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how is it that i remember hundreds of lyrics when i sing along to songs, but i mix them up or forget parts when i try to sing a capella or to instrumental song versions? | Because you are actually singing with a very very small delay to the actual lyrics, at least the beginning of each line or so, because you can probably finish the lyrics if you have he beginning. | [
"I try not to get too specific so that people can apply the lyrics to their own lives. When I was growing up and listening to the radio and I would hear a song that reminded me of a certain person or a situation or whatever, I would want to be able to completely connect it to that moment. And then if I heard someon... |
Why exactly do migrating birds move from north to south or vice versa in one long event, rather than gradually moving around throughout the year? | Well, first of all, there are several types of migration, and there are some forms that are more similar to your description. Those are usually called Irruptive Migrations. But basically, most Migration depends on food amounts. Birds typically migrate when there is no more food in their current environment and decide t... | [
"Most migrations begin with the birds starting off in a broad front. Often, this front narrows into one or more preferred routes termed flyways. These routes typically follow mountain ranges or coastlines, sometimes rivers, and may take advantage of updrafts and other wind patterns or avoid geographical barriers su... |
If I were to strike a tuning fork in space(without dampening from air), would the metal vibrate indefinitely? Would this be an effective way to store energy? | No, the attenuation caused by the vibrating material would eat up the energy. You might heat up the object a bit as a result, or cause some plastic deformation. | [
"BULLET::::- Reduction of resonance: Essentially any piece of metal or glass has certain frequencies to which it is susceptible to resonate. A machine that resonates would make a tremendous noise. Resonance also occurs in enclosures, such as when echoes reverberate in an ocarina or the pipe of a pipe organ.\n",
"... |
Who is our evolutionary "common ancestor"? | > the prevailing theory is that we have not evolved from chimpanzees
No, but we do share a common ancestor with them that lived 6 million years ago. This ancestor was not a chimpanzee and it was not a human. it was it's own unique species that would split into two lineages, one which would evolve into the Homo lineag... | [
"In biology and genealogy, the most recent common ancestor (MRCA, also last common ancestor (LCA), or concestor) of any set of organisms is the most recent individual from which all the organisms from such set are directly descended. The term is also used in reference to the ancestry of groups of genes (haplotypes)... |
why do humans get headaches? is there a sole reason or is it a combination of factors? and does the factor(s) also cause migraines? | The exact mechanism that causes headaches isn't/aren't yet fully understood. All we know is that there are many known factors that can trigger it. Like blood vessel constriction/dilation, and a change in hormone levels. (And that's also why more women suffer headaches than men.)
Certain patterns of brain activity hav... | [
"Migraines are currently thought to be caused by dysfunction of the nerves in the brain. Previously, migraines were thought to be caused by a primary problem with the blood vessels in the brain. This vascular theory, which was developed in the 20th century by Wolff, suggested that the aura in migraines is caused by... |
Looking for WW1 combat reports from units issued body armor | You'd have to dig in the archives for actual military documents, but you might take a look at Bashford Dean's [Helmets and Body Armor in Modern Warfare](_URL_0_) (1920), which covers many types of body armor used by different nations in WWI, including some data from empirical testing, reports from the field, etc. | [
"The medal was originally designed for presentation to combat engineers, as well as members of the artillery, anti-aircraft and anti-tank who supported infantry units in combat. It could also be awarded to medical personnel attending to battlefield casualties in \"close combat conditions\". Prior to the introductio... |
Is it possible for humans, in the far future, to colonize a planet moving at such a speed that time moves 50% slower than at Earth? | Well, that means it's moving at 86% the speed of light relative to some frame (let's say, the CMB anisotropy frame). That's really fast. The fastest known orbital system is the star S2 which orbits the supermassive black hole in the center of our galaxy, and it moves about 2% the speed of light. So to answer your quest... | [
"The above concepts which appear limited to high, but still sub-relativistic speeds, due to fundamental energy and reaction mass considerations, and all would entail trip times which might be enabled by space colonization technology, permitting self-contained habitats with lifetimes of decades to centuries. Yet hum... |
the assad regime | Heads up, there are serious conspiracy theorists on both sides of this issue right now from T_D and Trump/Putin truthers.
If you want to learn about geopolitics, this NOT the place. If you want an ELI5 you WILL get garbage. Even if it is a long explanation or seems to make a lot of sense, you need to understand geopoli... | [
"The U.S. imposed limited sanctions against the Assad government in April 2011, followed by Barack Obama's executive order as of 18 May 2011 targeting Bashar Assad specifically and six other senior officials. On 23 May 2011, the EU foreign ministers agreed at a meeting in Brussels to add Assad and nine other offici... |
How realistic was Churchills plans to invade Russia in WW2? Could it have succeeded? | Which plan of Churchill are you asking about? Both the planned [Operation Pike](_URL_0_) and [Operation Unthinkable](_URL_1_) would have involved offensive operations against the Soviet Union. There were also [Franco-British plans to intervene in the Winter War](_URL_2_) against the Soviet Union. | [
"Overseen by Brigadier General Dwight D. Eisenhower, the plan was developed in 1942 and reflected American enthusiasm for an early entry into Europe. Senior British commanders and politicians were reluctant to commit themselves to the invasion plan; mindful of the painful losses during the Battle of the Somme (on t... |
How old is the oldest DNA/RNA that has been extracted? Is it the same as the molecules all living organisms have in their cells now? Did nucleic acids evolve or are they the same as they were when life began 4 billion years ago. | DNA will break down over time. The oldest DNA ever reliably recovered was a couple hundred thousand years old, so fantasies of recovering 100 million year old dinosaur DNA are not realistic.
Even in creatures that have stayed relatively unchanged over time (like crocodiles) their DNA continues to mutate and change sli... | [
"DNA contains the genetic information that allows all forms of life to function, grow and reproduce. However, it is unclear how long in the 4-billion-year history of life DNA has performed this function, as it has been proposed that the earliest forms of life may have used RNA as their genetic material. RNA may hav... |
what this tesla model s thing is about? | 1. A New York Times reviewer wrote up a description of a trip he took in a Tesla car. He described instances where the car didn't get as much mileage as Tesla claimed, and that at one point the car ran out of power and he had to have the car towed.
2. The head of Tesla called him a god damn liar (I'm paraphrasing here... | [
"\"Road and Track\"s Bob Sorokanich said the \"Model 3 proves that Tesla is thinking far beyond the edges of the Model S and X. Stepping out of the 3, you realize that, as far as the S and X pushed the envelope, they were always meant as intermediaries, stepping stones designed to draw people away from comfortable ... |
if the french helped us with the american revolution, gifted us the statue of liberty, and we liberated them from the nazi's, why is there a mutual dislike of eachother? | I'm not exactly a representative sample, but I'm French and I can give you my two cents on the subject.
I don't think Americans and French people hate each other, at least not the individuals. I don't know many people in France who hate Americans, and I've been to Minnesota twice and have always been very well receiv... | [
"Édouard René Lefèbvre de Laboulaye () (18 January 1811 – 25 May 1883) was a French jurist, poet, author and anti-slavery activist. In 1865 he originated the idea of a monument presented by the French people to the United States that resulted in the Statue of Liberty in New York Harbor. He got the idea thinking tha... |
can somebody please explain what /r/galacticpeacekeepers and all the associated subreddits are? | Red, Green, and Blue took over The Seventh World and enslaved its inhabitants. The Galactic Peacekeepers are trying to free them. | [
"BULLET::::- The Watchdogs (various voices) – The Watchdogs are small eyeball-headed creatures that serve as Hater's minions and the bulk of his army. They are loyal to their master, but are frequently distracted by Wander's interference, particularly as their \"enemy\" treats them better than their ruler. Many epi... |
what property in substances cause light to speed up or slow down | Light is an electromagnetic wave. The atoms in a substance act as barriers to the propagation of the wave. At each barrier, the wave bends and interferes with other parts of the wave. All-in-all the wave will interfere with itself in such a way as to bend AND slow down the resulting wave crests, even though each par... | [
"When light propagates through a material, it travels slower than the vacuum speed, . This is a change in the phase velocity of the light and is manifested in physical effects such as refraction. This reduction in speed is quantified by the ratio between and the phase velocity. This ratio is called the refractive i... |
Why was Vietnam able to transition to capitalism from a failing socialist state when the USSR collapsed attempting to do so? | You're conflating economic reform with changes to political structures. The Soviet Union "collapsed" because it gained a leader that was no longer willing to enforce the party's monopoly on power, not because it attempted to reform its economics. Yes, the economic aspects of perestroika (a communist-based reform inte... | [
"The fall of communism in the Eastern Bloc and the dissolution of the Soviet Union in 1991 led the Vietnamese leadership to distinguish between economic and political reform – believing the former led to the fall of communism in Eastern Europe. Despite vague references to \"imperialist and reactionary forces\", the... |
What was Gettysburg all about? | Lee was coming off an absolutely devastating victory over the Union army under Hooker at the Battle of Chancellorsville. His decision to invade the north was based on a few things:
* He avidly read antiwar ("Copperhead") newspapers from the North, which led him to believe that the Union population was war-weary and re... | [
"BULLET::::- Gettysburg Address helped redefine two war goals of the Union in the Civil War and the nature of U.S. nationalism. It is considered one of the masterpieces of English literature, and generally follows the form of Pericles' Oration. 1948 Issue.\n",
"The Gettysburg Address is an unreleased American doc... |
What's up with this postcard? | Was it common for Japanese soldiers to carry postcards into battle? What does the postcard say? For some context, this was taken off of a Japanese soldier during WW2 by a friend of mine's grandfather during his time in the Pacific theatre. | [
"Another form of collecting regards postcards, a document written on a single robust sheet of paper, usually decorated with photographic pictures or artistic drawings on one of the sides, and short messages on a small part of the other side, that also contained the space for the address. In strict philatelic usage,... |
How were ancient oral epics like the Iliad, the Odyssey, the Gilgamesh epic, etc. recited? | Your guesses are spot on. These epics are broken into pretty discrete episodes, and you'll see scholars referring to "The Song of Diomedes" as a unit of the Iliad (that being the section where Diomededs leads the Greeks and wounds Venus). The rhapsodes who performed these pieces would choose an episode, or perform an e... | [
"It has been shown from comparative study of orality that the \"Iliad\" and \"Odyssey\" (as well as the works of Hesiod) come from a tradition of oral epics. In oral narrative traditions there is no exact transmission of texts; rather, stories are transmitted from one generation to another by bards, who make use of... |
how cloud storage systems (email, google drive, onedrive) don't run out of storage | The very simple answer is that they can always add mode storage as usage grows. Same way you can add storage to your home system. | [
"The introduction of cloud based storage, means portable operating systems are free of the need to store data locally. The unbundling of the office application data and other user data from the drives containing the operating systems has been a key factor in making BYOOS possible.\n",
"The operating system automa... |
How strong is the force that repels electrons? | Strong enough to keep you from falling through whatever you're sitting on right now. | [
"The effective range of the weak force is limited to subatomic distances, and is less than the diameter of a proton. It is one of the four known force-related fundamental interactions of nature, alongside the strong interaction, electromagnetism, and gravitation.\n",
"Being the weakest of the weakest chemical for... |
Why/how do fish demonstrate vigor at temperatures that render reptiles and amphibians immobile? | I am admittedly not a physiologist so my answer is a bit limited in scope, but I can get us started.
On average, water is much colder than the air temperatures of areas that reptiles and amphibians inhabit. Because of this, the fish’s enzymes and metabolism have evolved to operate at these low temperatures, while the ... | [
"In some fish, a rete mirabile allows for an increase in muscle temperature in regions where this network of vein and arteries is found. The fish is able to thermoregulate certain areas of their body. Additionally, this increase in temperature leads to an increase in basal metabolic temperature. The fish is now abl... |
the two dollar bill. | I'm going to assume you're from the US.
Two dollar bills make up a small amount of the notes in circulation, but they are still being produced so they aren't "rare" like old prints and other collectable currency.
If you consider the other denominations they seem like a sensible fit: $1, $2, $5, $10, $20, $50, and $10... | [
"The United States two-dollar bill ($2) is a current denomination of U.S. currency. The portrait of Thomas Jefferson, the third President of the United States (1801–09), is featured on the obverse of the note. The reverse features an engraving of the painting \"Declaration of Independence\" by John Trumbull. \n",
... |
why do american corporations have the same constitutional rights as citizens? isn't this the reason they are able to become so corrupt and able to get all their power and control? | First, as pointed out below, corporations do not have the same rights as people, but they do have a certain legal personhood, which includes some rights.
Why? Well, it's sort of the point of a corporation. The while idea, since they first came into existence, was that the corporation existed as a distinct legal entity... | [
"In addition, from the perspective of business ethics it might be argued that chief executives are not inherently more evil than anyone else and so are no more likely to attempt unethical or illegal activity than the general population. Large multi-national corporations do continue to attempt to erode governmental ... |
why don't web pages refresh automatically after failing to load the first time? | A browser doesn't necessarily know what's slowing down the network. All it knows is that the server has told it more data is coming, but has not yet been provided.
A few reasons that the data isn't there yet:
* It hasn't been generated yet
* It is stuck on a slow transit (satellite)
* The pre-routed network path has... | [
"After the first page load, all subsequent page and content changes are handled internally by the application, which should simply call a function to update the analytics package. Failing to call said function, the browser never triggers a new page load, nothing gets added to the browser history, and the analytics ... |
does being under anesthesia "count" as sleep to your body? | There is a small amount of similarity in terms of electrical activity, but the two processes are chemically distinct.
The real difference however comes from the surgical procedure you are likely receiving, the stress, cortisol, sympathetic activation produce a vastly different physiological state to natural sleep. | [
"In this level called \"moderate sedation/analgesia\" or \"conscious sedation\", a drug induced depression of consciousness during which the patient responds purposefully to verbal commands, either alone or accompanied with light physical stimulation. Breathing tubes are not required for this type of anesthesia. Th... |
why is it so difficult to delete online accounts? | With some technical background I can say it is very hard to truly delete data, and I don't mean restoring something delete from a hard drive. Lots of information is stored in databases, these databases have different tables, in a reddit world there is likely a table with user names, one with upvotes and one with commen... | [
"In Jun 2018 email from fotki.com to one of the members stated \"In order to keep quality of our service we remove old unused accounts. We've noticed that you didn't use your account at fotki.com for a year. That's why your account is queued to be deleted in 2 days\". There is no option to reactivate account withou... |
what a "non-member observer state" is? | State = The UN recognizes Palestine as a country
Observer = Palestine can send a representative to listen to UN meetings
Non-member = Palestine's representative can't vote on UN issues | [
"Observer status may be granted by a United Nations General Assembly resolution. The status of a permanent observer is based purely on practice of the General Assembly, and there are no provisions for it in the United Nations Charter. A distinction has been made between state and non-state observers. Non-member sta... |
What is the most realistic answer to the question of how earlier humans consistently (or inconsistently) made fire without proper fire making tools? | Hi there -- while this question may garner some answers here, you may also want to crosspost it to r/askanthropology. | [
"The use of flint in particular became the most common method of producing flames in pre-industrial societies (see also fire striker). Travelers up to the late 19th century would often use self-contained kits known as tinderboxes to start fires.\n",
"The discovery and utilization of fire, a simple energy source w... |
Cooling without fridge? | There are many different refrigerator designs. Some of them can be used without electricity.
The simplest wayto cool a liquid is by evaporation and this is still used in some places by putting water in earthenware pots. The pot is porous and the liquid will go thought the pores and evaporate, taking away heat from th... | [
"A refrigerator (colloquially fridge) consists of a thermally insulated compartment and a heat pump (mechanical, electronic or chemical) that transfers heat from the inside of the fridge to its external environment so that the inside of the fridge is cooled to a temperature below the ambient temperature of the room... |
What did Medieval people think about elves? | This question is *extremely* difficult to answer for two reasons:
1) the evidence for how people conceived of elves is very, very thin and 2) the evidence we do have suggests a wide range of beliefs that vary dramatically between places and across the centuries. Still, your question deals with pre-Norman England, so l... | [
"Beliefs about elves have their origins before the conversion to Christianity and associated Christianization of north-west Europe. For this reason, belief in elves has, from the Middle Ages through into recent scholarship, often been labelled \"pagan\" and a \"superstition\". However, almost all surviving textual ... |
From an engineering perspective, why don't recreational boats have a transmission? | For the same reason you don't have to use a clutch to get a boat going. The propeller can "slip" against the water and essentially acts as a CV transmission, delivering the torque of the engine directly as a force against the water. There is no need for gears because there is no reason for the propeller speed to exactl... | [
"Traditional sailboat transmissions consist of a simple horizontal output shaft extended rearward from the engine, through the stern via a stuffing box. The saildrive has several advantages over the traditional sailboat transmission: smaller horizontal size, no stuffing box to maintain, and the propeller is mounted... |
How did the Sassanid Empire deal with Huns? Why were they able to resist them while the Romans weren't ? | There were several waves of Hunnic people the Sasanians faced beginning with those known in the Latin sources as the Chionites but including the Kidarites and Hephthalites as well. The short story is that they did not resist them very well. From the limited sources we know of many campaigns in the east against the Huns... | [
"Until the Sassanids came to power, the Romans were mostly the aggressors. However, the Sassanids, being Persians, were determined to reconquer lands that the Achaemenid dynasty had once held and now lost. Their nationalistic zeal made them much more aggressive foes of the Romans than the Parthians ever were. For m... |
What civilisations spent their entire history as Nomadic or semi-nomadic? | What do you consider a civilization? Consider all the people who lived in and around the Central Asian steppes -- Scythians, Sarmatians, Mongols, etc. Also some of the Plains Indians in the Americas. | [
"The nomadic way of life has become increasingly rare. Many governments dislike nomads because it is difficult to control their movement and to obtain taxes from them. Nomadic migration across international boundaries confuses capital-city bureaucrats. Many countries have converted pastures into cropland and forced... |
why do low-resolution videos viewed in full-screen look blurry and not pixelated? | Because the program you're using decided that it would handle stretching videos by blending colors together instead of pixelating it. | [
"Because the human eye is much more sensitive to small changes in brightness (the Y component) than in color (the Cr and Cb components), chroma subsampling is a very effective way to reduce the amount of video data that needs to be compressed. On videos with fine detail (high spatial complexity) this can manifest a... |
what is group velocity and how can it be faster than the speed of light? | Physics Grad Student here.
So what is important is the assumption that "nothing can move faster than light". This is something you always hear which, however is not actually true. The speed of light as a maximum limit of speed is only restricted to the transmission of *information*. The correct phrasing would thus be:... | [
"The group velocity is often thought of as the velocity at which energy or information is conveyed along a wave. In most cases this is accurate, and the group velocity can be thought of as the signal velocity of the waveform. However, if the wave is travelling through an absorptive or gainful medium, this does not ... |
What, besides the ship skin, protects cosmonauts from solar radiation during the long stay in space? | It is probably the case that some elevated level of radiation exposure is going to be necessary for interplanetary travel. The primary defense against radiation-induced harm is to track individual astronauts' radiation exposure over their entire lifetime and design missions that are short enough so that everybody accum... | [
"Although the spacecraft itself somewhat reduces radiation exposure, it does not completely shield astronauts from galactic cosmic rays, which are highly energetic heavy ions, or from solar energetic particles, which primarily are energetic protons. By one NASA estimate, for each year that astronauts spend in deep ... |
why is salmon the only fish that is smoked? | It's not. My favorite is smoked haddock aka finnan haddie. Smoked whitefish is a standard at Jewish delis. Smoked trout, smoked herring (kippers)...and of course smoked oysters. | [
"Smoked salmon is a preparation of salmon, typically a fillet that has been cured and hot or cold smoked. Due to its moderately high price, smoked salmon is considered a delicacy. Although the term lox is sometimes applied to smoked salmon, they are different products.\n",
"A common name for cold-smoked salmon is... |
why society shelters children from knowing about sexuality | Because Jesus doesn't like it. And if you ask me again God's gonna punish you. Now go to your room. | [
"Adolescent children are usually segregated in school by sex, because they want this to be a place for education and not entertainment or romance. Thinking that sex education would lead to desire and trouble. The main exception to this occurs during festivals, especially the New Year Festival, when boys and girls t... |
how do the toasters at subway get a crispy toast so fast | Used to work at Subway, those ovens are always around 500°. Like melt your glove to your hand hot. That's why we used a paddle to insert/remove subs. | [
"Toaster Strudel is a toaster pastry convenience food, prepared simply and quickly by heating them in a toaster and then spreading the included icing packet on top. The brand is historically notable for being stored frozen, due to innovations in 1980s food manufacturing processes.\n",
"Conveyor toasters are desig... |
why is the earth elliptical? | When stuff is in space, there's nothing to keep it flat. If something is small, big things make them go nearer - it's like when you jump, you go back to the ground because it's so much bigger than you. When you get a lot of things together with nothing else around, they stay together. And the more things you have, the ... | [
"The \"T and O\" shape does not imply that its creators believed in a flat Earth. The spherical shape of the Earth was already known to the ancient Greeks and Romans and the idea was never entirely forgotten even in the Middle Ages, and thus the circular representation may well be considered a conventional attempt ... |
why do some games have a problem with cheaters(cs:go) and some don't(rocket league)? | For one, you need a good easy way to cheat. You can do this by either giving you an unfair advantage, (Like giving you more info than the opponent) or by letting the computer do stuff for you its very good at, that humans are bad at.
So in Counter Strike, you can have the computer give you an unfair advantage by givin... | [
"There are many facets of cheating in online games which make the creation of a system to stop cheating very difficult; however, game developers and third party software developers have created or are developing technologies that attempt to prevent cheating. Such countermeasures are commonly used in video games, wi... |
What happened to Russian citizens after the purchase of Alaska? | Howdy!
When the United States purchased Alaska from the Russian Empire there was a treaty signed by both governments. The treaty was known as the Treaty of Cession. It was signed by the Emperor of All the Russias, Alexander II and was ratified by the United States Congress. Within the Treaty lies the answer to your qu... | [
"In the present-day Russian Federation and its predecessor the Soviet Union (USSR) there are periodic mass media stories that Alaska was not sold to the United States in the 1867 Alaska Purchase, but only leased for 99 years (= to 1966), or 150 years (= to 2017)—and will be returned to Russia. However, the Alaska P... |
why isn't catherine, dutchess of cambridge called princess catherine? | I believe because she does not have royal blood - she married into royalty. | [
"Catherine was of a very fair complexion, had blue eyes, and had a hair colour that was between reddish-blonde and auburn. In her youth she was described as \"the most beautiful creature in the world\" and that there was \"nothing lacking in her that the most beautiful girl should have\". Thomas More and Lord Herbe... |
Are there horror stories that come from the middle ages? | Thank you for the interesting question! I'll preface this by stating that I focus on the 12th Century in England and France.
Lots of chroniclers included anecdotes that contain supernatural elements, some of which are similar to stories we tell now. However, these were largely reported as prophetical or symbolic rathe... | [
"The setting is shown to be in the Medieval era, with other elements thrown in, often bizarre ones (e.g., yellow-painted taxicabs pulled by rhinoceroses). Stories have included standard Medieval fare, such as armored knights, and some science fiction elements, such as flying saucers.\n",
"Horror Stories was an Am... |
what makes dog years different from human years+ | There's really no such thing as "dog years". It's just a way to give a rough estimate of how old a dog is compared to a human lifespan. Humans live roughly seven times a long as dogs (though it varies widely based on breed), so a dog that is 5 years old has lived roughly the same percentage of its expected lifespan a... | [
"There are two diametrically opposed definitions of the \"dog year\", primarily used to approximate the equivalent age of dogs and other animals with similar life spans. Both are based upon a popular myth regarding the aging of dogs that states that a dog ages seven years in the time it takes a human to age one yea... |
At a cellular level, is there a difference between mammals, birds, fish, amphibians, and reptiles? | If you are talking the contents of a cell, they roughly have the same features \(i.e. organelles, cytoskeleton\). All will have a nucleus with DNA. All will have mitochondria. You would have a hard time distinguishing cells as mentioned by kernco. In fact, an untrained eye would have a difficult time distinguishing... | [
"Birds generally have lower EQ than mammals, but parrots and particularly the corvids show remarkable complex behaviour and high learning ability. Their brains are at the high end of the bird spectrum, but low compared to mammals. Bird cell size is on the other hand generally smaller than that of mammals, which may... |
What was the extent of the Known world in ancient Egypt? | This is my first post, so I hope that I'm doing this correctly :)
I'm going to assume that you are asking from Egypt's point of view as opposed to the entire world.
Due to the fact that my interests primarily lie in New Kingdom Egypt, I'll just answer when it comes to that time period. (Circa mid 1500's BC-1069 BC)
... | [
"From 1560 to 1080 BCE, the Egyptian Empire reached its zenith as the dominant power in the Middle East. When Rome was still a marsh and the Acropolis was an empty rock, Egypt was already one thousand years old. Although the period of the pyramid-builders was long over, Egypt lay on the threshold of its greatest ag... |
why cars don't have built in breathalyzers to prevent drunk driving. | Because it'd be weirdly invasive to try and force people to buy cars with what amounts to a monitoring system and it wouldn't be effective; you can't police everybody full time and make sure nobody tampers with it to deactivate it or give false readings. | [
"Additionally, MADD has proposed that breath alcohol ignition interlock devices should be installed in all new cars. Tom Incantalupo wrote: \"Ultimately, the group said yesterday, it wants so-called alcohol interlock devices factory-installed in all new cars. \"The main reason why people continue to drive drunk tod... |
Was Lenin that bad? | I'd have to be really frustrating and say this isn't really an answerable question. If we were to simplify it and just compare Lenin to Stalin, the thing is that Lenin and Stalin were operating in very different times, under different constraints. We don't know what Lenin would have done if faced with the threat posed ... | [
"Service stated that Lenin could be \"moody and volatile\", and Pipes deemed him to be \"a thoroughgoing misanthrope\", a view rejected by Read, who highlighted many instances in which Lenin displayed kindness, particularly toward children. According to several biographers, Lenin was intolerant of opposition and of... |
What is the efficacy of these alarm clocks which use some sort of head-band scanner (I assume EEG) to select the time to wake you? (example linked to in comments) | The method has been [validated](_URL_1_), however the efficacy of the device to improve sleep [has not been](_URL_0_).
| [
"Many alarm clocks have radio receivers that can be set to start playing at specified times, and are known as \"clock radios\". Some alarm clocks can set multiple alarms. A \"progressive alarm clock\", can have different alarms for different times (see Next-Generation Alarms) and even play music of your choice. Mos... |
Why is blue light the first to get absorbed into the atmosphere through rayleigh scattering, but it penetrates water deeper than other colors? | Really good question!
In terms of scattering, yes, blue light is scattered more easily in water and in air. However, absorption is very different for water and even water vapor.
In water, there is a strong preference for absorption at the lower energy red end of the visible spectrum. The reason for this can be derive... | [
"The strong wavelength dependence of the scattering (~\"λ\") means that shorter (blue) wavelengths are scattered more strongly than longer (red) wavelengths. This results in the indirect blue light coming from all regions of the sky. Rayleigh scattering is a good approximation of the manner in which light scatterin... |
why does radiation spike and roam | What is radiating are tiny radioactive particles. Like dust, they can accumulate in certain places because of natural forces such as wind or rain. In your house or flat, dust usually accumulates in certain places, yes? That happens to radioactive particles too. Sometimes spikes emerge from such spots. What also causes ... | [
"Broadcast radiation is the accumulation of broadcast and multicast traffic on a computer network. Extreme amounts of broadcast traffic constitute a broadcast storm. A broadcast storm can consume sufficient network resources so as to render the network unable to transport normal traffic. A packet that induces such ... |
How would high medieval spearmen handle other infantry armed with swords and shields? | Hey, I know your larp!
First, let's establish some historical baselines. Spear and shield was common in the early middle ages, especially in the 5th and 6th centuries. After that, swords gained ground steadily as metallurgy improved and economic ties across Europe + the emergence of more and more professionalized figh... | [
"The main offensive weapon used was a long and in diameter spear called a \"doru\", or \"dory\". It was held with the right hand, with the left hand holding the hoplite's shield. Soldiers usually held their spears in an underhand position when approaching but once they came into close contact with their opponents, ... |
Why do most insulins advise strongly against mixing with other insulins? What would happen if a mixed injection was taken? | Some insulins can be mixed. Examples are Regular and NPH or an ultra short like Lispro and NPH, which get mixed all the time in hospitals, and even come premixed (Novolin 70/30, Novolog 70/30). The ultra longs are the only ones that I'm aware of that you don't mix (glargine aka Lantus), but as to why I don't know. [Thi... | [
"Several groups of drugs, mostly given by mouth, are effective in type 2, often in combination. The therapeutic combination in type 2 may include insulin, not necessarily because oral agents have failed completely, but in search of a desired combination of effects. The great advantage of injected insulin in type 2 ... |
why can your body stop the bleeding from a small cut over the course of a few minutes, but bruises can continue to develop and worsen over the course of a few days? | A bruise is from thousands of capillaries in the area breaking and releasing a little bit of blood into the surrounding tissue. The breaks in the vessels will clot of just as fast, if not faster than those from a cut. The reason it changes color/intensity over time is that the blood will pool in areas that may be easie... | [
"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... |
why does covid-19 hurt the market? | If China makes a product for the US and the factory shuts down Because of the virus then there are no products being made. Which means people lose money since they can't sell their product. With the stock market you are investing into companies and such. When the company you're investing into halts production their val... | [
"MiR-19 also takes part in inflammatory responses enhancing or repressing pro-inflammatory mediators expression. It positively regulates Toll-like receptor signaling with Dicer1 deletion and miRNA depletion. MiR-19b is an important protagonist in this phenomenon, regulating positively NF-kB activity.\n",
"miR-129... |
the difference between paraphilia and fetish | A paraphilia is something that is harmful to oneself or others and is needed to achieve orgasm. Paraphilias and fetishes are similar, but not every fetish is harmful, and all paraphilias are in some way. These disorders can cause distress or impairment (and those are the only kind recognized in the DSM), and are harmfu... | [
"Separate from fetishes as a paraphilia are garments worn to enhance appearance, such as tight jeans or other eye-catching clothing. The difference is whether, for the person concerned, the clothing is the focus of a sexual fetish, or is merely appreciated and found pleasing.\n",
"In common parlance, the word \"f... |
why would a working class person want to vote for a candidate who favors tax breaks for the wealthy? | As John Steinbeck puts it: « Socialism never took root in America because the poor see themselves not as an exploited proletariat but as temporarily embarrassed millionaires. » | [
"\"We know that elections cannot overcome the massive problems we face. Only our struggles and mobilizations can do that. Nonetheless, by keeping Working Class Party on the ballot, we can give working people a way to express their desire to have a party that represents their own class. And this could lay the ground... |
why are possible gravitational waves at ligo significant? | Stunning confirmation of Einstein's theory of general relativity. Not that other things haven't already been measured, but is another confirmation of a specific prediction, which helps confirm that his theory is correct. Its another stepping stone in the search for understanding gravity and the big bang.
While nowhe... | [
"In 2015, the LIGO project was the first to directly observe gravitational waves using laser interferometers. The LIGO detectors observed gravitational waves from the merger of two stellar-mass black holes, matching predictions of general relativity. These observations demonstrated the existence of binary stellar-m... |
Martin Meredith's "The Fortunes of Africa": A good source on the subject? | It's a decent introduction to the subject of African history, though if you're looking for detail on certain specific civilizations or events, I'd suggest looking elsewhere. It's a legitimately good broad overview of the history of the continent and providing sources for further reading. It does feel a bit Eurocentric ... | [
"African Sources for African History is a book series published by Brill that aims to make available critical editions of indigenous African narrative sources from sub-Saharan Africa. The series aims to expand the sources available to historians of Africa, and to rectify bias that may have been introduced into the ... |
Why is g constant regardless of the mass of an object on a planet, but the mass of the planet does matter? | From Newton's universal law of gravity, we have
F=GMm/r^2
where we can say M is the Earth's mass, and m is the object's mass.
Newton's 2nd law is:
a = F/mass
For the acceleration of the object by the Earth, we set mass=m and F=GMm/r^(2), which gives us a=GM/r^(2) - it depends on the Earth's mass, but not on the ob... | [
"The value of \"G\" is difficult to measure and is only known with limited accuracy in SI units (\"see\" Cavendish experiment). The value of \"G\" times the mass of an object, called the standard gravitational parameter, is known for the Sun and several planets to much higher accuracy than \"G\" alone. As a result,... |
How do you know the limit of something as x approaches infinity? | > To take the derivative, it seems as if you would need to have infinte precision? It's seems as if though the whole of calculus is based around this infinite precision thing. Integrals use rectangles to approximate the area under a function right? And then you increase the numbers of rectangles all the way to infinit... | [
"which is either 0, if \"d\" = 0, or gets arbitrarily small, when \"n\" tends to infinity. According to the definition of a limit, \"x\" is the limit of [\"x\"] when \"n\" tends to infinity. This is written as formula_7 or\n",
"That is, the limit as \"x\" goes to 8 from above is a sideways 8 or the infinity sign,... |
Animals, e.g. (wild) cats, have loads of anonymous sex and know nothing about protection or medicine. Why aren't they decimated by cat aids? | FIV is much less deadly than HIV.
Cats have been dealing with FIV for a long time, somewhere in the 10's of millions of years. Overtime they have built up some resistance; you see the same thing happening in human populations that are under intense selection from HIV. CCR5 delta 32 is a famous mutation that provides ... | [
"Cats can be infected or infested with viruses, bacteria, fungus, protozoans, arthropods or worms that can transmit diseases to humans. In some cases, the cat exhibits no symptoms of the disease, However, the same disease can then become evident in a human. The likelihood that a person will become diseased depends ... |
why aren't animals like gorillas who are very strong released back to the wild? | That isn't why.
Sure, some of them might be half tame and too comfortable being around humans, making it easier to kill them or just make them a pest.
But they lack the upbringing thier parents would give them. They dont know how to act around their wild relatives. And they havent been passed down the knowledge of ... | [
"A study published in 2007 in the \"American Journal of Primatology\" announced the discovery of the subspecies fighting back against possible threats from humans. They \"found several instances of gorillas throwing sticks and clumps of grass\". This is unusual. When encountered by humans, gorillas usually flee and... |
why do we have to cook things with a low flame for a long time. why not a high flame for a short amount of time? | Large flame means high temperature. High temperature means the outer layer of food might burn before the inside has been heated up.
Low temperature takes more time, but gives you much more even cooking. | [
"The low temperature of slow-cooking makes it almost impossible to burn even food that has been cooked too long. However, some meats and most vegetables become nearly tasteless or \"raggy\" if over-cooked.\n",
"Because of the longer cooking time, there is greater danger with slow cookers of having an extended pow... |
why does the mixing of alcoholic beverages seemingly get you drunker quicker/why is it seen as such a bad thing? | It doesn't really, it's just easy to physically drink more when you are mixing it up. It seems weird to drink your 5th vodka but if you have drank a bunch of different stuff you don't notice you have drank so much. Food is the same way, People will notice they are eating a ton if there is just one food out, but if ther... | [
"Mixing alcohol with normal soft drinks, rather than diet drinks delays the dizzying effects of alcohol because the sugary mixture slows the emptying of the stomach, so that drunkenness occurs less rapidly.\n",
"The effect is a consequence of the fact that alcohol has a lower surface tension than water. If alcoho... |
- why do public restrooms have automatic soap dispensers if you will wash your hands directly after applying the soap? | Perceived convince and portion control.
A huge problem for businesses is users who take way more of bathroom goods that they actually would need, wasting goods and leading to more frequent empty situations.
Automatic dispensers usually have some delay between dispensing portions of a product, making it more dif... | [
"Automatic soap dispensers (also known as touchless or no-touch soap dispensers) dispense a controlled amount of soap solution (or a similar liquid such as a hand sanitizer). They are often used in conjunction with automatic faucets in public restrooms. They function to conserve the amount of soap used and stem inf... |
why two unrelated movies, songs or books can have the same title but video game titles are vigorously protected? | Because in most cases, a game's title is the strongest and most valuable part of its brand, which is often not true for books and especially music.
In books and music, it is the artist/author which is the stronger part of the brand. For example, the album name "Midnight Love" may not mean much to you, but "Midnight Lo... | [
"Some games could not be included due to licensing (e.g. \"Tron, Lock 'N' Chase, BurgerTime, Loco-Motion, Mission-X, Masters of the Universe, Pac-Man, Dig Dug, Diner, Pole Position, Commando\"). Others such as \" and \" are working prototype versions to avoid trademarked names. Licenses such as Major League Basebal... |
why do so many books have two to three blank pages at the start? | Imagine I took a standard piece of paper. I could fold it into 4 pieces, then cut the top and bottom a bit, staple it, and have a small book.
This is called a signature. They can be as small as 4 pages, or much larger. A book is typically made up of several signatures.
The result is, I can take two 4 page signatur... | [
"The book is laid out in twelve columns from right to left, each one representing a \"page\". Much of the first three columns are missing, and it is not known where the book begins. Closer to the end of the book the text is almost complete (there is a strip missing that runs the entire length of the book). By the e... |
how do tv commercials that mention “amazon alexa” prevent the activation of devices? | I don't have an Alexa, but I literally JUST watched [this video](_URL_0_) before coming to this sub, which mentioned that Alexa doesn't differentiate between your voice and anyone else's. So it can be activated by your kid, someone on the TV, or even a pet parrot (there are youtube vids of parrots activating Alexas, an... | [
"In July 2018, Google banned additional categories of apps, including those that perform cryptocurrency mining on-device, apps that \"facilitate the sale of explosives, firearms, ammunition, or certain firearms accessories\", are only used to present ads, contain adult content but are aimed towards children, \"mult... |
does the black hole at the center of the milky way have a diameter? | It's the singularity that has no diameter. Yes, black holes have event horizons accretion disks which can be measured up to the singularity. | [
"Donald Lynden-Bell and Martin Rees hypothesized in 1971 that the center of the Milky Way galaxy would contain a massive black hole. Sagittarius A* was discovered and named on February 13 and 15, 1974, by astronomers Bruce Balick and Robert Brown using the Green Bank Interferometer of the National Radio Astronomy O... |
Was the United States the first country to have money called "dollar"? Where did the name come from? Why was it chosen? Why have so many countries adopted the name? | No, the word "dollar" is quite a bit older than the US government's unit of currency. It is an anglicised form of "thaler", which was the name given to coins first minted in 1519 from silver mined in Joachimsthal in Bohemia. Thaler is a shortened form of the term by which the coin was originally known: Joachimsthaler.
... | [
"The history of the United States Dollar refers to more than 240 years since the Continental Congress of the United States authorized the issuance of Continental Currency in 1775. On April 2, 1792, the United States Congress created the United States dollar as the country's standard unit of money. The term \"dollar... |
what is fcc rules part 15, and why must my devices "accept all interference including interference that may cause undesired operation"? | electricity is just magnetism seen from a different point of view, and magnetism travels through the air. So any electric device creates (induces) electric current in other nearby electric devices.
These FCC rules say that a product can't break because of other devices' electro-magnetic field ("must accept...") and s... | [
"The FCC is also responsible for permitting transmitters, to prevent interference between stations from obscuring each other's signals. Denial of the right to transmit could be considered censorship. Restrictions on low-power broadcasting stations have been particularly controversial, and the subject of legislation... |
How does the cold war 'communism' scare compare to today's 'war on terror'? | *Nothing is so irretrievably lost to a society as the sense of fear it felt about a grave danger that was subsequently coped with.* -- George Will.
Reddit's demographic skews young, and people here don't often have the experience to be able to compare the modern "war on terror" to the "war on communism." The truth of ... | [
"The end of the Cold War and the fall of the Soviet Union have been credited with leading to a marked decrease in this form of terrorism. Brian Crozier, founder and director of the Institute for the Study of Conflict, has said that communism was the primary source of both state-sponsored and non-state terrorism.\n"... |
Do frozen methane clouds on Titan retain a static shape? | The is a big difference between a solid chunk of methane versus a thin accumulation of crystalline droplets. On Earth, some clouds are made of water droplets and others are made of ice. On Titan, the ice methane clouds would behave similarly to the ice clouds on Earth or Mars. Here's some more info:
_URL_0_
The ice ... | [
"Titan's clouds, probably composed of methane, ethane or other simple organics, are scattered and variable, punctuating the overall haze. The findings of the \"Huygens\" probe indicate that Titan's atmosphere periodically rains liquid methane and other organic compounds onto its surface.\n",
"In September 2006, \... |
Did the illuminati have a role in the french revolution? (yes, this is serious) | The Illuminati, as Augustin Barruel describes it, is fictional. He ties together branches of enlightenment philosophy with various secret societies and claims that it's all one big group. [This link](_URL_0_) has excerpts from an essay that debunks specific claims.
Most of the supposed Illuminati connections are the ... | [
"In the late 18th century, reactionary conspiracy theorists, such as Scottish physicist John Robison and French Jesuit priest Augustin Barruel, began speculating that the Illuminati had survived their suppression and become the masterminds behind the French Revolution and the Reign of Terror. The Illuminati were ac... |
What keeps Jupiter, a gas giant, from collapsing under its own gravity and becoming a dense solid? | Hydrostatic equilibrium is what you want to look into. It's what keeps big round things round, from planets to stars.
In Jupiter's case, the gas at the center is hot from the extreme pressure exerted by gravity. The heat and pressure causes the gas to rise, so there's an equilibrium between gravity pulling down and th... | [
"A cold hydrogen-rich gas giant more massive than Jupiter but less than about () will only be slightly larger in volume than Jupiter. For masses above , gravity will cause the planet to shrink (see degenerate matter).\n",
"Jupiter is primarily composed of hydrogen with a quarter of its mass being helium, though h... |
When I look at a projector image on a wall and move my eyes from one end of the image to the other fast, I can see individual RGB lines (a few cm wide). Why? | not really a science based question, but your projector is DLP (digital light processor) based, meaning it has a chip where each pixel is a microscopic little mirror on a tiny hinge, the projector reflects off the chip,
each mirror switches on/off by tilting off axis (a tilted mirror cant reflect the pixel) these mir... | [
"The entire scene, including the window, can be moved backwards or forwards in depth, by horizontally sliding the left and right eye views relative to each other. Moving either or both images away from the center will bring the whole scene away from the viewer, whereas moving either or both images toward the center... |
Red-shift, Blue Shift and Cosmic Expansion. If the universe has been expanding since the Big Bang, and if the further we look out into space the further back in time we are seeing, shouldn't objects appear to be moving closer to each other and to us and thus be blue shifted, NOT red-shifted? | The reason we're "looking back in time" is that light just reaching us from the objects at which we're looking left them a long, long time ago. In the meantime, this light has been traversing expanding space, which has acted to increase it's wavelength—i.e., to redshift it. | [
"Around 1930, Edwin Hubble discovered that light from remote galaxies was redshifted; the more remote, the more shifted. This was quickly interpreted as meaning galaxies were receding from earth. If earth is not in some special, privileged, central position in the universe, then it would mean all galaxies are movin... |
why can't we feel our bodies gaining weight, growing taller, etc.? | It happens really slowly. REALLLLLY SLOWLY. | [
"In regard to adipose tissue increases, a person generally gains weight by increasing food consumption, becoming physically inactive, or both. When energy intake exceeds energy expenditure (when the body is in positive energy balance), the body can store the excess energy as fat. However, the physiology of weight g... |
how do people afford to live in venezuela if a monthly salary is 3$? | It's worth pointing out that Venezuelans can*not* afford to live, if by "live" you mean "afford to pay for food and necessities". As of last year, [Venezuelans lost an average of 19 pounds and 93% said they did not have enough money to pay for food](_URL_0_). Unfortunately the situation has worsened since then. I can't... | [
"Venezuelans and activists harassed government officials and their families who enjoyed luxurious lifestyles compared to Venezuelan citizens. The top income of a Venezuelan official would be approximately $700 per year. Despite this, families of Bolivarian officials live abroad and even attend foreign universities.... |
how astronomers can find a galaxy 30 billion light-years away, twice as far as the universe is old. | Space is expanding. The galaxy in question was actually much closer when the photons we're now receiving left it. | [
"BULLET::::- Astronomers report that the most distant known galaxy, UDFj-39546284, is now estimated to be even further away than previously believed. The galaxy, which is estimated to have formed around \"380 million years\" after the Big Bang (about 13.75 billion years ago), is approximately 13.37 billion light ye... |
How many Germans actually supported Hitler in his endeavors? | Define support.
Actively endorsing Nazi ideology and joining the party or security forces? Chanting slogans along with everyone else at rallies? Don't really care but works at a government ran munition plan anyway? Don't like the Nazis but never protected any Jews that he was friends with? | [
"Haffner argues that on gaining office in 1933, Hitler achieved many 'miracles' in economic and military policy.. 90% of Germans approved. Had he died in 1938, he would have been remembered as 'one of the greatest Germans ever'. Few people noticed that he had dismantled the state and concealed the resultant chaos. ... |
do photons age? | Photons do not experience time, so they do not age as we understand it. They do 'die' whenever they are absorbed. Every photon emitted by your monitor 'dies' in your retina (converted to electrical impulses) so you can read this answer. | [
"Recent evidence suggests that aging is also related to the loss of myelinated nerve fiber length and the mass of white matter, with individuals losing approximately 45% of total nerve fiber length as they age.\n",
"Age plays a role in brightness, as a contributing factor is the observer's pupil. With age the pup... |
if gravity has a quantum manifestation of itself (gravitons), how does anti-matter relate to it? would there be some kind of anti-graviton particle? | The expectation is that gravitons are their own antiparticle, similar to how photons are their own antiparticle. So no, there probably isn't another such particle unless we have things very wrong. | [
"The first non-classical, non-quantum physical principles underlying a matter-antimatter gravitational repulsion have been published by Marcoen Cabbolet. He introduces the Elementary Process Theory, which uses a new language for physics, i.e. a new mathematical formalism and new physical concepts, and which is inco... |
How does Aloe Vera help with sunburns? | Aloin Suppresses Lipopolysaccharide-Induced Inflammatory Response and Apoptosis by Inhibiting the Activation of NF-κB
_URL_0_
NF-kB is the major inflammatory pathway in humans and signals immune response that inhibit healing in an attempt to kill off what is perceived by the immune system as pathogenic invasion. By s... | [
"Home treatments that may help the discomfort include using cool and wet cloths on the sunburned areas. Applying soothing lotions that contain aloe vera to the sunburn areas was supported by multiple studies, though others have found aloe vera to have no effect. Aloe vera has no ability to protect people from sunbu... |
why do businesses build skyscrapers in cities when it would be much cheaper to build their offices further out where land is cheaper? | There are a lot of advantages to having an office in a central downtown area like this.
1) Free advertising
2) Good public transit/ease of access for employees
3) You can rent out unused floors and are likely to fill them as the space is in higher demand
4) Skyscrapers can be more efficient/more compact than wid... | [
"[not] because [the skyscrapers] are desirable, healthy, beautiful, and reasonable from the perspective of urban planning but because they are theatrical, romantic, unreasonable, and generally harmful, and because it is part of the money-making activities of a metropolis, in what is literally the world's most inter... |
how can you know when you've had enough sleep? if you can fall back asleep, are you not done? | *Enough* sleep is different for everyone. The common number is 8 hours of sleep a night - however this is based on statistical data. Other studies show that many people can function on less sleep with no side effects. You can know when you've had enough sleep when you do not have general sleep deprivation symptioms suc... | [
"The Maintenance of Wakefulness Test (MWT) measures a person’s ability to stay awake for a certain period of time, essentially measuring the time one can stay awake during the day. The test isolates a person from factors that can influence sleep such as temperature, light, and noise. Furthermore, the patient is als... |
why are crossfitters looked down upon by the bodybuilding community? | Crossfit gets a bad rap because of a few different reasons
1) Their teachers only require a weekend certification course, and as such oftentimes give their students subpar lessons on form. This leads to a high rate of injury, which increases exponentially with the WOD being such a variable, with often strange biomecha... | [
"CrossFit is promoted as both a physical exercise philosophy and a competitive fitness sport, incorporating elements from high-intensity interval training, Olympic weightlifting, plyometrics, powerlifting, gymnastics, girevoy sport, calisthenics, strongman, and other exercises. It is practiced by members of over 13... |
why do we ask for autographs when we meet famous people? | To remember the encounter and to prove to people that we really met them. And to an extent, because the autograph might be worth something one day. | [
"Some celebrities still enjoy signing autographs for free for fans. Many people who stand outside premieres, asking for autographs are actually professional autograph traders, who make their living or supplement their income by selling them for full profit, rather than keeping them as a personal souvenir. This is o... |
why was the concept of the month developed/accepted? why don't we count the date as "day 275" of the year, for example? | The concept of the month was based on the cycles of the moon, which last about 29 days. The English word "month" comes from the word "moon". | [
"During the period between 1582, when the first countries adopted the Gregorian calendar, and 1923, when the last European country adopted it, it was often necessary to indicate the date of some event in both the Julian calendar and in the Gregorian calendar, for example, \"10/21 February 1750/51\", where the dual ... |
In a constant environment at 0 degrees Celsius, will water molecules freeze or melt? | In a water/ice mixture, molecules are both 'sticking' to the ice if they have too little energy to overcome the attraction of the water molecules in the ice, and liberating themselves from it if they have enough energy to break free.
At 0 C both those things occurs at the same rate, so whichever amount of water/ice y... | [
"There are phenomena like supercooling, in which the water is cooled below its freezing point, but the water remains liquid, if there are too few defects to seed crystallization. One can therefore observe a delay until the water adjusts to the new, below-freezing temperature. Supercooled liquid water must become ic... |
Is there evidence that the founders included cannons and bombs in defending the 2nd Amendment? | The 2nd Amendement is not terribly concerned with individual ownership of weaponry, it's concerned with civilian oversight of the military. It is impossible to separate the writing of the 2nd Amendment from the militia laws, and the political beliefs that surrounded them.
In brief: the framers by and large (with major... | [
"Modern scholars Thomas B. McAffee and Michael J. Quinlan have stated that James Madison \"did not invent the right to keep and bear arms when he drafted the Second Amendment; the right was pre-existing at both common law and in the early state constitutions.\" In contrast, historian Jack Rakove suggests that Madis... |
If DNA stores information of how to make proteins, where is the information for what to do with the proteins stored? | its horribly complicated and we dont know completely yet. I'll keep to the basics. also have to be careful by what you think of as information
first off, DNA codes for more than just proteins, it also has regulatory sequences in it (promoters, inhibitors, protein binding regions).
moreover, there is another layer of ... | [
"In order to make a protein, genetic information in DNA is copied (transcribed) into messenger RNA (mRNA) in the nucleus and then exported into the cytoplasm, where it is translated into a protein. Much of Izaurralde's early career focused on elucidating how this export occurs at a molecular level.\n",
"If the ge... |
If heavy elements are formed due to supernovae, how come we have so much of them on Earth if supernovae are relatively rare events? | The elements which only can be formed by supernovae, elements heavier than Nickel, together account for about 0.05 ppm (parts per million) of the matter in the universe - for every ton (1000 kg) of matter, there is 0.05 g of heavy elements. That is not a lot.
However, there's more of them here on Earth. How much more?... | [
"Supernovae can result from the death of an extremely massive star, many times heavier than the Sun. At the end of the life of this massive star, a non-fusible iron core is formed from fusion ashes. This iron core is pushed towards the Chandrasekhar limit till it surpasses it and therefore collapses.\n",
"Theoret... |
Was China trying to kill the 14th Dalai Lama in 1959? Or were they just generally going for Tibet? | Hi there, sorry I'm late.
Your question seems to imply a misunderstanding of the timeline.
The People's Liberation Army launched their invasion/liberation of Tibet in October 1950. Tibet was then led under the name of Tenzin Gyatso, the Dalai Lama, who was only fourteen years old at the time. A Regency council func... | [
"On April 18, in an interview to Canadian journalists, it was reported that the Dalai Lama said that since the beginning of the demonstrations in Tibet at least 400 people had been killed and thousands of others arrested.\n",
"Upon his return to Tibet, the Dalai Lama learns of more horrors perpetrated against his... |
if plants produce oxygen, then is breathing in a garden "easier" or better for you than breathing inside a building? | You don't use a lot of the oxygen you inhale in either case. We generally inhale about 21% oxygen from the atmosphere. The air we exhale is about 16% oxygen. | [
"As aerobic respiration decreases, the plants become oxygen deficient, since the roots are unable to produce enough oxygen in the reduced soil conditions. Decreased oxygen uptake can also decrease plant productivity.\n",
"Clean air supplies oxygen which is an excellent purifier for plants and the aeroponic enviro... |
what exactly is a "double-blind" study? | The tester and the subject are both 'blind'. If you're doing a cola taste test double blind then the person presenting the drinks and recording the data doesn't know which is Pepsi and which is Coke, and neither does the person being tested. | [
"A double-blind study with only objective measures is less likely to be biased to support a given conclusion. However, the researchers or the sponsors still have opportunities to skew the results by discarding or ignoring undesirable data, qualitatively characterizing the results, and ultimately deciding whether to... |
Is water pressure the same regardless of the volume of water? | Liquid pressure (P) is dependent upon three things:
1) density (p)
2) gravity (g)
3) height aka depth (h)
Represent by the equation P = pgh.
So the pressures would be the exact same in your scenario.
Although if you're talking about TOTAL pressure you have to include the pressure if the atmosphere as well, which wo... | [
"It is important to recognize that the pressure does not depend on the \"amount\" of liquid present. Volume is not the important factor – depth is. The average water pressure acting against a dam depends on the average depth of the water and not on the volume of water held back. For example, a wide but shallow lake... |
Is there a limit to the amount of languages a person can learn? | The trivial answer is "yes," because we know that there must be a limit: We have finite brainpower, finite time, and there are a finite number of languages.
Giving a more meaningful answer - one giving a number or range - is unfortunately impossible, for at couple of reasons.
The first is that it's very hard to quan... | [
"BULLET::::3. \"The rules of language make up only a small portion of our language competence\": Acquisition does not provide 100% language competence. There is often a small portion of grammar, punctuation, and spelling that even the most proficient native speakers may not acquire. While it is important to learn t... |
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