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Is there any footage of a Lunar eclipse when viewed from the moon? | [Just a pretty drawing](_URL_0_) | [
"Terrestrial solar eclipses, on the other hand, would not be as spectacular for lunar observers because the Moon's umbra nearly tapers out at the Earth's surface. A blurry dark patch would be barely visible. The effect would be comparable to the shadow of a golf ball cast by sunlight on an object away. Lunar observ... |
what is the difference between "high mileage" oil, versus "regular" oil, for cars? | Mostly the only difference is "high mileage" oils generally contain some products that are supposed to help recondition the seals inside the engine. If your car isn't leaking or burning oil though your engine seals are doing their job just fine and it probably isn't worth the extra money. | [
"Most motor oils are made from a heavier, thicker petroleum hydrocarbon base stock derived from crude oil, with additives to improve certain properties. The bulk of a typical motor oil consists of hydrocarbons with between 18 and 34 carbon atoms per molecule. One of the most important properties of motor oil in mai... |
why do some sports favour the very young and people are considered 'past it' in their 20s, while in other sports people can remain competitive into their 50s or even 60s? | It really depends on the sport. An equestrian that's 50 can probably ride a horse pretty well still, because most of the "skill" there is knowing how to handle the horse, not the physical strain of doing it.
Gymnastics, on the other hand, demand performance near the limits of human capability, and greatly favor young... | [
"Sport can greatly contribute to the physical, social and intellectual development of youngsters.Sport is a prevailing tool for the promotion of mutual understanding, peace and tolerance. The power of sport can break down cultural, religious and ideological barriers, no matter how big.\n",
"Youth sport refers to ... |
What would daily life have been like as an average person in the Aztec civilisation? | I would recommend reading Daily Life of the Aztecs by Jacques Soustelle | [
"Aztec society combined a relatively simple agrarian rural tradition with the development of a truly urbanized society with a complex system of institutions, specializations and hierarchies. The urban tradition in Mesoamerica was developed during the classic period with major urban centers such as Teotihuacan with ... |
how are abstract expression arts expressive? and what separates artworks like starry night from its contemporaries? | So abstract means that the artist doesn’t have to stay within real world logic. Instead of showing a scene as it exists from a real perspective, they are free to change the shape or color or anything they want. Sometimes the change is small, but it can also be changed so much that it looks nothing like reality.
Abs... | [
"The technique of his poetic work has always been compared with that of surrealism, although is, in fact, different because \"the accumulation of images, apparently disconnected, comes from the will (...) to express chaos as it is lived. There is, therefore, no work on the \"free associations\", but conscious disag... |
Were Western adventurers to Indian surprised to find people recognisably practising Christianity? | The Portuguese who first arrived in India were unfamiliar with Hinduism, and initially thought that it was a strange but vaguely recognizable form of Christianity, and rested some hopes on an alliance with the local "Christians" against the Muslim traders. Proposed reasons for this include the existing legend of the ki... | [
"A minor objective included the delivery of a group of Franciscan missionaries to India. It is said that Vasco da Gama had misinterpreted the Hinduism he saw practiced in India as a form of 'primitive' Christianity. He believed its peculiar characteristics were a result of centuries of separation from the mainstrea... |
If a baby would grow up in a cage without ever seeing humans or other animals would it eventually start to walk like a human? | People born blind can walk. Or did you mean something more like "would an individual raised in isolation learn to walk on their own?" | [
"From the moment children could walk, they were expected to fend for themselves. Aside from feeding, children were taught to act individually early on. Once a child was around one or two years old, they were carried around on the mother's back. Early in the child's life, mothers will, despite the well known risk of... |
how come you can buy almost every drink in bottles and cans except water which can only seem to be bought in bottles? | Water isn't highly pressurised like sodas therefore there is no real need to put it in a can. With a bottle you can replace the lid and store the water in your bag. I think the biggest thing would be that people don't tend to see water as a treat like they do with sweet drinks, therefore you don't want to have to dri... | [
"Polyethylene terephthalate (PET) bottles, which have the number 1 and/or PETE with the recycling symbol on the bottle are no longer allowed to be sold if they are less than or equal to 1 liter (34 ounces) and contain water which is non-sparkling and non-flavored. The sale of water in bottles made of other types of... |
The Soviet Union said it was a revolutionary state in the way to communism, not already in a state in communism. What steps had they taken during their existence to advance the revolution to more communism? | There is an assumption that the leaders of the Soviet Union were not true believers of Communism. That their "luxurious" lifestyle somehow proved that their belief was inequality or they lived the same bourgeois lifestyle of the Tsar's before. Stephen Kotkin dismisses this idea regarding Joseph Stalin and the others in... | [
"This analysis is consistent with Lenin's April Theses, which stated that the goal of the Bolshevik revolution was \"not\" the introduction of socialism, which could only be established on a worldwide scale, but was intended to bring production and the state under the control of the Soviets of Workers' Deputies. Fu... |
how does smelting work? | The metal atoms have a chemical bond with other atoms, usually oxygen. One type of iron ore for example has the chemical structure Fe2O3, two iron bond with three oxygen atoms. While you can heat up the metal so much that this bond can be broken, this is of no use, since you need to physically separate the atoms in ord... | [
"Smelting is a process of applying heat to ore in order to extract a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other e... |
What celestial bodies are most common in the universe? | There are more planets than stars. The number of rogue planets in our galaxy is about the same as the number of stars, as far as we can tell from microlensing surveys, and most stars appear to have a planetary system.
It's hard to say which types of planets are most common. Our ability to detect exoplanets is limited,... | [
"Based on observations from the \"Hubble Space Telescope\", there are between 125 and 250 billion galaxies in the observable universe. It is estimated that at least ten percent of all Sun-like stars have a system of planets, i.e. there are stars with planets orbiting them in the observable universe. Even if it is a... |
After the WW2, how did the allies made sure that Nazi sympathizers wouldn't use the Democratic system to gain influential positions in the government? | After World War II the occupying forces in Germany started a program of "Denazification." The idea was to basically go over anyone who had any significant role in Germany during the Nazi period and have a tribunal of sorts about the extent of their "Nazi-ness." Obviously this was a tricky sort of thing to suss out at t... | [
"In 1945, the occupying Allied Powers began their own programme of de-Nazification. It was understood that, in a totalitarian state, few people could participate in public service without also being members of the Nazi Party. Party membership alone was not viewed as sufficient grounds for dismissal, but allegations... |
what is the difference between the president and premier in china? | Premier is their prime minister, the head of the Chinese legislature.
However, since the legislature has very little power in China, the president is the one who really has control. | [
"The President is the titular head of state, elected by the National People's Congress. The Premier is the head of government, presiding over the State Council composed of four vice premiers and the heads of ministries and commissions. The incumbent president is Xi Jinping, who is also the General Secretary of the ... |
why do scars sometimes hurt after they heal? | The skin has healed but the nerve endings don’t necessarily heal at the same rate as skin. Nerves can take up to years to heal. | [
"When a normal wound heals, the body produces new collagen fibres at a rate which balances the breakdown of old collagen. Hypertrophic scars are red and thick and may be itchy or painful. They do not extend beyond the boundary of the original wound, but may continue to thicken for up to six months. They usually imp... |
Is there any way we use / can use magma? | *Layman speculation*: Just thinking out loud here, but suppose we were to pipe magma through some magical pipe that could withstand the heat, and we were to use it to heat something, say water for power generation. If the magma is heating water, then it is cooling. And if it is cooling, wouldn't it begin to clog the pi... | [
"The Magma system is used extensively within pure mathematics. The Computational Algebra Group maintain a list of publications that cite Magma, and as of 2010 there are about 2600 citations, mostly in pure mathematics, but also including papers from areas as diverse as economics and geophysics.\n",
"If the magma ... |
how would dropping thermonuclear bombs at mars' poles make the planet more habitable? | Beneath the surface of the mars there is a lots of carbon dioxide. By heating and stirring the planet a bit you release the carbon dioxide from the soil, that creates a green house effect. Which heates the planet more, which releases more carbon dioxide, rince and repeat.
In a relatively short time you get a planet wh... | [
"According to scientists, Mars exists on the outer edge of the habitable zone, a region of the Solar System where liquid water on the surface may be supported if concentrated greenhouse gases could increase the atmospheric pressure. The lack of both a magnetic field and geologic activity on Mars may be a result of ... |
the difference between a course offered at a university vs a course offered at a community college. | Honestly? Not much. It's just that once you hit classes above a "sophomore" level, you need to go to a university. The lower level classes are pretty much the same though, and by pretty much I mean the variation between a university and a CC is about the same variance that you would get from professor to professor anyw... | [
"Community colleges are often two-year colleges. They have open admissions, usually with lower tuition fees than other state or private schools. Graduates receive an associate's degree, such as an Associate of Arts (A.A.), upon graduating. Many students earn an AA at a two-year institution before transferring to a ... |
when is object oriented design called for? | The thing that made it "click" for me was when I first started looking at the Java GUI API.
I haven't used Java for many years now, but I regularly use C# with Windows Forms, which has many similar features in the way the GUI is implemented.
I saw that Button, TextBox, ListBox and many others all inherit from somethi... | [
"Object-oriented analysis and design (OOAD) is a popular technical approach for analyzing and designing an application, system, or business by applying object-oriented programming, as well as using visual modeling throughout the development life cycles to foster better stakeholder communication and product quality.... |
Why can't dead organism be revived if their organs are intact? | What OP is asking is if we can use the heart after a few hours, why can't we just restart Uncle Joe or my ferret Bobbert. To vastly oversimply things, cells vary tremendously in how tolerant they are to the sort of oxygen deprivation you see when the lungs and heart stop working. The bits that make all the other bits... | [
"The regrowth of lost tissues or organs in the human body is being researched. Some tissues such as skin regrow quite readily; others have been thought to have little or no capacity for regeneration, but ongoing research suggests that there is some hope for a variety of tissues and organs. Human organs that have be... |
how much raw data speed can we realistically transmit on a single optical fiber? | For a single wavelength the limit is related to how fast you can switch the laser on/off OR how fast you can modulate a continuous laser with a shutter. The frequency of the light is around 200THz. The amount of data you can get through a fiber is also limited by the signal to noise ratio of the system. A cleaner, stro... | [
"BULLET::::- Japanese researchers achieve a new world record for data transmission, demonstrating one-petabit-per-second fiber transmission over : equivalent to sending 5,000 HDTV videos per second over a single fiber. (NTT)\n",
"At 10 MHz with a bus width of 16 bits it is possible to achieve a data rate of 20 MB... |
Do serial killers suffer from an addiction the same way that alcoholics suffer from an addiction? Are there people that are more prone to serial killing after a single kill? | Yes! A neuroscientist named Fallon did CT scans of convicted killers, including members of his own family, and found that they had less brain activity in the orbital cortex, which is typically caused by trauma or genetics. The orbital cortex helps control aspects of the amygdala which harbors our instincts of aggressio... | [
"BULLET::::- Morrison states that \"no serial murderers are addicted to drugs, drink, or even smoking.\" There are multiple known instances of serial killers using drugs or alcohol. John Wayne Gacy was known to smoke marijuana, and Jeffrey Dahmer was alcoholic.\n",
"Most people are under the influence of sedative... |
why do sites like youtube run like crap on my laptop but run great on my tablets? | Perhaps your laptop needs a RAM or processor upgrade. Perhaps you are running too many processes/programs simultaneously. Perhaps your laptop, which I'm assuming is older than your tablet, has accumulated some malware/spyware. Perhaps you need to update your flash or shockwave player. Perhaps you need to update your br... | [
"There have been exploits where web pages grab clipboard data. In early 2013 researchers exposed risks stemming from Android-based password managers and documented how passwords in 21 of the most popular of these apps could be accessed by any other app on an Android device including those with extremely low-level p... |
Why why were ministries of war renamed ministries of defence? | Because I was curious and so others have some examples (mods, please feel free to remove if this is unhelpful or inaccurate), I've made a few very simple timelines below:
**United States** (source: _URL_2_)
*1789-1947*: War Department/Department of War/War Office
*1947*: Split into Dept. of the Army and Dept. of th... | [
"Historically, such departments were referred to as a Ministry of War or Department of War, although such departments generally had authority only over the army of a country, with a separate department governing other military branches. Prior to World War II, most \"Ministries of War\" were Army ministries, while t... |
How did the transition from wooden ships to ironclads go? Did the French/Royal Navy train new crews, or just retrain old crews? What would have been different?" | The transition from wooden ships to ironclads took a fair amount of time, and the major difference came not from the advent of armor per se, but the new methods of propulsion.
Many ships used both steam and sail for a period of time (I wrote an [answer on this](_URL_0_) awhile back), so the new training that people n... | [
"From 1816 to the 1830s, the Navy accumulated extensive stocks of live oak timbers for use in new warship construction under the provisions of the Act for the Gradual Increase of the Navy of the United States, passed in 1816. In the early 1850s, the Navy decided to build a new sail-powered ship using these existing... |
can doctors diagnose themselves? if not then are they allowed to be diagnosed by doctors from the same clinic/hospital? | It's not recommended, especially the self-prescribing part, and some states do have rules against prescribing for somebody that isn't actually your patient, but generally they're free to do what they want. Most wouldn't self-diagnose anything serious due to the loss of objectivity. It can introduce a lot of bias and th... | [
"In the United States, physicians may hold either the Doctor of Medicine degree (MD) or the Doctor of Osteopathic Medicine degree (DO). MD and DO physicians complete similar residency programs in hospitals, can be licensed in all 50 states, and have rights and responsibilities common to physicians.\n",
"Doctors a... |
how do drug dealers make profit when they are buying drugs from another drug dealer who most likely bought drugs from another dealer? | The same is true of literally any product in the world. For example, when you buy groceries, you don't buy from farmers do you? You buy from a store, that buys from a distributor, that buys from farmers. The farmer sells in bulk to the distributor who sells in less bulk to the store who sells in single units to you. Th... | [
"The player may also deal drugs amongst other suppliers, both buying and selling. Drugs can be bought at one point and kept for several days, in which they may increase in value, thus making a profit for the player. Additionally, varying drugs can be obtained throughout each of the levels, and sold for a profit onc... |
What keeps the flora in the gut from leaving the gut and infecting the rest of the body? | Bacteria are much larger than the route taken by the water and nutrients removed from the gut. The epithelium lining the gut is covered with mucus and the epithelial cells are bound together with special tight junctions that keep the two environments separate. Isolation is so important that gut epithelium replaces itse... | [
"The gut flora community plays a direct role in defending against pathogens by fully colonizing the space, making use of all available nutrients, and by secreting compounds that kill or inhibit unwelcome organisms that would compete for nutrients with it. Disruption of the gut flora allows competing organisms like ... |
in america, why do black and white people speak so differently despite being born and raised in the same city? | Living in the same place doesn't always mean having the same social environment, and it's the latter where people get their speaking habits. In many American cities, black and white people tend to have different family backgrounds, live in different neighborhoods, go to different schools and have different jobs. | [
"In America, Black and White differences are the most significant groupings largely because of American history. The US was founded on the principle of “all men are equal” and yet slavery existed. This is what resulted in the American Dilemma. Thus, due to historical reasons, and because they are often stereotyped,... |
When a heavy nucleus breaks apart, the two resulting nuclei are more "Tightly bound" than they were before, but why does this mean they have less mass? | Tightly bound means that it takes a lot of energy to separate something into its constituent particles, and since E = mc^(2), this means it gets heavier when it is separated than when it is bound. If it gets heavier when separated, then it must be lighter when bound. In other words, binding energy is negative because y... | [
"The stability of a nucleus is determined by its binding energy, with higher binding energy conferring greater stability. The binding energy per nucleon increases with atomic number to a broad plateau around \"A\" = 60, then declines. If a nucleus can be split into two parts that have a lower total energy (a conseq... |
How would walled cities handle rivers? It seems like building on both sides of a river would create a weakness in the city walls. | You can handle a river in a number of ways, and in flat low-lying areas like Northern Italy the management of natural waterways was one of local authorities' major historic concerns. I wrote about that [here](_URL_4_) in the specific context of Milan and Lombardy.
When constructing a fortification, the easiest way to ... | [
"In larger cities, a moat surrounded the wall. This could be connected to canals or rivers both in the city and outside, thus providing both a defense and a convenient transportation route. Nearby waterways might be adopted or altered to connect to, or form part of, the moat.\n",
"In the Middle Ages, virtually al... |
The largest army to ever invade the British isles... | I've found what [looks](_URL_4_) like the book, and I'm quite confused as to what he's trying to say at all. A bit further down the page he refers to Ivar's 'force of a thousand men' which is within the range of estimates for the size of the Great Heathen Army (though very much on the low side), but is absolutely tiny ... | [
"The British amassed their army, under the command of General James Abercrombie, near the remains of Fort William Henry, which lay at the southern end of Lake George but had been destroyed following its capture by the French the previous year. The army numbered fully 16,000 men, making it the largest single force e... |
Civilizations BC vs AD seemingly less advanced? | Well I ask you, by what standards are we supposed to measure advancement? Is there an end state of all civilizations that we can objectively place each and every society that has ever existed on? Are we supposed to measure advancement by the development of certain technologies or political structures? Seeing as real... | [
"Discovered long after the contemporary civilizations of Mesopotamia and Egypt, the Indus Valley Civilization or Harappan civilization (c. 2400–1900 BCE) is now recognized as extraordinally advanced, comparable in many ways with those cultures.\n",
"Sumer in Mesopotamia, the Indus valley civilization, and ancient... |
if we used nuclear power for everything, how long until we run out? could we get more uranium by then? | Fissionable materials are infinite for all practical purposes.
Uranium can be extracted from seawater in vast quantities because it comprises a significant portion of the Earth's crust. | [
"The European Commission said in 2001 that at the current level of uranium consumption, known uranium resources would last 42 years. When added to military and secondary sources, the resources could be stretched to 72 years. Yet this rate of usage assumes that nuclear power continues to provide only a fraction of t... |
Is there any sense of a 'good v bad' narrative to the First World War as there is in World War II where Germany clearly is/was the bad guy? | Ah… well, this is sort of *the* historiographical debate regarding WW1, and there are several sides to the issue. If you want an extremely short version, people have written books blaming every single belligerent power (often titled some variation of “_____ and the Origins of the First World War”), but the most popular... | [
"Piers Brendon has called it \"the most appalling atrocity story\" of World War I, while Phillip Knightley has called it \"the most popular atrocity story of the war.\" After the war John Charteris, the British former Chief of Army Intelligence, allegedly stated in a speech that he had invented the story for propag... |
can a water bomb be used to extinguish the current california fires? | Technically, yes. But it has to hit a critical mass of the fire all at once.
Right now, multiple mountains are on fire. You'd need to hit it with a literal mountain sized bomb of water at about the same time.
Assuming you pull that off, then you have to deal with the mountain of water that you dumped flooding wh... | [
"Authorities built a temporary pipe to San Juan Bay in order to bring seawater to extinguish the fire, although the fire was extinguished before it could be used. Fire fighting foam was supplied from the nearby United States Virgin Islands. Luis Fortuño announced on October 25 that the fire had been extinguished, a... |
why do the scots simply vote to secede from the uk, but for the southern us states, it resulted in the civil war? | Because the South attacked Fort Sumter. Also they didn't ask the US permission to leave, they told the US they were leaving. | [
"Scottish voters were given the chance to vote 'Yes' on outright independence in a 2014 referendum. In an effort to persuade Scots to remain in the Union, the major UK parties vowed to devolve further powers to Scotland after the referendum. The 'No' vote prevailed (independence was rejected), but the campaign prom... |
Was Constantine XI a good emperor or is his godlike legacy the way it is because he was the last emperor? | Historians don't have much to judge concerning Constantine XI's reign as Emperor, with the main reasons being his short 4 year reign and the sheer hopelessness of his situation he was in. By the time he ascended to the throne, there was really nothing that even the most energetic Emperor could do to stop Mehmed II's im... | [
"Constantine's rule is hard to assess due to the shortness of his reign. As a Despot, he had shown ability, but the fall of the Empire to the Turks was by his time inevitable, no matter how able and energetic an Emperor sat on the throne. What is most remembered of him is the stubborn defence of his city against th... |
why are there ridges on many u.s. coins? | During our country’s earlier years, all coins were made of gold or silver, and did not have ridges. Each coin’s value was based on the amount of gold or silver in it. For example, a $10 gold piece contained ten dollars worth of gold, and silver dimes contained ten cents worth of silver.
But some dishonest people sough... | [
"On the edge of the US dime, quarter and half dollar, and many world coins there are ridges, similar to knurling, called reeds. Some older US coins, and many world coins have other designs on the edge of the coin. Sometimes these are simple designs like vines, more complex bar patterns or perhaps a phrase, as on th... |
passing out from donating blood? | No your body can function without being awake. All your organs are all needed to stay alive. Take being asleep, your organs can't shut down or you'd die, but for the most part your brain shuts down. | [
"The campaign has clarified that donating blood is a permitted and, in fact, a recommended act in Islam. Some eminent religious scholars have issued information regarding the donating of blood and shown support for the campaign.\n",
"Most allogeneic blood donors donate as an act of charity and do not expect to re... |
When the Kingdom of Jerusalem was not at war, was it relatively tolerant to non-Catholics? How did treatment of Sunnis, Shi'as, Druze, and Eastern Christians differ? | It has been a few years since I was really deep in the Crusades research, but for the most part it varied. When Jerusalem was sacked by the first Crusade, all of the non-Christians were killed, including those seeking shelter in religious sites. This led to even more hostilities initially, but many of the zealots soon... | [
"With the death of Saladin in 1193, the Ayyubid Empire disintegrated and was divided among his sons. This led to struggles between various principalities as alliances were formed and dissolved. Jerusalem lost its status as the capital and religious center, and became a provincial city in an empire whose center was ... |
If a lung is punctured where does the air that escapes the lung escape to within the body? | How is the lung punctured? From the outside GSW? Or from the inside (broken ribs) from blunt force trauma?
Usually what happens is the lung collapses. It relies on positive pressure to keep it inflated. This is called [pneumothorax](_URL_0_). When there is blood around the area (usually due to trauma) it's referr... | [
"If the chest wall, and thus the pleural space, is punctured, blood, air or both can enter the pleural space. Air and/or blood rushes into the space in order to equalise the pressure with that of the atmosphere. As a result, the fluid is disrupted and the two membranes no longer adhere to each other. When the rib c... |
the euro: what are some of the consequences of such different sized economies having the same currency? | Devaluing your currency is in this case going to be central bank directed inflation. The European Central Bank has done it with quantitative easing, whereby they buy bad bonds from individual countries, similar to what the U.S. Has done. Where it differs from the U.S. Is that each u.s. State has to balance its budget e... | [
"An optimal currency area is often larger than a country. For instance, part of the rationale behind the creation of the euro is that the individual countries of Europe do not each form an optimal currency area, but that Europe as a whole does. The creation of the euro is often cited because it provides the most mo... |
why can humans not regrow damaged nerve cells? | You cannot grow back *nerve cells*. Nerve cells have very unique morphology (size and shape), which would be very difficult to recreate. There is a small area in the brain where new nerve cells appear, but it has nothing to do with damage.
However, you can actually grow back *nerves*. Nerves are not cells, but rather ... | [
"The possibility for nerve regeneration after injury to the spinal cord was considered to be limited because of the absence of major neurogenesis. However, Joseph Altman showed that cell division does occur in the brain which allowed potential for stem cell therapy for nerve regeneration. The stem cell-based therap... |
what is the sense of having "the right against self-incrimination"? | The whole premise of our legal system is that you're initially assumed to be innocent & the state must prove guilt. Ultimately, it's a protection against torture - if the authorities can force you to confess things, people will get hurt if they're giving the "wrong" answer.
| [
"This provides a right against self-incrimination. \"R. v. Hebert\", [1990] 2 SCR 151 confirms that this right extends to situations where the police employ \"unfair tricks\" such as sending an undercover police officer to pose as a sympathetic cellmate.\n",
"Those who could not be \"insumisos\" (for example, men... |
Is there a simple sequence of moves on a Rubik's cube that will cycle through every possible arrangement? | There is some subtlety here that makes it easy to throw darts at any short answer. Having said that, the short answer is no. :)
(Edited to fix some hyperlinks, and again to say thanks for the gold!)
Consider any particular sequence S of moves, say S=(R'BR) using [Singmaster](_URL_2_) notation. Now imagine applying ... | [
"The table also shows that there is only one combination that is exactly 8 moves away from the solved state; this is the combination in which all the corners are in their correct places but all the edges are flipped, analogous to the \"superflip\" on the Rubik's Cube, which requires 20 moves to solve.\n",
"The mo... |
Why isn't ultraviolet light more commonly used as a disinfectant? | It is very commonly employed to sterilise water in food, chemical and pharmaceutical plants. Any food or pharmaceutical processing equipment supplier will either be able to sell you an industrial one or point you to someone who can. You can buy smaller units for your aquarium from pet stores. Do a search for *UV steril... | [
"Ultraviolet (UV) light can be used instead of chlorine, iodine, or other chemicals. Because no chemicals are used, the treated water has no adverse effect on organisms that later consume it, as may be the case with other methods. UV radiation causes damage to the genetic structure of bacteria, viruses, and other p... |
Was Ser or Sir more commonly used in Medieval Europe? | "Ser" is an invention by *Game of Thrones* author George R. R. Martin.
The English word "Sir" is the only correct honorific for a Knight, and is translatable in Italian as "Cavalier/e" and in French as "Chevalier," however in France all titleholders are addressed with a normal "Monsieur" and "Madame." In Italy, title... | [
"Sir John Fenn (1739–1794) was an English antiquary. He is best remembered for collecting, editing, and publishing the Paston Letters, describing the life and political scheming of the gentry in Medieval England. He was also a justice of the peace who served as High Sheriff of Norfolk for 1791/2.\n",
"The ordinar... |
How do we separate the light beams when looking at the emission spectrum of stars to determine what elements it is composed of? | you use a spectrometer, it basically separates light by bending it. different lights have different wave lengths with different intensity's. we know which elements emit a certain type of frequency and we can physically see the intensity of those frequency and match them up with the light emitted by stars. | [
"The emission spectrum can be used to determine the composition of a material, since it is different for each element of the periodic table. One example is astronomical spectroscopy: identifying the composition of stars by analysing the received light.\n",
"Much astronomical work relies on the study of spectra - ... |
During the Civil War, soldiers would return from battle having not fired a shot at the enemy. Was the common place in WWII as well? | So, the principal study on this comes from 'Men Against Fire' by SLA Marshall, a US Army Historian, who posited that firing rates in most units were below 25 percent. The issue is though, that his work has been *seriously* called into question, and few authorities trust it. I've expanded upon this [here](_URL_0_). | [
"On May 6, 1865, Thomas' Legion fired \"The Last Shot\" of the Civil War east of the Mississippi River in an action at White Sulphur Springs, North Carolina. After his legion captured Waynesville, they voluntarily ceased hostilities upon learning of General Robert E. Lee's surrender and the end of the war.\n",
"A... |
What does it mean if something is one-dimensional? Is such a thing possible in the tangible universe? | A point is zero dimensional. A line is one dimensional.
Some theorised objects such as cosmic strings would be truly one dimensional, but as far as I know, we have not observed a "real" one dimensional structure. | [
"Dimensional analogy was used by Edwin Abbott Abbott in the book \"Flatland\", which narrates a story about a square that lives in a two-dimensional world, like the surface of a piece of paper. From the perspective of this square, a three-dimensional being has seemingly god-like powers, such as ability to remove ob... |
Under the theory of the Big Bang, where did all the universes initial amount of hydrogen come from? | While a lot of energy is required for fusion to occur, the nature of the Big Bang does not really lend itself to the production of heavy atoms. Here's sort of a hierarchy of constraints that limit the production of atoms in the early universe:
1. Light elements were only able to form after the universe had cooled sign... | [
"The Big Bang is thought to be the origin of the hydrogen (including all deuterium) and helium in the universe. Hydrogen and helium together account for 98% of the mass of ordinary matter in the universe, while the other 2% makes up everything else. The Big Bang also produced small amounts of lithium, beryllium and... |
When we say an atom is stable as it has achieved an octet electronic configuration,what do we exactly mean by stable? | An atom is stable if it has a full set of electrons. How many is a full set? 2(N^2 ) where N is the row on the periodic table. When you do the mathematics to solve the hydrogen atom, you find that electrons will distribute themselves into energy levels. The problem is, we can really only solve the hydrogen atom, be... | [
"The physical basis of the chemical periodicity governing the periodic table is the electron shell closures at each noble gas (atomic numbers 2, 10, 18, 36, 54, 86, and 118): as any further electrons must enter a new shell with higher energy, closed-shell electron configurations are markedly more stable, leading to... |
when people get "keys to the city", do those keys open anything or are they purely symbolic. | At this point it is purely symbolic. It used to be in olden days city's would close their gates and lock them at night to protect against raids and what not. Back then being given a key to the city granted you access throughout all hours of the day. That doesn't really happen nowadays so it's just to give honor to the ... | [
"The Key to the City is an award presented by a town or city's municipal government to esteemed residents or visitors whom the city wishes to honour. The award, usually an ornamental key, is generally presented by the mayor or some other public figure at an award ceremony. Some cities allow visiting celebrities to ... |
Have you ever had anything happen that changed the way you looked at science? For me it was learning about 'biological clocks' | > The SCN in mammals is totally controlled by input from the eyes (mainly light in the blue/violet/uvish range, from specialized photoreceptors).
They are actually not photoreceptors, your SCN actually gets input from intrinsically photosensitive retinal ganglion cells. It probably doesn't mean much, just another ce... | [
"BULLET::::- Frank A. Brown Jr. The \"Clocks\" Timing Biological Rhythms: Recent discoveries suggest that the mysterious biological clock phenomenon results from a continuous interaction between organisms and the subtle geophysical environment. \"American Scientist\",Vol. 60, No. 6 (November–December 1972), pp. 756... |
In the Hundred Years' War, the English won several major victories and managed to hold onto French land for over a century. What caused their ultimate defeat? At what point? Was there any real chance of continuing English control in France? | It's very hard to prove a counterfactual like 'could the English have conquered France'. We know they didn't, but whether they could have succeeded requires a lot of speculation. In theory, had the people and nobles of France rejected the Valois monarchy and embraced the Kings of England then sure, maybe Edward III or... | [
"Now the undisputed master of England, Edward invaded France in 1475, but Louis was able to negotiate the Treaty of Picquigny, by which the English army left France in return for a large sum of money. The English renounced their claim to French lands such as Normandy, and the Hundred Years' War could be said to be ... |
are ticks really unkillable? | Ticks are hard to crush because they're very flat and hard, but you can easily kill a tick by cutting it, burning, poisoning, or crushing with a small pressure point. There are more ways to kill a tick than by burning. | [
"It is sometimes thought of as an animal disease. In humans, the primary concern from tick bites is often not the ectoparasitism itself, but the potential for the tick to transmit disease or tick paralysis. Still, in certain populations, it is possible for tick infestation to be clinically significant.\n",
"Ticks... |
what causes some people to keep their eyes open after death and not others? | The opening and closing of eyelids is controlled by the [levator](_URL_0_) and superior tarsal muscles. Which stop working at death. So if they eye is open most likely it will stay open. | [
"In Graves' disease, ophthalmopathy may cause the eyes to look enlarged because the eye muscles swell and push the eye forward. Sometimes, one or both eyes may bulge. Some have swelling of the front of the neck from an enlarged thyroid gland (a goiter).\n",
"When dry eyes symptoms are severe, they can interfere w... |
why the mlb does not have a salary cap | Because the rich teams like to treat the rest of the league as their farm system, and the players like being showered in money.
Since a salary cap has to be part of the union agreement, they work together to make sure that never happens. | [
"As of 2019, Major League Baseball is the only major professional sports league in North America that does not have a salary cap; the MLS, NHL, NBA, and NFL all implement some sort of salary cap. The MLB does have a luxury tax that penalizes clubs that exceed the designated amount for that season.\n",
"MLB is the... |
Could a slave owner arbitrarily confiscate the wealth of a slave saving up to buy their freedom? (Scope: Antebellum US, British & French Caribbean, Roman Republic/Empire) | I can't speak for the Roman Republic (Edit: Looks like /u/XenophonTheAthenian has that covered), but in the United States, slaves could not legally own property in most places. Therefore, a slave owner in the United States could definitely confiscate their slaves' goods. However, this was rarely done for a variety of... | [
"The colony required slave owners who wanted to free their slaves to pay a tax of £200 per person, then an amount much higher than the cost of a slave. In 1715 Governor Robert Hunter argued in London before the Lords of Trade that manumission and the chance for a slave to inherit part of a master's wealth was impor... |
Does "handling your liquor" necessarily equate to your liver/organs being able to process alcohol better? | That is one part. Some of it is genetic, some of it is physical conditioning (a combination of developing more enzymes to digest alcohol and the CNS getting more resistant to the effects), but there is also a strong element of psychological conditioning: basically, people who drink alcohol more are more use to the sen... | [
"An alcohol enema is a faster method of alcohol intoxication since the alcohol is absorbed directly into the bloodstream. The lower gastrointestinal tract lacks the alcohol dehydrogenase enzyme present in the stomach and liver that breaks down ethanol into acetylaldehyde, which is actually more toxic than ethanol (... |
Re-asking/re-formatting question: What is the Historicity and Authenticity of “Bushido”? How did it become nationalized in post-industrial Japan? | There’s a few discussions of bushido on here. I think this one
_URL_1_
Has a good summary by u/paralellpain
Some more from u/nientenada
_URL_0_ | [
"More recently, it has been argued that modern \"bushidō\" discourse originated in the 1880s as a response to foreign stimuli, such as the English concept of \"gentlemanship\", by Japanese with considerable exposure to Western culture. Nitobe Inazo's \"bushidō\" interpretations followed a similar trajectory, althou... |
is it illegal to take money you find on the ground? | Not really. From what I understand, unless someone is actually in distress looking for the money, it's yours.
Just don't go blurting out that you found a 100 dollar bill | [
"Finds of money and lost property are dealt with by other states through legislation. These statutes usually require finders to report their finds to the police and transfer to their custody the objects. The police then advertise the finds to try to locate their true owner. If the objects remain unclaimed for a spe... |
there is currently an ant infestation in my 17th floor office... how the hell did they get here | Ants are very small and thus have a very low mass. Gravity does not overcome the force of friction that the walls give against their feet because their mass is so small. That's why they can climb 20 stories straight up. A more probable idea would be that they have built a presence in the walls of the building over a fe... | [
"A nest of gigantic irradiated ants is discovered in the New Mexico desert; they quickly become a national threat when it is discovered that two young queen ants and their consorts have escaped to establish new nests. The national search that follows finally culminates in a battle with \"Them\" in the concrete spil... |
Shouldn't the objects that made craters on the moon still be in the center of the crater? | "The impactor is shattered into small pieces and may melt or vaporize."
The impactor being whatever smashed into the moon and created the creator.
For more information, check this out:
_URL_0_ | [
"The smallest craters found have been microscopic in size, found in rocks returned to Earth from the Moon. The largest crater called such is about 290 kilometres (181 mi) across in diameter, located near the lunar South Pole. However, it is believed that many of the lunar maria were formed by giant impacts, with th... |
I'm interested in reading about United States Foreign Relations from 1890-1945 | *From Colony to Superpower* (by Herring) might be an overkill as it's about foreign relations from 1776 on, but in my opinion it's the most useful book on US foreign policy. The relevant books of the *Major problems in American foreign relations* series are worth a look, too. Are you interested in a specific part of fo... | [
"The history of U.S. foreign policy from 1913–1933 concerns the foreign policy of the United States during World War I and much of the Interwar period. The administrations of Presidents Woodrow Wilson, Warren G. Harding, Calvin Coolidge, and Herbert Hoover successively handled U.S. foreign policy during this period... |
what is the difference between a movie and film? | Same thing. The term 'movie' is a casual way to say 'moving picture' and it caught on. 'Film' refers to the roll of film that old cameras used to capture action.
Technically, since new movies are shot digitally and not using film, they aren't 'films'.
In conversation, 'film' has a connotation of being something high-... | [
"Film, also called movie or motion picture, is a medium used to simulate experiences that communicate ideas, stories, perceptions, feelings, beauty or atmosphere by the means of recorded or programmed moving images along with other sensory stimulations. The word \"cinema\", short for cinematography, is often used t... |
why do funny things make us curl towards our core and fall over? | Laughing activates the abdominal muscles and diaphragm, we curl over instinctively to ease breathing. | [
"\"The Pedalternorotandomovens Centroculatus Articulosus (curl-up) came into existence (spontaneous generation), because of the absence, in nature, of wheel shaped, living creatures with the ability to roll themselves forward. The accompanying 'beastie' depiction, referred to as 'revolving bitch' or 'roll paunch' i... |
why are pixel graphics games so popular and making a comeback? | It is easier to make them and since it has been such a long time since that kind of graphics were most used, nostalgia has transformed pixel graphics more into an aesthetic style rather than "poor graphics". | [
"Modern pixel art has been seen as a reaction to the 3D graphics industry by amateur game/graphic hobbyists. Many retro enthusiasts often choose to mimic the style of the past. Some view the pixel art revival as restoring the golden age of second and third generation consoles, where it is argued graphics were more ... |
Were there Pre-Colonial permenant farming communities north of Modern-Day Mexico? | Yes, there were.
One of the most famous examples is the [Cahokia site](_URL_0_). A pretty large trading city like that would have required an agricultural base, too.
There weren't any large-scale agriculture civilizations on the scale of the Meso-Americans, but there were agricultural groups in North America.
> no... | [
"The colonial system continued after the Mexican War of Independence, with rural farm workers almost landless, as peons on haciendas. Under the modernization efforts of the Porfirio Díaz regime, these large haciendas were encouraged to develop commercial farming for export, especially the production of henequen and... |
How do we find fossils of Aquatic Life? | Most fossils, regardless of sea or land, are formed when [the body of the animal is buried in mud or silt.](_URL_0_) You are correct that most of the time this does not happen, and decomposers get at the body, or conditions are not right, or it does not get buried fast enough. But sometimes, if the corpse sinks to the ... | [
"The fossil remains of ancient armoured fishes have been found in rocks within the late Silurian/early Devonian-age Lower Old Red Sandstone rocks exposed in local streamsides. Microscopic analysis has found fish scales and fin spines of these ancient fish some 410 million years old. The research carried out by a lo... |
nutritional supplements, what should i be ingesting and what is purely hype? | Honestly, very little of that crap is scientifically proven to do anything except nothing or give you cancer (or something else).
The stuff that does work, only really works if you already have a deficiency in the thing you are taking. You will just pee out $40 of supplement that you already had plenty of.
Ideally, a... | [
"There is little evidence supporting benefits for some supplements, including: the Ayurvedic herbal preparations with brand names Articulin F and Eazmov; Duhuo Jisheng Wan, a Chinese herbal preparation; fish liver oil; ginger; russian olive; the herbal preparation gitadyl; omega-3 fatty acids; the brand-name produc... |
if a cheetah is the fastest animal on earth why are they only successful on a small percentage of their hunts? | They have straight line speed. But a gazelle is good at weaving. Also a cheetah can only keep up the speed for a brief time before it wears out. In fact, the cheetah will often nap before eating if it does catch a gazelle.
Also a cheetah likely won't die if it doesn't catch that gazelle, but the gazelle definitely will... | [
"African cheetahs may achieve successful hunts only running up to a speed of while hunting due to their exceptional ability to accelerate; but are capable of accelerating up to on short distances of . It is therefore the fastest land animal. Because of its prowess at hunting, the cheetah was tamed as early as the 1... |
what do gas stations do with the information they get from scanning/swiping your driver's licence? | It's used by the point of sale software to determine if the purchaser is old enough to buy age-restricted products like tobacco and alcohol. By the store requiring that the clerks swipe/scan the ID, they will get a lot less of "oh, I thought he was old enough, I must have read the ID wrong". | [
"The Commercial Driver's License Information System (CDLIS) and the National Driver Register (NDR) exchange information on traffic convictions and driver disqualifications of commercial drivers. States have to use both CDLIS and NDR to check a driver's record before a CDL can be issued. To gain permission to access... |
The Carolingian's had a series of goofy but straightforward names including Louis the Fat, Louis the Bald, and Charles the Simple. But, how did the Louis the German gain his name? | First, about the names, you can consider them a practical way to differentiate people in a huge family where a lot of them shared the same names. They probably worked in the same way and were influenced by the Roman cognomen. During the Roman era your name was a three part mix of a generic praenomen, taken from a small... | [
"He was named \"Charles\" in French and English, \"Carolus\" in Latin, after his grandfather, Charles Martel. Later Old French historians dubbed him \"Charles le Magne\" (Charles the Great), becoming Charlemagne in English after the Norman conquest of England. The epithet Carolus Magnus was widely used, leading to ... |
Why was Russia allowed a permanent seat on the UN Security Council? | The Russian Federation is the successor state of the USSR under international law, thus inheriting the USSR's UN membership and by extension its permanent seat on the Security Council. | [
"Russia holds a permanent seat, which grants it veto power, on the Security Council of the United Nations (UN). Prior to 1991, the Soviet Union held Russia's UN seat, but, after the breakup of the Soviet Union the Russian government informed the United Nations that Russia will continue the Soviet Union's membership... |
why is there only one variety of banana available for general consumption? | Other species of banana have been developed and sold. They don't travel as well as the Cavendish, so they are more expensive. The Lady's Finger banana is sometimes on sale in the US, and it's actually the taste that banana flavorings are trying to duplicate.
But small expensive bananas don't get chosen when there ar... | [
"Worldwide, there is no sharp distinction between \"bananas\" and \"plantains\". Especially in the Americas and Europe, \"banana\" usually refers to soft, sweet, dessert bananas, particularly those of the Cavendish group, which are the main exports from banana-growing countries. By contrast, \"Musa\" cultivars with... |
when people collect large amounts of trash from the ocean and beaches, what ensures them that the trash won't end up back there? | Typically any trash collected from beaches and the ocean is resulted from littering or spills. Once the trash is placed in a landfill, it's highly unlikely to end up anywhere else. | [
"Marine debris is a problem created by all of us, not only those in coastal regions. Ocean debris can come from as far away as Nebraska. The places that see the most damage are often not the places that produce the pollution. For ocean pollution, much of the trash may come from inland states, where people may never... |
why do humans sweat after eating chilli or spicy food in general? | The spicy chemical in chili works by confusing the heat sensors in your mouth. They tell your brain that there's something hot there, even when there isn't. Your brain's reaction to detecting heat is to start sweating to reduce the heat. | [
"Gustatory sweating refers to thermal sweating induced by the ingestion of food. The increase in metabolism caused by ingestion raises body temperature, leading to thermal sweating. Hot and spicy foods also leads to mild gustatory sweating in the face, scalp and neck: capsaicin (the compound that makes spicy food t... |
how do social websites like facebook, linkedin and twitter know to suggest people that i haven't spoken with in 10 years or only had very brief dealings with a long time ago? | Friends of friends. Someone on your friend list may have recently spoken or friended one of those people.
School association. Some of those people may have reported as being in the same high school or college as you.
| [
"This communication also allows an individual to take their time when speaking with someone. They do not have to have an immediate response that face-to-face conversation requires. This allows them to carefully select and edit their messages and gives them more control over their side of the conversation that they ... |
Why is the eastern United States mostly temperate deciduous forest and western United States mostly temperate rain forest? | Airflow at that latitude come mostly from the west. West of the West Coast is ocean, west of the East Coast is land so there is a big difference in rainfall and humidity. Then there are the mountains in the west forcing air upwards, cooling it and making it able to hold less moisture before it moves further inland. | [
"Subtropical forests are found in the United States along the southern border states. These forests are made up of evergreen species and deciduous species. Evergreens are plant species that retain their leaves year round while deciduous trees lose their leaves annually. The consistent warm climate along with consis... |
How did people get enough to eat outside of harvest season? | Lets rephrase that a bit :
Does grain keep for an entire year **nowadays** ? and the answer to that is : Yes it does.
Dried fruit /grain can be stored for a long time if they are stored correctly. If you look at a pack of lentils that you buy today you will see a "to be consumed" date that is about 2 - 3 years in t... | [
"The people made use of the land by \"eating the seasons.\" With a lack of fresh foods in the winter, during the autumn months, the Oneidas dried fruits and vegetables which they had harvested. They also preserved meats in a brine or salt solution, and then hung them to dry. During the fall they would eat deer, gee... |
Why do some animals form geometric patterns on their skin? | In many cases, this is likely to be [disruptive coloration](_URL_1_), a type of camouflage that breaks up the outline and features of the animal, and makes it appear similar to the natural colors and contrasts in the environment.
In other cases, the markings may be [distractive](_URL_0_), which are meant to draw a pre... | [
"Patterns often have their origins in early ideographs. Geometric patterns and patterns of plant, animal and nature motifs are the four most basic patterns. Geometric patterns include triangles, squares, diamonds, zigzags, latticework, frets, spirals sawteeth, circles, ovals and concentric circles. Stone Age rock c... |
why do coaches/trainers tell you to stand up to breathe when you're exhausted? | No, the most "open" position for your lungs is upright with your arms above your head. It allows your diaphragm to move (forcing air in and out of your lungs) more effectively. Hunching over just restricts this action making breathing less effective and even harder. | [
"A way to improve breathing from the diaphragm is to lie on your back on a flat surface. Your goal will be to fill your lungs from the bottom causing your stomach (and diaphragm) to rise and fall. To increase resistance put a small amount of weight (such as a book) on your diaphragm and repeat this exercise. Try st... |
why can bugs climb nearly any surface? | Claws. Teeny tiny claws.
At that scale, a surface we see as smooth is actually pitted and gnarled. They just use their claws and hang on.
No insect could hang onto a perfectly smooth surface, but it would take a hell of a lot of engineering to get to that point. | [
"These bugs give the illusion of sand floating around. They can consume large volumes of water at a rapid rate considering they are such small entities. They seem to be intelligent creatures and are passive and helpful unless provoked, in which case they can be extremely lethal. They fly around in \"swarms\" and wi... |
Size versus time perception. | The short answer is no, it would not be the same. When you make something that big that is the same shape, a dramatic difference develops between the surface area and the volume, and the creature's mass grows much more quickly than a linear feature like the length of a limb or the surface area of a muscle. This will ha... | [
"A temporal dimension is a dimension of time. Time is often referred to as the \"fourth dimension\" for this reason, but that is not to imply that it is a spatial dimension. A temporal dimension is one way to measure physical change. It is perceived differently from the three spatial dimensions in that there is onl... |
do all wifi routers have both 5ghz and 2.4ghz wifi? | You would see a second SSID with a 5ghz label.
E.g. SSID = HomeInternet You would see a HomeInternet (5ghz).
Not all routers have it but most newer ones do. | [
"Some devices with dual-band wireless network connectivity do not allow the user to select the 2.4 GHz or 5 GHz band (or even a particular radio or SSID) when using Wi-Fi Protected Setup, unless the wireless access point has separate WPS button for each band or radio; however, a number of later wireless routers wit... |
why do a lot of people go through a phase in which they hate themselves? | Essentially it's because people naturally compare themselves to everyone around them - including the ridiculously extreme examples in the media.
Noone can measure up to every example they see, and many times the issue is compounded by conflicting ideals (big strong man vs in touch with feminine side vs rich professio... | [
"Because it is such a distinct change, the diversion of hatred towards a new target is necessarily predicated upon the antagonist both diverting hatred away from themselves and fostering a level of anxiety that cannot be mitigated by their existing cause or leadership.\n",
"Hateful intergroup conflict may be moti... |
how is something in orbit "constantly accelerating" towards the thing it's orbiting? | If it were not accelerating, then it would travel in a straight line (at a constant speed) - so it would not be in orbit, but would fly off in a straight line!
Here's an easy way to think about it:
Suppose you have a ball on a string, and you swing it over your head in circles. The *tension* in the string means it i... | [
"An object moving in a circular motion—such as a satellite orbiting the Earth—is accelerating due to the change of direction of motion, although its speed may be constant. In this case it is said to be undergoing \"centripetal\" (directed towards the center) acceleration.\n",
"In practice, this is accomplished by... |
is it possible to make an electronic device to recognize smell? | [Sure, they've been around for more than a decade.](_URL_0_)
The device just needs to be able to identify airborne molecules. Biological noses have special receptors which particular molecules fit into like a puzzle piece. The combination of activated receptors is identified by your brain as a smell. Electronic nos... | [
"Conventional electronic noses are not analytical instruments in the classical sense and very few claim to be able to quantify an odor. These instruments are first 'trained' with the target odor and then used to 'recognize' smells so that future samples can be identified as 'good' or 'bad'.\n",
"In 2013, a group ... |
why would it be devastating to the human race if we found proof of extraterrestrial life? | > Couldn't only good things, especially for Science, come from knowing?
Not every scientific breakthrough is good. We could say achieving nuclear fusion has not been the best of times, amirite?
The thing is, I don't think it would be mass hysteria. I mean, some people might freak out, others would probably serious... | [
"Since the history of life on Earth gives some idea of what is and is not feasible on other worlds, and there is no conclusive evidence of any past extraterrestrial genetic manipulation in our own evolution, some ufologists have offered alternative explanations to accommodate for the evolutionary improbability of G... |
how do scientists know the mass of the obervable universe? | I imagine it's how you find the mass of any other large space. Like in forest scouting rangers actually go and survey a specific unit of the forest like a square mile or something and then count how many trees are in it then scout out another square mile elsewhere in the same forest. After you've surveyed enough square... | [
"The mass of the observable universe is often quoted as 10 tonnes or 10 kg. In this context, mass refers to ordinary matter and includes the interstellar medium (ISM) and the intergalactic medium (IGM). However, it excludes dark matter and dark energy. This quoted value for the mass of ordinary matter in the univer... |
what determines what art is a masterpiece? | Valuable art is that which changes the story of art. It explains how we got from A to B, in art books and art museums.
It doesn't matter if an average person likes art, for it to be valuable or not. For high monetary value it only matters if certain influential people like it. Most importantly, it matters if other art... | [
"In modern use, a masterpiece is a creation in any area of the arts that has been given much critical praise, especially one that is considered the greatest work of a person's career or to a work of outstanding creativity, skill, profundity, or workmanship. The term is often used very loosely. For example the novel... |
why haven't humans evolved to have a higher
pain threshold? | And on the flipside, if you sprained your ankle in the middle of town and didn't have pain, you'd probably walk around on it all day and make it worse. | [
"Pain's intensity is distinct from its unpleasantness. For example, it is possible through psychosurgery and some drug treatments, or by suggestion (as in hypnosis and placebo), to reduce or eliminate the unpleasantness of pain without affecting its intensity.\n",
"It could be argued that a high cognitive ability... |
What is the range of the electromagnetic spectrum that a digital camera can detect? | The technological basis of a digital camera is a charge coupled device (CCD), which has a material whose electrons are dislocated when light hits, then uses a voltage to run those electrons into a circuit (a simplication). CCDs can be used up to the [x-ray range](_URL_1_), and down to the [microwave level](_URL_0_). | [
"Modified digital cameras can detect some ultraviolet, all of the visible and much of the near infrared spectrum, as most digital imaging sensors are sensitive from about 350 nm to 1000 nm. An off-the-shelf digital camera contains an infrared hot mirror filter that blocks most of the infrared and a bit of the ultra... |
how did east germans make the transition towards a capitalist society? | At unification people had 2 years to file ownership claims to the Treuhand (Trust Agency that inherited state-property from the GDR). Claims were invalid if they were made on the basis of Soviet, Nazi, or GDR seizures. Determining who owned what in 1933 and who was the rightful heir in 1990 was a major undertaking.
... | [
"The economic challenges facing East Germany were already formidable by 1960. The mandate Walter Ulbricht gave to the new Economic Commission was summed up in the mantra which the leader liked to repeat. East Germany should \"overtake without catching up\" (\"\"uberholden ohne einzuholen\"\"). East Germans must be ... |
While playing Battlefield One, I began to wonder about the weapons. How often would a common soldier have an automatic weapon? | The answer to the former question is rarely. Considering the number of troops fielded by the German Army, roughly 5,000 of the well known MP18 saw service during the war though approximately 10,000 were made. These were mostly supplied to German Stosstruppen, or stormtroopers. Considering the low number manufactured, v... | [
"BULLET::::- \"I was in the hospital, and a soldier in the bed beside me asked: ‘Why do our soldiers have only one rifle for two or three of our men, when the Germans have automatics?’ So I designed one. I was a soldier, and I created a machine gun for a soldier. It was called an Avtomat Kalashnikova, the automatic... |
How does our atmosphere not dissolve away into space? | It's bound to the Earth Gravitationally. However, molecules/atoms are constantly being ejected into space. There is a minimum velocity required for a particle to 'escape' into space. Simply called the escape velocity. Now, from statistical mechanics we know that the velocity of the particles in a volume of gas is a dis... | [
"A planet can be stripped of its atmosphere (or parts of the atmosphere) due to high energy photons and other electromagnetic radiation. If a photon interacts with an atmospheric molecule, the molecule is accelerated and its temperature increased. If sufficient energy is provided, the molecule or atom may reach the... |
what effect does more cores and slower speed have on a cpu versus having less cores and a higher speed? | A simple way to think of it is like a highway. A quad core only has four lanes, but a higher speed limit. The 8-core has 8 lanes but a slower speed limit. The 8 lane highway will be able to processes more cars/second, but no car will go quite as fast as on the four lane highway with the higher speed limit. | [
"Increasing the speed of the CPU becomes harder, because the speed of all the devices must increase as well. When it is not practical or economical to have all devices as fast as the CPU, the CPU must either enter a wait state, or work at a slower clock frequency temporarily, to talk to other devices in the compute... |
Why has Western Classical Music become so popular in China? | Care to elaborate on why you think this? | [
"Some forms of traditional music were also excluded at various times. In mainland China after 1949, folk music was promoted but classical Chinese music was also condemned as decadent and reactionary and became sidelined. During the Cultural Revolution classical Chinese music virtually disappeared, and some only sur... |
What makes gold so much more malleable than other metals? | Metals are almost always formed of many small crystals or grains. Within each crystal, the atoms are organized in a [lattice structure](_URL_4_), of which several different types exist (for the record, gold is face-centered cubic, FCC).
When you deform metal, you're actually breaking up the structure of the lattice in... | [
"Gold has been used as money for many reasons. It is fungible, with a low spread between the prices to buy and sell. Gold is also easily transportable, as it has a high value to weight ratio, compared to other commodities, such as silver. Gold can be re-coined, divided into smaller units, or re-melted into larger u... |
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