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If Jupiter is heavier than Mercury, then why is it further away from sun?
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That has nothing to do with how far away it is standing. It just formed further away from the sun than mercury did.
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Not a direct answer, but [this video](_URL_0_) I think gives a really good explanation on the effect Jupiter has on the solar system's orbits.
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How was marijuana viewed in colonial America? What were colonial "stoners" like?
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The undeleted comments in this thread and the other two threads cited by /u/caffarelli, as well as my own research, suggest that there is no evidence that people were smoking marijuana in colonial America. While hemp was a popular crop in the Chesapeake, and later Kentucky, it was only used to make rope and bagging. *A History of the Hemp Industry in Kentucky* by James Hopkins has nothing to say about marijuana as a drug until the 1940s. I really think we need to work backwards with this topic; if I might suggest a more fruitful question, "What are the origins of marijuana smoking in America?" Bonus points for a global perspective.
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Minimal to none. Around 1910 it was not illegal, but also barely anyone knew of it especially in Europe. Recreational use would have been more common in Asia and South America. It was simply not very understood, known of or cultivated aside hemp for products such as rope and fabric. Cannabis became more popular towards the 1930s and 40s. From the 1940s you see the earliest "reefer madness" propaganda. Also the propaganda often had racist undertones as Marijuana was associated with Mexicans and they would get portrayed as dirty with the plant. But for uses in ww1 I't was quite unknown in the west. Perhaps some Ottomans smoked it to relax on the frontlines.
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Why does a strobe light, particularly 11-17hz, trigger motion sensors?
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I'm going to speculate that the sensor uses a pulsed infrared LED and a phototransistor to measure presence of hands. Pulsed light is better than steady because you can tell reflected from ambient light. Your strobe is probably matching the pulse frequency of the LED, making the sensor "think" that there's a reflection from a hand.
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It's explained in the info in that video. It's the same effect as [this](_URL_0_). When you use a strobe light at a stream of falling water droplets, you only see the droplets a fraction of the time. If the strobe light is adjusted so that there is a droplet at the exact same space each time the light pulses, it appears as though the droplets are floating. In the video you posted, it is said that no strobe light is used, but with adjusting the frame rate of you camera, the same effect can be achieved.
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How are islands like the ABC islands formed?
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I'm afraid I have to contend the question without solving the heart of it. Aruba, Bonaire, and Curaçao were formed by volcanic activity 80~ million years ago. Though there are sedimentary and limestone deposits on the islands so volcanoes aren't the whole story! _URL_0_ _URL_1_
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The same processes which form islands today, namely [hotspot volcanism](_URL_1_) (e.g. Hawaii) and [arc volcanism related to subduction of oceanic crust](_URL_2_) (e.g. the Aleutian Islands), were active during the time of Pangea. We don't necessarily have evidence of the existence of smaller islands (a lot of the features, especially hotspot volcanism related ones are very ephemeral in a geologic sense), but some of the volcanic arcs that formed at the time were later 'accreted' to continents so we have evidence of their existence. If you look at reconstructions of Pangea and Panthalassa ([e.g. this one](_URL_0_)) you can see some volcanic arcs represented. There likely would have been hotspot island chains as well, but as I indicated before, these mostly would not have been preserved so any added to reconstructions would be total fictions.
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Why do most phone/tablet manufacturers still make use of glass for screens?
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What are the alternatives? Plastic is cheaper but horrible for a phone. The iPhone 6 will have sapphire glass for example.
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Because when glass breaks down into little tiny particles, we just call it sand. Except for some expensive lead crystal glass that has a lot of lead in it, most of the components in glass are pretty non-toxic. Pollution issues with glass are usually less about the glass itself and more about whatever it was made to hold in it, like old CRT monitors and fluorescent lights.
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can the air inside the bubbles of a bubble wrap contain diseases from the area in which it originated?
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Air is not all that good at carrying a disease. So it would be more likely that it would be some kind of liquid (like a sneeze) inside a bubble. However, [the way bubble wrap is made](_URL_0_) is not really conducive to a pathogen's survival. In short, no. Bubble wrap should not be one of your fears.
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They can occlude blood vessels because (if the bubble is large enough) the surface tension of the bubble is too great for the blood to break through it, so it acts like a solid object and stops blood flow. The severity of the damage they can cause is dependent on their size and where in the vasculature they lodge but they can potentially cause heart attacks or cut off the blood supply to your brain. However, bubbles entering the vasculature like in the way you're mentioning via syringe would be unlikely to cause any problem because the bubble of gas is small enough that it can pass through the vessels into the lungs and be dealt with. Wiki has quite a comprehensive and useful discussion about air emboli and the situations in which they are most harmful: _URL_0_
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What exactly happens in your computer when you install a program?
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Two things: - The files needed to run the program are copied to a sensible location on the hard drive - the operating system is told about the program so that it can be easily started in the future. It's the second part that is the tricky one. Do you want it to start automatically every time you log on? Would you rather just have an icon on the desktop? start menu? other command center software? Depending on how you answer those questions, various tasks are performed that make the program easier to run, or create an index entry that the operating system uses to represent the program in a menu. EDIT: formatting.
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There are a few extra pieces of information that your computer stores, called registry entries. Uninstallation removes these, while deleting program files does not. The extraneous registry entries don't take up much space, but they make it harder for your computer to find a useful registry entry among all the junk.
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If a pregnant woman has cancer, is it possible for the cancer to spread to the fetus?
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It’s exceptionally rare. Metastatic disease is usually caused by seeding through the blood supply, or, invasive growth into new organs. Because mums and bubs don’t actually share a blood supply (their supplies run very close together in the placenta, facilitating transfer of nutrients etc, it’s very hard to seed from one to the another, and invasive growth is pretty damn hard through amniotic fluid. There’s a couple of dozen of “proven” cases, mostly leukaemia and melanoma (while melanoma is a solid tumour, it’s insanely invasive), and leukaemia is a liquid tumour which would facilitate the transfer from mum to bubs blood.
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Babies are not made up of ALL their parent's cells. They are only derived from 2 cells, the dad's sperm and the mother's egg. If an egg or sperm is damaged and has a lethal mutation (like being cancerous) it is *highly unlikely* that the embryo will fully develop completely. It will more likely result in a miscarriage. The babies who are born healthy are the ones that did not happen to have any lethal mutations. Now, as a person develops, gains more cells, and are exposed to more mutagens, THEN the person will run into more chances of cells mutating and becoming cancerous.
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Why is suicide attempt considered as a crime?
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[Suicide isn't really considered a crime much in the West](_URL_0_). That said, to the extent it is treated as a crime for anything like secular reasons, it is usually because of ancillary effects. It allows the police to intervene, for example, potentially justifies forcible commitment, voids certain contracts (since contracts to perform an illegal act are illegal), and other side effects of being a crime.
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Simply because they is no law saying you must try and prevent someone from committing suicide.
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How people tuned instruments before we standardized notes?
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When playing an instrument, what really matters is the relationship between notes. That is, it was important, like it is still today, that the difference in frequency between tones was fixed. If you were going to play in an ensemble, one instrument would be chosen and the others tuned according to it.
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It would depend on the person. Some people, like the ones with perfect pitch, would be able to distinguish all of those notes. Others might not. It just depends on how well your ears have been trained in the past. Also there are an infinite amount of notes. If you look on a tuner, it says A=440 Hz. That is the frequency of the note that you are tuning to. On different countries many centuries ago, like England and India and some places in Africa, when they played an "in tune note" their A wouldn't be 440 Hz. Instead it might be 442 or 435. Only in the past couple of centuries has the theory of music, how you write it down and what frequencies the notes are, been unified through most of the world. That's the history of music for ya.
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Considering that a mirror changes the direction of photons, is it actually "deformed" or even "used up" in the process?
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In addition to the point about momentum, real mirrors aren't perfect and absorb some of the light that hits its surface. That absorbed radiation could potentially affect the surface (e.g. oxidizing a silver coating). If you pointed a powerful laser at a mirror it might absorb enough to heat up and thermally degrade or melt. Both of those scenarios don't happen commonly, though.
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A camera has a lens that is focusing the incoming light onto a sensor to register an image. That image is then displayed on the screen, but that is new light - the source of the light is the screen. When you look in a (flat) mirror, there is no focusing work being done by the mirror. It reflects the light at the same angle it came in at, so things get reversed, but your eyes still have to do all of the focusing themselves across the same distance. The "source" of the light is still whatever you're looking at, not the mirror itself.
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How does THC and CBD affect the endocannabinoid system and their receptors? What is anandamide?
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There are two separate cannabinoid receptors in the body: CB1 and CB2. THC acts as an agonist on CB1 that results in disinhibition of dopamine. THC and CBD are both phytocannabinoids, whereas anandamide is an endogenous cannabinoid (it is produced by our bodies) When THC binds to CB1 it activates a G-Protein Coupled receptor which will then activate an enzyme and/or second messenger. The result of these GPCRs lead to a number of effects, such as anti-nausea, calming, and pain-relief. It may help to think of it like a Rube Goldberg device--THC binds to the CB1 receptor, which activates the GPCR, which activates a number of other mechanisms.
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Here's one paper examining CBD: _URL_1_ The Endocannabinoid system is not well understood relative to other pathways in the body. It is known however that CB1 receptors are very prolific in both the CNS and PNS. It is hypothesized that these receptors play a key role. Further reading: _URL_0_
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Why is the rating PG-13 for movies, but T.V. 14 for shows? Why the year difference?
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The group who came up with the TV rating system has *never* provided a reason why they segmented the TV ratings the way they did when the guidelines were created with regards to age. We don't know, and its probably lost at this point.
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It's all about paying for the shows and movies, which movies cost more. TV shows make money on their respective networks when aired because of advertisements etc. and movies are sales oriented.
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Are there any European examples of an emulation of the walls of Constantinople?
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Well, a great many Medieval cities were walled. Many of those walls, (or sections of them) still survive. The walls that were perhaps the most conscious emulation of the walls of Constantinople were those of Caernarfon Castle, in Wales, built starting in 1283, by King Edward I. The bands of colored stone in the walls, and the use of polygonal (rather than round) towers were thought by historian Arnold Taylor to be a conscious use of the imagery of Constantinople, and to also have referenced the legendary dream of Roman Emperor Magnus Maximus, wherein he saw "the fairest fort that man ever saw", within a city, at the mouth of a river, opposite an island, with mountains in the background. This interpretation is not accepted by all historians.
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In 446 AD, Atilla the Hun was busy shaking down city after city in the Roman Empire. The people of Constantinople counted themselves incredibly lucky to be blessed with impenetrable city walls, ensuring their eternal safety. Except that in 447, Constantinople was hit by an earthquake that managed to make *gaping holes* in their precious walls, just was Atilla and his forces happened to be on their way. The horrified citizens arranged a massive, round-the-clock repair effort and managed to rebuild their walls within 60 days, just in time to be ready for Atilla's army. _URL_0_
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How come prisoners in supermax prisons where they're not allowed to talk to anybody don't all go crazy?
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They do. It's a real issue, solitary confinement causes massive mental trauma on those inflicted by it.
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I'm not sure how prevalent it is, but in general the public doesnt really care about the lives of prisoners. Prisons charge prisoners (and their families) ridiculous prices for essential items and completely rob them on telephone charges. What are they gonna do, shop around for a better prison?
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Why is amateur acting (like films made by students for a class presentation or something) so unnatural, awkward, and different from movies/tv shows?
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The quality of acting gets better with experience, and often times the editing and scheduling does as well. An amateur film for a class presentation might have two or three people working on it for a few weeks...and they're splitting their time between filming and the rest of their life. A "real" show has teams of professionals working on different aspects for months at a time.
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Because they're like, um, professional actors and stuff.
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Why is "Z" called "Zee" in America and "Zed" in the rest of the English speaking countries?
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There were two ways to pronounce the letter for a long time. It was apparently a regional way to say it. Thomas Lye in the 1600s wrote a spelling book in England and he pronounced it Zee. (Actually, he wrote "ze" and t is "te" and p is "pe") Here's an interesting quote from the US: 1882 E. A. Freeman in Longman's Mag. I. 94 The name..given to the last letter of the alphabet..in New England is always zee; in the South it is zed. For whatever reason, the zee became the prominent word in the US. You ask why, and despite the many attempts at an answer, *we don't really know.* And that is the unsatisfying but true answer. On the other hand, some Americans definitely WANTED it to be zee, which would make it more in line with the other letters. _URL_0_
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Zed comes more closely from the greek "zeta." Zee more closely resembles how a lot of letters are pronounced (cee bee dee gee pee tee). The split dates at least back to the 1700s in england (alongside zed). Zee came to america and stuck around while it died out for some reason in England. An even bigger mindfuck is the fact that 1 billion is a different number in the two countries by a factor of 1000x
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How do scientists determine the age of the stars, or just their remaining life time?
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In a nutshell: as a star ages and consumes it's fuel it begins burning heavier elements. By examining the signs of these elements being consumed we can use that as one way of measuring the age of a star. Combine that with size and luminosity and that gives an estimate of age and time left before transition to the next phase of it's life. There's more to it but that's the ELI5 version.
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We have one star real close. The sun. We know it's temperature (based on color), it's size (on diameter), it's composition (from spectral diagram), how fast it spins (again, just by looking) and most importantly, age (as very similar to Earth's age (based on Earth geology). We also know mass because it's an easy calculation from size and composition. As you can see, everything except age is learned only by looking at it. This allows looking at others stars, gathering similar information, and comparing it to known. There are also a lot of starts. Sometimes, we can see a star in the process of dying, or being born. And probably, bundle of stars has a similar age just as all of solar system has a similar age. This is how big chart of stars get's created, which we use to estimate age of stars.
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What are the marks on Saturn's moon Enceladus?
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Those seem to be cracks caused by tidal forces, as the gravity of Saturn has the tendency of squishing and then flattening out Encladus depending on where it is in its orbit, for this same reason Europa has cracks like this.
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Some of the photos are false color, and not what they really look like. An actual photo of Saturn doesn't really look fake though.
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What is the pH of our drinking water?
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Depends on where you are. Typically some ions are mixed into drinking water so that it doesn't leach from pipes or your bones. For example, SF area is pretty good at keeping drinking water at about 6.8, but water near Reno is not uncommon to reach like 8.6. Some places even have pH that varies based on things like weather and population density.
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First of all- you will be hard pressed to find a sample of water that is a perfect pH 7. ANY impurities will throw it off. The acidity of water will depend on where you live. Even distilled water is rarely a perfect pH 7 due to dissolved CO2 and other gases. There are, however, solutions that are a perfect pH 7 and will even resist changes to pH. [They are called buffer solutions.](_URL_0_) I won't get into how they are made, but they do exist and normally they consist of a salt dissolved in a weak acidic/basic solution. They don't usually have any really special properties other than maintaining their pH despite changes in the environment. They are mainly used for calibration of pH meters and such.
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Solar Cell Electricity, where does it go when the battery is full.
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Doesn't go anywhere. Once the battery is charged the charge controller will (essentially) break the circuit. With no path to follow (electricity flows...) there is no flow. No flow means no transfer of electrons. The panel cells still have potential energy but it does not move. Caution: my knowledge of this is very very old and I no longer study in the field.
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The entire station uses DC power, generated by the numerous solar panels protruding from the station. Since the earth's atmosphere reflects a large amount of the sun's light, the solar panels are double sided, effectively doubling the power generated. Since just under half of the station's orbit is sunless (ie, when the earth eclipses the sun) there are large Nickel-Hydrogen batteries that charge when the station is exposed to the sun, and are depleted when it has no sunlight. According to NASA the panels cover an area of about an acre, and can generate between 75-90 Kilowatts of power.
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What happens in your body when you can taste food that you are thinking about?
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Everything you experience is only being experienced because your brain exists. You can have a tongue that's alive, functioning and even "tasting some food" but if it's not attached to the brain. It isn't experiencing anything, it isn't perceiving anything. It's your brain that does all that. So when you think about for e.g steak your brain is simulating the reactions that the tongue produces when it "tastes steak" So you're basically tricking yourself into thinking it's there. TL;DR/notelim5enoughELIM5: your brain can trick itself into thinking something is there because it remembers what the tongue told it when it tasted that thing it tasted
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Acquired taste. What is acquired taste? Things that taste good to you are things that your body is familiar with- Things you have eaten since you were a child and things that have similar traits to things you ate as a child are what you mostly like. Pastas, breads, cheeses, and meats are very common starting points for many people. Things that taste bad to you are things that have a very foreign taste to your taste buds. They are something your body doesn't know anything about. This rejection is a survival mechanism that would help prevent hungry people from eating things they shouldn't eat in the wild. This is also where the urge to chuck up really bad tasting food comes from. The cool part is that you can train yourself to like literally any food(has to be edible, you can't train yourself to like concrete) that you currently don't like by eating it enough. Once your body decides that the foreign thing is not harmful it will gradually quit rejecting it as bad tasting.
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How do our cells differentiate between the sense and antisense strands of DNA to make sure they make the correct mRNA and protein?
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The TATA box is just one part of the promoter sequence. There is also a more complex sequence near the TATA box, which is often used as an identifier so particular genes can be trascribed only under specific situations (such as in particular cells, or at a particular stage of development). These sequence would not be the same in the sense and antisense portion of the DNA, thus preventing the transcription of the antisense portion.
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different areas of the dna are modified in different cells so they are more or less accessible to the enzymes which transcribe it into rna. different patterns of accessibility = different type of cell. epigenetics yallllllll.
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What is political science and why is it considered a science?
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Political Science is the study of human interactions in political spheres. You might liken it to cultural anthropology, psychology, sociology, or another "human centered" field of study. It's a "soft science" meaning it's not like biology or chemistry where you'll form a hypothesis, test it experimentally, and then adjust a theory from the experiments. It's an observational science where people form theories of human behavior and try to quantify or qualify them through real-world case studies and examples. You're dealing with how people perceive and act in events mostly.
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It's considered a social science, like political science, sociology, psychology but not a natural science like chemistry or physics. Social sciences don't have hard and fast rules that are replicable, because you can't isolate experiments in the real world like you can in science labs.
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How do cameras or displays determine between 120 fps being slow motion or just really smooth game play?
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The recording and playback speeds are not necessarily the same. If you record at 120 fps and playback at 120 fps, it will look normal, but if you playback at 60 fps instead it will look like everything has been slowed down to half speed.
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There's relatively little data being passed around for the game, it's not like streaming a 1080p 60fps video. The computers are just exchanging information about who has moved, fired their gun, etc, and all the rendering of the images happens on your computer based on that information.
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When did the Gothic people of Sweden start assimilating to Swedish culture, and when did they stop identifying as Goths?
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Are you talking about the Geats (Götar) rather than Goths? Or perhaps Gutnish (Gotlander) people?
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[I answered a similar question here a few days ago, this one is only for Sweden though](_URL_0_).
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It's been said that a photon travelling at the speed of light basically travels almost instantly from it's point of view. If true other than WTF does this mean a photon can navigate the universe almost instantaneously? and WHY
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Neil deGrasse Tyson (noted and famous astrophysicist) answered this in his [first AMA](_URL_0_) on Reddit (top question in that link if sorted by "top"). I'll quote it here: > Since time slows relative to the speed of light, does this mean that photons are essentially not moving through time at all? Response from Tyson: > yes. Precisely. Which means ----- are you seated? > Photons have no ticking time at all, which means, as far as they are concerned, they are absorbed the instant they are emitted, even if the distance traveled is across the universe itself.
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In the photon's frame of reference, they have no travel time. In our frame of reference, they do. In their reference, they are travelling at such a high speed, the distance they travel shrinks to zero and they arrive at the time they left. In our frame of reference, they are just travelling fast and time/space isn't shrunk. Does that make sense? edit- source: i'm a physics major Edit 2- as people have pointed out, a photon doesn't quite have a frame of reference. However, if we consider particles as they approach the speed of light, the logic holds.
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If all different types of waves on the electromagnetic spectrum are just higher frequencies, why can't we make a 'box' to produce all of them?
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How do you wave it fast enough - without an input that has the right frequency already? Producing gamma rays by hitting electrons with gamma rays (to make them oscillate rapidly) is possible, but we usually call this "scattering". For lower frequencies we can use electronics to drive electric currents in antennas back and forth - this is how radio waves are produced, for example. You can adjust the frequency of them as well.
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Well.. you can always try running towards the antenna is extremely high speeds. That should blueshift the emitted waves. Otherwise, I'm afraid antennas stop behaving according to conventional antenna theory by the time you reach IR or terahertz frequencies. You cannot produce a conventional oscillator that drives a large antenna at those frequencies. You could always just try to boil the antenna and claim that the black body radiation it is emitting is the output but that seems like cheating. You could also build a particle accelerator to swing around electrons at high speeds and consider their synchrotron radiation as your antenna output, but that seems like cheating in the other direction. All in all, the physics of the real materials used to build an antenna tends to get in the way of you being able to do that. Of course an "ideal" antenna with an "ideal" AC voltage source and "ideal" wires can do whatever you can dream up.
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Why was volley fire prefered with muskets and arrows vs. allowing everyone to fire at will?
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There is misinformation in this thread in that in volley fire all men in a 'unit' would fire at once. Volley fire would prevent exactly the problem of everyone reloading at once. If it takes 2 minutes to reload a weapon, and the range of your weapon can be covered on foot or by horse in that time, as more heavily armed troops will stay at a distance until everyone has fired. If some people haven't fired, they can make it very bad for people to come into closer range
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They used firing line to maximize firepower. Back then they used muskets which took about a minute to reload so by setting up three lines they could fire every twenty seconds.
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Do bees have spatial memory when foraging for food?
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It [seems](_URL_0_) as if they base their navigation off what they would consider novel landmarks. While this can be a form of spatial navigation/memory, it is probably integrated with the direction of the sun/olfactory systems.
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> Do they forget as soon as they dodge our hands what just happened? Insects can be conditioned to avoid something that they find attractive. _URL_0_ But conditioning takes more than one instance of danger in a location where there is something attractive (such as food). So the insect will try again until it either gets the message, or is killed.
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Fog with temperatures below zero (°C) , how can it be ?
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Fog can happen as long as the air is saturated, and saturation means when the air can’t contain any more water vapor. The colder it is, the less water vapor there can be in the air. Still, below freezing, there can still be saturation.
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Fog and mist exists *because* cold air can't hold much moisture. I think what's confusing you is the usage of the word "hold". In this context, fog and mist is not regarded as "held" in the air, fog and mist are tiny droplets of water in the air. Water that is "held" by the air is water vapour, water in a gaseous state. When the air is saturated with water vapour, any excess water is going to condensate into tiny droplets - fog or mist. If a warmer body of air, that is close to being saturated with water vapour, allows to cool down, it's going to be supersaturated, and water will condense into fog or mist.
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What is a black hole's ergosphere?
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Big objects 'drag' spacetime around with them. A spinning black hole will have an area of spacetime around it that spins aswell, because of this, dragging spacetime in a circle around it. The ergosphere is the area around the black hole where spacetime is being dragged at a speed greater than the speed of light. It's called the ergosphere because you can extract work from it because of this. An object that falls into the ergosphere *must* start moving around the black hole, because otherwise that would require it moving at a speed greater than the speed of light *against* the rotation of the black hole. This apparent force on the incoming mass comes from the black hole's energy, and theoretically you can use this process to extract energy from a black hole.
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I'm assuming you're referring to the shape of its event horizon, which is an oblate ellipsoid.
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Is it possible to invent an engine with the same efficiency as the Carnot cycle?
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The short answer is no. The Carnot efficiency is, as you said, the maximum efficiency that a heat engine can have. It assumes that things like friction, wear on moving parts, vibrations/sounds induced in the engine, etc do not exist. These things will always be present. Friction is certainly not going anywhere, since an engine is generally going to be moving/turning something. The Carnot efficiency is a limitation placed on us by the laws of thermodynamics, it tells us how good our engine could be if we made it out of frictionless, infinitely strong, infinitely stiff material.
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In theory, yes, it would be possible. However, the second engine will take more energy to run than it will produce, and harvesting gases from the first engine will also lower the output of the engine, so the second engine will be nothing more than a huge parasite for the gasoline engine.
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How can babies sleep in awkward and uncomfortable positions, without showing any symptoms of pain, such as a stiff neck or back that adults would normally show?
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They're limbs and muscle are aren't fully developed. Babies are made of mostly cartridge (like the stuff you find you're ears and nose are made of) so they are more flexible
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We all wake up during the night. That is normal during certain sleep stages. Unlike infants, we have learned to go back to sleep. These waking moments are usually short and we forget about them afterwards, or we actually be awake and go to the toilet, etc. The 'half-awake' state can cause sleepwalking. You'll be fully awake, but not fully conscious. The opposite happens as well: you're fully conscious, but your body is still asleep. That is when we experience sleep paralysis. For infants this is new. Everything new can be scary, because they lack the experience to deal with it. I once had to calm a crying child who was thirsty, but actually half asleep. I had to keep him standing up to drink, then 'walk' him back to his bed to continue his sleep. Small humans are weird.
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Can someone tell me why burning Mercury Thiocyanide causes it to grow 10x it's initial form?
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Mercury thiocyanate undergoes decomposition at around 165 degrees so when it's set on fire, the substance produces Sulfur dioxide and mercuric vapor. The decomposition of mercuric thiocyanate is an intumescent reaction, which means when you add heat to an intumescent compound, the volume expands (and density of course decreases). As to why that occurs I can't say for sure, but from what I've read I would guess it's because the vaporizing mercury and formation of sulfur dioxide creates air bubbles within the substance as it is decomposing.
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So there are two reactions occurring here: The first thing you see is the decomposition of the ammonium dichromate: (NH4)2Cr2O7 → Cr2O3 + N2 + 4 H2O This is known in pyrotechnic circles as "Vesuvius Fire," where the heat from the combustion causes the chromates to give off the slow red burn you see in the beginning. The second reaction is the decomposition of mercury(II) thiocyanate: 2Hg(SCN)2 → 2HgS + CS2 + C3N4 Where C3N4 is the compound that makes up the "snakes," and grow due to the evolution of gases produced by the decomposition of the other products: CS2 + 3O2 → CO2 + 2SO2 2C3N4 → 3(CN)2 + N2 HgS + O2 → Hg + SO2 This is also known as the "Pharaoh's Serpent" in pyrotechnics. Both mercury and cyanogen gas are very toxic, so please don't try this at home.
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Why don’t we cook things at higher temperatures for less amount of time?
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I'm going to assume you mean in an oven and not a microwave. Think of it this way - when you lay out on the sun what warms first? Your skin. The same is true for cooking in an oven. It takes time for the heat to work its way into the food as it needs to warm on the outside before the inside will get warm. If it was too hot, the outside would crisp and burn before the insides were properly warmed. My favorite example is when cooking a pot-pie. I can never get the outer ring of crust to avoid getting really crisp unless I cook it at the lower temp for longer.
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In general everything has a rate of heat absorbtion and dissipation, things that get hit faster also cool faster and things that take longer to heat are slower to release the energy. This will mostly be a combination of the materials density and makeup, but for foods the easiest observation would be water density. Water absorbs heat and dissipates it rapidly so the more fluid inside the food the faster it will heat and cool compared to foodstuffs with less water.
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Why do musicians use their non-dominant hand on the fingerboards of string instruments like guitar and violin?
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Guitarist here. You're right, it seem weird. But, try fretting with your right hand. Easy, right? Now try plucking a few strings with your left. Easy? Hell no. It's easier to learn fretting with your non-dominant hand, because your dominant hand already has the fine motor skills required to pick. Therefore, your other hand can learn independently.
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Because a hand without a body running around on its own called thing generally is.
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Why is Free Bird so famous?
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I assume you're asking because of the old joke of yelling "FREEBIRD!" at non-Skynyrd concerts. The song itself is not the issue, it just happened to be a well-regarded song around the time that people started making the joke and sharing it and repeating it. Sort of like how on Reddit, there's a joke about the movie "Rampart" originating from when Woody Harrelson came to do an AMA but only wanted to answer questions about that movie — if he'd been promoting a different movie at the time we might be making a joke on _that_. People who shout "Freebird" don't actually want or intend to hear "Freebird" (we assume) — they just want to be the person who makes the joke, and gets the laughs/groans/recognition, or, to extend our Reddit analogy, upvotes and karma. Some further thoughts: _URL_0_
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Because everyone suddenly wants to sell wings but the bird only comes with two. Supply and demand.
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why do collegiate athletes from military schools (Army, Navy, Air Force) need permission to play in pro sports?
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When a person is accepted into a service academy, they don't pay any tuition but they make a commitment to serve a certain term of years in their chosen military branch after graduation. If that player is drafted by a pro franchise, they can ask the military to defer or waive their service requirement which in this case the Navy agreed to do.
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The NCAA wants to differentiate itself from the NBA to minimize the perception that the players in one billion dollar league are very well compensated while the players in the other are lucky to get a scholarship.
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Why can't a computer program, program itself?
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Here's one reason (among many). Human languages are very imprecise. If you tell a computer program what sort of program you want just by speaking to it in your natural language, it could only have a very vague idea of what you want. It's hard enough to tell a human what program you want. You'd need a very advanced AI to do this. It would have to know a lot about the world to be able to "fill in the blanks" and figure out what you really want. Just like a human has to do. There are experimental programs that do this kind of thing, but only in a really basic way. To make a computer program which could make any other computer program based on someone just speaking to it naturally would require an AI approaching the intelligence of a real human. And if you do that, what's to stop it taking over the world and destroying humanity? Ok, that last sentence was a joke. Or was it?
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Code is executed as binary machine instructions in memory. Ever since we stopped programming computers with wires, there has been a way to make a file, or a tape, or a ROM, or load core (Google "core memory"). Some ways were bad, manually transforming instructions to binary, or octal, or hex, and then punching them on a tape. The good ways involved taking text, originally one line per paper card, and feeding that text into a program that would give you the resulting binary. Then you put the binary on a boot store and start up the computer. This is still the way embedded computers are programmed, when it's important that they not make mistakes, bare machine programs without an OS.
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Why is it that uploading is always so much slower than downloading?
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Upload speeds aren't necessarily slower than download speeds, they're just intentionally slower for your average home internet connection because you don't need huge upload speeds. If you're watching a movie on Netflix, you just have to send a few dozen kilobytes telling them what movie you want to watch and then you'll receive several gigabytes of data, so you're receiving thousands or millions times more data than you're sending. So say the average home user's connection can handle 20Mbps in total, having a symmetrical connection with 10/10 up/down means that most of the upload speed is going to waste most of the time, because they barely upload anything, but it means their download speeds are slower so it takes longer to download the latest movie/game/whatever. With speeds something like 2/18 up/down, the average user notices next to no difference other than their downloads taking half the time.
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If an ISP can provide you with X amount of bandwidth, they then have to decide how much of it is divided into download and upload. To make your upload bandwidth higher, they would have to reduce your download bandwidth. The average user will value a higher download speed more, so that's generally what they provide. You can find ISPs that offer better upload to those who want it though.
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How can half of American workers make less than $30,000 a year, but the median household income is $51,000 a year?
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Therein lies the issue with averages. Most households with only one income have a single high earning income, driving up the average. Households with two earners tend to both have lower incomes. That said, in the US: 13% of households have 1 male earner w/kids. 31% have 2 earners with kids. 25% have 2 earners with no kids. The remaining 31% are non traditional households, where only the mother works or at least on of the members is retired. So 85% of households may be a little high, but 2 income households are definitely in the majority.
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Just because the median went down doesn't mean the total income went down. Median is the number in the middle, but it doesn't show you what the top and bottom numbers are. {2, 5, 8} - Median, 5 {1, 5, 10} - Median, 5 {4, 5, 500} - Median, 5 Total personal income in 2000 - $8,554,866,000,000 Total personal income in 2000, in 2012 dollars - $11,406,190,000,000 Population in 2000 - 282 million Personal income per capita, in 2000 dollars - $30,336 Personal income per capita, in 2012 dollars - $40,447 Total personal income in 2012 - $13,401,868,693,000 Population in 2012 - 317 million Personal income per capita, in 2012 dollars - $42277 So even adjusted for inflation, personal income per capita is higher now than it was in 2000.
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Why are wheels on carts, office chairs and some other moveable stuff off center?
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Being off center of the mounting pin forces the wheel to trail behind the direction of movement. That allows them to always be aimed in the direction of travel.
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A spinning object will always resist a torque that tries to change the direction in which it is spinning. This is a product of the conservation of angular momentum. Google 'gyroscopic effect' and you will see many examples of bycicle wheels being used in weird balancing tricks. In plainer terms: If a bike wheel is spinning perpendicular to the road surface, its gyroscopic 'force' is oriented vertically. It will tend to resist any change to this orientation, which makes it easier to keep your balance. A stationary wheel has no such forces acting on it, so it will more easily fall over.
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If the sun emits heat into our solar system like a giant space heater then why is the universe so cold if it has trillions of stars like the sun?
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The nearest star to the Sun is a few light years away. We're about 100 million miles away from the Sun, about a millionth of the distance to the nearest star, and even here the Sun barely warms space. The Earth is warm because it has an atmosphere to trap the Sun's heat, but leave the atmosphere and you'll freeze your buns off. And that's a millionth of the distance to the next star over!
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The Sun is a huge ball of mostly hydrogen. It's so big that the centre is under enormous pressure, so enormous that it squeezes the hydrogen atoms together to form helium. This process releases a huge amount of energy. That's where the heat and light comes from - it's not burning like a fire. To get an idea of the size of the sun: it converts 600 million tons of hydrogen into helium _every second_. Even at that rate, there is still enough to material for the sun to keep fusing for another 5 billion years.
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Is there any genetic or biological reason some people prefer salty tastes to sweet, and vice versa?
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In mice, we know for sure that there are genetic variants that influence the ability to taste and overall sensitivity to sweet, bitter, and salty compounds in the taste bud. This work led to the discovery of sweet and bitter taste receptors. There is some evidence that variants in these receptors are correlated with response to tastants in humans (you can find review articles, but [this](_URL_0_) will give you an idea of the logic of these kinds of studies). Edit: Here's a good overview of the topic _URL_1_
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Here's a nifty history on salt : _URL_0_ So basically, we should distinguish taste from flavor. Taste is usually defined as the intensity of a sensory reaction to a food on the anatomical tongue. Flavor is one of the five: sweet, salty, ugami, bitter, or spicy. Taste is almost always used the same way flavor is used so its not a huge deal but something to consider! When salt touches the tongue it triggers the salty parts but when salt and sweet comes together the taste buds are anatomically compatible. Evolutionarily speaking, sweetness is usually associated with foods that we should eat in nature (fruit, meat, starch). But salt tastes pretty gross alone and we need salt. So by pairing salt with sweet it is more pallable!
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Industrial Development and Efficiency in the USSR
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Much of soviet growth was illusory and shallow. My favorite example [is shoes](_URL_0_). the USSR produced more shoes per capita than any society in history, but there were still massive lines to buy imported shoes whenever they were available. Why? because the domestic shoes were so lousy and uncomfortable that no one really wanted them. So there was a whole industry, whose production was included in GDP figures, that was producing goods that no one wanted. all of soviet industry was shot through with problems like this. they could make a lot of relatively simply stuff, like steel, but anything that needed any sort of serious quality control had problems. Soviet weapon designers would have to order twice as many vacuum tubes as they needed for some electronic equipment because they knew that half of them would be defective out of the box.
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I'm sorry but I don't fully understand the question. Misread how? In the sense of the robustness of the Soviet economy? My understanding is that the CIA and others grossly overestimated the size of the USSR economically. In the sense of the foreign policy goals? In their technological advancement? Can you elaborate, please?
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Why does the exact same post appear as the 4th post on the first page and the 27th post on the second page and the 53 post on the 3rd page?
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> there's really no such thing as "pages" on Reddit. Instead, you're saying "give me the links (from my current 50 subreddits at this time) #1 to #[page size] as ranked by voting right now at this exact moment"... When you go to the next page, you're saying "give me links #[page size] to #[page size2] *at this exact moment"... This is why you may see duplicate links from page to page! A link that was #23 a minute ago may be #26 now because of people voting things up and down
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"Basically, it looks for the largest image on the page that is somewhat squareish (it has to be less than 1.5:1). If two or more images are tied for largest, then it does the one that is found last in the html." Jeremy Edberg [source](_URL_0_)
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When did militaries start using spears, and why did the use of these weapons sticked out for so long, so widely ?
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The spear was probably the earliest weapon used by "armies." There were probably tribal bands with clubs and stones before that, but keep in mind spears were ancient hunting implements. They had a long life for a number of reasons. They were easier to make than swords as they were just a pole with a pointy end. They were cheaper than swords and used less metal for the same reason. They allowed troops to stand back and offered some protection due to that. They were well suited to the rank-and-file style popular in the ancient world. They were simple weapons that could be used by ignorant peasant levies with minimal training, whereas swords required specialized training.
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> I guess they'd be good for riot control, but wouldn't a sword be better for fighting in close quarters? Spears are great for crowd control, because they keep the crowd far away. However you are correct in saying that a short sword or a long dagger would be much better in the tight side streets of Meereen. Maybe they never expect to actually have to use their weapons and were carrying them for psychological effect. > Did any civilisations use spears? What are the more common patrol weapons in medieval Europe? Spears (or other long and pointy weapons) were pretty much the standard for almost every soldier or mercenary in all of history.
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Why do we say "dehydrated" instead of "Malhydrated". And "malnourished" instead of "denourished"?
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Dehydration is the lack of hydration, whereas malnourishment doesn't mean you're not getting nourishment, just bad nourishment. One is the absence, the other is just low quality.
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Being dehydrated doesn't stop your body from producing garbage that needs to get out.
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Why is laundry lint almost always greyish blue?
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All of the individual colors of the clothes that are in there mix up and make a darkish mess, just like if you mixed a bunch of paint colors together. Sometimes if something is shedding a lot of fibers, like a towel, or if you have a lot of similarly colored clothes, then that can influence the color of the lint.
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The colour results, as a study from 2001 suggests, from the mixing of all fabrics you wore as clothes into an average new colour, which is then a light grey/blue. The lint is created upwards, more from your underwear than from your shirt though. This is caused by more friction through hair in that region. However, there is some controversy on the colour. The Guinnes World Records Holder, Graham Barker for instance declared that his lint is more of a redish colour, even thouh he wouldn't wear much red apparel. The study can be found here (German): _URL_0_ The guy who made said study got a (Ig) Nobel prize for it: Karl Kruszelnicki Edit: It's actually a Ig Nobel prize. A parody of the Nobel prize. thanks to user /u/throwaway3_14159265 Edit: price/prize
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Could someone explain to me like I'm 5 how the US education system works?
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You have preschool, kindergarten, then elementary school (grade 1-5 or 6), middle school (grade 5 or 6-8), and then high school. In high school, you are there for your 9-12th grade. By your 11th grade, you are expected to take either the SAT or ACT; depending on what college you're trying to get into. Universities then look at your scores on the ACT/SAT and your high school grade and chooses you depending on what the requirements are for each. Most universities also require an essay; basically accomplishments on what noteworthy things you have done so far and why you chose the school. Scholarships are awarded for everything. Sports, high grades, high SAT scores, etc.
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Where I went to college you get credits for passing classes. You need a certain number to graduate. After you pick a major or minor you need to complete certain required courses for the major and then a certain number of credits in whatever classes you want within the discipline. So for example for my CS degree I had to do classes like C programming, discrete math, scientific computation, digital logic, etc, and then a certain number of credits in any CS related classes I wanted (AI, compilers, computer architecture, etc). I also had to do a bunch of math classes (since I was in an engineering school) and certain liberal arts classes that everyone had to do.
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Do we have any indication of what early peasant music sounded like?
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Could you provide some examples of the recordings you heard, and narrow your question to a specific time period and place?
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I will leave it to social historians of the 1950s and 1960s to provide a social/cultural context for why this caught fire. At the same time, it is important to point out an important underpinning namely, the work of [John Avery Lomax (1867-1948)](_URL_1_) and of his son, [Alan Lomax (1915–2002)](_URL_2_) both of whom contributed a great deal by way of collection hundreds if not thousands of folksongs. They followed in the European tradition of folksong collecting, virtually creating the field in the US. While many singers adopted the folk sound while writing their own material, the urban appetite for (and much of their material) grew out of the work Lomax, father and son, who not only collected, but made many of their discoveries popular. The sources are from the dreaded wiki, but the articles are good and provide an adequate overview. See also the [Library of Congress article](_URL_0_).
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How do hurricanes weaken over land? Where does all that energy go?
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Hurricanes require warm, moist air found right above the surface of warm waters (places near the equator) to sustain the wind speeds and clouds found in a hurricane. Over land, they no longer have these conditions, so the clouds and air slowly diffuse away into the surrounding areas, which makes the hurricane weaker and smaller, until it becomes a patch of clouds and rain.
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During the summer the ocean warms up. This heat gets released as water vapor into the air. The water will cool and condense and fall as rain but the heat stays in the atmosphere. If enough heat collects in one place it will create an area of low pressure. This low pressure zone causes air to rush in from the surrounding areas of higher pressure. But, the air doesn't come straight in, it spirals into the center. This is why hurricanes rotate. As they are fed by more and more water vapor from the warm ocean they will get bigger and more powerful. The prevailing air currents will eventually push the storm onto land somewhere. In the Atlantic this tends to be the east coast of the US and Gulf of Mexico.
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Why haven't we made a hoverboard yet ? What is limiting it ?
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We don't possess legitimate antigrav technology, nor any knowledge of how to begin to create it. A hoverboard would instead have to rely on air pressure like a hovercraft, which would be both difficult to keep stable in a skateboard-like object, but also hard to generate without some fairly significant blowers affixed.
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We have [Maglev](_URL_0_) trains, which is a stepping point to what you're asking about. As for actual hovercars, not with our current technology and understanding of physics, but, as Michio Kaku would say, this is a class 2 impossibility. That is, to say, it's not outside of the realm of physics, and doesn't violate any of the laws we currently understand, but for now, it's well outside of our engineering knowledge.
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After Dec 21, do the days start getting longer immediately, or are there a few days that are more-or-less equal?
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Depends on your [latitude](_URL_0_). Day-to-day difference in the day length will be greater when you are further from the equator while length of the day will be very similar closer to the equator. As you can see from the curves, this change is a continuous process.
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Yes, you are 100% correct. They will have the same date. The only constant is that they will be 23 hours apart. Which means that on one side of the date line there will be people who are completely done with that day and on the other are people who are just beginning that day, but they will for 60 minutes share the same day.
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Why can we see dim objects better by looking next to them instead of at them?
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Our eyes contain photoreceptors which convert the light hitting our retinas to the electrical impulses our brains actually receive and create images from. There are two sorts of these photoreceptors; rods and cones. Rods are more sensitive and thus can pick up lower light levels, and cones are better at receiving colour and detail, but aren't as effective in low light conditions. These cones are more numerous in the centre of our eyes, where they're the most useful. A consequence of this is that when we look at dim objects in low-light environments, our rods 'perceive' them better. The rods are more numerous away from the centre of the eye, so by averting our gaze slightly we can use them to see dimmer objects better. More here: _URL_1_ And here: _URL_0_
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Your eyes contain 2 kinds of receptors rods and cones. The cones are more prevelant in the center of your visual field. They let you see in color, but are less sensitive in dim light. The rods only let you see in black and white but are more sensitive so, under certain conditions of dim lighting, you can actually see something a little better by not looking directly at it.
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Why do we need to boil pasta? Why isn't it enough to soak it in water?
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You need the heat from the boiling to cook the starch/flour which is an ingredient of the pasta. Try this at home. Take some flour and mix it with cold water. do the same with boiling water. you'll notice the difference. only by cooking the pasta gets soft but still sticks together.
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Pasta is composed largely of wheat flour, which contains a lot of starch. Starch is really just a kind of carbohydrate, and is made by plants during photosynthesis and functions as an energy store for them - plants can degrade starch later using a whole bunch of enzymes and cofactors to produce energy when they cannot do photosynthesis (like when there is no sunlight). For humans to be able to digest starch, we have to cook it. This is actually an actual biochemical process called *starch gelatinisation*, and in this process, starch and water are combined and heated and the granules of starch swell up and increase in volume. This is pretty apparent when you are making pasta, because a little bit of dried pasta can become a large quantity of cooked pasta. They also develop a chewy texture, which is where the term "gelatinisation" comes from. It's also noteworthy that this is an irreversible process under standard conditions, meaning you cannot go from cooked pasta back to dried pasta.
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does male baldness really derive from his mother's father or are there other factors involved? Is there any way to slow or stop the balding process?
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Being [castrated](_URL_0_) before losing your hair stops male pattern baldness.
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Women can go bald, but male pattern baldness, specifically is a recessive trait on the X chromosome, meaning that it will only be expressed if you dont have a dominant version of that trait. Women have two chances to receive the dominant version (they're XX), but men only have one chance (they're XY), making it more common in men
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What's the order of magnitude of the resistivity of a superconductor?
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[Here's](_URL_2_) a paper I've seen cited which found currents with so little decay that they put a lower bound of 10000 years or so on its decay rate - and that was in 1963. That is, I(t)=I_0Exp[-t/T] where T is at least 10000 years. [Tinkham's textbook on superconductivity](_URL_1_) argues that decays can only occur on times greater than 10^10^10 years (the latter number describes a transient decay in type-II superconductors that will go away upon reaching a low enough current). So yes, unless you do something to stop it from superconducting ([or add exotic effects](_URL_0_)), superconductors have zero resistance.
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Superconductors have a "critical current" beyond which the superconductivity is broken, and you no longer have a superconductor, just a normal conductor.
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How does forearm armor account for the fact that a wrist can rotate ~90° with respect to the elbow?
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It is basically a metal plate upon a leather brace - where exactly do you see the problem? Rotating a stiff metal plate on your arm? Take a roll of tape and a few sticks and secure them near elbow and wrist - they will rotate with your wrist/arm movement just fine, like a metal plate secured with leather straps would. If anything else is bothering you - what exactly is it?
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I would think it would depend on if your forearm developed the extra musculature to use the extra finger in the same way as the rest.
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Where dies the "Captain goes down with the ship" thing come from?
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This answer will violate subs rules, but my response is based on years of studying naval tactics, battles, etc. A ship captain was in total command of his ship, he was responsible for literally everything, the crew, the ship, the provisions, the training, the sailing, the navigation. Everything. So, if something went wrong, whether or not he had any control over the event (thinking storms here), he was responsible and would be held accountable. A captain who 'lost' a ship was branded and probably would never command again. A good example of this was the British naval tradition of court martialing any captain who lost his ship under any circumstances. His ship my have been attacked by a vastly superior force, he fought to the very last round of ammo, his ship sunk underneath him, but he would still be held responsible for the loss until proven otherwise. The stigma of loss was so strong that the only way a captain could retain his honour was to die with his ship.
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You know in the movie Captain Phillips where the Pirates storm the ship, point guns at Tom Hanks, and say "Look at me. I am de captain now." It's like that, except the Pirates are the army, the ship is the government, and Tom Hanks is the king/president/whatever
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Did neckties or bowties serve a practical purpose, or have they always been decorative?
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I always thought that neckties were worn to keep your collar from flapping open and making your neck/chest cold.
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(_URL_0_) Neckwear has existed in various forms since antiquity but the modern tie (and other mother neckwear such as cravats) started as a fashion statement popularized by King Louis XIV. It gradually evolved into the longer tie which has become customary in the west as it is easier to tie. In some form, the tie was likely a status symbol (saying "look at me, I can afford to drape rich silk around my neck with no practical use") but gradually became accepted as formal and then business attire, hence our modern usage.
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What's the diffrence between a rebellion, and a revolution?
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Mostly who wins. If a group of people rise up and overthrow their government, they will typically term their uprising a revolution (see: American Revolution, French Revolution, Russian Revolution). If they rise up and are unable to overcome the government, they are typically termed rebels. It's worth noting that pretty much every revolution starts as a rebellion, and only becomes a revolution upon victory.
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Political linguistics. Portraying the war as a 'revolutionary' effort painted the rebels in a heroic light: they were overthrowing the imperialist establishment. This also appealed to a number of people living in Britain, mind; it became lucrative for businesses to sell accessories that referred to the 'revolutionary' cause. (Anything to bash the government with.) However, journalists and government documentation at the time using 'war of independence' at least suggested an alternative to the demonisation of the British regime. If the Americans were deemed to have little to 'revolt' against, which the term 'revolutionary' refers to, a different description suggested their motivation was wanting to become an independent state more than making a stand. (I will say that, as a Brit myself, it usually *is* referred to as the American revolution here, at least colloquially. If anything, 'war of independence' is more an academic term in modernity.)
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Why it takes up to 10 business days to unsubscribe from marketing emails.
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Markting emails are generally queued in the system. So that email you receive today was actually written a week ago and prepared to be send out today at XX:XX time. So, when you unsubscribe today, there are still several emails already queued up to you in the system. Removing you from those queued emails is more effort than they want to bother with, especially as they won't be getting anything out of it. So, they just update their email file for new emails, but leave you in the queue for old ones, which is why you might end up still receiving emails for a few days.
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they send the mail not instantly, they hold it back for a moment. if you decide not to send the mail it had never left your mailbox.
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What were the long-term effects of Queen Elsa's ice entitlement in Arendelle?
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Look, I see where you are going with this, but please stop. Queen Elsa was in a difficult position and did what had to be done for the survival and future of Arendelle. The ice market was clearly already in steady decline because... well... ice. No other outcome was possible. **TLDR; Lay off Elsa.**
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If all of Greenland's ice sheets melted, it would cause a rise in Sea level of approximately 6 to 7 meters. However, at the present rates of melting, this would take around 14,000 years. That is not to say that it's acceptable for it to melt, just that the scale is a longer period of time. Antarctica's complete melt would cause a rise of about 61 to 62 meters, but would take a vastly longer amount of time. As for other effects, such as ocean desalination or changes in the regional albedo & thus global insolation, I don't have exact figures. One year on its own, at the current rate, is generally not enough to cause a noticable difference, but cumulatively, in as short as a few decades, it will add up.
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Why haven't we been able to analyze samples of different foods to find out exactly what the ingredients are and the percent of each ingredient in the food? You know, to unlock the mysteries of Coca-Cola, Big Mac sauce, etc.
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We can do this. We can tell you exactly what chemicals are in any particular food. The problem is, if you're attempting to replicate a "secret recipe" is that most of these chemicals will be complicated organic molecules, so we can't exactly reconstruct from scratch by adding chemicals to a vat because it'd be prohibitively time consuming and expensive. Knowing what's in something doesn't tell us the method of creation.
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There are tons of analytical methods for determining composition of analytes. Separation based on physical or chemical properties of a sample will vary depending on what you're looking at. For example, if you wanted to know how much of olive oil was omega-3 fatty acids, you could use gas chromatography on a FAMEWAX(after FAME conversion) column and separate out what you're looking for based on elution times. The method for quantifying each material is going to vary based on its chemical/physical properties, so I don't think there will be a catch-all answer here.
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Why does water conduct the electrical charge from a lightning strike along the surface only?
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[According to Don MacGorman, a physicist at the National Severe Storms Laboratory in Norman, Oklahoma: “Basically lightning stays more on the surface of the water rather than penetrating it. That’s because water is a reasonably good conductor, and a good conductor keeps most of the current on the surface.”] (_URL_0_). Also see [THIS] (_URL_1_). And [this old thread] (_URL_2_)
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[This](_URL_0_) might give a clue. The skin effect basically says that most of the energy associated with the lightning strike will dissipate through the surface of the water. I understand it says AC, but with something like a lightning strike the assumption behind alternating current would probably still hold. It is a strike that pulses to a high voltage, then a sharp decrease in voltage because the lightning strike is over.
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Why is blasting an earth-ending asteroid into pieces so readily dismissed?
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First, not all asteroids are composed of the same material. A primarily rocky asteroid would be affected differently than a primarily metallic asteroid. So you would need to know a lot about the asteroid (density, etc). Second would be accuracy - you again need a huge amount of data to determine just where the most effective strike area would be (if there is any). Third - you have already pointed out - you are making many missiles - and you have no guarantee that they will be small enough to burn up. This means many more than a single strike target. So there are a great many variables - most of which you can't influence accurately. A better approach is to nudge it ever so slightly, far enough out, as to miss the earth. There are many ways this can be done (including with nukes).
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There is no plan to destroy asteroids. NASA tracks near Earth asteroids: _URL_0_ There is a committee that comes up with ideas as to how to respond to potential threats; Neil deGrasse Tyson is involved.
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when doctors declare that someone “died instantly” or “died on impact” in a car crash, how is that determined and what exactly is the mechanism of death?
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Emergency Physician here: The most common mechanisms of “instant” death are catastrophic brain injury or aortic tears/transection. There is a single tethered point left over from fetal circulation called the “ligamentum arteriosum” that used to be a fetal blood vessel but is not part of extra-utero circulation. In sudden deceleration injuries (like crashing a car into a tree) all of the internal organs continue to move forward for milliseconds (and millimeters) but since the aorta is anchored at this part (right after the arch), this part is still but the parts above it and below it move, which creates sheering forces causing it to tear. Every once in a while, these tears are contained but surrounding tissue, but most people will bleed to death into their thoracic cavity in seconds to minutes.
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Instantaneous destruction of the brain would likely not register. It's hard to say definitively, but by basic logic you can see that if a well placed blow to the head can render someone unconscious, then an exploding brain would be unconscious from the start. The brain is also a highly delicate organ, floating inside a pressurized fluid sac encased in bone; it doesn't function well outside a narrow range of ideal conditions. In the case of the gunshot, it would depend on the location and extent of the damage. There is a report of a person having a railroad spike (see: [Phineas Gage](_URL_0_)) through their brain with changes in personality and impulse control, but not death.
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Only 12, or 27%, of America's 44 Presidents have not served in the military. Is this exceptional or about standard among presidents and prime ministers around the world?
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The US has actually only had 43 individual presidents. Yes, Obama is the 44th President but only because there was a US President who served 2 non consecutive terms so he's counted twice.
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Well, let me list the final approval ratings of all Presidents since Truman. * Truman: 32% * Eisenhower: 59% * Kennedy: 58% * Johnson: 49% * Nixon: 24% * Ford: 53% * Carter: 34% * Reagan: 63% * Bush I: 56% (34% in the final poll before the election). * Clinton: 66% * Bush II: 34% I suppose there are three Presidents who ended their terms with low approval ratings that are removed from office long enough for us to judge them. Truman's is generally considered to have been a very good President. Carter isn't. Nixon's legacy is overshadowed by Watergate and he is generally ranked poorly because of that. I think a lot of Presidential historians would argue that other than Watergate, he was pretty solid.
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If a large percentage of CA's population moved to other states, would it help alleviate the drought and/or create drought problems in other states?
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We have enough water for California residents. The problem is California feeds a large part of the country with agriculture and agriculture uses the bulk of our water.
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> Why is there such a large distaste from Northern California towards Southern Cali about water? Essentially because SoCal would prefer to just take water from other regions, rather than reduce usage or tackle waste. In particular, no one in SoCal wants to tell the farmers to stop growing such insanely water-intensive crops in the middle of a desert. NorCal is also stressed by the same drought issues, but they've actually take steps to address the issue overall. The other states supplied by the Colorado River (which is the primary source for water for San Diego and Los Angeles) have taken steps to reduce their water usage as well, it's just that SoCal doesn't feel like changing.
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Why does flicking a small insect not kill it? Is the force not as strong as squishing it?
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It's mostly to do with mass. The less mass an object has, the easier it is to accelerate (so more energy goes to actual movement, and less to the object deforming.) Insects have very little mass, so they don't experience much resistance to acceleration (the flick.) Alternatively, squishing against a hard surface results in most of the energy being used to actually deform the insect, as it doesn't have anywhere to accelerate to.
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There are several factors at play here: - The square-cube law shows that force does not scale with size; that is, larger objects tend to not resist stress as well as smaller ones. (Hence why big cars perform poorly as compared to smaller cars in crash testing, why a building would fall if you built a larger scaled version of it, etc.) - Because the insect's mass is so low, it will have proportionally high acceleration for a given impact force, meaning it can effectively "roll with the punches." - And as you mentioned, the flow attached to the hand will create a cushion for the insect, spreading the force over a greater distance, and reducing stress on the bug. There was a long thread on this last summer [here](_URL_0_) if you want further reading material.
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Why is a Pint of Guinness so much better in Ireland/NYC/London etc. than my suburban bar?
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I haven't been able to verify it myself to take this with a grain of salt. Guinness in Ireland or other more populated areas will be fresher and will end up tasting better. A pint of Guinness at your local suburban bar will be shot out of a keg and through lines that have had older staler Guinness in it for much longer than a keg in a bar where more Guinness is consumed much more quickly. Basically, the Guinness in your suburban bar is more likely to be old.
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I imagine in the hotter areas it is because the heavier and more alcoholic ale is no where near as refreshing. That is just speculation though, I'm looking forward to an actual answer lol.
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What are superdelegates and what does it mean that Hillary already has so many?
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At the Democratic National Convention, a group of people called "delegates" will decide who the Democrats will run for president. About 80% of these delegates are elected by Democratic voters in primary elections and caucuses. The other 20% are not elected by voters, they are made up of prominent Democratic politicians and party officials. Most of these are backing Hilary, which puts Bernie at an automatic disadvantage. It means he doesn't have to just win more primaries than Hilary, he has to win a lot more and by a wide margin.
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Basically, it's a way to collect money for candidates. A PAC has some regulation to it and it needs to document and justify all incoming and outgoing money. A SuperPAC is a PAC with an extra cover letter attached when it's formed, and is nearly unregulated. You can pretty much give unlimited amounts of money to a politician in this way. Stephen Colbert formed one to show people exactly what you can do with one. [Watch this and then laugh, and then realize what it means, and then cry](_URL_0_)
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How does internet security work and how can hackers steal some info, like credit card numbers or medical records?
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Internet "forces" computers to be connected to each other; banks have to talk to each other to transfer money, hospitals have to talk to each other to transfer medical records that are needed, etc. "Security" is about making sure that only authorized accounts get access to the data. ID's, Passwords, log in policies, address-based restrictions, etc. It gets very complicated, because for example a hospital can have hundreds of doctors, nurses, and other staff who need access, so you have hundreds of accounts that have to have access. Hackers find a way to break in, either by stealing passwords, or by social engineering (they call someone pretending to be their boss or a different doctor and in a hurry to get in or the patient will die, and ask for a password), or by using bugs in the system that haven't been fixed yet.
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ioneupyourstory pretty much got it. but, to explain like you're five: Every computer has an internet talking box inside,or attached.This is called a network card. Every network card has a unique code -kinda like a computer fingerprint. This is called a "MAC" or machine address code. If you go get stuff illegally at a public network site, they can keep a picture of your MAC/fingerprint. The company that fuels your home network (internet service provider) usually also has a copy of your MAC/fingerprint. If lawyers somehow learn that someone was naughty at the public site, they can get an order from a court, and ask every major internet service provider in town for the matching MAC/fingerprint, home address, and name of the person on the account. From here, comes trouble. one more note: very sneaky people can change their MAC/fingerprints when out in public, so they are harder to catch.
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Is there a maximum distance at which the Earth's gravity can't affect an object?
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As far as we know, there is no limit to the distance at which gravity affects objects. However, the strength of the force of gravity decreases with the square of the distances, so it goes down rapidly. And at large distances, the effect is negligible compared to the effect of gravity from more nearby objects
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In short, there is no absolute limit. However due to relativity and laws of causation there actually is a limit given by the speed of light. That is to say if Earth magically doubled in mass in an instant(t=0) observers at varying distances from Earth would feel the increased gravity a some time t > 0 depending on how far they are from Earth. Thus there is some distance limit on the effect of gravity if you include time. This concept is actually the basis for the ~~theorization~~ explanation of [Gravitational Waves](_URL_0_) [~~Gravity Waves~~](_URL_1_).
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Is there an optimal method for untangling two things (e.g. Headphones)?
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Two separate pieces of string do not have the same topology as a pair of headphones, so this doesn't strictly apply to that case. But for two separate pieces of string, their tangling can be represented as a rational number. 0 or 1/0 both represent an untangled state, and other states are composed of a sequence of twists and rotations where a twist t(x)=x+1 and a rotation r(x)=-1/x. So you if the tangle is loose enough for you to determine the equivalent diagram, and consequently the tangle fraction, calculating the sequence of twists and rotations to untangle it is a process very similar to Euclid's algorithm for calculating GCD. [Here's an accessible paper about it.](_URL_0_)
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All of the waves from the different instruments add together into a single wave. It's actually kind of interesteing that even though they're all just added on top of each other our ears and brain are able to pick the different sounds out from the mixture. Mathematically you can see how this disentangling is performed by a fourier transform.
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What is cancer exactly ?
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At it's most basic, Cancer is a cell or a group of cells that no longer abide by the rules of that cell. They continue to grow after they are supposed to die, they ignore chemical signals your body sends telling them to not get larger, not change shape or to simply die. This causes a lot of problems because they are still considered by your immune system as a part of your body, so your immune system does not recognize them as something it needs to eliminate. This allows them to continue to grow and spread to other cells. There is no *one* cancer. There is no *single* cause. There is no one *cure* for Cancer because they are not all the same.
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[This comic](_URL_0_) explains it well. "Cancer is not one disease"
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Some medical ailments, like heart attacks, list "a sense of impeding doom" as a symptom. How does this feeling occur?
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Your body realizes subconciously (sometimes even conciously e.g. many people ascociate chest pain that radiates to left with a heartattack) that something is wrong and releases massive amounts of stress hormones (epinephrin, cortisol, ...). It is believed that the high levels of these hormones lead to deadly terror or a sense of impending doom. Additionally these hormones may lead to further decline of the vital functions, which is why sedation or morphine is a part of MI-treatment. Source (sadly in german): [Todesangst](_URL_0_)
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It's a minor fight-or-flight response. Evolution has conditioned us to avoid potentially threatening situations so that we can survive and breed. When you experience, see, or even read about a potentially threatening situation, the parts of your brain that control fight-or-flight (the oldest, "dumbest" parts of the brain) don't make the distinction between fantasy and reality. It perceives a threat and begins the body's fuck it up or get the fuck out reaction. Part of that is dumping adrenaline and your body producing cortisol, two hormones which affect the digestive tract. The smarter parts of the brain however DO recognize that the threat is not really real and the body doesn't, under normal circumstances, go full throttle fight or flight. Conditions such as PTSD and anxiety can and often will result in a full-fledged fight or flight event. In these circumstances they are known as a panic attack.
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The next test launch of the Orion space capsule isn't scheduled until 2017. Why so long until the next test launch?
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_URL_1_ The next mission (2018) is using a new rocket, the SLS Block I. The launch today was using the old Delta V rocket. _URL_0_ These rockets just started construction last month, so it's not unusual for a few years to construct the rockets and test them before using them to launch a payload into space.
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_URL_0_ The space shuttle was retired in 2011. Orion is the planned replacement for it.
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How come Jewish Chaplains in the US armed forces are identified by both the Star of David and the Ten Commandments, and not just the star by itself?
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Not necessarily. The Ten Commandments, particularly as enumerated on two tablets, have long been closely associated with Judaism. Many synagogues use it, and it appears regularly in Jewish art. Regardless, the Jewish chaplains were consulted in developing the insignia, so clearly the people involved thought that this was the way to go.
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Military chaplains were, and still are, commissioned officers of the armed forces. They wear miltary uniform but count as non-combatants much as medics do. This is the case for the American and British forces- and the Germans too. I have an idea though that the French chaplains were un-uniformed at least in WWI. [Here's](_URL_0_) the history page from the British army chaplain's department.
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Is there a prioritisation that the body has for instances where the body has less blood than it should in terms of how much oxygen each organ should take. would the brain assign itself highest priority or does each organ still just try to take the same amount of oxygen regardless of bloodlevel
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Yes. The brain requires about 20% of cardiac output at rest. Its requirements do not change as it is very sensitive to any periods of loss of blood flow and therefore loss of glucose/oxygen. In periods of severe blood loss there are autoregulatory mechanisms that alter blood flow to the other organs to a greater or lesser extent in order to maintain blood pressure to perfuse the brain. This is usually by constriction of the arteries supplying the organs in question. Often this is at a cost to the organ involved e.g. the kidneys and liver can be damaged relatively easily by periods of underperfusion, however this is preferable to brain damage as those organs are also very good at healing themselves whereas the brain is not.
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There are what are known as feedback mechanisms that control this. Here is a webpage with some details: _URL_0_ Here is an excerpt that explains a bit about how the body regulates how much of each type of blood cell to generate. When you lose blood in a accident or after donation, you have fewer red blood cells, which can then transport less oxygen. The lower oxygen levels stimulate the kidney to make the hormone erythropoietin, which then stimulates teh stem cells in the bone marrow to give rise to more red blood cells. > When the oxygen content of body tissues is low or the number of red blood cells decreases, the kidneys produce and release erythropoietin, a hormone that stimulates the bone marrow to produce more red blood cells. The bone marrow produces and releases more white blood cells in response to infections. It produces and releases more platelets in response to bleeding.
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Is there a reason we write $100 instead of 100$?
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It's to do with writing checks or invoices, if I recall correctly. By placing the dollar sign right before the first number ($100.00) you prevent people from adding a number before the 1 (Example: $100.00, 2100.00$)
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Because "18 hundred" is shorter than "1 thousand 8 hundred". On the other hand, "20 hundred" is longer than "2 thousand". After 100 years however, you will hear people say "21 hundred" instead of "2 thousand 1 hundred"
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Can we really clean pesticide off fruit by just rinsing them off? Wouldn't that mean rain would rinse it off all the time?
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You're not cleaning off the pesticide. You're cleaning off dirt and other toxins that may have stuck to the wax they put on the fruit to make it shiny. Pesticides stick to the fruit, but they are also absorbed by the plant and end up within the flesh of the fruit.
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Until anyone explains how fruit trees work in regard to water pollution, it may be of interest to consider that some plants actually concentrate contaminants. [Brazil nut trees](_URL_0_), for example, draw radium, selenium and barium from the soil, and Brazil nuts register (if weakly) on a Geiger counter. Some plants concentrate heavy metals to the point that they're planted to clean contaminated soil, a process called [phytoremediation](_URL_1_).
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Who was Anwar al-Awlaki
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Anwar al-Awlaki was an American (Who was also a citizen of the country 'Yemen') muslim cleric (holy man), who was said to be a nasty man who told other nasty men to kill people. America did not like him because he told other people to kill people, so they wanted to kill him before he could hurt other people. So a few days ago, they made a deal with the government of Yemen to kill him. Some people think that this was a mean thing to do, and that he deserved to be put on trial, and maybe sent to prison instead.
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My guess would either be Muhammad Abduh or Jamal al-Din al-Afghani... but there were lots of 19th century islamic scholars advocating that sort of thing
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If the troposphere can extend twice as high above the equator as it does above the poles, why don’t we have wildly varying barometric pressures between the two places?
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> Given that you have more than twice as much air So this is incorrect. There is more or less the same amount of air above the equator and the pole (to within a very slight correction for Earth's oblateness and centrifugal force). That's exactly why the pressure is more or less the same at both locations, since pressure is just the integrated weight of the air above a given area. Just because the tropopause (the top of the troposphere) is at a higher altitude in the tropics does *not* mean that there's more air there. It just means that the tropics are being heated more from below, which is exactly what we expect for a location that receives more sunlight. That raises the height of the tropopause, which is defined by the minimum of temperature found between the troposphere and the stratosphere. You can also see this in the equation for [scale height](_URL_0_): H = RT/g. Increase T, and the size of the scale height (how high you need to go before pressure drops to 1/e = 37% of what it was) also increases.
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To briefly describe it a High pressure system in the temperate latitudes typically means that there will be few or no clouds and light or no wind. So now the sun can heat up the earth very easily and so the temperature for that day is hotter. Not so much ELI5 but a column of air always weighs the same no matter what the temperature is. If it is a hot column of air it just takes up more volume, it cannot expand outwards as it has the same pressure as its neighbors, so instead it expands upwards. The upper limit of the lower atmosphere (tropopause) actually drastically change in height depending on where in the world it is. At the Equator the top is at about 56,000' and at the poles around 20,000'. Source: Me (2 years of university Meteorology)
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What do we know about the effects of long exposure of the human body to high gravity?
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Nothing. The highest gravity setting we have is 1G. We have studies on less than 1G. But we would have to go to jupiter or any planet with a higher gravity field to get long term studies. Being in a cockpit and pulling 4Gs isn't the same. It last just mere seconds.
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Radiation damages your DNA, which has negative effects on your body especially the immune system. People exposed to high levels of radiation will get radiation sickness, which is characterised by nausea, vomiting, bleeding, seizures, and eventually death. Even higher doses of radiation will kill you instantly. Your neurons are destroyed, putting you into a coma, losing all muscular functions and death is certain.
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What is a mole in chemistry?
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A mole is a number, like a dozen or a gross. Specifically, it's about 602,000,000,000,000,000,000,000 or, as we normally say, 6.02 times ten to the 23rd. (When writing with a pen, I write 6.02 x 10^23 ; on computers, I usually write 6.02e23) It's special because it's the number of Atomic Mass Units (AMUs) in a gram: if you know the molecular weight of, say, water, is 18 (AMU), then you know that 18 grams of water have 1 mole of molecules in it.
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"Mole" is like "dozen." If you have a dozen eggs, and a dozen basketballs, and a dozen lemons, you still have twelve all of these things. They weigh different amounts, take up different amounts of space, etc, but there's still twelve of them. Now, instead of twelve, use 6.022 * 10^23. Instead of "dozen" say "mole." There you go.
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During a commercial flight, is the angle of the surface of water inside a bottle a fair estimator for the planes pitch?
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Yes in Pitch (with deviations during speed and altitude deltas), No in Roll. Modern commercial airliners are flown banked such that the centrifugal vector is offset by the roll of the aircraft, or conversely, any roll of the fuselage is offset by centrifugal turning force... thus for a properly flown (Aka coordinated flight) aircraft, the fluid will vary on the longitudinal axis based on the aircraft's Angle of attack and thrust/decelleration vectors, but not along the Lateral Axis.
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Of course, the pool of water has some depth. The exact depth would depend on the interaction of the liquid with floor. You would probably have to specify the contact angle to make a precise calculation. The contact angle would depend on the exact composition of the liquid (add a tiny part of soap and it could change the result) and the composition of the floor surface. There's a lot of information here _URL_0_ if you want to read more.
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Are there any other elements besides carbon capable of forming the bonds needed for complex life?
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There has been some theories of silicon based life. It is similar to carbon, but the bonds aren't quite as strong. Obviously there's no proof of it, but from what I've read it's the most probable element behind carbon.
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All life we know is carbon-based. It has been theorized that there could exist silicon-based life forms somewhere in the cosmos, but as we have no evidence of any such life form having ever existed, it is an argument confined to theory.
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When I look at the shadow of a flame why do I see "waves" coming from the flame that I can't see coming from the actual flame?
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The flames cause the air near it to heat up. This air rises in a convection current. Air that has been heated is actually less dense than air that is cool, so light coming from the sun goes through the more dense air and travels into the less dense, heated air. Thus the light is *refracted*, or it is bent. This effect is noted in the wavy areas above the flame.
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Heat inside the air cause movement within the air, which can (in great enough temperatures) cause the light passing through the air to bend. In close proximity, you will see this as a smoky shadow being cast. Farther away, you will experience as mirage. A full refraction of the light that causes a wavy reflection on the surface, as if the road or desert is covered in water.
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Those random muscle twitches you get in your arms and legs
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Fasciculations. Fasciculations are caused by something irritating the nerve fibers and can just kinda happen. There isn't one specific cause for this, but the majority are benign and pretty much no one has any interest in studying the majority of causes. Some Fasciculations can be the result of a health issue (including medical side effects), but for the most part it's just something benign going on. For the sake of keeping this short I'm going to let someone else cover the health issues. So yeah, basically, just something irritating nerves and causing random twitching and there is no one reason.
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What you're talking about is called a *myoclonic jerk*, or *myoclonic twitch*. When falling asleep it's more specifically called a *hypnic jerk*. It happens to everyone from time to time and doesn't have any specific known cause in otherwise healthy people. If you're experiencing them frequently or have concerns, you should definitely see a doctor, of course. More info here: _URL_0_
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Why was it common for American southerners to speak broken, improper English?
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I'm assuming that you fail to understand that "broken, improper English" is and *was* spoken over the entire United States. For that matter, broken, improper English, is spoken all over England, itself. The fact that you have specifically targeted Southerners, hints at a possibly subtle prejudice. But to clarify a point, the development of any language is driven by the "broken, improper" use of the language. An example one can easily observe is the use of slang. If a terminology that initiated as slang is perpetuated long enough, the term eventually comes to be considered part of that language. Hence, the slight irony many English teachers face when confronted with the use of slang. It can represent the slow debasement and erosion of the English language, yet also can represent some of the elemental origins of the very language they espouse.
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For a long time, the South had many many rural areas that didn't have as much access to education as the more populated northern areas. So while the North had a relatively consistent exposure to the rules of English language, the South did not. So while it was literally true that many from the South were uneducated, it fed into a false stereo type that they were unintelligent because to northerners "they talk funny".
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How are Prime Numbers used for encryption and security?
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The number one rule of encryption is that it needs to be easy to do if you have the secret and hard to do if you don't have the secret. For a computer, multiplying really big prime numbers is pretty easy. Getting the prime factorization of really big numbers is hard. So we take two very large prime numbers (and by very large, I mean about 1000 digits is considered safe). We do some math on them to get a third number. Using the third number, there's some steps you can follow to encrypt the message but you can't decrypt the message unless you know the two original numbers.
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Two part answer to your question. 1) The key, used to encrypt a message, is produced by mathematic algorithms that use prime numbers. If you don't use a prime number, then any factor of the number can be used to "break" the key. For example, if I use the number 12 to generate the key then the numbers 2, 3, 4 or 6 can be used to "break" the key. A "good" key is one that is longer than the protected message. Once a key repeats, it is easier to "break" an encrypted message. A large prime number allows for a longer key. 2) To "break" a key, you have to determine the prime numbers used to generate the key. It is relatively easy to generate prime numbers, but it is much harder to factor large numbers into primes.
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TIL that more than 2,000 nukes have been exploded in the past 70 years. How are we not in nuclear winter?
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Those nuclear weapons weren't all detonated at the same time, which would put massive amount of dirt and debris into the atmosphere and block the sun, which causes the nuclear winter. Also, the nuclear weapons were of varying sizes, detonated in different areas of the world (including underground and under the ocean).
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Nukes generally explode over their target as opposed to on it as it causes more destruction so they already do.
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What was the reaction of the American public when Jacqueline Bouvier Kennedy married Aristotle Onassis?
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I always heard the marriage was not consummated and was strictly a means of supporting her after JFK was assassinated. Is that true or was it a media cover story? Was Onasiss a friend of the family when JFK was alive? Was the marriage based on some sort of chivalrous tradition?
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Joe Kennedy had a lobotomy performed on his oldest child, Rosemary (sister to JFK, Robert, Ted...) when she was around 22 or 23. It left her with the intellectual ability of a 2 year old.
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Would it be possible to have more than one Internet?
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Yes. The internet is just a network of computers. A very large network, but a network just the same. Creating your own Internet is as easy as unplugging your router from your modem. You can do all normal Internet stuff provided you don't need to talk to any machines outside your network. Now, in general, you wouldn't want to do that. There are some specific reasons to be completely cut off from the Internet but according to [Metcalfe's Law](_URL_0_) the value of a network goes up with the square of the number of users. So, it's easy to create a separate Internet but there is basically zero value in it.
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The word 'internet' refers to a network of networks, not all of these networks are connected together, but they all use the same technologies. It's just a way of connecting computers together (I don't know the tech in much more detail than that) and maybe there are others, but this system has a massive monopoly.
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The movie San Andreas: Is a natural disaster like this truly a potential threat?
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Honestly, no. Earthquakes are real. But obviously Hollywood hams it up. - Sharks aren't as big as Jaws - The T-Rex and Raptors in Jurassic Park were larger than actual size. If you really want to see an earthquake, there's plenty of online footage. _URL_0_
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The erosion that documentary was likely referring to would be caused by dozens of storms over hundreds of years. The flooding of the subway would likely only cause damage to the subway, not buildings above it.
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Why do I always see empty cars on the side of the highway with rags/plastic bags out the window?
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those are broken down/out of gas cars and the bag is supposed to indicate that the car isn't abandoned and someone will be coming back for it
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There are sensors on the road. Have you ever seen [those circles covered in rubber?](_URL_0_) Whenever you drive over them it let's the traffic light know there's a car there.
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How can open sourced encryption algorithms be safe from hackers? (i.e. Bitcoin)
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You don't have to reverse engineer anything - You have the blueprint in front of you. In true encryption, truly secure software, the only thing that is secret is the randomly generated keys, and these are not in the source code - they are generated randomly when the software is used. These keys are what is used to secure the system, not hidden tricks in the source code.
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> If the code is available doesn't that mean malicious people can find the vulnerabilities more easily? Yes it does. But on the other hand, if malicious parties can find out the vulnerabilities, so too can people who are actively working to make it safer. Remember that your average malicious hacker, notwithstanding a few talented individuals, isn't some genius as portrayed by Hollywood but someone who'll use things others have discovered in a mechanical fashion. Many of the truly talented ones have found their way into security jobs with big companies, and their interests lie in getting paid at the end of the month rather than trying to hold the industry to ransom.
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