\", was released in 2004. An unofficial remake of \"Half-Life\" titled \"Black Mesa\" was released in 2012 as a mod of \"Half-Life 2\".\n... |
can hard liquors ever go bad? | Hard liquor such as vodka have near limitless shelf lives when unopened, however, once the seal is broken and the liquor has been exposed to the air it will only last around 6-8 months | [
"The production of hard liquor has a tradition dating back to the 18th century and was at a high in the 1840s. Since the 1880s, the state-owned Systembolaget has a monopoly on selling spirits with more than 3.5% ABV, limiting access. \"Hembränt\" (moonshine) used to be made in rural Sweden, but production has lesse... |
How does Mithras fit into Zoroastrianism? | Sorry for the briefness and oversimplification...I browse this forum too late at night...but here goes:
A yazata is anything to be worshiped in Zoroastrianism. Ahura Mazda is the highest yazata. The divine sparks are all manifestations of different qualities of Ahura Mazda, and they are yazata as well. Much like the Catholics today pray to saints, the Zoroastrians could pray to various yazata. One of the most popular was Mithra, the protector of oaths, cattle and the sun. Mithra later became a popular deity in the Roman army.
So, long story short - the Persians would see him as an angel or saint, the Romans would see him as a full god. | [
"Mithra was worshipped throughout the Roman era, from the late Republic to the later Imperial era. The cult of Mithraism spread from the Middle East to other parts of the Roman Empire throughout the Mediterranean basin, at first by military-political adventurers, travelers, slaves and merchants from the Orient. Lat... |
How was China able to stay so technologically advanced compared with the rest of the world throughout most of its history despite having little contact with other civilizations? | Firstly, China engaged in much more trade than you're suggesting. The silk road, running from central China through Central Asia and the Middle East to Europe was the longest trade route throughout much of human history - there was plenty of technological exchange, such as the spread of gunpowder to Europe. China was much less isolated than is often believed, and has never cut off trade with the outside world like Japan did.
Now, why did so many important inventions occur in China? Likely for the sole reason that it was a large area with a sufficiently developed economy to support artisans and inventors. One significant factor here was likely the lack of feudalism - Chinese peasants were not serfs, and could buy and sell land as early as the 10th century AD. This allowed those with the means to do so to specialise in particular crafts - consequently, China may well have had a proportionally larger pool of "skilled labour" in the medieval period.
| [
"In 1980, the Chinese computing technology was estimated to be about 15 years behind United States technology. From the early 1980s on, China’s leaders recognized that their nationalistic development strategy was inhibiting their scientific competitiveness with the West. Therefore, imports from the United States an... |
what is piezo-electricity and what are its uses ?? | Piezoelectricity is an effect found in some solid materials that causes a charge to build up when it's under stress (an applied force). This relationship makes possible to use electricity to cause deformation of the material, known as the *converse piezoelectric effect*. This basically means you can create movement just by applying an electric field, which is very useful in the manufacturing industry.
On of the key uses is in 3D printing, specially the drop-on-demand binder and material jetting processes. These work by selectively forcing small droplets of material in place and moving over the surface. Using a piezoelectric actuator means that an electric current can be used to accurately and rapidly deposit these droplets. It also means that a thermal actuator doesn't need to be used, avoid problems with thermal cycling and burning of the material. | [
"A piezoelectric nanogenerator is an energy harvesting device capable of converting external kinetic energy into electrical energy via action by a nano-structured piezoelectric material. Although its definition may include any types of energy harvesting devices using nano-structures to convert various types of ambi... |
What is the physical volume of a visible rainbow? | _URL_0_
A rainbow is a refractory effect. You're seeing light refracted from a collection of water droplets that happen to be in the correct position relative to you and the sun for you to see it. Someone standing in a different location seeing the 'same rainbow' is seeing it refracted from a different section of a larger collection of water droplets. | [
"From above the earth such as in an aeroplane, it is sometimes possible to see a rainbow as a full circle. This phenomenon can be confused with the glory phenomenon, but a glory is usually much smaller, covering only 5–20°.\n",
"St. Albert the Great was the first to propose that each drop of falling rain had the ... |
what is a css subreddit? | CSS is cascading style sheets. Basically it enables admins of specific subreddits to create a look and potentially change some functionality (like removing downvote buttons) to help enforce the feel of the sub. | [
"CSS-in-JS is a styling technique where JavaScript is used to style components. When this JavaScript is parsed, CSS is generated (usually as a style element) and attached into the DOM. It allows you to abstract CSS to the component level itself, using JavaScript to describe styles in a declarative and maintainable ... |
Can an α-particle ejected from a radioactive nucleus capture 2 of the nucleus's electrons and become a helium atom? | Captured from the atom that is undergoing the radioactive decay? I would say - impossible.
Imagine a marathon runner trying to get two drinks at the same time from a water station. Except that instead of running, he is driving an Indycar while blindfolded.
I am guessing it is something like that. | [
"The electron that is captured is one of the atom's own electrons, and not a new, incoming electron, as might be suggested by the way the above reactions are written. Radioactive isotopes that decay by pure electron capture can be inhibited from radioactive decay if they are fully ionized (\"stripped\" is sometimes... |
in what way is the unionization of european states similar than or different from the unionization of early states and territories of the us? | Different. They're not forming a federal government with explicit foreign affairs and military "supremacy" over the individual states. That is, local militaries are not being disbanded, and individual nations within the EU can maintain varying degrees of foreign relations with external countries, independent of the EU's "stance." | [
"Legitimation of the European Union rests on the Treaty System. The move toward unification first arose in the Kellogg-Briand Pact in 1928, which gained adherent countries during negotiations and took on a theme of integration for the achievement of peace between the Great Powers. After World War Two, Europe sought... |
Can someone explain the new prenatal DNA tests to me? | you mean paternity tests? or chromosomal screening?
The [American Pregnancy Association](_URL_1_) can answer your questions, or the [Prenatal Genetics Center](_URL_0_)
Or maybe you're referring to the new [non-invasive screening process](_URL_2_), it actually reduces the risk of miscarriage (which is less than 1% for the procedures) | [
"Genetic testing for a variety of disorders has seen many advances starting with cytogenetics to evaluate human chromosomes for aneuploidy and other chromosome abnormalities. The development of molecular cytogenetics involving techniques such as fluorescence in situ hybridization (FISH) followed, permitting the det... |
How do you view old scholarly secondary sources? Should their conclusions be discounted because newer sources on the same issue exist? | In general, a good rule of thumb is that the newer the source is, the more likely it is to reflect the current state of research on the subject. Obviously, you have to read every article or book critically and evaluate their argument, no matter the age (because even now people write just as much bad scholarship as good scholarship). However, it is often important to read older works to understand the development of certain ideas. It is always best to read the original paper or book which expressed an idea or quote that is cited in a later paper. You never know if a scholar might accidentally use it out of context or misspell something by accident (slip of the fingers and all that). For that reason, I have read a lot of works ranging quite far in age.
In my subfield especially (archaeology), we work a lot excavated material. Because we don't always get to look at the excavated material itself, or get to visit the site or see the material being excavated, we have to read the reports of the excavation which are published by the original excavators. This gives us an overview and explanation of the context of the material which we are studying. For an explanation of why context is important, check [out this Monday Methods essay from a couple weeks ago](_URL_0_).
Some of these excavation reports (or "site reports" as they are sometime called) are from excavations conducted some time ago. Many important excavations were conducted in the 1960s and 1970s, and even earlier in the 1920s and 1930s. For one paper I had to write, I had to consult a 1912 document by George Reisner outlining the discovery of the Samaria Ostraca, as it was the main record outlining the locations and descriptions of the finding of the ostraca. I've had to consult many excavation reports, from a wide swath of time. Of course, at the same time, you have to consult modern works, which all consult the same older works, It's a mountain shaped like an upside-down triangle, of works referring to older works referring to older works. Obviously, you often deal with people reviewing older works and finding their conclusions to be in error, based on more recent scholarship or excavation. That's part of the academic endeavor. We're always trying to reevaluate what has been learned and reinterpret it in the light of new information and ideas. So it's really a mix of old and new ideas constantly being reevaluated. Sometimes, old sources provide a lot of important information, but their conclusions are faulty because new information has since been discovered. But it's still worth reading the old ones, so we can maintain the link of constant correction.
If you want to see what an excavation report looks like, you can download copies from the site at which I work, which are provided for free under the Creative Commons license:
_URL_1_ | [
"Many sources can be considered either primary or secondary, depending on the context in which they are examined. Moreover, the distinction between \"primary\" and \"secondary\" sources is subjective and contextual, so that precise definitions are difficult to make. A book review, when it contains the opinion of th... |
why are salty and fatty foods the tastiest things to eat when your drunk. | They're always the tastiest, but when you're drunk the voice in your head that would usually say "no that's bad for you" just says HUNGRY | [
"Most soft drinks contain high concentrations of simple carbohydrates: glucose, fructose, sucrose and other simple sugars. If oral bacteria ferment carbohydrates and produce acids that may dissolve tooth enamel and induce dental decay, then sweetened drinks may increase the risk of dental caries. The risk would be ... |
How do forensics deal with identical twins? | Identical twins have identical DNA that cannot be distinguished from each other.
They do have different fingerprints, though. | [
"Criminal anthropology, and the closely related study of Physiognomy, have also found their way into studies of social psychology and forensic psychology. Studies into the nature of twins also combines aspects of criminal anthropology, as some studies reveal that identical twins share a likelihood of criminal activ... |
When did the U.S. turn away from having a major religious presence in the government during the 20th century? | I'm not certain on this answer at all, but I'm willing to bet it died, quickly, with Kennedy. His religion was a very touchy subject, so it would have been prudent of him and his administration to downplay religion.
It's also worth noting that religion became a more important part of America's politics in direct response to "godless" communism. There's really not *that* much precedent for religion in US politics. | [
"During the sovereignty of the United States, the American government implemented the separation of church and state. It reduced the significant political power exerted by the Church, which led to the establishment of other faiths (particularly Protestantism) within the country. In this era, in the first decade of ... |
why are some words considered more offensive/rude than others, despite meaning a very similar or even the exact same thing? i'm referring to swear words mainly. | Similar question has been asked more than once today. It's weird.
All languages have curse or swear words; words used to describe acts, ideas, or concepts that are considered taboo by the culture that uses said language. These can vary widely from culture to culture, of course, but the common taboos in western civilization are (as I'm sure you're aware) sex-related.
In English, at least, the idea of "poor" or "bad" language also comes in part from how the language as we know it today developed during the middle ages. In the simplest terms, the common people spoke a different dialect than the Norman French nobility, and the so-called "vulgar" (literally "common" in Latin) vernacular was seen as dirty, impure, and distasteful to the prim and proper Norman overlords. | [
"Profanity is socially offensive language, which may also be called curse words or swearing (British English), cuss words (American English and Canada), swear words, bad words, crude language, coarse language, oaths, blasphemous language, vulgar language, lewd language, choice words, or expletives. \n",
"The word... |
When did the idea of secession from the United States become almost unthinkable? When did people start thinking of the US as an unbreakable collection of regions subject to a federal government? | As a practical matter, the Civil War decided the issue, however, the Supreme Court officially ruled on the issue in Texas v. White in 1868. | [
"Discussion about the right of U.S. states to secede from the union began shortly after the American Revolutionary War. The United States Constitution does not address secession. Each of the colonies originated by separate grants from the British Crown and had evolved relatively distinct political and cultural inst... |
why is it that i wake up right before the good parts | I remember reading that the "good" part gets you excited and that excitement is what may contribute to you waking up. | [
"[...]And while you sleep you don’t know what happens either, what could have been changed while you have been sleeping. If things are different when you woke up just now, it could have been different before and you might not have remembered. Or if it is the same, the scenery, one way or the other you don’t see muc... |
If time is dependent on speed, what is the reference point? | There isn't any special reference point that matters. Your results simply depend on whichever reference frame you happen to find most convenient. | [
"It is important to note some assumptions made above about the various inertial frames of reference. Newton, for instance, employed universal time, as explained by the following example. Suppose that you own two clocks, which both tick at exactly the same rate. You synchronize them so that they both display exactly... |
why do patents expire? | So that a patented device or technique or medicine cannot remain proprietary forever. This is important because it would then allow for people to later build upon whatever was previously patented to continue advancement in creative, industrial and scientific endeavors.
The idea of patents (and copyrights, even though those are different) are to allow a creator or inventor to make a profit on their work by being the only one who has rights to it for a period of time. However, in order for things to move forward, eventually such exclusivity must expire.
It's also a reason why certain companies do not patent their creations, and instead opt to keep them as trade secrets. Which never expire, but do not carry all of the same legal protections. | [
"Excessive patent protection may also be attributed to evergreening, or methods to extend patents that are about to expire. Drug companies may extend patents well beyond their original expiration date by making slight modifications to their drug, preventing antiretroviral drugs from attaining reduced prices. For ex... |
how did internet explorer and chrome end up so different? | Internet Explorer has a lot more history than Chrome has.
In the mid-late 90's, Microsoft had managed to tie in business deals with a lot of PC manufacturers, governments, schools, and so on to make Windows the default operating system on something like 95% of the personal computers in the world. Internet Explorer came bundled with Windows, so it was the default browser for 95% of people. What happens when you control that much of the market is you basically control what standards are set.
So for a while Internet Explorer was the best browser around, because it supported the standard best. In fact, it pretty much *was* the standard.
Then the world moved on. Microsoft, being the absolutely massive corporation that it is, has some inertia. It took them a while to notice that other browsers (most notably Mozilla, later known as Firefox) were helping the W3C (World Wide Web Consortium, the guys who actually decide how the web should work) to move the web in a new direction, implementing better standards and more sane defaults.
Before Microsoft could react, IE was way behind in terms of features (due in part to them continuing to set their own standards as if the other browsers didn't exist for a few years).
Since about 2002, IE has been playing catch-up with other browsers. Now Google enters the market.
Armed with the knowledge of what went wrong for Microsoft, they decided (at first) against building their own browser engine, instead opting to modify the KDE project's Webkit engine (the one that powers Safari). The reason for this is that Webkit is open-source and therefore can be worked on by a lot of people from different backgrounds at the same time, which prevents stagnation. Since Apple had jumped on it for Safari, it also meant that it already had the support of a large company.
That's basically it, if you leave out the technical details (like Chrome being built to be multicore from the ground up while some of the codebase in IE was over a decade old at some points).
However, you feeling that IE is awkward right now is probably just a social thing. IE has a *really* bad rap for all the things it did wrong in the mid-00's, but the latest incarnation of the browser (version 11) is a very snappy little thing that uses barely any memory and has argually the best touch-screen support out of any browser in the market.
**Edit:**
Also, the IE team are still cool guys that send cakes to the other browser devs when they hit a major release.
Or, well, they used to. Since Mozilla started with their 6-month release schedule for Firefox, they only get muffins. Serves them right for trying to cheat the system :P | [
", StatCounter estimates that Chrome has a 71% worldwide browser market share on traditional PCs and 63.34% share across all platforms. Because of this success, Google has expanded the \"Chrome\" brand name to other products: Chrome OS, Chromecast, Chromebook, Chromebit, Chromebox, and Chromebase.\n",
"Google Chr... |
What if Venus turned out to be more like Earth?
| > Also, consider that intelligent life arose on Venus around the same time as humans on Earth, at what point would we both be detectable to each other?
Probably a little after we both developed radio. If not the first probes sent to Venus would have probably have found them.
> How would his affected the scientific and technological development timelines?
Almost impossible to say. I depends how technologically advance they were. How large their population is. And probably several other factors.
> Would there be an explosion in science in the discovery of such a near by intelligent neighbor?
We would probably be more interested in going to other planets. And, if the conditions were right we could collaborate on our science and share the load. This should make progress go quicker.
Fun fact: Venus has the most earth like habitat in the solar system (besides earth of course). At about 50km into the atmosphere it has a pressure of about 1 atm, a temperature of about 0-50 C, and a little under 1g of gravity. | [
"In the early 20th century, Venus was often thought to be similar to Earth in terms of habitability, but observations since the beginning of the Space Age have revealed that Venus's surface is inhospitable to Earth-like life. However, between an altitude of 50 and 65 kilometers, the pressure and temperature are Ear... |
why do you need to apply pressure to bullet wounds? | pressure slows the bleeding and helps promote clotting.
Either that or they are afraid the bullet will shoot back out of the wound and kill someone else. | [
"Placing pressure on the wound constricts the blood vessels manually, helping to stem blood flow. When applying pressure, the type and direction of the wound may have an effect, for instance, a cut lengthways on the hand would be opened up by closing the hand into a fist, whilst a cut across the hand would be seale... |
how were large purchases made in gold coins during the middle ages? i.e. 2 million gold pieces? | People didn't really buy anything worth that much.
Considering how much gold has historically been worth, a couple of coins could buy most commodities, and even a good-sized castle (if you could even buy a used castle) wouldn't be worth more than a few dozen large chests of gold. | [
"For all that the surviving western specimens of early medieval gold coins must represent only a tiny proportion of the original stock, it must be borne in mind that before the 13th century gold coins were extremely rare in western Europe: in England, for instance, only eight native gold pieces with meaningful lege... |
what exactly happens when you see a beam of light? | The space between the light source, and whatever it is being shone upon is not empty. In fact, it's got lots and lots of stuff bouncing around in it. Light is hitting those things and bouncing off them in not-quite-random directions. Dust motes, smoke, water vapor, etc. Your eyes are picking up photons pinged off a microscopic flake of cotton from someone's t-shirt who walked by a month ago. | [
"From the side, a beam of light is only visible if part of the light is scattered by objects: tiny particles like dust, water droplets (mist, fog, rain), hail, snow, or smoke, or larger objects such as birds. If there are many objects in the light path, then it appears as a continuous beam, but if there are only a ... |
why isn't the board game go as popular or mainstream around the world as.chess? | There are many cultural factors at play here. The places where Go is popular (China, Korea, & Japan) had a lot of cultural exchange over the last millennium. The places where chess is popular (Europe, US, Arabia) also had a lot of cultural exchange over the last millennium.
I have heard that Go is representative of eastern thinking. It favors a subtle, amorphous, indirect approach. All the pieces are equal, and any piece can be placed anywhere on the board at any time. You can't 'see' the opponents 'army' until they use them. In chess, the armies march directly at each other, every piece is visible on the board from the beginning, and some pieces are definitely more important than others. | [
"Chess is a two-player strategy board game played on a checkered board with 64 squares arranged in an 8×8 grid. The game is played by millions of people worldwide. Chess is believed to be derived from the Indian game chaturanga sometime before the 7th century. Chaturanga is also the likely ancestor of the Eastern s... |
when muslims want sharia, what does that mean? does it mean that everyone, even non muslims should abide by those rules as well? | Yes, that's what it means.
Christians and Jews are specifically given the right to pay a tax, so long as they demonstrate that they are subservient to Islamic authorities, and are exempt from some of the prohibitions imposed on Muslims, but those exemptions are mostly religious proscriptions. The Christians and Jews paying the tax would still be required to follow the civil and criminal code (so for example, Christian or Jewish law would apply to matters of dealing with the estate of a dead person or determining who could marry whom, but Christian and Jewish women would still have to conform to the required 'modesty' regulations for dress.)
Non-muslim people who are neither Christian nor Jewish or who don't pay the tax are outside the limits on the law and the Muslims can pretty much do anything they wish, including enslaving them. | [
"Muslims believe \"sharia\" is God's law, but they differ as to what exactly it entails. Modernists, traditionalists and fundamentalists all hold different views of sharia, as do adherents to different schools of Islamic thought and scholarship. Different countries, societies and cultures have varying interpretatio... |
why doesn't earth spiral closer and closer to the sun due to the sun's gravity? | Because the Earth has enough velocity (that is, kinetic energy) to keep from falling into the sun.
**WARNING: BUCKET ON A STRING ANALOGY APPROACHETH**
So you've got your bucket on a string, swinging around you. Gravity wants to pull it towards the Earth, but it's literally standing straight out from you, perpendicular to where it should be. That's because the rotational energy of the bucket is such that it counteracts the attraction of the Earth, in fact it completely cancels it.
The 'energy' of the Earth's orbit is the same concept - the Earth has enough kinetic energy that it doesn't fall (that's the energy of our orbit around the sun, the 'speed' that makes the year 365 days long). If we were to suddenly stop, we would 'sink like a stone' plunging straight toward the center of the Earth-sun system. | [
"The Earth, among other planets, orbits the Sun because the Sun exerts a gravitational pull that acts as a centripetal force, holding the Earth to it, which would otherwise go shooting off into space. If the Sun's pull is considered an action, then Earth simultaneously exerts a reaction as a gravitational pull on t... |
why are humans not tired anymore shortly after contact with water on their bodies, for example in the shower after waking up in the morning or splashing water in their faces? | It's an instinct thing. Our body's associate water on our face with one of two immediate hazards. One rain and foul weather. And two being in a large body of water and being at risk of drowning. Our body places priority on not dying and thus we are kept alert | [
"Besides, those with cold and wet \"Mizaj\" should not sleep much as long sleep would increase wetness in the body. People with phlegmatic temperament should cut down on food items cold and wet temperament to sleep shorter and get up easily and not having trouble waking up. They had better wake up once or twice dur... |
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