question stringlengths 3 301 | answer stringlengths 9 26.1k | context list |
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What stopped Spain and Portugal from claiming the Magreb region of Africa and attracted France to it instead? | If I am correct, Spain launched numerous crusades into north Africa capturing cities like Oran (1509), Melilla (1497), and Tripoli (1511), however they were not able to hold them for long. Portugal also launched crusades into Morocco, capturing Ceuta (1415), Tangiers (1471), and Mazagan (1485). Although Portugal was ab... | [
"Portugal and Spain passed an agreement in 1496 in which they effectively established their zones of influence on the North African coast: Spain could only occupy territory east of Peñón de Vélez. This restriction would only end with the absorption of Portugal into the Spanish crown of Philip II after the 1578 Batt... |
How fast does cells and bacteria move inside your body? | Im gonna talk about immune cells like macrophagrs and neutrophils because human cell motiliy is a more difficult subject. The cells themselves that do move don't cover a lot of distance on their own. Even a 'fast' cell is tiny. This is one of the reasons we have blood! It conveys your absorbed nutrients and oxygen and ... | [
"The cells of the human body have many structures which move throughout them. Cytoplasmic streaming is a way which cells move molecular substances throughout the cytoplasm, various motor proteins work as molecular motors within a cell and move along the surface of various cellular substrates such as microtubules, a... |
why are cop shows so popular? | Everyone else is wrong.
Cop shows (and doctor shows, lawyer shows, detective shows, forensic shows, etc.) are popular because, properly produced, they don't descend into melodrama. Stories, particularly novels, tend to be about the most important thing that happens in a character's life. This works fine for a novel,... | [
"About the series, Breckman said, \"Many cop shows feature dark and provocative material: psycho-sexual killers, twisted, grim, flawed detectives. Many address the most controversial issues of the day. I watch a lot of them. God bless 'em all. But the show I want to produce is playful, family-friendly, and a celebr... |
Do cephalopods control their camouflage consciously, if yes how exactly can an animals thought's change it's cells? | They might have a totally different consciousness from us; some pretty serious theories are being knocked around that suggest that each arm is intelligent and conscious: _URL_0_
So it might not even make sense to ask whether a cephalopod consciously "decides" anything in the same sense that we do. (Skipping over the q... | [
"Cephalopods can change their colors and patterns in milliseconds, whether for signalling (both within the species and for warning) or active camouflage, as their chromatophores are expanded or contracted. Although color changes appear to rely primarily on vision input, there is evidence that skin cells, specifical... |
what are phobias and what does it feel like to have one? | A phobia is a fear of a specific thing or situation that causes so much anxiety it impacts your life in some way--for example, you have a hard time working or going out with friends, it's difficult to go about daily tasks, that sort of thing.
Here's an example. A lot of people are a little nervous about flying. But wh... | [
"A specific phobia is any kind of anxiety disorder that amounts to an unreasonable or irrational fear related to exposure to specific objects or situations. As a result, the affected person tends to avoid contact with the objects or situations and, in severe cases, any mention or depiction of them. The fear can, in... |
What is the smallest object or length that we could possibly actually see? | It's time to bust out the Abbe limit. Back in the 19th century, this was a hot question (for obvious reasons: people wanted to build better microscopes). Guys like Helmholtz, Abbe, and Zeiss were all working on this problem.
The resolution of an optical microscope is limited by two things: the numerical aperture (whic... | [
"Observing a nearby small object without a magnifying glass or a microscope, the size of the object depends on the viewing distance. Under normal lighting conditions (light source ~ 1000 lumens at height 600–700 mm, viewing angle ~ 35 degrees) the angular size recognized by naked eye will be round 1 arc minute = 1/... |
Why aren't photons affected by the Higgs field? | By definition!
Photons are by definition the single component of the original SU(2)×U(1) electroweak gauge field that leaves the Higgs vacuum expectation value invariant. This means that the VEV is uncharged for the photon, and the photon aquires no mass.
A little simpler: basically, SU(2)×U(1) is a four dimensional ... | [
"The Higgs condensate in this model has infinitesimal charge, so interactions with the Higgs boson do not violate charge conservation. The theory of quantum electrodynamics with a massive photon is still a renormalizable theory, one in which electric charge is still conserved, but magnetic monopoles are not allowed... |
How historically accurate is "Kingdoms of heaven" | In wine tasting (and other culinary arts) there is a concept of *mouthfeel*. The idea that independent of taste a wine should feel a certain way in the mouth. A port should feel thick and syrupy. A champagne should feel light and bubbly. Movies have a similar thing, where a lot of details have to be done correctly to c... | [
"In the time since the film's release, scholars have offered analysis and criticisms through a lens situating \"Kingdom of Heaven\" within the context of contemporary international events and religious conflict, including: broad post-9/11 politics, neocolonialism, Orientalism, the Western perspective of the film, a... |
Why is this light bulb lighting up? | Florescent lights work by creating free electrons shooting between high voltage anode and cathodes inside the near vacuum of the tube. The inside of the bulb is coated with substances that "fluoresce" --eg. that emit light when they are struck with free electrons. High voltage is required to get the electrons moving ar... | [
"The light itself is a third order Fresnel lens that was made in France. It used to be fueled by lard, later it was fueled by kerosene, then by acetylene, and now by electricity. The round ball at the top is the vent that removed the smoke and soot from the oil lamp. Each night oil had to be carried to the top of t... |
Can we predict where the Voyager probes will be in a hundred years (in relation to our Sun)? A thousand? A million? | I work on interplanetary and interstellar navigation solutions and your question is best answered with another question: how accurately do you need to know their position? Even now, we don't know their position to centimetre precision but we certainly know it to a kilometre or two. Interstellar forces play a big role a... | [
"The \"Voyager 1\" probe and Gliese 445 will pass one another within 1.6 light-years in about 40,000 years. By that time Gliese 445 will be in a part of the sky different from its present location. The probe will no longer be operational. Also, given the star's inherent low brightness, even at that distance it woul... |
crossbow vs compound bow | The draw weight is only half the equation for the energy of a projectile. The other is the draw distance.
The reason for that is simple: The longer you push against a moving object, the more it's going to speed up. That means that you can calculate the kinetic energy of a linearly accelerated object by multiplying the... | [
"A crossbow is essentially a bow mounted on an elongated frame (called a tiller or stock) with a built-in mechanism that holds the drawn bow string, as well as a trigger mechanism that allows the string to be released. \n",
"Although having the same launch principle, crossbows differ from bows in that a bow's dra... |
what makes some babies come early, and some come late? what tells the female body that it’s time to start labour? | This is just a theory I’ve seen in some research papers, but there seems to be suspicion that it’s up to the placenta.
The placenta is an organ that the mother’s body creates and it’s basically what’s in charge of nutrients for the fetus. The umbilical cord connects the baby to the placenta. If the placenta doesn’t ha... | [
"Common signs that labour, commonly spelled as labor, is about to begin may include \"lightening\". Lightening describes the baby moving down from the rib cage with the head of the baby engaging deep in the pelvis. The pregnant woman may then find breathing easier since her lungs have more room for expansion, but p... |
why do we never have any mist in the eyes during a sudden temperature change? | Are you asking why eyes don't fog up like glasses do when you go from cold to warm and humid?
That's because our eyes are already warmed by our body so they aren't really at condensing temperatures, also there are wet so any condensation that formed would just become part of the film of water that covers our eyes any... | [
"These make the eye's pupil widen to maximum, to let an optometrist have the best view inside the eyeball behind the iris. Afterwards in sunny weather they can cause dazzling and photophobia until the effect of the mydriatic has worn off.\n",
"Skeptical investigator Joe Nickell wrote that the \"dancing sun\" effe... |
Wikipedia says element 120 might be the last element possible to synthesize with current technology. Is this true? And if so, why can’t we synthesize further elements with our current technology? What new technology would we need to synthesize heavier elements like 121, 122? | I don’t see why there would be any hard cutoff at Z = 120. In principle, as long as you can find a beam and target combination such that their compound nucleus has a Z for at least 121, there’s nonzero probabaility that you’ll end up with some isotope of that element. Your experiment may have to run for a year, but tha... | [
"Ununennium and unbinilium (elements 119 and 120) are the lightest elements that have not yet been synthesized: all the preceding elements have been synthesized, culminating in oganesson (element 118), the heaviest-known element, which completes the seventh row of the periodic table. Attempts to synthesize elements... |
what was re-conversion like in Sicily following the Norman Conquest over the Fatimids? Was there an inquisition targeting crypto-Muslims like the one following the Iberian reconquista? | There was no systematic re-conversion, but there was (eventually) a mass expulsion of Muslims.
Hard numbers are always elusive in pre-modern history, but it seems that considerable numbers of Sicilians had converted to Islam, particularly in and around the major cities. In combination with migration from North Africa... | [
"In 827, the Moors occupied Mazara on Sicily, developing it as a port. They eventually went on to consolidate the rest of the island. Differences in religion and culture led to a centuries-long conflict with the Christian kingdoms of Europe, which tried to reclaim control of Muslim areas; this conflict was referred... |
What is physically different between the brains of people with "good memories" versus those with "bad memories"? | The [hippocampus](_URL_4_) is a part of the brain that plays a very important role formation of new memories. If a person has structural damage to the hippocampus, that causes issues with forming new memories. Alzheimer’s disease, for instance, is associated with [hippocampal damage](_URL_2_)--and memory loss is conseq... | [
"Positive autobiographical memories contain more sensory and contextual details than negative and neutral memories. People high in self-esteem recall more details for memories where the individual displayed positive personality traits than memories dealing with negative personality traits. People with high self-est... |
If all the gas was removed from the surface of Venus, Could we terraform it? | Venus without its atmosphere would still present major challenges. First off, the planet would still be very hot and it would take time to radiate that away.
Another challenge is Venus' extremely slow rotation. A "day" on Venus is 243 Earth days long.
Probably better to think of Venus' atmosphere in the sense of Eart... | [
"Terraforming the planet Venus by removing CO from the atmosphere was first scholarly proposed by the astronomer Carl Sagan in 1961, although fictional treatments, such as \"The Big Rain\" of The Psychotechnic League by novelist Poul Anderson, preceded it. Adjustments to the existing environment of Venus to support... |
Do we ever witness blatant behavioural or biological evolution in another species? | Within the lifetime of the specimen? no. a species evolves. an individual does not evolve, not genetically.
can a fast lifecycle species evolve in the lifetime of a human? yes!
a new variety of swallows has emerged due to highway traffic. the short wingtipped swallow is better at ~~catching bugs off the turbulent ai... | [
"BULLET::::2. Smale showed that Lotka-Volterra systems that meet the above conditions and have five or more species (\"N\" ≥ 5) can exhibit any asymptotic behavior, including a fixed point, a limit cycle, an \"n\"-torus, or attractors.\n",
"There is little known about the social and reproductive behavior of these... |
A question about condensation. | Here's my sorta eli5 explanation:
It's coming from the air. Essentially you can "dissolve" a certain amount of water in air. The hotter the air is, the more water it can hold. If it cools down, this water will form little droplets, so you get fog or rain.
Your bottle is colder than your room, so it cools the air arou... | [
"In physics, condensation refers strictly to gas-liquid phase transitions, while in biology the term 'condensation' is used much more broadly and can also refer to liquid-liquid, liquid-gel, or liquid-solid phase separation, as well as liquid-to-solid phase transitions such as DNA condensation during prophase of th... |
Why do hospitals have red crosses on them? | On Oct. 29, 1863, the delegates at the Geneva International Conference, also called the first conference of the International Committee for Relief to the Wounded, [signed the final resolutions of the conference](_URL_0_). Article 8 states:
> They shall wear in all countries, as a uniform distinctive sign, a white arm... | [
"Prior to 1973, ambulances in the United States and elsewhere in the Western Hemisphere were typically marked with a safety orange cross, differing from the red cross only in its hue. Toys and paintings of ambulances commonly ignored even that nuance, instead using a red cross. After protests from the American Red ... |
If Jupiter was condensed, how big would it be compared to Earth? | The problem is that the compositions of the planets are very different. The best way to do this would be to compare the masses.
Earth = 5.972E24 kg
Jupiter = 1.898E27 kg
If Jupiter's density was made to be the same density as Earth, it would be 1.898E27/5.972E24 = 317 times the size of the Earth in terms of volume. | [
"In 2011, Whitmire and Matese speculated that the hypothesized planet could be up to four times the mass of Jupiter and have a relatively high temperature of approximately , due to residual heat from its formation and Kelvin–Helmholtz heating. It would be insufficiently massive to undergo nuclear fusion reactions i... |
why is the sun so much hotter when it reflects off glass windows or buildings? | That should only be happening if you are in the focal point for the sunlight while you are also in direct sunlight. think of it like putting a magnifying glass above you and you're in the bright pinpoint of light. You're having multiple "layers" of sunlight shining on you.
This was actually a problem here in Las Veg... | [
"Glass coated with a low-emissivity substance can reflect radiant infrared energy, encouraging radiant heat to remain on the same side of the glass from which it originated, while letting visible light pass. This often results in more efficient windows because radiant heat originating from indoors in winter is refl... |
I have heard that what is now the Sahara desert used to be much smaller/wetter. Was there ever a trans-Saharan trade route in antiquity? | Yes. The Garamantes had a string of cities in the western Sahara, based on "fossil water" from caverns, left from the days of the Green Sahara. This would be south of modern Tunisia & Libya. They were at their height 500 BC to 700 AD, or about 1200 years. They warred with the Romans, used an early version of the Tuar... | [
"After the Sahara became a desert, it did not present a totally impenetrable barrier for travelers between north and south because of the application of animal husbandry towards carrying water, food, and supplies across the desert. Prior to the introduction of the camel, the use of oxen, mule, and horses for desert... |
- what is the difference between linear polarized light and circular polarized light? | I think it is beast to think circular polarization as two linearly polarized light together.
[Here are few good animations](_URL_0_)
By combinign two linearly polarized light at 90° angles (red and green) you get circular polarized light (cyan). | [
"There is a relatively straightforward way to appreciate why a polarizer which creates a given handedness of circularly polarized light also passes that same handedness of polarized light. First, given the dual usefulness of this image, begin by imagining the circularly polarized light displayed at the top as still... |
how come humans could easily move and migrate when the environments change to survive yet animals don't? | It's because humans have solved the logistical problems owing to bigger brains. | [
"Population confined to one geographic location does not have a simple option of migration- such as animals that live in cold regions at the tops of low-lying mountains. These animals are in habitats that will run out as climate change increases and global warming becomes more impacted.\n",
"Animals move for a va... |
Good overview texts on revolutions in general: any recommendations? | One of the better anthologies on revolutions is the third edition of *Revolutions: Theoretical, Comparative, and Historical Studies* edited by Jack Goldstone. The anthology contains excepts from various theorists trying to answer just those questions and is an introduction to the various explanations and models. Gold... | [
"Trimberger's book was favorably received by revolutions scholars, who had focused so much on the \"Great Revolutions\" of France, Russia, and China, but had largely neglected the so-called \"revolutions from above\".\n",
"The Anatomy of Revolution is a 1938 book by Crane Brinton outlining the \"uniformities\" of... |
i know things have certain frequencies but do humans do as well? and what happens when humans are vibrated at that frequency? | Everything has a (one or more) resonance frequency. Usually we refer to the spine and skeletal system, but the human body is very complex and [every organ has its own frequency](_URL_0_).
What happens when you meet that frequency?
For the skeletal-spine-muscle system,
> At the resonant frequency there is maximum... | [
"Any vibrating thing produces vibrations at a number of frequencies above the fundamental pitch. These are called overtones. When the overtones are integer multiples (e.g., 2×, 3× ... 6× ... ) of the fundamental frequency (called harmonics), then - neglecting damping - the oscillation is periodic—i.e., it vibrates ... |
what is mega and how do you use it? | Simply put, imgur for files(With more privacy) | [
"Mega (stylized in uppercase as MEGA) is a cloud storage and file hosting service offered by Mega Limited, an Auckland-based company. The service is offered primarily through web-based apps. Mega mobile apps are also available for Windows Phone, Android and iOS.\n",
"Mega is a unit prefix in metric systems of uni... |
why is the international community mostly apathetic when a government kills its people with conventional weapons, but loses it's mind when chemical weapons are involved? | 2 reasons
First, after WWI the horrible injuries caused by chemical weapons caused people to realize that there were things that even in war should not be permitted. The industrialized nations (the ones with the ability to make them) agreed to ban them & to punish those who used them. As more nations developed the s... | [
"When people call a targeted killing an \"assassination,\" they are attempting to preclude debate on the merits of the action. Assassination is widely defined as murder, and is for that reason prohibited in the United States ... U.S. officials may not kill people merely because their policies are seen as detrimenta... |
if dogs can smell so much better than people, how is it that they can stick their noses deep in shit when i need to be upwind with a 10 foot pole? | Shit is like a fine wine.
Your first sip of wine maybe sour and a little revolting, but as you learn to separate the flavors, and really dive deep into the complex levels of a wine's flavor profile it opens you up into a new world.
Similarly, dogs smell shit in the same way, they need to really fill their nostrils wi... | [
"The dog has mobile nostrils that help it determine the direction of the scent. Unlike humans, the dog does not need to fill up his lungs as he continuously brings the odor into his nose in bursts of 3-7 sniffs. The dog's nose has a bony structure inside that humans don't have, which allows the air that has been sn... |
if the flu mutates so rapidly, why do we experience similar symptoms every time we get it? | Not all parts of the virus mutate at the same rate. The parts necessary to keep the virus functioning are going to be conserved from one generation to the next. Other parts are more free to change, because there may be some flexibility in the way the virus uses them.
The proteins used to attach to host cells and get... | [
"The American Center for Disease Control and Prevention (CDC) agrees that the \"spread of novel H1N1 virus is thought to occur in the same way that seasonal flu spreads. Flu viruses are spread mainly from person to person through coughing or sneezing by people with influenza.\" The CDC also says that a person may b... |
What/when was the last sail-powered warship to be commissioned? | The first steam-powered "battle ships" came into play in the 1850's and most still had sails. The last real usages of purely sail-powered naval vessels were likely the Crimean War and the American Civil War.
Specific ship? The HMS Warrior, likely... at least the most well known ship of the era in which you are asking... | [
"These ships were the Royal Navy's first privately designed warships for many years. They were also the first design to enter service with the Royal Navy to be solely powered by gas-turbine engines, with two Rolls-Royce Tynes for cruising and two Rolls-Royce Olympus for high speeds arranged in a combined gas or gas... |
what's actually happening in a freshly poured guinness that makes it look like the bubbles flow downwards? | It's because the bubbles on the outside of the glass stick to the glass and rise slowly due to friction. Bubbles in the middle can go up unimpeded. That happens with all beer. Why is Guinness (and Boddington's) special?
Instead of CO2, if you charge a beer with nitrogen the bubbles are so small and plentiful that this... | [
"When Guinness is poured, the gas bubbles appear to travel downwards in the glass. The effect is attributed to drag; bubbles that touch the walls of a glass are slowed in their travel upwards. Bubbles in the centre of the glass are, however, free to rise to the surface, and thus form a rising column of bubbles. The... |
What is the threshold for the amount of flesh or bone loss regarding regrowth? Why couldn't a human simply regrow a lost digit or limb? | The main problem in regrowing a limb is that there are a slew of genes that regulate the process that have to be "turned on and off" in a coodinated manner in order to generate the arrangement of cells and tissues in an arm/leg/tail (last one included for my fellow salamander and newt peeps). [Limb development](_URL_1_... | [
"The regrowth of lost tissues or organs in the human body is being researched. Some tissues such as skin regrow quite readily; others have been thought to have little or no capacity for regeneration, but ongoing research suggests that there is some hope for a variety of tissues and organs. Human organs that have be... |
How was the wavelength of light originally measured? | Thomas Young's double slit experiment was perhaps the first, he saw an interference pattern of light passing through two slits onto a screen. The periodicity of the interference pattern is related to the wavelength and the geometry of the system. | [
"One of the most basic tasks in spectroscopy is to characterize the spectrum of a light source: how much light is emitted at each different wavelength. The most straightforward way to measure a spectrum is to pass the light through a monochromator, an instrument that blocks all of the light \"except\" the light at ... |
why is it uncomfortable to stand with both legs straight for extended periods of time? | Muscles in the legs massage the veins when you're walking. This helps the veins return blood back to the heart.
If you're standing still all your muscles are tensed to keep you upright. This means they're not in a cycle of contraction and relaxation, like when you're walking. No cycle, no vein massage, which in turn l... | [
"A person standing upright begins to lean to one side. The postural muscles that are closely connected to the vertebral column on the opposite side will stretch. The muscle spindles in those muscles will detect this stretching, and the stretched muscles will contract to correct posture.\n",
"After sitting for a l... |
How come there was a Caucasian Iberia and Albania? Did the two have anything to do with the naming of the modern day country of Albania and peninsula? | European Iberia is named after Ebro River in Spain, itself of Celt-Iberian origin (reconstructed *Ibēr). Caucasian Iberia was probably related to Old Armenian Վիրք 'Virk' referring to Georgians. More specifically Ancient Greek writers called Eastern Georgians Iberians, with the Western ones called Colchians (an exonym ... | [
"Iberia (Georgian – იბერია, and Greek: ), also known as Iveria (), was a name given by the ancient Greeks and Romans to the ancient Georgian kingdom of Kartli (4th century BC – 5th century AD), corresponding roughly to the eastern and southern parts of the present day Georgia. The term Caucasian Iberia (or Eastern ... |
[Biology] How big would an ant have to be to lift an average sized car? | There are two potential answers. An organisms weight grows in proportion to its volume, so if you go with the 'an ant can lift x times its body weight' answer, then you would need an ant approximately the weight (and presumably size) of an Alaskan Malamute.
However; since strength correlates with the cross sectional ... | [
"Many insects are able to lift twenty times their own body weight like Rhinoceros beetle and may jump distances that are many times greater than their own length. This is because their energy output is high in relation to their body mass. \n",
"The giant anteater can be identified by its big size, elongated muzzl... |
how do green screens work? what sort of software do you need to mess around with green screens? | Any decent video editing software has a green screen function, iMovie which comes with Mac's for instance had this ability. The screen doesn't have to be green, it's just that green and blue are not close to skin color. You just tell the video editing software to remove a certain color and replace it with something els... | [
"Some green screen displays were furnished with a particularly full/intense phosphor coating, making the characters very clear and sharply defined (thus easy to read) but generating an afterglow-effect (sometimes called a \"ghost image\") when the text scrolled down the screen or when a screenful of information was... |
how did they manage to make quaaludes completely disappear with all the genius chemists in this world? is there ingredients that are impossible to find or even synthesize? | The main chemical in these drugs, methaqualone, is neither impossible nor even that difficult to synthesize. A few procedures don't actually require anything you wouldn't find in a well-stocked high school or college chemistry department, however they take a longer period of time and produce a lower yield. I'm speaking... | [
"Despite several attempts, unbibium has not yet been synthesized, nor have any naturally occurring isotopes been found to exist. There are currently no plans to attempt to synthesize unbibium. In 2008, it was claimed to have been discovered in natural thorium samples, but that claim has now been dismissed by recent... |
why do humans perceive time at the 'rate' that we do? does time even have a natural 'rate', or is it just a property of consciousness and our perception? | Perception of time is relative. If you ever get into a car accident or other life-or-death scenario, you will know what I mean.
Time, on its own, has no rate, because there are no units to define the rate. We defined the rate to be one second per second, or a year per year. Our units are fairly arbitrary (excepting mo... | [
"Time perception is a field of study within psychology, cognitive linguistics and neuroscience that refers to the subjective experience, or sense, of time, which is measured by someone's own perception of the duration of the indefinite and unfolding of events. The perceived time interval between two successive even... |
What demands would the Central Powers have demanded if they had won WWI | From the sidebar: Keep in mind that this forum is for asking questions about what did happen, not what could have happened had something gone differently. For those types of questions, check out [/r/historicalwhatif](_URL_0_). | [
"One of the conditions of Marshall Aid was that the nations' leaders must co-ordinate economic efforts and pool the supply of raw materials. By far the most critical commodities in driving growth were coal and steel. France assumed it would receive large amounts of high-quality German coal from the Ruhr as reparati... |
how does printscreening exactly work? | Yes, there is! It's usually called the frame buffer.
This is a chunk of memory containing a bitmap image that the video hardware continually reads and sends out to the display. Other programs write to this chunk of memory to edit what picture is being sent.
Being that it's just a chunk of memory, other programs can r... | [
"Screenprinting may be adapted to printing on a variety of materials, from paper, cloth, and canvas to rubber, glass, and metal. Artists have used the technique to print on bottles, on slabs of granite, directly onto walls, and to reproduce images on textiles which would distort under pressure from printing presses... |
why do you think you look one way when looking in a mirror (good) and then worse when looking at pictires/front facing camera (bad)? | The others have mentioned the reverted image, and to an extent that is correct.
However, when you begin to look at cameras, the focal length of the camera can affect what you look like, by exaggerating some of your features etc.
Here is a pretty cool [example](_URL_0_)
| [
"This psychological effect is often used in the cinema, where an actor will be shown apparently looking at himself or herself in the mirror. What viewers see is different from what the actor sees, because the camera is not right behind the actor, but the position of the actor is often chosen so that his or her imag... |
Early Christianity and social militancy | Hm. This is a theory I had never heard before. From what I've heard of the early Christian communities they seem to have been expecting Jesus' imminent return. So I can't see them necessarily taking up arms like your book suggests. However, I suppose it can't be ruled out in some cases. Early Christianity was by no mea... | [
"The early Christians opposed the deterministic views (e.g., fate) of Stoics, Gnostics, and Manichaeans that were prevalent in those first four centuries. Christians championed the concept of a relational God who interacts with humans rather than a Stoic or Gnostic God who unilaterally foreordained every event (yet... |
Current through magnet | If the current were enough to heat the magnet above the "Curie Point", then it would lose all magnetism. If it were significant current *below* that temperature, it would change the magnetism to closed magnetic circuits *within* the bar, and not much magnetism detectable beyond the outside of the metal. Even less cur... | [
"A magnet induces circular electric currents in a metal sheet moving through its magnetic field. See the diagram at right. It shows a metal sheet \"(C)\" moving to the right under a stationary magnet. The magnetic field \"(B, green arrows)\" of the magnet's north pole \"N\" passes down through the sheet. Since the ... |
why emotions from suppressed sources feel much stronger than regular emotions | Your sister makes your life worse, by continuing to piss you off over a period of years. That has a much greater effect on you than some random annoyance in your life that is perhaps only going to happen once. It is oppressive to know that you will continue to be troubled by your sister for some indefinite time to co... | [
"“In a prior paper, we found that emotion plays a big role in which New York Times articles make the most emailed list. But interestingly, we found that while articles evoking more positive emotions were generally more viral, some negative emotions like anxiety and anger actually increased transmission while others... |
During capillary action the average gravitational potential energy of the molecules increases. Where does that energy come from? | I'm going to simplify this a bit but consider the attraction of water to the capillary walls and let us call this "capillary energy". If the water climbs up the capillary walls then you could say the capillary energy has been transduced into gravitational potential energy.
You can not get any work from this capillary... | [
"Gravitational energy is the potential energy associated with gravitational force, as work is required to elevate objects against Earth's gravity. The potential energy due to elevated positions is called gravitational potential energy, and is evidenced by water in an elevated reservoir or kept behind a dam. If an o... |
how do some teenagers/children show great maturity and adult like qualities even if their frontal lobes aren't fully developed? | Well in this case, 'adult' is a bit of a misnomer, as I'm assuming you mean > 25 by the term (that's when your frontal lobe stops developing).
I'll answer your question with a question. How do some adults show great immaturity if their frontal lobes are fully developed? The answer is, everybody's different. Some peop... | [
"While many people believe that the brains of emerging adults are fully developed, they are in fact still developing into their adult forms. Many connections within the brain are strengthened and those that are unused are pruned away. Several brain structures develop that allow for greater processing of emotions an... |
What happened at the battlefields shortly after major WWI battles such as the Somme, Verdun, etc? | > what exactly happened on those parts of the front once these months long battles were over? Did these battles just fizzle out to where both sides just sat in their trenches from exhaustion?
In the case of the Somme, there was some small scale skirmishing here and there during the winter of 1916, but starting in Fe... | [
"The Second Battle of the Somme of 1918 was fought during the First World War on the Western Front from late August to early September, in the basin of the River Somme. It was part of a series of successful counter-offensives in response to the German Spring Offensive, after a pause for redeployment and supply.\n",... |
why does australia choose to process illegal asylum seekers offshore instead of onshore? | I'm sure it's more complicated than this, but afaik it is because a large number of people seeking asylum were arriving illegally via boats from South East Asia. The understanding was that if they reach Australian soil, they have 'made it' and will be processed through.
This led to a lot of dangerous situations as peo... | [
"After the election, the government continued with its hard line on unauthorised arrivals of asylum seekers. Legislation was developed to excise certain islands from Australia’s migration zone meaning that if asylum seekers landed on an excised island, Australia was not required to provide access to the Australian ... |
When the French colonized North America, why did they settle so far north? | Two very important things to remember is that during the time that the French were starting to explore and colonize North America, 1. explorers like Jacques Cartier were trying to find passage to China because, 2. the country which commissioned the explorers wished to begin trade with established countries/exploit reso... | [
"The French colonized northern areas, moving in along the St. Lawrence River from early trading posts among Algonquian-speaking tribes on the Atlantic Coast; they founded Quebec in 1608. When Samuel de Champlain explored the St. Lawrence River, he claimed the region French Canada as including Western New York. The ... |
how do we know a cats likes cat food, dogs like dog food? | It's not a matter of what they like. Cats and dogs have different nutritional needs. So, you design a food with the nutritional value you are looking for, then make it appeal to the taste of that type of animal.
Also, cats are obligate carnivores, they *must* only eat meat. Dogs are kinda omnivores, or even scavenge... | [
"Cats are obligate carnivores, though most commercial cat food contains both animal and plant material supplemented with vitamins, minerals and other nutrients. Cat food is formulated to address the specific nutritional requirements of cats, in particular containing the amino acid taurine, as cats cannot thrive on ... |
When did common people start caring about what the exact time was? | I bet it has to do with religious rituals | [
"The development of railway networks in North America in the 1850s, India in around 1860, and in Europe, prompted the introduction of standard time influenced by geography, industrial development, and political governance.\n",
"The history of standard time in the United States began November 18, 1883, when United... |
How were the first trees cut down? | I think you're underestimating how sharp an edge you can achieve with stone! [Early handaxes](_URL_4_) were indeed used for cutting (e.g. to butcher animals), and by the middle stone age (Mesolithic/Epipalaeolithic) people were producing ["microlith" blades](_URL_0_) which had an extremely sharp cutting edge. So much s... | [
"Felling of large trees such as redcedar before the introduction of steel tools was a complex and time-consuming art. Typically the bark was removed around the base of the tree above the buttresses. Then some amount of cutting and splitting with stone adzes and mauls would be done, creating a wide triangular cut. T... |
why is obama visiting saudi arabia to give condolences when it is widely known saudi arabia is barbaric in its practices of torture, arbitrary judicial murders, street beheadings and flogging? | Because Saudi Arabia is an important ally, has a lot of oil and has a lot of influence in the region. Those are all very important reasons for the US to keep the political relationship with SA good and visiting at times like this keeps that political relationship good.
Secondly, if you want to chance all of those th... | [
"Mohammed al-Nimr, the cleric's brother, blamed US President Barack Obama for failing to use his influence with the Saudi government to prevent his brother's execution. He said: \"We asked very clearly for the American president to intervene as a friend of Saudi Arabia — and the Americans did not intervene\".\n",
... |
- why does a community need to secure the right to create its own broadband? why can't they just do it? | Also, the cities often don't own the poles, companies like AT & T do. Thus, the city needs permission from whoever owns them to run cables and stuff on the poles. (I'm not an expert, I just found this out from people that worked on getting google fiber to come to their city). | [
"As private investors do not always have the strongest incentives to deploy broadband in rural and underserved communities at an affordable price, states and local leaders should be allowed to step in to provide affordable broadband services that will meet their residents' needs.\n",
"BULLET::::- Rural access: So... |
why are small animals, even when bred in captivity, still afraid of human interaction? | Animals tend to run from everything. Its safer than getting into a fight. Only when they've been around another species for a very long time do they know they don't have to flee.
When you live in big cities for example, birds aren't typically afraid of people. They've come to learn we are not going to hurt them, and t... | [
"Behavior of animals in captivity Captive animals, especially those not domesticated, sometimes develop abnormal behaviors. One type of abnormal behavior is stereotypical behaviors, i.e. repetitive and apparently purposeless motor behaviors. Examples of stereotypical behaviors include pacing, self-injury, route tra... |
if my parents had sex to conceive me 3 hours earlier than they did, would i have then been born 3 hours earlier? | There's more of a chance of you not being you than anything else. | [
"A Western Australian based study followed 150 first-time mothers and found that most of the teenagers were having sex again within 3 months of the birth of their babies, and in total 47 were pregnant again within 2 years. Two were said to be pregnant just 6 weeks after their first birth.\n",
"On the other hand, ... |
how is it possible that an open-source encryption program is safe? also why is it that 2048 bit encryption is currently unbreakable? | The nice thing about public key cryptography is that knowing how it's made doesn't make it less secure. The algorithm isn't secret, the keys are.
Now, as for the bit length: imagine that I asked you for a password, and it was a number, and you decided to guess it. If you know it's a number between one and ten, then it... | [
"The majority of publicly available encryption programs allow the user to create virtual encrypted disks which can only be opened with a designated key. Through the use of modern encryption algorithms and various encryption techniques these programs make the data virtually impossible to read without the designated ... |
What was the political landscape like in England at the time of William the Conquerer's invasion, and what prompted him to invade when he did? | This is one of those questions that has both relatively succinct, and incredibly long answers.
In short, he invaded when he did because the King of England, Edward, had just died and left no heir or instructions for his succession. This left three potential kings, one of whom was very quickly elected as king by the An... | [
"Although William's main rivals were gone, he still faced rebellions over the following years and was not secure on his throne until after 1072. The lands of the resisting English elite were confiscated; some of the elite fled into exile. To control his new kingdom, William granted lands to his followers and built ... |
- how does australian football work? | Ok.
Each team is trying to put the ball through the posts. The height at which the ball passes between the posts is not important.
You get 6 points for a 'goal' (between the two taller middle posts) and 1 point for a 'behind' (between one of the tall posts and one of the smaller posts on the right or left)
The ball... | [
"Australian rules football, officially known as Australian football, or simply called Aussie rules, football or footy, is a contact sport played between two teams of eighteen players on an oval-shaped field, often a modified cricket ground. Points are scored by kicking the oval-shaped ball between goal posts (worth... |
what exactly would it mean for us if a particle, other than a photon, was able to travel at the speed of light or faster ? | I thought CERN had already accomplished obtaining particles that moved faster than light? No one talks about it much, so I'm guessing not a whole lot changed | [
"Current commonly accepted physical theories imply or assume the photon to be strictly massless. If the photon is not a strictly massless particle, it would not move at the exact speed of light, \"c\", in vacuum. Its speed would be lower and depend on its frequency. Relativity would be unaffected by this; the so-ca... |
if someone is wrongfully imprisoned for a period of time and then released after proven innocent, how is their compensation calculated? | Depends on the state. [Each state has different statutes governing this] (_URL_0_). Also, several states have no statutes at all, meaning that if you get wrongfully convinced there, you have no automatic right to recourse. I believe (but am not 100% on it) that you can take the state to civil court, but obviously, many... | [
"Imprisonment is not just a pretty good proof of guilt, but can frustrate the contract if for more than a few months, which would bring the contract to an end without the need for procedure or compensation. Being held on remand could justify a short spell of suspension on full pay, but if this is without pay or for... |
If quartz oscillates at an exact frequency, how can an atomic clock be any more accurate? | All clocks have sources noise at some fundamental level and we have a variety of ways of measuring the stability. For crystals, there are a [number of effects](_URL_1_) which alter the frequency on both short timescales and long timescales. A good way to think of short timescales is with the precision of a tick of a wa... | [
"Due to aging and environmental factors (such as temperature and vibration), it is difficult to keep even the best quartz oscillators within one part in 10 of their nominal frequency without constant adjustment. For this reason, atomic oscillators are used for applications requiring better long-term stability and a... |
How was the US government able to muster enough support to pass the 16th Amendment allowing taxation of income? | At the time of the Amendment's passage, tariffs on imported goods and excise taxes on produced goods were the primary sources of government revenue. The burden of the tariffs fell disproportionately on the rural areas of the country (a much larger percentage of the population than today), since it raised the prices of ... | [
"Though the constitutional amendment to allow the Federal government to collect income taxes was proposed by President Taft in 1909, the 16th Amendment was not ratified until 1913, just before the start of the First World War. In 1913 the first edition of the 1040 form was introduced. A copy of the very first IRS 1... |
why, when parked in a parking garage / building, does your car bounce up and down when another car drives by on the same floor? | A lot of those garages are held together by gravity. They're big concrete 'plates' resting on top of one another. So when you put a lot of weight on one side of a plate, it tips just a little bit and lifts up the vehicles on the other side. | [
"Automobiles usually have parking brakes on the rear wheels. If the rear axle is jacked off the ground with only the parking brake set, the vehicle may roll on the front wheels and fall. Chocking the front wheels prevents this mishap.\n",
"The cars are typically placed on a square lattice that is topologically eq... |
why are there no national grocery stores | There are.
_URL_0_
Kroger bought several grocery store chains. Because people don't like change, and like to think they are sponsoring local brands/companies, Kroger kept the local names of each chain. | [
"Green grocery markets are places where people supply themselves with agricultural products that are of local origin and from municipalities from the eastern and central portions of the country as well. The current green markets don't satisfy the necessities of many people, so there is a need for building more of t... |
when metal rusts, does that mean we can never use it again? could we completely run out of metal? | You can reverse rusting through melting it down and introducing chemical catalysts to separate the oxygen. However only certain metals rust into a dirty pile of particulates.
When iron rusts, it's oxidizing, and because of the size difference between unrusted and rusted molecules, that causes the metal to flake off an... | [
"For iron rust to occur the metal has to be in contact with oxygen and water, although chemical reactions for this process are relatively complex and not all of them are completely understood. It is believed the causes are the following:\n",
"Rust is a mixture of iron(III) oxide and oxide-hydroxide that usually f... |
why do people call for the ceo of a company to resign when something publicly bad happens to said company? | Have you ever seen a sign saying "parents are responsible for their children"? If the kids break a window, the parents are responsible for it.
It's the same with the CEO. It's the person responsible for the company. Good or bad. It's their fault if a racist commercial is approved and aired by the company, it's their f... | [
"Is a company against a Replacement of a leader, could this end in a situation, where the declining process will be continued. As result qualified employees resign, the organisation discredits and the resources left will run out as time goes by.\n",
"They concluded that the decision-making of firing a CEO is base... |
Are personal computers finite state machines? | A FSM is a machine with a finite amount of states, meaning that it can not represent infinity. This is true for your computer since it only contains a finite amount of data, whether that is 1 tb or a trillion tb, it is finite. Thus, a computer IS a finite state machine, it will run out of states given enough time. Howe... | [
"BULLET::::- Deterministic finite automaton (DFA): Also called a finite-state machine. All real computing devices in existence today can be modeled as a finite-state machine, as all real computers operate on finite resources. Such a machine has a set of states, and a set of state transitions which are affected by t... |
Did public executions have mass psychological effects? | I am not sure if there have been similar cases of dehumanisation and mental breakdowns in a similar fashion as those suffered by those who took part in the Final Solution. However, there have been some people who have pointed at the drastic decrease of support for public executions and brutal punishments as society 'pr... | [
"Executions without trials and other forms of \"popular justice\" were harshly criticised immediately after the war, with circles close to Pétainists advancing the figures of 100,000, and denouncing the \"Red Terror\", \"anarchy\", or \"blind vengeance\". The writer and Jewish internee Robert Aron estimated the pop... |
why do we need credit cards, if debit cards can have overdrafts? | i'd rather pay 22% on that pack of gum than $35 for an overdraft | [
"The Washington Post columnist pointed out that debit card issuers could notify customers electronically, allowing them to avoid the overdraft fees. The article contended that \"financial institutions don't want to change the status quo because they make good and easy money off their own customers' mistakes and irr... |
how do royalties work with cover songs? | When Tool covers No Quarter from Led Zeppelin, how is that handled? Dave Matthews Band covers a ton of songs live, what are they responsible for? | [
"ASCAP collects licensing fees from users of music created by ASCAP members, then distributes them back to its members as royalties. In effect, the arrangement is the product of a compromise: when a song is played, the user does not have to pay the copyright holder directly, nor does the music creator have to bill ... |
Did any scientists who were asked to work on the Manhattan Project refuse? If so, what happened to them? | Yes, because many people who were recruited for the project could not be told what it was until they signed on the dotted line. Security concerns meant most people didn't know what they were signing up for, only that it was crucial to winning the war.
Stephane Groueff, in *Manhattan Project: The Untold Story of the Ma... | [
"The Committee was established in the wake of the \"Szilárd petition\" (July 1945) to United States president Harry S. Truman opposing the use of the atomic bomb on moral grounds, which was signed by 68 scientists who had worked on the Manhattan Project. A majority of scientists working on the Manhattan Project did... |
Slavic migration | Take a look at this [thread](_URL_0_), as there are a few detailed comments there on what we know about the Slavs from the earliest literary sources (all of which place them in Eastern Europe close to the Danube River by the way) and the linguistic/archaeological evidence. There is very little information on why some S... | [
"The migration of Slavic peoples from their homeland began in roughly the late 4th to early 5th century, as Germanic peoples started moving into the territory of the Roman Empire. The migrations were stimulated by the arrival of Huns into Eastern Europe. The Germanic peoples subsequently fought for control over ter... |
why does it hurt so much when you bang the top of your kneecap? | Our joints have loads of nerves to take messages back and forth between our spine and extremities. These nerves are vulnerable and relatively exposed because the flesh and bone that would otherwise protect them would restrict movement. The result is it hurts like a Motherf**ker when you bang them. | [
"Kneecapping is a form of malicious wounding, often as torture, in which the victim is injured in the knee. The injury is typically inflicted by a low-velocity gunshot to the knee pit with a handgun. The term is considered a misnomer by medical professionals because only a very small minority of victims suffer dama... |
oled displays: samsung vs apple | Apple can toy with software and graphics a little but in the end they’re the same. Neither display really has any additional capability than the other. Apple also has 3D Touch Samsung doesn’t. But apple buys a Samsung screen and then calls it something retina and that makes it apple... and as the previous poster above ... | [
"Universal Display's OLED screens currently feature in Samsung's Galaxy S, S II and S III, S IV and S V smartphones. The Galaxy S3 sold 10 million units in the first three months after its launch in April 2012. Also, their Galaxy Note has sold 10 million units since launch.\n",
"The Samsung Galaxy SL has a SuperC... |
why do doctors pop/drain cysts? | They do that. That's actually the way you remove a cyst. You open, remove the cyst and it's envelope (the sac) so there is no recurrence. [Read this](_URL_0_). However, it is not always possible to take all of it out and therefore it might grow back. | [
"Genitoplasties are plastic surgeries that can be carried out to repair, restore or alter vulvar tissues, particularly following damage caused by injury or cancer treatment. These procedures include vaginoplasty which can also be performed as a cosmetic surgery. Other cosmetic surgeries to change the appearance of ... |
how can we detect the difference between a missile test launch vs one aimed at say washington d.c? | Ballistic missiles have that name because they follow a "ballistic" trajectory. They fly on a curved path that's fairly straightforward to calculate.
A launch from North Korea aimed at a US city would have a very specific launch angle and velocity that should be apparent when the missile is initially detected on rada... | [
"The system's radar is referred to as EL/M-2084. It detects the rocket's launch and tracks its trajectory. The BMC calculates the impact point according to the reported data, and uses this information to determine whether the target constitutes a threat to a designated area. Only when that threat is determined, is ... |
Is it known if any other species have an inner monologue? How does the human mind recognize the inner monologue as its own thoughts, and not as external stimuli? | Inner dialogue is produced by generating language and not articulating. The understanding of language takes places in the left temporal lobe ([Wernicke's area](_URL_1_)), while the production of language takes places in conjunction with your left frontal lobe ([Broca's area](_URL_2_)) and motor cortex.
Inner dialog... | [
"Not everyone reports experiencing an internal monologue, and most people report experiences that do not involve an internal monologue at least some of the time. This is particularly prevalent among children, and has been cited as evidence for the \"language of thought\" hypothesis, which posits an underlying langu... |
What did the people of Athens, Greece think about the Peloponnesian War as it was happening? | > What did they really think?
The short answer is that we will never know.
Our main sources for the events of the Peloponnesian War are the contemporary historical accounts of Thucydides and Xenophon. Both authors counted among the leisured elite of Athenian society; indeed, before his exile, Thucydides would have ... | [
"Many historians consider these actions to be only a partial explanation for the start of Peloponnesian War between Sparta and Athens. They argue that the underlying cause was the growing resentment of Sparta and its allies at the dominance of Athens over Greek affairs. The war lasted 27 years, partly because Athen... |
why aren't dna samples taken at birth? would that not help future criminal cases by a grand margin? | Because its your dna in your body. And you have the innate right to deny others access to your body. | [
"CNN reported that DNA testing was performed to expedite parental verification and ensure reunification with verified parents, without details being reported as to whether consent has been asked. Human rights advocates have criticized that migrant children, some as young as two months old, cannot give their consent... |
How did the Nazis/Hitler feel towards people of African descent? | I have [written before about the lives and experiences of Black people in Nazi Germany](_URL_1_) with some interesting follow-up discussion.
My answer almost exclusively focuses on Black people in Germany and the Afro-German community. There is more to be said, especially about Black POWs and Black people in France bu... | [
"The Nazis promoted xenophobia and racism against all \"non-Aryan\" races. African (black sub-Saharan or North African) and Asian residents of Germany and black prisoners of war, such as French colonial troops and African Americans, were also victims of Nazi racial policy. When the Nazis came to power, hundreds of ... |
why is it that most measurements have been standardized but not others (ie. hands on horses, bushel of apples) | In general use, standardized measurements are already the norm. More specialized measurements (barrel of oil, bushel of apples) are mainly used in industry, and are mainly a legacy issue (people don't feel like changing how the industry operates, so they keep on using barrels of oil as a measure). | [
"Most of the units of measure have been adapted in one way or another since the Norman Conquest (1066). The units of linear measure have changed the least – the yard (which replaced the ell) and the chain were measures derived in England. The foot used by craftsman supplanted the longer foot used in agriculture. Th... |
Does name of the modern-day country of Romania have any connection to the Western term for the Byzantine Empire circa the later Early Middle Ages? | Probably not. Although the Southern and Eastern parts of Romania were deeply influenced by Byzantium during the high middle ages (in terms of bureaucracy, forms of leadership, etc.), and although the feudal states that would make up Romania in the later 19th century have traditionally defined themselves as Orthodox, an... | [
"The Empire of Romania (), more commonly known in historiography as the Latin Empire or Latin Empire of Constantinople, and known to the Byzantines as the \"Frankokratia\" or the Latin Occupation, was a feudal Crusader state founded by the leaders of the Fourth Crusade on lands captured from the Byzantine Empire. I... |
why with one click i can change highlighted text to italics but i have to completely retype something if i want it to be capitalized. | TIL: Shift + F3 | [
"There are many designs. With both italics and boldface, the emphasis is correctly achieved by swapping into a different font of the same family; for example by replacing body text in Arial with its bold or italic style. Professional typographic systems, including most modern computers, would therefore not simply t... |
how does a shock from a taser compare to a shock from a 120v residential circuit? | The taser has a high voltage (2000V during pulsing, but far more during the initial arc) but a very low current ( < 500mA)
A home outlet is the inverse, relatively low voltage but a high peak current (10-20A usually)
Current is the killer here, more amps means more power and more damage. Voltage helps the power cros... | [
"Manufacturers' instructions and manuals shipped with the products state that a half-second shock duration will cause intense pain and muscle contractions, startling most people greatly. Two to three seconds will often cause the recipient to become dazed and drop to the ground, and over three seconds will usually c... |
Who was more responsible for the Cuban Missile Crisis of 1962? NATO (USA) or the USSR. | Well, I'm drawing from Khrushchev's memoirs here, so not the most unbiased source.
However, I think it's one worth hearing, as we in the west rarely get the Soviet perspective on events of the time.
In the mid-late 1950s, the US started basing medium range nuclear missiles in Turkey. This was worrying to the USSR not... | [
"The Cuban Missile Crisis (October Crisis in Cuba) was a confrontation between the United States and the Soviet Union over nuclear missiles that were deployed in Cuba and Turkey. The Russian missiles were placed both to protect Cuba from further attacks by the United States after the failed Bay of Pigs Invasion, an... |
Why did WWII aircraft carriers lack the angled decks now found in every modern carrier, and why were such carriers not designed and built during the war? | Angled decks were not used on WWII-era carriers because they had not yet been developed; they were not developed because they were not necessary.
All carriers designed before or during WWII used an 'axial' (straight) deck design (barring a few early experiments into multi-level flight decks, like that seen on the *Co... | [
"The angled flight deck was invented by Royal Navy Captain (later Rear Admiral) Dennis Cambell, as an outgrowth of design study initially begun in the winter of 1944–1945. A committee of senior Royal Navy officers decided that the future of naval aviation was in jets, whose higher speeds required that the carriers ... |
During meiosis do chromasomes cross over only at specific points? For example is it possible to cut a gene in half during the crossing over? | Crossovers definitely do occur within genes. As long as there is not a single nucleotide lost or added when this happens, then nothing is wrong. If such a thing occurs it is called an *indel* and is either an insertion or deletion of nucleotides within the gene. If this happens with one or two nucleotides it can have s... | [
"During normal mitosis, sister chromatids separate into two identical daughter cells. In meiosis is a diploid cell (2N) duplicates its DNA once and undergoes two rounds of cell division to produce four haploid (1N), germ cells that promotes the recombination of large expanses of chromosomal DNA, potentially similar... |
why, if the halves of the brain are "in charge" of different things, do patients with one half of their brain removed not completely lack the characteristics of the side they lost? | How many patients actually get half their brain removed? Not many. A much more common medical procedure is to cut, partially or in whole, the corpus collosum that connects the half. Some people also just manage to get born without a proper corpus collosum.
There have been studies and in particular Kim Peek is well kn... | [
"After the right and left brain are separated, each hemisphere will have its own separate perception, concepts, and impulses to act. Having two \"brains\" in one body can create some interesting dilemmas. When one split-brain patient dressed himself, he sometimes pulled his pants up with one hand (that side of his ... |
why did people name objects with 2000 in some cartoons and comics? | Many classic cartoons were made in the 1950s and 1960s. Around then, the year 2000 sounded like an amazing future. So the number 2000 represented futuristic advanced technology. | [
"The names he invented for them sometimes appear in dictionaries, and serve as convenient terminology occasionally used by cartoonists and critics. A 2001 gallery showing of comic- and street-influenced art in San Francisco, for example, was called \"Plewds! Squeans! and Spurls!\"\n",
"\"We wondered why people we... |
When you light a propane torch, why does the fire not also ignite the gas inside the canister? | Propane requires oxygen to burn. It only gets enough when it exits the nozzle into the atmosphere. The velocity and pressure of the gas coming out blocks any significant amount of oxygen from getting into the canister. | [
"However, propane produces heat, which (when firing for an extended period at high rates of fire) can cause burns if improperly handled. It can also be a fire hazard: the Tippmann C3 releases small amounts of flames from the vents in the combustion chamber and out of the barrel when firing. If a marker develops a l... |
Is there a way I can find out if anyone in my family died in WWI or WWII? | Hello there! As your question is related to looking for identification/information regarding military personnel, our [Guide on Military Identification](_URL_0_) may be of use to you. It provides a number of different resources, including how to request service records from a number of national agencies around the world... | [
"The Shobrooke 1914–1918 War Memorial holds the names of 25 men who lost their lives in World War One, the list includes the names of three brothers from the Horwell family, all three died within 15 months of one another.\n",
"BULLET::::- The Commonwealth War Graves Commission maintain and register the war graves... |
i wash my face in the morning, afternoon, and the evening, yet i still get pimples. why is that? | If you are using a powerful oil cutting scrub, you might be washing away too many oils, some that are essential for pore health and regulation. The pores are left open to dirt getting inside them, and the skin overproduces oils to compensate for washing it away all the time. Once a day with a gentle soap would be good,... | [
"More frequent is washing of just the hands, e.g. before and after preparing food and eating, after using the toilet, after handling something dirty, etc. Hand washing is important in reducing the spread of germs. Also common is washing the face, which is done after waking up, or to keep oneself cool during the day... |
how are school authorities not able to control bullying? | First off, it is exaggerated in movies to make a more exciting story, and is not as common as TV or film would have you believe.
Rather than physical abuse being very common, you get harassment and teasing more often. There are many many students and not enough adults to supervise all of them at once, so when student... | [
"Bullying can threaten students' physical and emotional safety at school and can negatively impact their ability to learn. The best way to address bullying is to stop it before it starts. There are many different groups that can intervene to address bullying (and cyberbullying) in schools: parents, teachers, and sc... |
Can Blackholes absorb matter larger than itself? | Any matter that crosses the event horizon becomes part of the black hole. This can cause a black hole to grow to well more than double its initial mass. The enormous black holes at the centers of galaxies did not start out that big.
| [
"There are three reasons the black holes in the ELIRGs could be massive. First, the embryonic black holes might be bigger than thought possible. Second, the Eddington limit was exceeded. When a black hole feeds, gas falls in and heats, emitting light. The pressure of the emitted light forces the gas outward, creati... |
why can’t we just extract greenhouse gases out of the air and utilize them/compress them? | We can indeed. The problem is that it uses a lot of costly technology and some energy, if we want to do a great deal of it.
The slow and cheap solution is called trees. | [
"Removals of greenhouse gases (specifically CO₂) from the atmosphere can be achieved through various forest management options, such as replanting degraded or deforested areas or enrichment planting, but also by letting forest land regenerate naturally. Care must be taken to differentiate between what is a purely e... |
why do people perceive different colours when looking at certain objects. for example the dress from a few years ago that some saw as white and gold, and some saw black and blue? | Your brain makes a lot of assumptions about images you see, this is generally good but can result in disagreements
[Let's look at the checkerboard example](_URL_0_).
Which square is darker? A or B?
Would you believe me if I told you they were exactly the same? Since B is surrounded by even darker squares it ends up ... | [
"By way of concrete illustration Herbart instances “the common observation that the properties of things exist only under external conditions. Bodies, we say, are coloured, but color is nothing without light, and nothing without eyes. They sound, but only in a vibrating medium, and for healthy ears. Colour and tone... |
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