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Why does a star's fusion process proceed in the particular order of elements that it does, rather than simply marching up the periodic table from simpler to more complex elements? | answer for why it skips from helium to carbon:
The basic issue is that there is no stable isotope with either 5 or 8 nucleons, which is how many nucleons you'd have if you added hydrogen-1 with helium-4 or just merged two helium-4 nuclei.
Lithium 5 is so unstable that I can't even find it in any list of lithium isoto... | [
"As the fraction of hydrogen remaining in the core of a main sequence star decreases, the core temperature increases and so the rate of fusion increases. This causes stars to evolve slowly to higher luminosities as they age and broadens the main sequence band in the Hertzsprung–Russell diagram.\n",
"When fusion o... |
why isn't it possible for people who've died of hypothermia to "defrost" and have their heart restarted after their bodies have been "warmed up"? | The water in our bodies freezes into crystals, and the crystals literally tear our bodies (cells) apart like tiny knives. | [
"Ventricular tachycardia represents a series of irregular heartbeats that may cause the heart to completely shut down resulting in cessation of oxygen flow. Further, irregular heartbeats may result in formation of blood clots, thus leading to oxygen deprivation to all organs.\n",
"A notable exception is cardiac a... |
Are there any in-depth texts that shed light on how gourmet food tasted long ago? For example, recipe books pertaining to what English royalty ate in the 9th century, or Roman emperors ate in Byzantium? | I can't anwser for cuisine in the Antiquity, but I can give you some pointer in medieval cuisine, specifically for french cuisine in the XIVe century (wich is already "a long time ago").
& nbsp;
We have two main sources for that : *Le Viandier de Taillevent* (roughly translated : "Taillevent's Meatbook"), redacted b... | [
"The Museum of English Rural Life at the University of Reading curates the Dorothy Hartley collection. It cites the Oxford Dictionary of National Biography's entry on Hartley, calling \"Food in England\" \"Arguably her best work, and the one for which she will be remembered\". It calls the book \"as full of magic a... |
- why is the earliest a computer can go back is december 31st, 1969? | this isnt relevant but i found it on the internet -
*The date that most computer clocks are set to is the beginning of the "VAX-Epoch" which was the first millisecond of Jan 1, 1970, which is stored as the number "1".
And it is ticked off in a computer's clock in milleseconds from that time.
* | [
"On what \"Time\" called \"D-Day for the Home Computer\", and others described as \"the biggest fanfare in the history of computers\", IBM announced the PCjr on November 1, 1983, at its New York City headquarters with an enormous amount of advance publicity, including live news-broadcast coverage of the event. \"Co... |
Question about the Thugee.
Did the assassin cult realy exist, or was it an invention of the British empire's propaganda? | This is a controversial question that doesn't have a simple answer. What answers historians give have a lot to do with their own understandings of colonialism and since answers to those questions rely on still contentious theoretical debates there will be a lot of disagreement.
There are a range of views amongst hist... | [
"Martine van Woerkens of École Pratique des Hautes Études writes that evidence for a Thug cult in the 19th century was the product of \"colonial imaginings\", arising from British fear of the little-known interior of India, as well as limited understanding of the religious and social practices of its inhabitants.\n... |
why do the state boarders on the western portion of the united states have straight lines/ boxy shapes while the eastern boarders seem to be random and chaotic? | Simple answer: The eastern borders of the US were largely determined by geographic landmarks (especially rivers). The Western borders were man-made based on longitude and latitude.
| [
"Some states are then divided into regions, districts, or areas. These are often governed by an elected official who serves on the State Officer Team. Just like the national regional executive boards, there are small-scale boards in most regions, districts, and/or areas in most states.\n",
"The States have been g... |
What is the easiest way to conceptualize the expansion of the universe if it has no center? | I find it easiest to imagine a bunch of dots drawn on a deflated balloon. If you inflate the balloon, the dots all move apart from each other. But as far as each dot is concerned, its not moving, its everything else that's moving away. So it feels like its at the center, when we can see from a distance that its no diff... | [
"Hubble's Law suggested that the universe was expanding, contradicting the cosmological principle whereby the universe, when viewed on sufficiently large distance scales, has no preferred directions or preferred places. Hubble's idea allowed for two opposing hypotheses to be suggested. One was Lemaître's Big Bang, ... |
Why did the Byzantines prefer mosaics to sculpture in the previous unified Roman Empire? | Does iconoclasm have to do with it? | [
"Mosaic was a common form of decoration throughout the Roman Empire and because of its durability was usually applied to floors, where it was at first executed in pebbles or small marble tiles. During the Early Christian period glass tiles were used extensively for wall and vault decorations, the vault of the Mauso... |
I just heard on NPR that 56 million years ago, the earth was 11 degrees warmer. How do they know this? | It is not "known." It's hypothesized based on indirect observations called proxies.
One of the best and most commonly used proxies for estimating paleotemperatures is the abundance of heavy stable isotopes of common elements like Oxygen. Two stable isotopes of Oxygen have atomic masses 16 and 18 and because of their d... | [
"In 2007 the National Oceanic and Atmospheric Administration stated that the \"U.S. and global annual temperatures are now approximately 1.0°F warmer than at the start of the 20th century, and the rate of warming has accelerated over the past 30 years, increasing globally since the mid-1970s at a rate approximately... |
if you were a few mph below the sound barrier, then made a sonic boom, then slightly slowed down then sped up again, would it constantly make multiple sonic booms? | The boom isn't something that happens once as you break the sound barrier. As you're traveling faster than sound you are "booming" continously. It seems like a momentary boom to an observer on the ground, because the boom travels with you. | [
"The sound barrier or sonic barrier is the sudden increase in aerodynamic drag and other undesirable effects experienced by an aircraft or other object when it approaches the speed of sound. When aircraft first began to be able to reach close to the speed of sound, these effects were seen as constituting a barrier ... |
How good or reliable is Winston Churchill's biography of his ancestor, the Duke of Marlborough? | Historians are generally hesitant to call books by laypeople "good history." I haven't read this book, but it's probably a great way to understand Churchill, especially if you read it alongside some scholarship on him. That said, if you find it interesting, read it! He certainly put a great deal of effort into the, wha... | [
"The Churchills is a 2012 three-part documentary written and presented by David Starkey that tells the story of two great war leaders Winston Churchill and his ancestor John Churchill, 1st Duke of Marlborough and the striking similarities in their lives.\n",
"Although Churchill was not a trained historian, the in... |
how will giving free food to the african people make things worse than they are? | Not a foremost expert, but I know the basic issue. It's a twofold problem. Nearly all of the rudimentary African governments have a disgusting level of corruption and will take take aid money/food/whatever and say they're giving it to their people when they're hoarding it for themselves. Throw different tribes/ethnic g... | [
"This has resulted in less food available for human consumption, especially in developing and least developed countries, where a family's daily allowances for food purchases are extremely limited. The crisis can be seen, in a sense, to dichotomize rich and poor nations, since, for example, filling a tank of an aver... |
what are whiteheads/blackheads actually made out of? | They are made out of sebum. Sebum is a substance you secrete in your skin from special glands. If there is too much and it gets trapped in the gland duct, it builds up.
The reason you secrete the sebum in the first place is to lubricate your skin. | [
"The holotype worker is long with an head and a Weber's length of . Much of the body is the same coloration as the surrounding amber, while the lower half of the propodeum and underside of the gaster are a brown to black tone. Additionally the undersides of the coxae plus the upper halves of the tibiae are brown to... |
Question about resistance heating | I'm sure you could vary the resistance via doping in a suitable semiconductor substrate, but you'll have a devil of a time stopping the element from reaching thermal equilibrium when you run current through it. The substrate is going to conduct a fair amount of heat and equalize out the temperature fairly quickly if l... | [
"Resistors (and other elements with resistance) oppose the flow of electric current; therefore, electrical energy is required to push current through the resistance. This electrical energy is dissipated, heating the resistor in the process. This is called \"Joule heating\" (after James Prescott Joule), also called ... |
how does the mpaa work? | The MPAA has their own analysts and consultants who rate the movies based on the guidelines that they set. It should also be noted that rating by the MPAA is voluntary, they only rate the movies that are submitted to them by the film studios that make them. There is no law that requires them to do so, and the rating ca... | [
"The Motion Picture Association of America (MPAA) is an American trade association representing the five major film studios of the United States, as well as the video streaming service Netflix. Founded in 1922 as the Motion Picture Producers and Distributors of America (MPPDA), its original goal was to ensure the v... |
How was Britain’s resilience in the Battle Of Britain viewed around the world at the time? | Garry Campion's *The Good Fight: Battle of Britain Propaganda and the Few* looks at coverage of the Battle, with the United States being the primary focus from an international perspective. There was a wide perception, after the German invasion of France and British withdrawal from Dunkirk, that Britain could not hold ... | [
"Britain's total mobilisation during this period proved to be successful in winning the war, by maintaining strong support from public opinion. The war was a \"people's war\" that enlarged democratic aspirations and produced promises of a postwar welfare state.\n",
"Britain's total mobilisation during this period... |
How does CMB translate to the temperature of space? | The micropascal is a unit of pressure, not temperature.
The cosmic microwave background is an example of what's called blackbody radiation. A blackbody of a given temperature has a characteristic spectrum (the relative amount of power at each wavelength), a spectrum that depends on the temperature. In the early univ... | [
"The temperature of outer space is measured in terms of the kinetic activity of the gas, as it is on Earth. However, the radiation of outer space has a different temperature than the kinetic temperature of the gas, meaning that the gas and radiation are not in thermodynamic equilibrium. All of the observable univer... |
Is it true that homo-/bisexuality was normal/tollerated in islamic countries till 19th century? | Check out this thread from 9 months ago: [What lead to the Ottoman Empire decriminalizing homosexuality in 1858? Was there a lot of opposition and controversy around this?](_URL_0_)
/u/PaxOttomanica /u/gamegyro56 /u/thevarsoviana and /u/Groib provide a ton of interesting info in there. | [
"In the centuries after the advent of Islam in the 7th century in Arabia, religious doctrines against homosexuality were likely trafficked by Arab and Persian traders the Indian oceanic coastline, and later the Omani and Portuguese settlers along the coastline up until the 19th century. With the arrival of European... |
How did Harald Hadrada die? | The source on that is the Saga of Harald Harðráða in _Heimskringla_, a work written by the Icelander Snorri Sturluson around 1230 or so, in other words at least a cenury and a half. The [text](_URL_0_) says, in part 96:
> Haraldr konungr Sigurðarson var lostinn öru í óstinn; þat var hans banasár (King Harald Sigurd... | [
"As a consequence of Harald's army having lost to the Germans at the Danevirke in 974, he no longer had control of Norway, and Germans settled back into the border area between Scandinavia and Germany. They were driven out of Denmark in 983 by an alliance of Obodrite soldiers and troops loyal to Harald, but soon af... |
Is there no cultural legacy of the Mongol Empire in the Western world? | Does your country have compasses, printing presses, and gunpowder? Because they came to Europe while the Mongols were in power over the silk route. | [
"The Mongol Empire — at its height the largest contiguous empire in history — had a lasting impact, unifying large regions. Some of these (such as eastern and western Russia and the western parts of China) remain unified today. Mongols might have been assimilated into local populations after the fall of the empire,... |
how is china 'blocking' vpns? | VPN have very obvious encrypted traffic. They connect on well defined ports and well defined protocols. Block those ports, block those protocols and you'll only be left with finding homebrew encryptions | [
"Chinese Internet users have several ways to circumvent censorship. Netizens generally rely on virtual private networks (VPNs) to access blocked websites and messaging apps. However, in July 2017, the Chinese government required telecommunications carriers including China Mobile, China Unicom, and China Telecom to ... |
Language in Ireland | Irish was the majority mother tongue in Ireland up until the 1800s. There's a few reasons why English was becoming more widely spoken, in brief:
* **British education**: The 'National Schools' instituted in the early 19th century by the British government, who ordered that English only was to be taught right up until ... | [
"The two official languages of the Republic of Ireland are Irish and [[Hiberno-English|English]]. Each language has produced a noteworthy literature. Irish, though now only the language of a minority, was the vernacular of the Irish people for over two thousand years and was possibly introduced during the [[Iron Ag... |
During the American Civil War, how likely was it that Britain and France would have intervened on the side of the C.S.A. | It's not very likely that either France or Britain would have actually fought the Union army along side the Confederacy even if the CSA had won at Antietam. France was in no position to be fighting a war in the US at the time and the British imported a large about of goods from both northern and southern states. Great ... | [
"During the American Civil War both nations remained neutral. France came close to entering on the side of the Confederate States of America. The cutoff of cotton shipments caused economic depression in the textile industry, resulting in widespread unemployment and suffering among workers, and support for an interv... |
why does lava/ molten metal glow? | Everything glows, depending on its temperature.
Most things at everyday temperature glow in the infrared range, below what humans can see. But when things like metal or lava or fire or stars get hot enough, they glow in a range of wavelengths we can see. | [
"Due to this unusual composition, the lava is erupted at relatively low temperatures (approximately 500-600 °C). This temperature is so low that the molten lava appears black in sunlight, rather than having the red glow common to most lavas. It is also much more fluid than silicate lavas.\n",
"The molten rock, wi... |
so what does it mean for the country of mexico, or america for that matter, now that el chapo has been arrested? | When the most famous criminal in Mexico either can't be arrested, or will escape from prison (as El Chapo has done twice) even if he is arrested, this suggests that law enforcement is ineffective and that the criminal underworld has become more powerful than the government. So it is reassuring that El Chapo is once ag... | [
"In September 2007, Mexican President Calderón harshly criticized the United States government for the crackdown on illegal immigrants, saying it has led to the persecution of immigrant workers without visas. \"I have said that Mexico does not stop at its border, that wherever there is a Mexican, there is Mexico\",... |
the economics of cemeteries | I can't say this is true in 100% of cases but most cemeteries are managed by churches which makes them free of taxes. The only real expense is landscaping (very very few cemeteries have any security beyond maybe a fence) which is covered by the regular donations the church collects from those who attend.
Typically th... | [
"The cost of building a garden/rural cemetery often meant that only the wealthy could afford burial there. Subsequently, garden/rural cemeteries often feature above-ground monuments and memorials, mausoleums, and columbaria. The excessive filling of rural/garden cemeteries with elaborate above-ground memorials, man... |
Could the Anasazi have migrated south and become the Aztecas? | This idea had been kicked around in the past, just as a similar idea had been kicked around of the Mound Builders in the east. Both have been rejected by the archaeological community.
The Anasazi are one of four major archaeological cultures that contributed the modern nations of the American Southwest--the others be... | [
"Nahua peoples descended from Chichimec peoples who migrated to central Mexico from the north in the early 13th century. The migration story of the Mexica is similar to those of other polities in central Mexico, with supernatural sites, individuals, and events, joining earthly and divine history as they sought poli... |
I shined a Green laser through oil and it changed color (Link to pictures in text)why? | What you are seeing is a process called [fluorescence.](_URL_0_) Olive oil contains a bunch of organic molecules such as phenols that can absorb the green laser light and re-emit red light. It is this fluorescence that you are seeing when looking to the side of the beam. | [
"Within the ethylene industry, \"Red oil\" is an organic contaminant frequently encountered in caustic towers. The \"red oil\" is an organic polymer that forms from the aldol condensation of acetaldehyde in sodium hydroxide solution. Initially, the acetaldehyde forms a light floating yellow oil. Quickly this will c... |
can a person be vice president without being chosen by the president? | Technically, yes although in practice, it's very unlikely. While a presidential candidate chooses his running mate (who he wants his vice president to be), the Electoral College actually votes for the Vice President separately from the President, so in theory, they could elect someone other than President's running mat... | [
"The vice president of the United States (informally referred to as VP, or veep) is the second-highest officer in the executive branch of the U.S. federal government, after the president of the United States, and ranks first in the presidential line of succession. The vice president is also an officer in the legisl... |
What happened to all the Aircraft Carriers from WW2? How come Russia only has one aircraft carrier despite the Cold War? | Some are lying at the bottom of the Pacific Ocean, most have been scrapped and precious few have been preserved as Museum ships. Four *Essex*-Class carriers, *Hornet, Intrepid, Yorktown, Lexington* have been preserved. It is an exceptionally expensive exercise to preserve a ship of that size.
When considering why Russ... | [
"The first naval aviation units in Russia were formed from 1912 through 1914 as a part of the Soviet Baltic Fleet and the Soviet Black Sea Fleet. Since its formation, it has participated in the Russian Civil War, World War II and in many other conflicts throughout Europe, the Middle East and Asia (\"statement requi... |
how does an snes game get converted into a rom and played on a pc? | It boils down into two pieces - the ROM image itself and an emulator.
The ROM image is a copy of the cartridge. A cartridge is basically the same thing as a USB flash drive, but you can only write information to it once which is why it's named Read Only Memory. With the right hardware it's possible to read it out a sa... | [
"ROMs can be copied from the read-only memory chips found in cartridge-based games and many arcade machines using a dedicated device in a process known as \"dumping\". For most common home video game systems, these devices are widely available, examples being the Doctor V64 or the Retrode.\n",
"The BASIC ROM can ... |
season 2 of true detective | Part 1: Dear god. The best way to plot diagram this season would be with a spiral graph. I'll take a shot at it from memory.
During the LA riots the Casper character and maybe the Vinci chief of police? knock over a jewelry store to get some stones to sell, so they can buy their way into nice government jobs with in ... | [
"The first season of \"True Detective\", an American anthology crime drama television series created by Nic Pizzolatto, premiered on January 12, 2014, on the premium cable network HBO. The principal cast consisted of Matthew McConaughey, Woody Harrelson, Michelle Monaghan, Michael Potts, and Tory Kittles. The seaso... |
Question about the Croatian Coat of Arms and the Yugoslavian conflict of the 1990s | I believe you got two issues mixed up, the old "first field white or red" debate on the Croatian coat of arms and the general unease about using Croatian symbols. But let's go from the top:
Nationalism was always the greatest issue in Yugoslavia and when the situation in the country started firing up in the early 90s,... | [
"The 1991 Yugoslav campaign in Croatia was a series of engagements between the Yugoslav People's Army (JNA), the Yugoslav Navy and the Yugoslav Air Force, and the Croatian National Guard (ZNG) then the Croatian Army (HV) during the Croatian War of Independence. The JNA was originally deployed in order to preserve Y... |
variable change using the ‘goat/car behind the door’ and picking door 1. door 3 is exposed as a goat, why should you now change your selection to door 2? | Remember, the guy opening the other door Knows wich door the goat is behind. Think of his action as introducing new information to the problem
Say there were ten thousand doors, you chose door 9567. He then opens nine thousand nine hundred and ninety eight other doors. Leaves one closed. Remember, he knows where the ... | [
"The solution presented by in \"Parade\" shows the three possible arrangements of one car and two goats behind three doors and the result of staying or switching after initially picking door 1 in each case:\n",
"A parking pawl is a device fitted to a motor vehicle's automatic transmission in order for it to lock ... |
during opening credits of a tv show, all of the actors and actresses names appear at the bottom of the screen but the last person getting the credit gets a special "derp mcderpison as steve" credit. why is that? | Contracts. If given the choice, all the actors would want more money for appearing in a show. The unions generally set the pay scale, so more money is out. The next thing the actor wants is more work. More work means more money. The easiest way to get more work is to have more people know your name. So an actor would l... | [
"No supporting cast members are credited during the show's opening (though from the second season on, shots of them appear). The ending sequences show snippets of the cast, as well as any major guest stars in that episode, with the respective actors' names at the bottom of the screen. Other on-location scenes are a... |
how come you can throw a bug off the empire state building and it won't die, but after driving 80 mph on the highway my windshield is like a bug cemetery? | Because of terminal velocity. A bug thrown off a building will never reach anything resembling that speed, because of the wind resistance and their low weight. | [
"The dead break into their room and in desperation George throws a lit oil lamp at them. It smashes and the zombies burst into flame. The two escape to their car and Edna is sent off to tell the police. George plans to use the unmarked police car to go and smash the machine but it has no key so he runs off. At the ... |
why do some people feel more comfortable in the city, while others are more at home in the country? | preference.... I am not aware of any specific cause.
The human brain rebels against monotony and sameness so that might have something to do with it. | [
"In some countries rural inhabitants have been given even more reasons to migrate to the city by lower food prices in the cities, often because of pressure from trade unions. This in turn has led to lowered income in rural areas and therefore higher migration to urban areas. (Rakodi, 1997; Aase, 2003).\n",
"Many ... |
New Ketamine based anti-depressant Spravato, how does it work? | There are a number of speculative, educated guesses about how/why ketamine and its analogues might work to rapidly alleviate depression, but no one is sure. This isn't unusual. In fact, the precise pain-reducing mechanism of Tylenol (acetaminophen) is even't known, although (like with ketamine) there are a few hypothes... | [
"Ketamine has been found to be a rapid-acting antidepressant in depression. It also may be effective in decreasing suicidal ideation, although based on lower quality evidence. The antidepressant effects of ketamine were first shown in small studies in 2000 and 2006. They have since been demonstrated and characteriz... |
did telephone companies pay to have operators work overnight or did your phone have 'hours' similar to the way television did? | Is this story set in a big city?
Does being an operator play into the story?
So, yes, there were operators working at night in the fifties, especially for international and long distance calling and also running the local exchange in smaller towns. Local exchanges in the larger cities were doing direct dial by the e... | [
"While the promptness of service pleased businessmen who were in the office by 7:00 am, the early hour irked people who were at home so much so that telephone service to private residences didn't take off until 1904, when other systems of equipment testing were devised.\n",
"Night service in telephony is a featur... |
If I drop a live wire in the tub with me, I'm going to get shocked. If I'm in the ocean and someone drops a live wire in miles away, will I get shocked? | I am on mobile so it's a pain in the ass to include reference links. I can add some later on if requested.
The resistivity of sea water is about 3 orders of magnitude lower than the bulk resistivity of a human body. The effective resistance between the ocean and ground would basically be zero compared to human + oce... | [
"Jumping wires have fallen out of use since the end of World War II, as the wire tends to vibrate at high underwater speeds creating noise that may be detected by an enemy using passive sonar, as well as causing hydrodynamic drag.\n",
"In January 2010, Hydro-Marine Construction divers assisted Atlantic City Elect... |
how come pathogen (bacteria, virii) that live on surfaces are able to transfer themselves when we touch those surfaces? how come its cell membranes aren't crushed by the pressure of our hand? | At that level, surfaces aren't smooth, there's plenty of books and crannies. Your tissues are also form soft and flexible at that scale.
But you likely are killing a bunch, there's just a bunch of crap absolutely everywhere. | [
"BULLET::::- Adhesion. Many bacteria must first bind to host cell surfaces. Many bacterial and host molecules that are involved in the adhesion of bacteria to host cells have been identified. Often, the host cell receptors for bacteria are essential proteins for other functions. Due to presence of mucous lining and... |
how do civilizations "decline" or "go away"? | They decline. They get worse.
Rome - Rome expanded and put the majority of it's military trust in newly conquered "barbarians" instead of Roman raised armies. This lead to numerous regions having a military loyal to only the local leader who paid them and who were trained enough to secede from the rest of Rome when so... | [
"Reversion/Simplification: A society's adaptive capacity may be reduced by either a rapid change in population or societal complexity, destabilizing its institutions and causing massive shifts in population and other social dynamics. In cases of collapse, civilizations tend to revert to less complex, less centraliz... |
What parts of the US Constitution were the least controversial? | [James Madison took a lot of notes during the debates.](_URL_0_) I don't have a direct answer to your question, but if you don't get any help from this subreddit, I would suggest looking at his notes. It is the most extensive record of what the delegates actually proposed, debated, and compromised on. The SCOTUS cit... | [
"The United States Constitution has been a notable model for governance around the world. Its international influence is found in similarities of phrasing and borrowed passages in other constitutions, as well as in the principles of the rule of law, separation of powers and recognition of individual rights. The Ame... |
Assuming DMT (or one of its analogues) is in fact endogenously produced in the brain, what could be its evolutionary function? | this is way out there....
while it doesn't seem to be immediately evolutionarily advantageous, it COULD provide a humane transition to post-body cognition after bodily death. Look up some of what Dr. Stuart Hameroff has to say about post-body cognition before unduly dismissing the idea. He provides an interesting argu... | [
"Neuromodulation is a relatively new field that combines the use of neurodevices and neurochemistry. The basis of this field is that the brain can be regulated using a number of different factors (metabolic, electrical stimulation, physiological) and that all these can be modulated by devices implanted in the neura... |
Why does rocket exhaust sometimes look like this. | Those are Shock Diamonds, which are a complex phenomenon resulting from supersonic flow in air:
_URL_0_
You don't always see them because they need specific conditions to form, or at least to be visible, including excess fuel in the exhaust stream. | [
"The rocket engine was a LOX-Ethanol, film-cooled, pressure-fed, blow-down design with a 10 to -long exhaust plume. Plume-seeding technology allowed the plume color to vary from red to green to yellow to better facilitate race spectators in keeping track of specific racers while in the air.\n",
"A rocket engine's... |
Why does the lake near me seem to dissipate storms? |
This has been removed because questions based on personal anecdotes tends to invite unconstructive speculations.
For more information regarding this and similar issues, please see the [FAQ.](_URL_0_.)
| [
"Sudden storms can whip up dangerous, steep waves on the surface of the lake. Their average height is , and their average length is . A prevailing north-easterly or south-westerly wind can push the water from the eastern basin of the lake (to the east of the Tihany Peninsula) into the western basin or on the contra... |
the difference between free will and random will. | How would the brain "possess a will free from cause and effect" exactly? | [
"Regardless of the validity of, or benefit of, belief in free will, it may be beneficial to understand where the idea comes from. One contribution is randomness. While it is established that randomness is not the only factor in the perception of the free will, it has been shown that randomness can be mistaken as fr... |
If chlorine is supposed to kill microbes in tap water, why is it safe to drink? | Chlorination in drinking water is low enough not to cause any significant harm to humans due to our size and ability to deal with small amounts of toxic material. Given that microbes are microscopically smaller than us, the amount required to kill microbes in water is resultantly lower.
It can be likened to air in the... | [
"In much of the developed world, chlorine often is added as a disinfectant to tap water. If the water contains organic matter, this may produce other byproducts in the water such as trihalomethanes and haloacetic acids, which has shown to increase the risk of cancer. The level of residual chlorine found at around 0... |
how do people breathe when skydive? | You don't normally skydive from high enough for the thin air to have an effect (remember, you're falling really, really fast). Normal skydiving altitude is 10,000-12,000 feet (3,000-3,500 meters).
If you *do* skydive from a great height, you bring an oxygen tank with you. | [
"Breathing In, Breathing Out is a performance piece by Marina Abramović and Ulay. It was performed twice, in Belgrade (1977) and Amsterdam (1978). For this performance the two artists blocked their nostrils with cigarette filters and pressed their mouths together, so that one couldn’t inhale anything else but the e... |
how can a 128gb micro sd card be do much smaller than a 128gb solid state drive? why aren't solid state drives using this technology? | Although the internal circuitry of a SSD indeed has more complexity (it has cache, which is an intermediate faster memory "layer", and a more complex CPU), which indeed takes more space than what composes a simpler SD card, a huge part of that deck of cards size is empty.
It is made with that size for mechanical compa... | [
"Solid-state storage devices serve as secondary storage components for more complex systems, which may range from embedded and portable devices to large servers and dedicated network-attached storage (NAS) systems. As a result, solid-state storage devices exist in different capacities, physical layouts and dimensio... |
how do file converters work? | The details vary, but the idea is pretty simple. You load it in one format and save it in another.
For any file format, there is a way to load it up and convert it to a useful form (raw video, raw audio, raw images, text with formatting). The decoder.
There is also a way to convert from this useful form to a file for... | [
"Disk formatting is the process of preparing a data storage device such as a hard disk drive, solid-state drive, floppy disk or USB flash drive for initial use. In some cases, the formatting operation may also create one or more new file systems. The first part of the formatting process that performs basic medium p... |
Was Latin commonly spoken in western half of North Africa under Roman rule? | It is famously known that Saint Augustine, Church Father from the late IV^th and early V^th century, was a fluent Latin speaker of Northern African descent, with scholarly consensus on Berber origins. He was famously the bishop of Hippo (modern day Annaba Algeria) but born in Thagaste (same general area). He mentions w... | [
"The Roman African populations kept their Latin language, as well as their Catholic Christian religion, under the Germanic Vandal occupation, the Byzantine restoration and the Islamic conquest, where they progressively converted to Islam until the extinction of Christianity in the Maghreb in the 12th century under ... |
How is there more matter outside the observable universe? | As it would turn out, the observable universe is actually 92 billion light years across, 46 billion out in all directions. This is because space itself is expanding faster than light. Things can not move through space faster than light, but space itself can expand fast enough that a 13.5 billion old universe is much wi... | [
"As a matter of fact, the great majority of ordinary matter in the universe is unseen, since visible stars and gas inside galaxies and clusters account for less than 10 per cent of the ordinary matter contribution to the mass–energy density of the universe.\n",
"The remaining 4.9% of the mass–energy of the Univer... |
why do minor cuts and grazes only look a bit red but then the next morning they're big painful scabs | The blood is rushing to the wound (which makes it red). Your blood contains antibodies and things that eat up bacteria, viruses, and such. If the body detects a potential invasion, it pushes towards the spot in question. It's more of an evolutionary response though, your blood is under pressure and will push through an... | [
"Frequently, the bite is not initially felt and may not be immediately painful, but it can be serious. The brown recluse bears a potentially deadly hemotoxic venom. Most bites are minor with no necrosis. However, a small number of brown recluse bites do produce severe dermonecrotic lesions (i.e. necrosis); an even ... |
what would the consequences be if a united states president was found to have colluded with a foreign power for election? | Nothing. His party controls Congress and his voters don't care about that. Most likely, it will just be used to distract us from his dismantling of our safety nets and large give always to the rich. | [
"This however, also means that the president does not have to accept a proposal from the government either. He could even replace the Chancellor, to receive proposals such at will, and dissolve the National Council before it can initiate a vote of no confidence against the new Chancellor. So far – although this wou... |
In ancient phalanx warfare, how was determined who would fight where in the phalanx? | Being in the front row was a big deal. Statues commemorating the dead would mention that the man fought in the front row in battle, for example the [Kroisos Kouros](_URL_0_)
> στε̑θι ∶ καὶ οἴκτιρον ∶ Κροίσο παρὰ σε̑μα θανόντος ∶ / ℎόν ποτ’ ἐνὶ προμάχοις ∶ ὄλεσε θο̑ρος ∶ Ἄρες.
>
> "Stop and show pity beside the mar... | [
"The \"phalanx\" was an army tactic the Greeks performed with shields. Each soldier carried a shield in his left arm, which he used to protect both himself and the man on his left. The depth of the phalanx differed depending on the battle and commander, but the width of the formation was considerably greater than i... |
Microwave safe glass container, but the plastic lid isn't microwave safe but I still put it in the microwave is that bad? | I think if it is labeled as not safe it's possible if left to long it could melt and if plastic melts it wouldn't be good if it was on your food. If it doesn't melt or warp Im sure you are fine. Also melting plastic might catch fire if the conditions are right. I think you'd have to leave it on high for a seriously lon... | [
"Some current plastic containers and food wraps are specifically designed to resist radiation from microwaves. Products may use the term \"microwave safe\", may carry a microwave symbol (three lines of waves, one above the other) or simply provide instructions for proper microwave use. Any of these is an indication... |
why is dredging the great barrier reef an attractive option to mining companies? | If what I've read in the past is correct, this is being done so large barges/boats can use this area as port for shipping mined product because it's closer to the mines or has better access to seaways. | [
"Contrary to early hopes that seabed mining would generate extensive revenues for both the exploiting countries and the Authority, no technology has yet been developed for gathering deep-sea minerals at costs that can compete with land-based mines. Until recently, the consensus has been that economic mining of the ... |
Did the ancient Greeks ever realize that pedophilia was wrong? Did they ever have opponents in the society itself? | The answer really depends on how we consider the question. For instance, if we were to ask whether ancient Greeks in the Classical period considered it automatically wrong to have sexual contact with an individual under the age of say, 18, the answer would be “no”. If we were to ask whether Classical Athenians or Spart... | [
"Pedophilia is one of the most stigmatized mental disorders. One study reported high levels of anger, fear and social rejection towards pedophiles who have not committed a crime. The authors suggested such attitudes could negatively impact child sexual abuse prevention by reducing pedophiles' mental stability and d... |
Did the Confederacy ever have a plan to annex Maryland or its Eastern Shore? | They wanted Maryland, expected Maryland to join them, and deluded themselves into thinking that Marylanders preferred the Confederacy but were being held in the Union by the state and federal governments. There was a substantial secessionist minority, but no overwhelming public demand for secession. When Lee invaded Ma... | [
"Because the fortieth parallel lay north of the city of Philadelphia, Maryland pressed its claim most seriously in the sparsely inhabited lands west of the Susquehanna River. By the late 1710s, rumors had begun to reach the Pennsylvania Assembly that Maryland was planning to establish settlements in the disputed ar... |
Was the American prison system ever focused on rehabilitation? If so, what caused the change to focusing on punishment? | This is a complex question and not really in the realm of US legal history that I have spent the most time in, so I will try to outline the specific limitations of what I am saying as I go along. The short answer is that as part of the systematization of mass incarceration in the 19th century, the United States did ini... | [
"A new group of prison reformers emerged in the Reconstruction Era that maintained some optimism about the institution and initiated efforts to make the prison a center for moral rehabilitation. Their efforts led to some change in contemporary prisons, but it would take another period of reform during the Progressi... |
What happens to photons that are emitted into empty space with nothing in its path to absorb it? | > Does it just travel on for eternity?
Yes, until it hits something.
> What if a photon isn't emitted unless it will be absorbed?
Emission of a photon has to happen before its absorption. What you're saying isn't possible, as it would violate causality. A "later" event cannot be the cause of an "earlier" event.
... | [
"In a process in which a photon is annihilated (absorbed), we can think of the photon as making a transition into the vacuum state. Similarly, when a photon is created (emitted), it is occasionally useful to imagine that the photon has made a transition out of the vacuum state. An atom, for instance, can be conside... |
Question regarding Norse and Slaves | I'd call it plausible but not probable.
Firstly, the situation in China is a bit of an issue, as the probability of a westward traveller in the period described is somewhat slim. The 'Viking Age' (if defined as beginning with the Lindisfarne raid in 793) would have encompassed three periods in Chinese dynastic history... | [
"In the Viking era beginning circa 793, the Norse raiders often captured and enslaved militarily weaker peoples they encountered. The Nordic countries called their slaves \"thralls\" (Old Norse: \"Þræll\"). The thralls were mostly from Western Europe, among them many Franks, Frisians, Anglo-Saxons, and both Irish a... |
why do i have sudden spurts where i have to get up and pee every 15 minutes and the urine is perfectly clear even though i haven't drank any water? | I don't have any idea. You should probably consult a doctor or pharmacist about any medical related questions/issues you may have or at least go to _URL_0_ | [
"BULLET::::- Overflow incontinence: Sometimes people find that they cannot stop their bladders from constantly dribbling or continuing to dribble for some time after they have passed urine. It is as if their bladders were constantly overflowing, hence the general name overflow incontinence.\n",
"Overflow incontin... |
in linux, what does 'bash' and 'shell' mean? | Bash means Bourne Again Shell and a shell is the interactive program that allows you to type commands and executes them. It allows you to interact with the OS using a text-only interface. Bash is just a specific shell, there are other shell programs such as Zsh. | [
"Bash is a Unix shell and command language written by Brian Fox for the GNU Project as a free software replacement for the Bourne shell. First released in 1989, it has been used widely as the default login shell for most Linux distributions and Apple's macOS Mojave and earlier versions. A version is also available ... |
How do you calculate the yield of a TNT blast? | I think what you mean is not the yield (which is just an energy release — 1 ton of TNT has the yield of 1 ton of TNT, boring!), but the blast radius (what blast pressure would happen at what amount of TNT).
The easiest way to do this is with the Sadovsky formulas. They allow you to trace the pressure of a blast wave ... | [
"BULLET::::- One megatonne of TNT equivalent amounts to approx. 4 petajoules and is the approximate energy released on igniting one million tonnes of TNT. The unit is often used in measuring the explosive power of nuclear weapons.\n",
"The explosive yield of a nuclear weapon is the amount of energy released when ... |
Does weighing more keep you warmer in the winter? If so, to what extent? | This can actually be explained fairly simply. Heat loss is dependent on surface area. The square-cube law is used to refer to the fact that as the size of an object increases, the surface area is squared and the volume is cubed. Essentially, as an object gets larger, surface area increases slower than volume. So the mo... | [
"The Utah model assigns different weight to different temperature bands; a full unit per hour is assigned only to temperatures between and . Maximum effect is achieved at . Temperatures between and (the threshold between chilling and warm weather) have zero weight, and higher temperature have negative weights: they... |
why don't terrorists use wildfires as a weapon? | Thanks for giving 'em ideas, dude.
Seriously, though, the purpose of terrorism is to *scare people.* That's why it's called "terrorism." Wildfires aren't scary. Planes crashing into buildings or busses exploding are scary. | [
"Wildfire risk is the chance that a wildfire will start in or reach a particular area and the potential loss of human values if it does. Risk is dependent on variable factors such as human activities, weather patterns, availability of wildfire fuels, and the availability or lack of resources to suppress a fire. Wil... |
How does electrical input become digital information? | It's a very complex topic, as there are a lot of steps involved in the process. However, some basic ideas are easier to grasp. If you have time, I recommend reading [Code by Charles Petzold](_URL_1_), it explains these things in a clear way and much better than my comment.
Edit: for a better explanation that is long... | [
"A digital input indicates if a device is turned on or not - however it was detected. Some examples of an inherently digital input would be a 24 V DC/AC signal, current switch, an air flow switch, or a volta-free relay contact (dry contact). Digital inputs could also be pulse type inputs counting the frequency of p... |
How were Japanese men and women, who married Koreans, viewed during the Japanese occupation of Korea? | So to understand this, we'll have to understand how the "normal" Japanese were viewed in Korea.
The Japanese government, like the US government during the 19th century, British crown, and several other colonial powers did with their lands, promoted Korea as extremely arable land, offered acres to people who would sett... | [
"The earliest known Koreans in Palau are believed to be 10 comfort women who arrived in 1936. As the demand for labour increased sharply with the onset of war, Japanese authorities turned to the Korean peninsula as a source of cheap workers. The first Korean labourers came in January 1939, a group of 500; they were... |
What is the advantage of using rubbing ethanol vs rubbing isopropanol? What is the point of selling rubbing ethanol? | If they don't make it inedible it's taxed as liquor. Isopropyl alcohol is toxic to consume (in significant quantities) so it's way easier to sell untaxed and to minors. Ethanol requires all sorts of things added to it to make it inedible. With that said, ethanol is easier to produce (any old yeast will do) and it's eas... | [
"Rubbing alcohol refers to either isopropyl alcohol (propan-2-ol) or ethanol based liquids, or the comparable British Pharmacopoeia defined surgical spirit, with isopropyl alcohol products being the most widely available. Rubbing alcohol is undrinkable even if it is ethanol based, due to the bitterants added.\n",
... |
LEDs and Colder Temperatures? | Two ways. For most uses, the cooling prevents over-temperature failure. The bond wire is very thin and melts if too hot.
Second, for cryogenically cooled LEDs, the valence electrons in cooled atoms are more likely to be in lower bands making the average band gap larger. That makes the color shift towards shorter wave... | [
"Compared to other lighting systems LEDs must be kept cool as high temperatures can cause premature failure and reduced light output. Thermal management of high-power LEDs is required to keep the junction temperature close to ambient temperature. LED lamps typically include heat dissipation elements such as heat si... |
Can we have twin planets like we have twin stars? | Yes. The Earth-Moon system is very close to a twin planet.
Luna in comparison to Earth is the second largest mass ratio in the solar system, I believe second only to Pluto/Charon. It is so large, in fact, that not only does the moon orbit the Earth, Earth orbits the moon. Their common barycenter is not the center of ... | [
"Some other stars are sometimes mentioned as solar-twin candidates such as: Beta Canum Venaticorum; however it has too low metallicities (–0.21) for solar twin. 16 Cygni B is sometimes noted as twin, but is part of a triple star system and is very old for a solar twin at over 9 Gyr.\n",
"Another way of defining s... |
imaginary powers | You just have to expand your definitions.
The basic definition of p to the exponent n as repeated multiplication of p nth times is fine and dandy but it's only possible for integer n.
To extend it to n and p real or complex, you have to use the exponential and logarithms function. For each real number it's easy to de... | [
"The \"other imaginary quantities\" needed for the \"theory of residues of higher powers\" are the rings of integers of the cyclotomic number fields; the Gaussian and Eisenstein integers are the simplest examples of these.\n",
"Wolin explains that the constitutional imaginary \"prescribes the means by which power... |
this common core 2nd grade math problem | The teacher, most likely, wanted the workout, such as:
Q: Explain why 24+30=54
A: 24-4=20
20+30=50
50+4=54
I don't know exactly how the common core teaches addition/multiplication, but I believe they like to do that whole getting multiples of 10 and adding the difference ... | [
"Blue Ridge Elementary School achieved a score of 84.5 out of 100. The score reflects on grade level: reading, science, writing and mathematics achievement. In 2012-13, only 73% of the students were reading on grade level in grades 3rd through 5th. In 3rd grade, 73% of the pupils were reading on grade level. In mat... |
How does communication encryption prevent eavesdropping? | It's a trick called public-key encryption. Essentially, each party has 2 keys, a public key that can be used to encrypt data (but not to decrypt it), and a private key that can be used to decrypt data. They give the other party the public key, which allows each party to communicate to the other data that only the other... | [
"Encryption is another form for privacy security. When organizations do not have secure channel for sending information, they use encryption to stop unauthorized eavesdroppers. Encryption is the process of converting an original message into a form that cannot be read by anyone except the intended receiver.\n",
"... |
what do terrorists want? | What terrorists want depends largely on the group, there are a lot of different motiviations.
ISIS, the latest big name in fanaticism, is at it's core a doomsday cult. They believe they know the time & the place of the apocalypse and the ultimate showdown between good and evil: The place is an otherwise-unexciting t... | [
"Terrorists have tended to be from among the more well educated in their host countries. They often have developed a well thought out, but not very often publicized or well articulated, rigid ideology that provides the foundation for their strategy and tactics. Psychologically disturbed terrorists increase the risk... |
why do some scientists warn about ai becoming self aware? | Because we don't know what it will be capable of or what it's intentions will be. If an AI becomes capable of improving itself it could become out of control and escalate it's abilities, and without morals it could go on as rampage destroying financial systems, traffic systems, power grid infrastructure, all kinds of t... | [
"A company called Artificial Life Solutions experiments with various artificial intelligence solutions, but something unexplained causes some AIs to become self-aware. These AIs perceive their digital world as a 2D space with themselves represented as quadrilateral shapes.\n",
"BULLET::::- \"The AI effect\": Mach... |
Explain the subjective jumping of CRT displays and some digital clock (7segment LED) displays seen when chewing/jaw grinding. | It's because we don't see in frames per second, but we see a constant light.
25FPS for smooth motion is just an illusion, we can see hundreds of frames per seconds according to the right conditions.
now, when you blink, swing an alarm clock, etc you see the blinking that you otherwise don't notice. | [
"\"Rapid serial visual presentation\" is a Paradigm used by psychologists to study an attentional phenomena named \"the attentional blink\". The RSVP tasks asks a participant to observe a continuous presentation of multiple separate visual images or objects that appear in rapid succession (very short duration of ex... |
friction and energy can cause heat, but what exactly causes something to cool down? | If one thing is hotter than its environment it cools down by distributing its energy to the environment, however what you wante to know is how heat is converted to different forms of energy if i understood correctly. The simplest example is a chemichal reaction that forms a bond between two or more atoms or molecules u... | [
"When surfaces in contact move relative to each other, the friction between the two surfaces converts kinetic energy into thermal energy (that is, it converts work to heat). This property can have dramatic consequences, as illustrated by the use of friction created by rubbing pieces of wood together to start a fire... |
Why do Ultra Orthodox or Hassidic Jews dress in old timey clothing? | While this question is totally appropriate for /r/askhistorians, I think you're much more likely to get an answer in /r/judaism. | [
"Many Orthodox Jews can be identified by their manner of dress and family lifestyle. Orthodox men and women dress modestly by keeping most of their skin covered. Married women cover their hair, with either scarves (tichel), snoods, hats, or wigs. Orthodox men are expected to wear a ritual fringe called Tzitzit, and... |
how converging diverging nozzles work in relationship with supersonic travel. | Imagine you're blowing air through a straw that has a little pinch in the middle. You start softly, but slowly increase the pressure you're blowing with. What you notice is the air is coming out at the other end speeds up the harder you blow.
If it was possible for you to blow so hard you could get the air to move at ... | [
"If, however, a convergent-divergent de Laval nozzle is fitted, the divergent (increasing flow area) section allows the gases to reach supersonic velocity within the divergent section. Additional thrust is generated by the higher resulting exhaust velocity.\n",
"The obvious result is that in order to accelerate a... |
Found a very strange tiny skull in my garden, what IS it? | That actually looks like a vertebrae, not a skull. | [
"Talenkauen (meaning \"small skull\" in Aonikenk, referring to the proportionally small skull) is a genus of basal iguanodont dinosaur from the Cenomanian-age Late Cretaceous Cerro Fortaleza Formation, formerly known as the Pari Aike Formation of Patagonian Lake Viedma in the Austral Basin of Santa Cruz, Argentina.... |
Would it be possible to make teeth completely from human enamel? | Bone and enamel are both a type of calcium phosphate called hydroxyapatite with a collagen substructure. The difference between the two is mainly in porosity and mineralization - enamel is 98% mineral, bone is 70-90, depending on location, and bone is generally more porous than enamel. We can synthesize hydroxyapatite ... | [
"Enamel is the hardest substance in the human body and contains the highest percentage of minerals (at 96%), with water and organic material composing the rest. The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate. Enamel is formed on the tooth while the tooth develops within the jaw bone... |
Did the Zika virus mutate in South America or are people of SE Asia descent naturally not affected by microcephaly due to this virus? or are there other confounding factors? | Zika is a big problen mostly because it is new in Brazil. Even in SE Asia, there is few information on medical literature about zika (ex. it is not clear yet if zika is sexually transmited, there is only 2 cases of sexual transmition evidence on entire medical literature)
Brazilian doctors believe that zika came to So... | [
"After the detection of zika virus in Brazil in April 2015, the first ever in the Western Hemisphere, it is now thought some chikungunya and dengue cases could in fact be zika virus cases or coinfections.\n",
"Following the spread of Zika infection into Southeast Asia in June 2016, Singapore, Thailand and Vietnam... |
what causes to us to wake up and forgot where we are for a few brief seconds? | The brain isn't something that just turns on full power and shuts down to 0 power when not in use. It needs to warm up, and take in its new (remember you just spent hours somewhere else in your dreams) surroundings to build context and put meaning behind what it sees. When you wake up, its not like your brain is at 100... | [
"When awake, our brainwaves are faster during the first half of the cycle, when we feel alert and focused, and then our brainwaves slow; in the last 20 minutes when we feel dreamy and perhaps a little tired, while our body is being readied for the alert part of the following cycle. \n",
"The perception of time is... |
What makes the difference between a figure being mythical/legendary and historical? | The difference between legendary and historical figures is somewhat vague, but the ideal evidence for the historical existence of a person or ruler would be the existence of contemporaneous textual source material directly related to that person. In practice, historians dial with a variety of texts and materials with v... | [
"The \"Legends\" are a variety of romantic tales. As the name implies, most have a legendary tone. Some depict supernatural and semi-religious (Christian) events, like \"The Mount of the Souls\", \"The Green Eyes\", \"The Rose of the Passion\" (a blood libel) with references to the Holy Child of la Guardia and \"Th... |
why is the movie frozen seen as a metaphor for homosexuality? | Elsa has a condition that is shameful, and that her parents want her to hide and never let anyone else see. If they could cure it, they would, but they can't. Elsa suppresses her feelings and lives a sad, unfulfilled life hoping that no one figures out the truth about her. When people do find out, they react poorly, an... | [
"Several viewers outside the film industry, such as evangelical pastors and commentators, argued that \"Frozen\" promotes normalization of homosexuality, while others believed that the main character, Elsa, represents a positive image of LGBT youth, viewing the film and the song \"Let It Go\" as a metaphor for comi... |
why is it easier to peddle uphill standing up? | You can use your weight optimally to press down on the pedal from the standing position. When sitting most of your weight is on the seat so your leg muscles do almost all of the work without your body weight to assist. | [
"\"You should bend your knees from the thighs down. As your knees bend, the upper part of the trunk remains normally erect, just as it does when you sit down in a chair. In golf, the sit-down motion is more like lowering yourself onto a spectator-sports-stick. Think of the seat of the stick as being about two inche... |
How does gravity have a repulsive force? | Newtonian gravity, F = GmM/r^2 as taught in high school, is always attractive.
Newtonian gravity is approximately correct, but breaks down for extremely large scale systems such as the observable universe, and very dense systems such as neutron stars. If you observe the orbit of Mercury with incredible precision, over... | [
"Gravitation acting alone does not produce a g-force, even though g-forces are expressed in multiples of the free-fall acceleration of standard gravity. Thus, the standard gravitational force at the Earth's surface produces g-force only indirectly, as a result of resistance to it by mechanical forces. It is these m... |
What happened to all the anti-matter? | Yes, where did all the antimatter go? It's a good question and the answer is both disappointing and interesting: We don't know. In (astro)physics, this question is referred to as the "Baryon Asymmetry Problem" because of the apparent asymmetry between baryonic matter (everyday matter composed of quarks) and antibaryoni... | [
"When matter and antimatter come into contact, they annihilate—both matter and antimatter are converted directly and entirely into enormous quantities of energy, in the form of subnuclear particles and electromagnetic radiation (specifically, mesons and gamma rays). In the \"Star Trek\" universe, fictional \"dilith... |
how are people influenced to vote against their own self-interests? | Either
1) they are uncertain about what is in their best interest (the economy is complex. If you are minimum wage worker will a minimum wage increase boost your earnings or cut your job).
2) they believe their circumstances will change such that their self interests will come into line with their current vote (the ... | [
"The egocentric bias has also been shown to contribute to a citizen's decision to vote in elections. Firstly, people tend to view their personal choice between voting and abstinence as a reflection of those who support the same candidates and issues. Secondly, although each individual vote has very little power in ... |
Does a baseball really travel farther in humid weather? | Yup. [Drag](_URL_0_), or air resistance in this case, is proportional to the density of the medium the projectile is traveling through. Water molecules weigh only 18 amu, compared to other main atmospheric gases oxygen (32 amu) and nitrogen (28 amu). For a given temperature, there are always about the same number of ga... | [
"Another use for a humidor is controlling the moisture level in a baseball, which can have a pronounced effect on its response when hit with a baseball bat. This phenomenon was so great that in order to put an end to much controversy, in 2002, nine years after joining the league, the Colorado Rockies started storin... |
why do men play baseball, but women play softball? what is the difference? | Softball was invented in a windy day in 1887 in Chicago, Ill., by a group of men waiting for results of the Harvard-Yale football game. While they were waiting, they turned a glove tied together into a large ball, with a broomstick as the bat. It was first regarded as a way to play baseball indoors, and after it gained... | [
"College softball is softball as played on the intercollegiate level at institutions of higher education, predominantly in the United States. College softball is normally played by women at the Intercollegiate level, whereas college baseball is normally played by men.\n",
"The principal difference between tee-bal... |
What's the highest frequency laser? | It depends what you mean by a laser. If it actually has to work through a lasing mechanism (involving population inversion and whatnot), the current limits are in the ultraviolet. I read a paper a few years ago claiming to get 10 nm radiation...I don't know if that's a record or what.
Above that there are free-electro... | [
"Since no real laser is truly monochromatic, all lasers can emit light over some range of frequencies, known as the linewidth of the laser transition. In most lasers, this linewidth is quite narrow (for example, the nm wavelength transition of a has a linewidth of approximately 120 GHz, or 0.45 nm). Tuning of the ... |
Have we determined if any anisotropies in the Cosmic Microwave Background correspond to closer, less redshifted, visible large scale structures or voids ? | There are claims that the [cold spot](_URL_4_) in the CMB is due to a large underdensity, or "supervoid" (some examples here: [\[1\]](_URL_5_), [\[2\]](_URL_3_), [\[3\]](_URL_2_)). However, the void would have to be exceptionally large to explain the cold spot - in fact one of the largest structures detected in the obs... | [
"In 2010, Penrose and Vahe Gurzadyan published a preprint of a paper claiming that observations of the cosmic microwave background (CMB) made by the Wilkinson Microwave Anisotropy Probe (WMAP) and the BOOMERanG experiment contained an excess of concentric circles compared to simulations based on the standard Lambda... |
is there an infinite amount of time in between each second? | Just because there are an infinite number of numbers between 1 and 2, doesn't mean that those numbers are infinitely large.
To put that another way, there are an infinite number of values between 1 and 2, but none of them are 3, 4, 100, or twenty billion.
So the amount of time between 1 and 2 seconds is exactly one s... | [
"In this table, large intervals of time surpassing one second are catalogued in order of the SI multiples of the second as well as their equivalent in common time units of minutes, hours, days, and Julian years.\n",
"In principle, time spans greater than one second are given in units such as kiloseconds (ks), myr... |
pgp | The cool part about public key cryptography is that you can use the public key to verify that somebody else has the matching private key without knowing what the private key is.
When you sign a message with PGP, you use the private key to put a code in the message. You combine that code with the public key to verify t... | [
"PPP is commonly used as a data link layer protocol for connection over synchronous and asynchronous circuits, where it has largely superseded the older Serial Line Internet Protocol (SLIP) and telephone company mandated standards (such as Link Access Protocol, Balanced (LAPB) in the X.25 protocol suite). The only ... |
what elements make pirate music sound like pirate music? | You're thinking of a shanty, which is those songs they sang as a group to aid productivity.
So key elements would be piratical subject matter and repetitive, easy to remember lyrics in an energetic fashion.
I only know this due to video games. Assassin's Creed 4 was set in the West Indies during that time and there's a... | [
"Elsewhere, the music on \"Pirates\" is often cinematic, with influences ranging from Leonard Bernstein to Bruce Springsteen and Laura Nyro. The album is more musically ambitious than its predecessor, and explores elements of jazz, R&B, bebop, pop and Broadway, with multiple changes in tempo and mood within most so... |
Was there any James Bondesque type spying done during WWII and the cold war? What I mean is more open fighting, direct assassinations, and much more open use of weaponry. | The Double Cross book is a very good example of this very thing. (Double-Cross)[_URL_1_]
this podcast:
_URL_0_
is a good starting point for more information with many first person accounts along with some historians.
| [
"James Bond is the most famous of film spies, but there were also more serious, probing works like le Carré's \"The Spy Who Came in from the Cold\" which also emerged from the Cold War. As the Cold War ended, the newest villain became terrorism and more often involved the Middle East.\n",
"The policy of MI5 durin... |
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