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9mxf8l | Other | I really truly don’t understand what “gaslighting” is, other than it is a form of psychological abuse, what is an example of such behaviour? | It can go beyond these excellent examples, however true gaslighting manipulates the physical surroundings in the sense that say I hide something, allow you to look all over for it and then put it somewhere obvious or where it should be. It goes beyond making you question your sanily as its more intentional. | 9 |
9j8lef | Culture | How is movie/theatrical makeup different from consumer makeup? Why don’t actors rub it off or smudge it when they touch their face in a scene? | Theatrical makeup is the same for a lot of actors. There are ways around rubbing it off. One of my recent experiences was at a place that used a type of spray to keep makeup on us. For films it's a bit different as there are makeup people on hand to touch up any issues in between takes. It actually gets kind of irritating, you've just finished a good take, you've been given a good set of notes and the cameras have been set for another go or a different angle, and you get someone rushing in to brush your face or pat your hair down. It's something you have to get used to, and to be honest, I found I quite enjoyed having powder applied to my face. The brush is one of the softest things I've ever touched! | 3 |
8v4e05 | Other | Why is "IMBD" considered more official (or truthful) than "Wikipedia", even though both can be edited by anyone? | First, you'd have to identify who thinks IMDB is "more official or truthful than Wikipedia." | 4 |
9tewt4 | Biology | SERIOUS: Why does an alcoholic get a red nose? (This is not a joke, even though it sounds like a joke.) | As others have said, alcohol dilates blood vessels in your extremities. Over time, this repeated vasodilation causes delicate capillaries to be damaged and stay permanently enlarged and dilated and blood pools there, making your nose permanently red and giving you visible, swollen capillaries that are very noticeable on your nose where they are very close to the skin surface. | 3 |
8lt77i | Other | If all of today's continents were clumped together as Pangea 335 million years ago, did the imbalance of mass affect Earth's orbit? | No, because continental rock is lighter than oceanic crust, but also thicker. In general, there is the same weight of lithosphere (the uppermost layers of the Earth) everywhere at the surface of the Earth. | 8 |
b6kv4d | Technology | How is a heart transplant possible ? I mean, during a heart transplant I assume there's a moment where the patient's heart is removed to be replaced, how can the person survive without a heart ? | They use a technique called "cardiopulmonary bypass," which is a mouthful, so it's often just called "bypass." The patient is hooked up to a machine that pumps blood for them, so that the heart can be safely operated on until the problem is solved and it can be reconnected to the body's blood supply. So for the period of the surgery, the heart is being "bypassed" thanks to this machine, and blood can keep flowing through the patient's body. The rest of the body doesn't care much what's doing the pumping, as long as oxygen-rich blood is flowing. | 2 |
h7htw9 | Other | What is the difference between a proverb, aphorism, epigram, and adage? Math major here haha. Are they not the same thing? | A proverb is typically a memorable, commonplace piece of advice: "Never wake a sleeping bear." An aphorism is more an observation: "A bear in spring is always hungry." An epigram is made to be clever or funny: "Always respect mother nature. Especially when she weighs 400 pounds and is guarding her baby." An adage is similar to a proverb, but tends to be less poetic and more of a definition: "The best way to be kind to bears is not to be very close to them." | 1 |
67mg0z | Physics | how tellurium 128 has a half life older than the universe itself. Weren't lighter elements created first? | (category: Physics) yes, lighter elements were created first, but that doesn't have **anything** to do with half-lives. heavy elements like tellurium are created when a star dies in a so-called supernova. half life is a statistical term, an atom can decay at any moment, the half life just says how likely it is. what the incredibly long half-life of tellurium 128 tells you is that it's "basically not radioactive and instead a pretty stable element", meaning you still find almost all of the tellurium 128 ever created. | 2 |
9tzxgi | Technology | How can my cellphone record and post nearly 4K video but CCTV cameras at legitimate businesses(banks, schools etc.) have such poor quality? I’m new here and not trying to troll. I’m also very familiar with cellphones. However, after watching this episode of Dateline I don’t understand how I can record and post near professional grade videos with my phone, and the cameras outside of legitimate businesses(banks, doors to apt complex’s, schools, etc) have such low quality?? How sway? | On top of other good answer, you would be shocked how old some of the computers and technology in use at major businesses are. If it's not gonna increase profits, the company probably isn't gonna spend more money on it. | 4 |
8appcz | Economics | Why did the US rely on Opec oil for so long when it's now an exporter? | Just to add on to the answer by u/SlammyDavisjr Oil production in the US from traditional sources peaked around 1970 while demand continued to climb. Even then, however, the US satisfied relatively little of its demand using oil directly from OPEC countries. However, OPEC acts as a cartel. Essentially, they behave as if they were a single producer and restrict output to raise prices and revenues. Since oil is a global market, the impacts of OPEC production decisions affect the price of all oil, not just that sold by OPEC countries. The US shale oil boom changed OPEC's ability to alter the price in two ways: 1. It simply brought more oil onto the market, which puts downward pressure on the price 2. The time and money it takes to begin to drill shale oil is much lower than traditional oil sources. If OPEC raised the price before shale oil, it would be years before markets would respond and other producers would start drilling to take advantage of the higher price. In the meantime, OPEC would reap the reward. After shale, a higher price would cause a much quicker (months instead of years) response from a price hike, leading the price to stabilize much more quickly. Additionally, the 80's when OPEC did heavily restrict outptut to defend its market share, it was ruinous to the Saudi economy as they lost a ton of market share and they basically decided that it wasn't worth doing this time. | 2 |
9r50k9 | Economics | Why does the lottery exist and where do all the profits usually go to? | Profits go to the state government, in most cases; typically they say that it funds schools. YMMV on how true that is. Like 50% of the total cost goes to the jackpot pool, and the other 50% goes into the government much like a tax. Lottery exists because it generates money and people like to gamble. | 1 |
5n58ob | Biology | Why do we find cockroaches so disgusting ? I'm really curious, since they don't sting or pose danger as other insects or animals. | That metallic smell is unnerving. I do not like how they show by their very existence what you thought your clean house was is not. My dad used to tell me stories about how he watched a roach crawl on a toothbrush and shit on it. Makes you wonder what they do to your face when you are sleeping. But the worst aspect in my mind is sometimes you know it is only going to get worse. Lived in an apartment once where the idiots there only sprayed the specific rooms with roaches. I saw a single roach on the first night. By the end of my lease, they were in my freezer and there was no place safe from them, and if I called the landlord or bombed the place, they were just going to come back. That sucks. Properly run complexes annually spray top to bottom the entire building. | 13 |
ci0syb | Physics | The physics behind seeing water on the road in a distance even though it’s not there. | It's because of light refracting through the heated air just above the surface of the road. Refraction causes light (as well as other things like sound and waves) to bend when they move from one material to another. The heated air is different enough from the cooler air above it (due to density and heat expansion, etc) that the light refracts. It looks wavy like water because the way the light is being refracted changes as the boundary of the hot layer shifts due to wind and heating and stuff. | 4 |
j98opp | Other | Why do lawyers have a bad reputation? I've wondered this for a while. I have a family member who's a lawyer. He's a nice old guy. He handles a lot of things like accidents, property disputes, divorces and helping people manage their deceased family member's money. But I honestly don't know anything about law. It bores me to death so I've never asked. If someone could explain to me like a five year old what makes so many people dislike lawyers, I'd appreciate it, thanks! | Lawyers are expensive (though usually not as expensive as not hiring a lawyer) and people need them generally during some of the worst and most stressful periods of their life. So your *best case* scenario with a lawyer is that you are forking over a bunch of money to them during a terrible life situation. The worst case interaction is that they’re attacking you during an already terrible life situation. | 15 |
ah4b39 | Other | How do companies determine barcodes for their products to make sure they are not identical to another product sold at a large retail store? | There is a UPC governing organization called GS1 which assigns ranges to companies (for a fee) | 2 |
9a7cdv | Physics | What is the difference between the curved glass of a car versus the curved glass of eyeglasses? | It's not just the curve of the glass in eyeglasses that makes them work. Varying the thickness of the glass is what makes corrections. Auto glass doesn't vary in thickness. | 4 |
bjwii5 | Other | Why do girls and guys have different shoe size measurement scales? | When mass-produced shoes first came out originally they was no standard for sizing. You went to the store, stuck one on your foot, and if it wasn't agonizing to wear that was what you bought. Sizes started out as being selected by the cobblers to be the size of the "last", which is the foot-shaped thing you build a shoe around. So a size 12 shoe might have nothing to do with an actual measurement but might actually be the twelfth last on the rack that the cobbler used. Eventually this led to some standardization, but countries all standardized on different things, like what distances were actually being measured and where they were being measured from. Including whether to start with the smallest common size being a 0 or a 1, whether to measure the size of foot a shoe is expected to fit or one of several measurements of the actual shoe, both inside and out, and how physically big each size graduation might be, in centimeters, inches or barleycorns (yes, that's a real measurement, which has standardized at 1/3 of an inch). So the real answer boils down to historical inertia. People got something that sort of worked, and although there are more sensible ways to size shoes, now it's too much of a pain to change. | 2 |
9oygyh | Biology | Why do our eyes water excessively as the weather gets colder? | The cooler weather - and more specifically, the change from a warmer environment - causes the tear ducts to constrict. The tears already in those ducts have to go somewhere, and leak out. | 1 |
c616rk | Biology | How do insects breathe? | It's pretty varied, across different insects. The common characteristics are that air enters the body via spiracles (basically holes in the exoskeleton, sometimes valved) and then flows through trachea (a network of breathing tubes) to the entire body. Entirely separate system from circulation. & #x200B; This is what limits the size of insects, they need surface area for spiracles, but body mass increases far quicker than surface area as they get larger. During periods with greater oxygen concentration in the atmosphere, you got REALLY big bugs like 9 foot millipedes... | 2 |
d4v06i | Physics | If the sun is constantly adding heat/energy to earth, then why has the temperature always stayed the same? | heat leaves via radiation = the same way heat gets to Earth from the Sun, despite no air between them. | 2 |
has8vz | Technology | Why are infantry still used in modern war despite drones and tanks? | Infantry take up space. If you want to control an area, you can't just blow stuff up. That causes destruction, but when the vehicle goes away, the enemy just comes back. You have to attack, which is hard, and then hold the ground. This way the enemy has to attack your entrenched infantry, which is hard. This is how winning works. | 5 |
6rvs6n | Biology | Why do we sometimes hear sounds coming from our stomach? Not just from hunger, but also random noises. And why do we hear those sounds but not other bodily functions? | The sounds in your stomach are the stomach pushing down the food into your small intestine. The stomach makes a sound when it is empty because it doesn't have any food to muffle it. Notice how when you are full, you don't hear that sound. I don't know what random noises you mention in your question, but one sound I heard from my stomach is water sloshing around. Obviously, this happens when you don't have much in your stomach except water. We hear sounds only coming from our stomach because we also have air in our stomach which allows the sounds in our stomach to bounce and echo throughout our stomach. Since our stomach is somewhat close to our skin, this sound is then sent out the skin and then you (and the people around you) can hear it. Hope this helped! | 2 |
6g03ug | Chemistry | The effect of ADHD medication (Ritalin) on those who use it, but haven't been diagnosed with it. CONTEXT: During a recent brief discussion with my doctor I asked whether there was a benefit for people who used Ritalin, but aren't diagnosed with ADHD. She responded by saying that there isn't one and that, that's one way specialists are able to tell, besides tests and what not. This comment left me somewhat confused as I'm aware that there is quite a large market around selling Ritalin/Adderall illegally, hence the heavy regulations on prescriptions. On one hand I know it's popular with university students to assist with studying, however, on the other hand I've heard that people abuse it to gain a high. QUESTION: Are the people who obtain and use it illegally for the assistance they gain with studying/working, people who have ADHD but haven't sought out a specialist to get a diagnosis. While the people who use it for the purpose of getting high do not have ADHD? If so, what difference in an individual's brain chemistry causes this drug to react to react differently for people who have it versus the people who don't. Tl;dr If someone gains the intended effects of Ritalin/Adderall does this confirm they have ADHD? And that getting a high from taking it, is indicative of not having it? If yes, chemically speaking, why? | I'm not any expert. I've had adderall two days in my life. What I've felt/experienced, is that the voice in my head that says..."you can do this later", doesn't exist. Basically, everything I think of doing while on the drug becomes nearly automatic. I'm going to sort these clothes, I'm going to clean this room, I'm going to run these errands. Very powerful, and I would use it again in the future, but not always. It's something I can see becoming very dependent on.... | 39 |
kedpta | Biology | I’ve always wonder why when you “step” in germs they don’t try to make their way to your mouth, and how is it different, when you touch your mouth with germs on your hand they know they have to go inside, but not when they’re on your elbow or leg. | Germs don't "know" anything. They're not sentient and have no objectives other than surviving, eating and reproducing. The insides of our bodies are extremely favorable environments for bacteria, so we have a lot of defenses to keep them out- namely, our impervious skin and immune system. Touching your mouth or any part of your face just transfers the bacteria that are happily puttering around on your finger to that area. The mouth and eyes are notable in that they're gateways to our insides that some bacteria could exploit to gain a foothold inside us. | 2 |
6hij13 | Culture | Why are hardcover books discounted so much more heavily than their paperback counterparts? Or is that not actually the case, and it's just some sort of anecdotal observation that I have made? | Because a hard cover books price is drastically inflated compared to paper back. It's usually the first run of a book so it's the maximum price they feel they can charge. Paper backs are cheaper to produce and generally come out much later, at a point where everyone willing to pay the full hard cover price already has bought it and the value of the book has dropped drastically already. Therefore the initial price of the paper back is always a lower initial price than the hard cover. | 2 |
aau0s0 | Physics | How do tsunamis work? Like when they say to run when “the water is receding,” what do they mean? | Think of the ocean like a big bowl of pho (beef noodle soup). The bowl itself is the shore line. As you sweep your spoon across the soup (we'll pretend the spoon is the force causing the tsunami in the first place), you'll notice the noodles/beef/garnish pilling up as it hits the side of the bowl. This is what's happening to the tidal wave as it hits shallow waters and the shore itself. So as you notice when you build up that pile of noodles/beef/garnish, the soup drains out behind it, filling up the space the noodles/beef/garnish left behind as it's beginning its gigantic build up in height. That's what's happening with the receding water. Eventually the momentum of the broth crashing into itself and more and more noodles/beef/garnish being piled on, it eventually reaches a height where it collapses over the side of the bowl and then there's your tsunami. | 3 |
8b0puy | Other | this picture disappears when you stare at it - why? | This is due to something called *Troxler's Fading*, which is the fancy name for the idea that if you stare at a fixed point long enough, all of your peripheral vision will eventually disappear. Normally this isn't an issue because our eyes are constantly shifting ever so slightly. This particular image works really well to show Troxler's Fading because it's vague and undefined, and the colors are just off of white, so the whole thing disappears much faster than other images might and we have an easier time focusing on a single point, without getting distracted by other details. *edit Also, it's known that a person who lacks certain cones in their eyes (a colorblindness issue, typically) will have greater difficulty (or even find it impossible!) in making that image disappear. | 5 |
6asqt4 | Biology | How can someone's DNA be 18% of sub-Saharan Africa? I thought DNA is split 50/50 between the mother and father's side. Speaking in reference to [this article]( URL_0 ) about a sergeant who recently discovered he's 18% sub saharan african. How does that come about? I have a rather rudimentary understanding of genetics, so I'm only really familiar with punnet squares. Would that mean that his great grandparent was African? In which case, shouldn't he only have 12.5% African DNA? | Your genome is split 50/50 between mother and father, but a mixed race parent (whether 50/50 or not) does not necessarily give 50/50 ratio of racially identifiable chromosomes. Any mix of chromosomes is possible, so the child might get only 8 of 23 'african' chromosomes and 15 'european' from the mixed race parent and end up with 8 out of 46 chromosomes with african markers | 2 |
asasma | Biology | what are electrolytes, why do they keep us hydrated and how do they add more to sports beverages? | Electrolytes are molecules that, when dissolved in water, allow an electric current to pass. Pure water has no electrolytes and doesn’t conduct electricity, but if you dissolve salt into it, you can conduct some electricity. Non-electrolytes, Luke sugar or alcohol, don’t have this property. Electrolytes are important because they are vital for muscle function- sodium and potassium cause your muscles to tense and relax when you move, for example. Electrolytes are in sports drinks because you lose a little bit of salt when you sweat, so the drinks give you some back. However, there’s some debate as to how much it actually helps. | 4 |
bt7gez | Biology | Why are crabs cooked alive? | Sometimes we clean them first (at the dock), then you don't have all the guts to deal with later. | 3 |
d9ws43 | Other | How does bacteria find it's way into other people's bodies when you sneeze while being sick and not just get lost in the environment? | The pathogen isn't just "finding" its way into people's bodies. A cough or sneeze creates a toxic cloud that lingers in the air. A typical adult male breaths in about 6 litres of air per minute, but if they're breathing more heavily it can be significantly more than that. Each breath taken in that toxic cloud actively sucks the pathogen into your lungs. From there the pathogen must break through the mucus layers in your pipes and lungs, and if they manage to do that then you become infected too. | 2 |
5pgpt4 | Biology | Why only children get lice? | It's not only children who get lice. Adults can, and do, get it too. Children are more susceptible because they often don't have the hygiene habits that adults have, and frequently share toys/clothes for games in which they dress up. | 3 |
f8gkdg | Engineering | How come stage lights make a noise when they are turned off? | They don't. That's just something they do in movies and TV shows for dramatic effect. & #x200B; What /u/ironhydroxide is talking about is the disconnect switch for the power taps. The lights themselves are not controlled by that switch. Instead most stage lights are either controlled by a professional dimmer system, or they have their own internal dimmers. That switch gets thrown well before the show starts and stays on until well after the show is over. It's true that older lighting systems used for small stages with low budgets might not of had dimming systems so the stage lights were either on or off, but even still they weren't typically controlled by relay systems. Source: I've worked in professional live events and theater for the last 25 years. | 2 |
fk6u1s | Other | why do people say Jesus H. Christ? | I believe that it’s to do with Equity naming. Look at Harry H Corbett, so named because Harry Corbett was sticking his hands up Sooty... When asked what the H stood for Harry H said “Henny thing” | 8 |
brexk1 | Engineering | How are really tall buildings able to withstand high winds? I live in Chicago and get super anxious when it's Windy out ( I know that its called windy for another reason but it was also WINDY recently). How is it that these tall buildings don't fall over, how safe should I feel? The swaying also bugs me out when I'm inside them. | Steel frames. They're strong. Tall Buildings are engineered to withstand a certain limit of windspeeds. Then engineering principles say to apply an amount of over engineering as safety factor, typically 1.5x or 2x But should we ever get the much speculated tornado that hits the Loop, no amount of over engineering will be enough. Something is gonna come down | 3 |
845hih | Repost | Why do some countries show pricing on the shelf excluding taxes? Where I'm from it shows the final price you will pay on any advertising and pricing labels which makes sense. | U.S. sales taxes are VERY Complicated. We don't have a national sales tax that applies evenly across the board. Sales tax goes down to the state, county, and even local levels. The tax you pay in one store could be completely different to the tax you pay in the store across the street in extreme circumstances. Plus the types of goods that are taxed also vary (some states charge tax on groceries, others don't, for example). Having to individualize all these different price tags would be a logistical nightmare. | 1 |
6bw1yl | Technology | How come hotel key cards get erased by being near cell phones, but credit cards don't? | FYI the tap-ability of your credit/debit cards can be ruined by your cellphone too. I've had it happen multiple times. | 7 |
f3mxlf | Culture | Why is it ok for buildings in New York(for example) to not have elevators in their buildings? | Accessibility is actually a huge problem! Many/most places are't accessible to many disabled people, even the ones that claim to be. For example, it's much harder to find a seat at the movies/theatre as a wheechair user because there are very few places you can park it (also, did you know? Many people leave the wheelchair and sit in the seat next to it). And if you're deaf, forget about captions. Disabled people have had to personally fight for every accommodation. If a building isn't accessible, it's because no one forced it to be. ): | 2 |
83jrfn | Physics | why "black lights" look purple? | Blacklight is actually ultraviolet light, slightly higher energy than visible light. When fluorescent surfaces absorb ultraviolet light, they give up that energy in two or more steps. One is in the form of visible light, which is what you see as purple, even when other luminous sources of light are turned off. The other step(s) are lower energy light that we cannot see, such as infrared. | 4 |
hl864c | Engineering | What is the most important algorithm in modern computer science? | Currently in Grad school for computer science. I can't really place just ONE important algorithm. What's more important is the efficiency of an algorithm. With the vast amounts of data being dealt with by companies/organizations/governments, you need algorithms who's growth rates grow slowly as the amount of data increases. In this vein, log base 2 of n efficiency is a great efficiency to shoot for when possible. So think of the binary search algorithm as a good example. | 1 |
kbkbsl | Biology | Why do we need to sleep so much, what happens in the body when asleep that cannot happen while normal resting or relaxing? Or is it just for the brain? | The question should be the other way around: Why are we awake so much? Being conscious and awake takes a lot more energy than sleeping. We have evolved to be awake just long enough to do all the things we needed to do to survive: hunt, gather, eat, mate, etc. What's it like to "notice" while you're deeply asleep that you uncomfortably twisted one of your joints and then, without waking up or disturbing your consciousness, automatically adjust your sleep position to fix it? Creatures such as [Jellyfish and bugs]( URL_0 ), have such simple minds, I don't think it's a stretch to say that they do everything "unconsciously" -- sorta "sleepwalking" 24/7 in effect. | 18 |
dfrm8j | Technology | Why are space missions to moons of distant planets planned as flybys and not with rovers that could land on the surface of the moon and conduct better experiments ? | The simple, non-scientific answer is: Money. It's much cheaper to fly by. Who is gonna spend billions to send a rover to a distant moon and why? The cost/benefit doesn't make sense. | 17 |
igpry8 | Economics | Swiss Bank Account Idk if this had been posted already, but can someone explain to me why Swiss bank accounts are so popular among the rich and/or fraudulent? I see it in movies and in the news from time to time. Someone puts a bunch of money away in a Swiss bank account. Why? | IRS: "Hey bank, I think one of your customers did something illegal, can I look at who he got money from?" Bank: "No" IRS: "But he's really really sketchy!" Bank:"No!" IRS: "Seriously, do it!" Bank:"Make me!" *Under most governments* IRS: "Hey, can you make the bank tell me, here's the stuff that looks sketchy." Most Governments: "Yeah, that's sketchy as hell. Bank! Do it or we'll do terrible government things to you!" Bank: "Fine!" *How the Swiss Government used to act* IRS: "Hey, can you make the bank tell me, here's the stuff that looks sketchy." Swiss Government: "No." IRS: "But..." Swiss Government: "No." Bank: "Sucks to be you!" But people got sick of it, so they made the Swiss government change it so they could tell banks to comply. Nowadays countries like Singapore and the Cayman Islands have similar laws to how the Swiss used to act. So they're becoming the place to put sketchy money. | 4 |
cveeoe | Biology | With all of our advanced code-breaking tools, why can't we understand and communicate with dolphins? | Because dolphins aren't like humans stuffed into dolphin suits, so large parts of their communication tend to revolve around actually *being* dolphins. A hungry dolphin might convey that by doing this things a hungry dolphin does, which requires being a dolphin. | 3 |
81ro11 | Physics | How does Flash Freezing work? | If you put a steak in a typical residential freezer, the freezer's air temp should be at about 0F or -17C, at that temp the inner portions of the steak will reach freezing temps fairly slowly. This allows ice crystals to form. The ice crystals will puncture the cell membrane and when the steak is thawed a lot of the water will leak out, carrying with it a lot of the flavors. In flash freezing, the freezer is extremely cold, depending on what's being flash frozen, anywhere from -100F to -300F. At that temp, the water freezes before it can form crystals. After the food has been flash frozen it can be stored at conventional freezer temps. | 1 |
8yvsrc | Biology | Why do babies cry as soon as they’re born, and why is it a bad sign if they don’t? The answer seems like it should be obvious, but is there something else going on that makes this such an important component of its well being? | It’s not a bad sign if they don’t cry, it’s a bad sign if they don’t breathe. What we want them to do is take a forceful first breath - sometimes that’s as part of a cry. This is to expand the lungs adequately to force out the fluid from the lungs opening them up for gas exchange and closing the foramen ovale. Source: I am a midwife. | 3 |
jgmcm0 | Engineering | why do bikes for men have that top tube in the frame? I understand why it would be easier for women not to have that high bar in the bike frame as it would not work with long skirts and dresses. But as the... area, so to say, is quite sensitive for men, why does their bike frame have a top tube? | A well fit men's bike should never really get in the way of their balls when standing over it. Stunt bikes tend to be very short, and mountain bikes need to be as strong as possible, which a top bar is. BMX bikes actually are made with a slanted top bar, specifically to avoid "racking" your nuts. The lower top bar (or missing top bar) was put in place mostly for women's fashion. Originally it allowed biking while wearing a dress. Later, tight pants. The low bar allows mounting without having to lift your leg really high. This actually makes women's bikes really popular with older women, who are (at a younger age than men) more likely to have hip mobility issues. The downside of a lower (or missing) top bar is that you lose a lot of the strength a traditional top bar adds to the bike. You're left with either a less resilient bike, a heavier bike, or a much more expensive build. When women still had to wear dresses, they were also expected to ride in a much more reserved manner, so the weaker frame wouldn't have been as much of an issue. You can still find modern bikes made with this lower or missing top bar, but if you look at top of the line women's road or mountain bikes, you'll find they look very much like a men's bikes. Giant's women's road bikes actually have a slight nod to the dropped top bar, with a slightly downward slanting top bar - which is more aesthetic than functional. Most of the changes have to do with the parts on the bike (special saddles, smaller gap between handle and brake or handle and shifters, and the frame usually accounts for a shorter torso. Generally, more ergonomic choices (though some cosmentic) and less... well sexist. For a casual bike to ride around town, where weight doesn't matter, a dropped or non existent top tube is going to be easier to get on and off, and more easily set to a variety of riders. In fact, many bike share companies choose this set up for that reason. However, once something is labeled as "women's" it is really hard to convince men to get over that trend en masse. | 5 |
6b2h20 | Other | What makes some whiskey/bourbon/scotch "smooth" and others "harsh?" Price is not the answer I'm looking for. There are affordable examples of each that are smooth, and others in the same price range that are harsh. Food science based answers would be the most helpful. | The aging process is what smooths out the whisky. As it sits in the wood barrels the whisky temperature fluctuations (driven by the changing of the seasons) cause the whisky to seep in and out of the wood. While this is happening, some of the ethanol evaporates off (called the angel's cut) through the wood. This drops the proof of the whisky, making it less harsh. At the same time, some of the natural compounds from the wood get pulled into whisky, giving it color. The longer a whisky is aged, the smoother it gets. As a barrel ages, more and more volume evaporates out. A 30 year old barrel of whisky might loose 3/4 of its original volume, which explains why it is so expensive. | 6 |
cg858k | Other | have languages for animals developed over time similar to that of human beings, or say can a lion in this time communicate with a lion five hundred years ago? | Humans have very, very complex vocal chords and languages. Lions have like 3 types of sounds and can't really build words out of it. And grammar and sentence structure is way beyond any animal outside homo can grasp. A parrot was taught to recognize like 100 words, chimps something similar. But that was trained behavior. And even chimps can't really vocalize anything complex. IMHO, the difference between Homo Sapiens and other Homo species might be the vocal chord. TLDR: I highly doubt hon-human language has anything meaningful complex about it. | 9 |
az2re6 | Biology | Why does covering yourself up with bedsheets to force yourself to perspire when you’re sick actually makes you feel better afterwards? | You’re not actually supposed to do this... your body knows what it needs, you shouldn’t be raising your temperature even more. Your body will raise your temperature on its own, it doesn’t need any help. | 11 |
8jp328 | Biology | Why is fire not dangerous to stare at, as opposed to something like the sun? (Ex: bonfires) | It’ll already be uncomfortable to stare at an uncovered 100W light bulb. Now consider that the sun is 3,800,000,000,000,000,000,000,000,000 times brighter than that bulb. | 3 |
6virlq | Economics | How does the derivatives market work? What are put options, call options, futures contracts and all the other stuff related to the derivatives market? Can I invest in it? | Derivatives are based off of, but do not consist of, another asset A call option means you pay a little up front for the *option* to buy an amount of a certain stock at a set price on or before a certain date. If the price goes above the set price you can *exercise* your option and buy the goods at that price, you can also close your position without taking possession of the stock, basically buying at the set price and instantly selling at the higher market price Put options are the option to sell at a fixed price. If the price drops below the set price you make money. In both the options, if the price is unfavorable at the end you don't have to follow through and are only out the small premium A Futures contract is an agreement to buy/sell at a fixed price on an agreed upon date. There is no option to back out if the price is no longer favorable You can invest in derivatives, but if you're asking here you're not ready yet. Derivatives increase your leverage so you can take a small pile of money and make it bigger quicker, but you can also lose it a lot faster. | 4 |
a57n4l | Biology | How do companies test to know how long their products last Deodorant, makeup, hair products all state their product lasts for X number of hours. How do they test for this? | I have no professional experience with any of this but I did manage to make a deodorant claiming to last 24h to actually last that long. Until recently, I would always carry deodorant with me to reapply during the day if it was a busy one. When I did some digging I came across articles that quoted dermatologists stating that you should use your deodorant before you go to sleep. Their justification is as follows: The point of the deodorant is to clog your pores to prevent you from sweating. Usually you don't sweat incredibly much at night so when you apply it, it has time to absorb into your skin. When you wake up and shower you won't wash it off since it had ample time to be absorbed. This will give you a near sweat-free day. If you apply it after the shower, the moisture on your skin will prevent the deodorant from being absorbed and will slowly wash it out. Also it wouldn't have time to properly absorb anyway before you already start sweating. Since I switched to this technique, I can go a hole day at uni and come home late without sweating strongly and as a plus without developing stains on my shirt (again this is because the moisture or sweat washed the deodorant into your shirt whereas if you applied it before sleeping, it had at least 6 hours to settle). Life changer in my case 😊 | 2 |
dh6qqy | Other | The reason ambulances don't always have their lights and sirens on when transporting victims of serious injury | For serious injury, sometimes a slow and smooth ride is more important than getting to the hospital quickly — especially if the EMTs are fully equipped to handle any time-sensitive problems that may come up. If the ambulance doesn’t have to disrupt traffic, the driver will keep the siren and/or lights off, just sounding momentarily to clear any intersections. | 4 |
6j2t9p | Other | How does my brain decide whether a repetitive song is catchy or annoying? | Those two things are not mutually exclusive - something can be extremely catchy and ALSO very annoying ([example]( URL_0 )). I'm not a music theory expert, but how catchy a song is I think is mostly dependent on simplicity and familiarity - e.g. a simple song is easier to remember and our brain tends to like things that are at least a bit familiar. Of course, *too* simple is boring and not mentally stimulating at all, so there is a bit of a balance. Annoying I think tends to be more subjective and down to personal preference. | 1 |
5q9hr3 | Culture | What does a misspelled word or bad grammar look like in Chinese? | In Chinese, we have what we called [measure words.]( URL_0 ) > "Unlike English and most European languages, Chinese does not distinguish between singular and plural, so nouns are simply abstract in number, with context determining whether something is singular or plural. But when you have to specify a certain number of something, you combine the number itself with a measure word, followed by the noun." In English, you ask "How many people?" In Chinese, it would be 几个人 (jĭ gè rén)? 几 is how many and 人 is person/people while 个 is the measure word for people. A lot of people who are learning Chinese for the first time tend to omit measure words. *** Also another common mistake would be the usage of number 2: 二 (èr) and 两 (liǎng). Using the previous example, if I was to answer "Two people," 二个人 would be incorrect. The correct answer would be 两个人. 二 (èr), is when you want to refer to the digit, for example when you are count from 1 to 10 or when you are telling someone your phone number. 两 (liǎng) is used when quantity is involved. Like the example I showed above, two people- 两个人. | 19 |
i38zgi | Technology | Why do you have to wait 30 seconds after unplugging something before plugging it back in? | Everyones going nuts about capacitors, but thats maybe 20% of the actual reason. The more common reason is that other devices need to recognize it is no longer there. You want to reestablish any active connections. This is why its very important for modems, cable boxes, etc. Anything where another device needs to recognize its 'gone'. | 16 |
83x59q | Economics | What is "leverage" in betting/investment? | The answer by /u/ceribus_peribus is correct, but I just wanted to expand on it a bit. So, as he says, leverage is borrowing in order to reinvest it something that will bring you more money. What you are doing is borrowing against assets or income you already have to get more money (for example, from a bank) than you can raise on your own. An example is let's say you own a home and have done a good job paying off your mortgage and/or the housing market has increased so the home now is worth $300,000 more than you owe on your mortgage. So you decide to refinance your mortgage (take out a new mortgage that pays off your old one) for the full new value of the home. But since you don't owe all that much, you take $200,000 of that mortgage in cash. You then decide to take that $200k and buy a parking garage that charges for parking worth $1million. You have a good credit history and that $200k in cash, so the bank gives you the loan for the rest, so now you own your home and a parking garage that can provide additional income for you. You *owe* more money in mortgage payments to the bank, you *owe* new loan payments for the garage, but you now technically own a nice business and a good stream of income and so are a much richer person (probably). All of this was done by having good credit and leveraging the increased value of your home into the new purchase. The leveraging could continue from there as well. You can leverage the parking garage into a new loan for another garage or a new business through various means (not necessarily just taking out loans against current businesses). At some point all this leveraging will be described as "highly leveraged" and will be bad because any ill fortune on any of your businesses will cause you to be unable to make payments on all the loans you owe. A good lender will look into all this leveraging and deny you for new loans. But realistically, lenders aren't always that diligent and borrowers aren't always that forthcoming. | 2 |
5pqjfl | Physics | The double-slit experimet. How can simply "watching" the electron cause it to stop being a wave? | The explanation with the photon necessary for observing the electron is a nice and kind of intuitive one. However, to my (admittedly limited) understanding of quantum mechanics after seven years of studying physics, the observer does not "need" a photon to destroy the wavefunction of an electron. In fact, this explanation is not that quantum mechanical, because if you look at the small scale, even classical physics would tell you that some object with momentum bouncing off of another small object would alter that momentum and therefore the experiment. (not if it's bouncing off a wave i guess, but you get what i mean) There's been experiments in which no direct interaction between the electron and the observer have had taken place, yet the mere ability of an observer to find out where the electron went made its wavefunction collapse (and hence the interference pattern disappear). I remember a paper that has shown that by bouncing off electrons of atoms. The subsequent wiggling of the atoms made it under certain circumstances possible to know which path the electron took. When these circumstances were given, there was no interference pattern between electrons. When they were not, the interference pattern appeared. I am really sorry for not being able to find that paper. I have no idea how to look for it. Quantum mechanics is extremely weird and everybody who tells you different is lying. I've been on a talk of Anton Zeilinger who said "To be honest: I'm perfectly fine with not understanding a thing in quantum mechanics". Note that he is probably the most famous quantum mechanics guy of modern times. The wave function resembles a probability distribution. Interference only takes place when waves are present. Once you (as an observer) eliminate the probability distribution by determining with certainty that a particle is somewhere there won't be interference. That's how I look at it. | 3 |
96w0tn | Biology | Why do you get the urge to smoke after drinking alcoholic beverages? As a smoker, I've always wondered what causes such a strong urge to light one up after a taste of alcohol, mainly beer. | Some good answers in the thread thus far, but I think people have missed a key point. Both alcohol and cigs release dopamine, hence the pleasurable feelings associated with them. So many people enjoy smoking when drinking as it increases the pleasure effects of both, ie a synergistic effect. More dopamine = more pleasure. | 2 |
a2jtjr | Biology | why does music make us feel different emotions? For example, certain tones in something scary to give you an ominous feeling. Music that makes you feel good in certain parts of movies to portray romance or a wholesome moment. | I don't know all the answer but I learned in music history class that there is a tune that is the doom tune. Basically one of the songs used in Catholic mass, the dilas irae, was a doomy part of the sermon I guess so when they wanted to write scary doomy music themes they used it. Sometimes its fast, like the tale of sweeney todd, sometimes its slow, but it's incorporated into the song somehow. It's been several years now since I learned this and everytime there's a doomy part of the movie that tune pops up. So, as to what this has to do with your question - I think some of it can be the history of a tune. | 3 |
5zwufg | Physics | Why do foods like rice, pasta, or beans take minutes to soak up water when it's hot, but hours upon hours if the water is cold? (Not sure whether to flair chemistry, or physics.) EDIT: Wow, this is the most rated/commented post I've ever made, thanks guys. I played GTA V for a few hours and come back to this. Thanks for the responses. | I've seen some answers about why starch specifically requires hot water, which are likely correct as well, but I'll provide an explanation via thermodynamics. In general for anything like this it is all based on diffusion. Diffusion generally refers to the movement of matter from a high concentration to a low concentration, so if you have a lot of water molecules in one place (i.e. water in a bowl) next to a space that contains very few water molecules (i.e. a dry grain of rice floating in that water) the water molecules will be more likely to enter that space over time, this is due to entropy of mixing (I can go deeper into entropy upon request but I'll spare you here, basically it is a numerical measurement for the reason that things mix together). This is why if you let even cold water close to freezing sit in a bowl with rice or beans it would eventually infiltrate them, but like you said it would just take a long time. Even cold atoms have energy, but that energy just makes them vibrate, not move with any kind of purpose, so the odds that they'll end up inside of the grain of rice are random. Now the energy of the atoms increased with temperature, which makes them vibrate more, which means that they are that much more likely to enter the grain of rice. The thermodynamics probably compound with any chemical reason for the starch absorbing water as well. TLDR: Hot things vibrate faster, faster vibrations increases the odds that each water molecule enters the rice over time. So hot water will enter the rice faster. | 8 |
606oqe | Culture | Why is the U.S. presidency referred to as the leader of the free world when there are plenty of leaders in free countries | After WWII the US was 50% of the world economy, a leader in tech/agriculture/medicine, and very vocal/forceful about democracy. Democracy being equated to freedom, the US being the lead democratic nation, it only makes sense that the title would be applied. | 6 |
6u7qh2 | Culture | How and why did "I have to" come into existence in English as a substitute for "I need to?" I can't think of any connection between the two and I was curious as to how the connection came about. | The earliest meaning of "to have" was "to grasp", way back, before English even existed. From there it took on many more functions. First, it started meaning "to own", which was not too far from it's original meaning. Then, it became an auxiliary (helping) verb: "I have seen him". This happened in Old English, during the Middle Ages. It then became a modal auxiliary, "to have to", also in Old English. *Why* this happened is unclear, as always in language. There have been similar developments in other languages with verbs like "to have", such as Latin and German. | 1 |
6e54ri | Repost | Why does tickling cause laughter? | I seem to remember reading somewhere about how being ticklish on certain parts of your body (belly, neck, armpits, etc) was actually an evolutionary thing that developed to teach children to learn how to protect their vulnerable spots on their bodies. I dont know if that's true or not, or if that explains the laughing part, but it makes sense to me. It's like, our bodies made it fun to learn basic self defense when we're young or something | 3 |
6i76uu | Mathematics | What makes physics engines for games more complicated than just applying the basic Newtonian laws of motion? | The formulas we have are not simple. Sure they are simple to solve for single point masses, but once an object gets larger than 0/infinity, the amount of computation power gets insane. It's kind of the same thing as if you started with one penny and doubled it every day for an entire summer you would have more than enough pennies to circle the diameter of universe several times over. To calculate just a dozen or so particles with full accuracy to model collisions in the large hadron collider it takes 6% of the world's entire computing power, and it can take weeks to calculate what happened over a second. The thing about physics engines is that the entirety of their programming is figuring out how to take a calculation that requires a computer the size of Jupiter to perform, and cut enough corners to let it run on a home computer. When we talk about physics engines in games, they are NOT modeling anything without huge compromises. For example when you look at a typical rag doll it's actually modeled as only 40 particles and then mapped onto an object that should be made up of quadrillion's of particles. Not only are we simplifying physics from a quadrillion to 40 particles, but even at that point it would cause a home computer to explode. So you have to severely round your calculations to a much lower precision, and throw out 99% of the atomic interactions like temperature, radiation etc. Instead of even modeling the friction when a bullet hits something for example it's just simplified into spawning the same explosion animation each time. So to summarize. A physics engine is complicated to program because it is literally taking a calculation that requires a computer hundreds of times larger than the planet, and figuring out exactly how to cut that down so it's usable without producing too many errors, and we still end up with a ton of obvious and hilarious errors. | 5 |
j7xhyp | Biology | Why does a woman stay awake during a C-section, but if someone is getting an appendectomy they will be put under, even though the appendectomy seems way less invasive? | My wife gave birth to all of our children via c-section. One of them was done with a general anesthetic because it was an emergency situation. The others were done with a spinal tap. For the one where they put her under, they had the baby out very quickly, like within a couple minutes of when she went to sleep. | 6 |
mdp9su | Chemistry | If smells are made of particles, where do they go? I was told in school that you can smell things because there's tiny particles from that thing in the air. So if for example someone was cooking a whole pan of garlic while farting like a trooper, and they opened the window to let the smell out, where do the particles go? Do they die or is there a giant stink cloud somewhere in the sky....? | They disperse and reach such a low concentration per volume of air that they become essentially undetectable. Like dropping a single drop of ink into a swimming pool. | 4 |
l8ieq9 | Biology | If mouthwash gets rid of 99.9% of everything compared to 50-60% with toothpaste - and there’s a noticeable difference - why do people still brush their teeth? | Mouthwash may kill a lot of the bacteria that are currently present in your mouth, but it doesn’t necessarily remove all the food or plaque on your teeth, on which further bacteria would then grow. As vigorously as you “swish”, you don’t generate enough power to essentially power-wash all the debris from your teeth. Brushing and flossing remain the best way to physically remove food remnants and plaque from your teeth and gums. Mouthwash then kills any remaining bacteria and freshens your mouth. | 3 |
6v1v1d | Repost | Digestion takes about six to eight hours through your stomach and small intestine. Food then enters your large intestine for further digestion. What happens when you eat something bad, and all this is reduced to minutes? | The short answer is this: when your body believes it's been poisoned, everything is suddenly on the express line out to get rid of that poison before it's metabolized. You can't really slow down digestion and just hold onto that stuff, so you have to get it out. | 11 |
c0o78n | Other | what the proposed extradition bill means for Hong Kong and mainland Chinese citizens (please and thank you) | China and Hong Kong is under a one country, two systems type of structure where Hong Kong could do it's own thing and China wouldnt interfere, which also included criminal prosecutions. Under this proposed bill criminals in Hong Kong can be extradited to China and prosecuted under Chinas laws, which effectively shatters the one country, two systems format. It means nothing for Chinese residents but have huge implications for Hong Kong residents as HKers are now potentially subject to the more restrictive Chinese laws and criminal proceedings. | 1 |
76ht8f | Other | Why does there seem to be a global rise in Xenophobia? Or has it been there all along and people are just more vocal now/have more visibility due to the internet. | If you mean the rise of identity politics and nationalist ideology, my thought is that there's a perception that there's just not enough to go around. Take the women in STEM thing. If you believe that there are a finite number of STEM jobs, then every woman who gets one means a man doesn't, and the same is true of immigrants. The civil rights movement reached the highest point in 1968, which not coincidentally was *also* a point of high prosperity in the US. Things like affirmative action were accepted back then because it was not going to hurt anyone to do that. There were plenty of well-paying jobs available, even with just a high school diploma. This is no longer true. In 2017, if you want a livable wage, you need a skilled position, you need post high school education, most likely college, and you probably need at least a 3.0 and a few internships. Even then, you might not make it. So when a white man hears about women/minorities being recruited to STEM (one of the few good jobs left) he might not admit it, but it scares him. He knows there aren't enough good jobs, and if Judy gets one he might not. And it's not like he can simply go do something else, everything else either pays little or requires more (expensive) schooling. The same thing happens in the immigration debate. If there aren't enough jobs period, then it's hard to convince a poor guy that immigrants are a good thing -- they might mean he or his kids can't find jobs. | 3 |
n9uxmq | Biology | why do kids hate vegetables? is it because their taste buds are still developing? I read awhile ago it was because their taste buds found vegetables like broccoli more bitter than adults, so the negative taste aspects were amplified. As the grew up their tastes changed and the no longer disliked the taste? | My mom used to say that the reason I didn't like my Aunt's veggies was because she thought that little kids should have raw and untouched products with the "nature" intact. My mother then simply washed, blanched/flash steamed and lightly seasoned with a salt-red pepper-garlic-onion blend. It was absolutely amazing! I TOTALLY fucking love vegetables because I've learned how to cook them correctly, thanks to my mother. | 2 |
66ii00 | Biology | why do people sometimes throw up during intense exercise? | Your Nervous system has a branch called the Autonomic Nervous System that controls a bunch of autonomic processes like blood pressure, secretions, etc. The ANS has two branches, the sympathetic nervous system and the parasympathetic nervous system. These are your "fight or flight" and "rest and digest" (respectively) nervous systems. Your body runs as a balance of these two nervous systems and the balance is shifted depending on the scenario (like being chased by a bear) So normally, your PNS, rest and digest, is in charge, and one of the things it controls is the digestive system. Digesting requires a lot of blood to circulate to the area and requires a lot of energy (ironically). This is something that happes while you "rest and digest." When you exercise your body treats it like you're being chased by a tiger, hence activating the Sympathetic nervous system (SNS). When you're being chased by a tiger, you dont need to be spending energy digesting the burger you just ate but instead pumping those legs and thinking really hard to run away and deal with the situation. So, the SNS will override the PNS and contract certain blood vessels in the gut, stop the movements in the gut to push and churn the food (also called peristalsis), and break down fat, to spend its efforts on running away. However, the controls of the digestive system keep certain parts in their specific spaces (stomach contents in the stomach, etc). By the SNS overriding the gut control, the stomach cant contain its material. As a result, you end up letting it all out and barf. Its also why some people shit their pants. Some dont have this happen to them because the signals arent as strong in the gut, they can hold it down willingly, etc. Source: TBH i dont have one but I'm a student in pharmacy school and this actually came up in our ANS lecture. | 8 |
eactas | Biology | Why does the sound of babies & toddlers crying or whining trigger such anger and annoyance in certain people? What is it in their brain that responds to the high pitched sounds that way? | I’ll be honest too and say that that septic noise also annoys me. Does it change if they are your own kids ???? | 6 |
aqlkso | Biology | Why does water taste “sweet” sometimes? | It could be any number of things. It could be a subconcious thing, something sweet (like lead) could be dissolved in the water, or it could contain a large amount of heavy water , which is supposedly sweet tasting. URL_0 EDIT: link wasn't working for some reason so added plaintext link | 1 |
ewrsjt | Engineering | What's the difference between a pipe and a tube? They seem the same. | Very little. The term tube is usually used for something with a bit more flex, whereas a pipe is most often rigid. A tube and a pipe perform more or less the same function, but pipe vs tube is primarily dependent on where you’re building something or what materials you need to move through it. | 4 |
8vb65q | Chemistry | what makes bleach such a powerful pigment remover? | Bleach destroys molecular bonds. Pigments (in order to function like a pigment) tend to be quite precise and complex combinations of atoms. Compare it to turning a car into nuts and bolts, except at the atomic level. This is also why bleach works on *most* stains, but not stuff like rust stains (as this is simply a combination of 2 or 5 iron/oxygen molecules depending on the state of iron) | 4 |
bm1h4g | Culture | Why can the US Military charge and convict someone of adultery like a crime? I agree cheating on your spouse is awful, but i don't understand why something like that is a punishable offense by the military. & #x200B; Please be gentle, first time posting. Edit: thanks everyone, I now understand. Makes sense to me. | David and Bathsheba. Basically, you don't want the guys in to worry that the guy sending them into battle is sleeping with their wife. | 6 |
lvi4b2 | Chemistry | Why do elements have half lives, and all of them have one? | Elements that are unstable (which are typically the larger ones, like your classic uranium, plutonium, radium, etc) have half lives. Imagine you squeezed a bunch of magnets together in a ball, and then to keep them from repelling themselves away from each other you used a bunch of rubber bands to hold that ball together. That is kind of like how the Nucleus of an atom works, the protons (like the magnets) want to repel away from each other since they're all positive charges. The protons are held together in the nucleus by the strong and weak nuclear forces (like the rubber bands). In smaller atoms, the rubber bands are able to hold this ball together pretty easily. But as the atom gets larger, with more and more protons squished in, it becomes harder and harder to hold them all together. Eventually something happens that triggers a spilt and some of the protons go flying off, forming two new byproducts of the original element. like one of the rubber bands snapping and letting some of the magnets go. The thing is, this event for each atom is totally random. We don't know exactly when the rubber band will snap. But, when we have a big group of them together, we are able to find a rough estimate of how long it will take for the rubber bands to start snapping. This estimate is the half life time. Which literally means "After X amount of time, we can expect that half of the original material has decayed" or in our analogy "after X amount of time, we can expect half of our magnet balls to have snapped rubber bands". | 3 |
6sm2a8 | Other | Why College Football schools needs that large stadiums (90k+ attendance)? Univeristies plays about 6-8 home games at home during football seasons. Some of the stadiums hosts football games from high schools or bowl ganes - but the other big ones? For 8-9 months - that large stadiums generate costs. | The supply (90,000+ capacity stadia) exists because the demand exists. Some universities lose money on their football programs, but the big name ones--Alabama, Florida, Southern Cal, Ohio State, Michigan, LSU, Georgia, Texas, Oklahoma--make tons of money. Tickets sell out years in advance, for $100 per ticket in some cases. They also make tons on media deals. Most D1 colleges also have huge student bodies--30,000 or more--which means they need to give a big section to the students at a discounted rate. So they need an extra 60,000 seats to sell to alumni and the general public to make their money. Your average college football stadium is pretty old, too. The stadium at my alma mater was built in the 1920s and has been expanded since then. They're nowhere near as nice as what you'd find for an NFL or MLB team, pretty much just concrete, stairs, and some walkways with concession stands. They're almost all outdoors--I can't think of a major blueblood or semi-blueblood team that has an indoors one, in fact. So upkeep is loads cheaper than an indoor one with HVAC systems and all that jazz. | 3 |
nlo8wr | Biology | If in most cases "death" directly implies the lack of oxygen supply to the brain then why can't we develop a technology that directly provides oxygen to the brain in worst-case scenarios to prevent any shortage at all? I'll make my question a little more clear. As far as I read, whenever a person is about to die, all that's happening is that their heart stops beating which in turn stops the brain's access to oxygen. I read that it is possible to revive a dead person within 3 minutes of heart-beat-stopping as the brain usually has a 3 minute backup oxygen supply. Why have there not been any research or investments in developing a technology like the "defibrillator" which revives the heart, but instead to keep the brain alive? Also, question part 2: why does the brain die in 3 minutes? Why can't it be revived? | We do have a technology which can provide oxygen to the brain keeping someone alive until whatever cause their heart to stop can be healed. It is called chest compressions. Whenever someones heart stop you have to apply chest compressions to keep their blood flowing providing oxygen to their brain. And continue to do this until professionals arrive and take over. When they are able to find out why the heart stopped and fix this then the heart will resume is rhythm and chest compressions are no longer needed. If you are on a movie set this is easy because you can just use a defibrillator and it somehow magically fixes any issues if it is convenient for the plot. However in real life this is not the case and the defibrillator is not used unless someone is found to be fibrillating. The brain needs oxygen because all the neurons use a lot of oxygen. Unlike muscle tissue neurons do not have their own local supply of oxygen on hand and need constant oxygen from the blood. And unlike muscle tissue and most other tissue the neurons in the brain are not redundant as the connections made by each single one may potentially be critical for a memory or a skill. So without oxygen the neurons in the brain starts to die and the brain starts to degrade. After about 3 minutes it is likely not enough remaining of the brains neurons to get it working and repair the damage. | 6 |
94veki | Technology | Why can the sound volume of commercials on internet TV be double the actual show's volume? | The commercials are allowed to be as loud as the shows. That means if the show has a gunshot, or an explosion, or a big dramatic music swell, then the commercial is allowed to be as loud as that. Thing is, the loudest sound in the show lasts for a few seconds at most, whereas the volume in the commercial is as high as that for the whole 30 seconds. | 3 |
hp8eu4 | Chemistry | Why does restaurant/on tap coke taste better than bottled coke Or to the same effect. Why does draught beer taste better than bottled beer even if they're the same beer | My dad used to go to restaurants all across the country and refill the syrup and such for coke machines. In addition to what other people have said, I believe different chains also have different ratios of syrup to water that causes the phenomena you're talking about. I think McDonald's has a really specific ratio that isn't quite the same as other places, for example. This was all like twenty years ago, though, so no idea if this is still the case. | 5 |
a33zco | Biology | Brain's "inner music player"? | Music is a very complex subject in the brain. The auditory system is definitely involved, but the various parts of music are a bit harder to place in the brain. Rhythm, pitch, and tone are all generally processed differently from one another, and there are indications that memory and some amount of motor control is also involved. It is known that in your auditory cortex, there are certain groupings of neurons that light up in response to a certain pitch. This is an easier aspect to observe precisely, since we can divide the cochlea of the ear and see that it has a kind of gradient quality to it that picks up a certain frequency of sound, and then (through a long pathway of nerves) can end up stimulating specific cells in the auditory cortex. Tonality and timing are a LOT more difficult to idealize in the brain with our current understanding. We don't really know *how* exactly the brain can come up with melodies and tunes *de novo*, though we think that there is some natural predisposition for this. It's pretty apparent that advanced musical training has a huge effect on your ability to think musically as well. How exactly that works is a bit of a mystery, other than guesses that the brain of a musician has simply changed to suit their field of work. We do somewhat understand how a person can replay a tune they've heard in their head/recall how to play a song through memory. Memory can be divided into many categories, two of them being declarative vs procedural. Declarative memory contains information that is accessed using conscious recall - you have to *actively* remember how a song goes to listen to it in your head. Procedural memory contains information related to a task that may not require active recall, but can be preserved through doing a task. For example, if you've ever played a piece on an instrument and tried to replay it years later, you might find that you can still play a remarkable amount of the song, even if you forget the tune in a few places. That's because how you *play* is preserved through your procedural memory, whereas how it *sounds* is usually declarative. Basically, we have a very broad understanding of some of the effects music has on your brain, and can try to make some educated guesses on some ways your brain makes music, but it's still a very challenging subject in many ways. | 3 |
g0385t | Other | The Human Capital Theory. | Human Capital is a fancy way for economists to talk about the productivity of people. For a long time in economics, people thought about productivity as coming from a combination of capital and labor. Capital is stuff like machines, buildings, and recipes. The idea is that you bring people in to operate those machines, and the two together can make stuff. Capital provides a natural way to think about *quality*. A simple hand loom and a massive industrial loom are both capital, but one is much more productive than the other. A business that buys the first one has invested in less capital than a business that buys the second. Economists understood that quality mattered to labor too - different workers earn different wages, sometimes for doing the exact same job, but it's harder to compare two people in the same way you would compare two looms. Human Capital Theory begins that process by acting as if people are walking around with metaphorical machines in their bodies/minds. The more your machine can produce, the more human capital you have. So for example, when it comes to writing books, you or I are probably a hand loom. Stephen King is an industrial loom. One of the biggest (and most obvious) findings of human capital theory is that education and training matter. It's not just that especially privileged and/or productive people spend a lot of time in school. Going to school can actually make you a more productive person. This carries over into studies of the economic lifecycle. Human Capital can explain why people spend their early years learning (building Human Capital), their middle years working (applying Human Capital), and their later years retired (depreciating Human Capital). Human Capital Theory also has a lot to say about how employers and employees match, and when/why those matches are dissolved. People are learning about their jobs and building skills while they're employed, so leaving for an unknown opportunity can be daunting. | 1 |
jxijtd | Biology | Why does driving exhaust you so much? You’re sitting, barely moving any muscles in a comfortable air conditioned rectangle. Thinking about exercising for 3+ hours versus driving for 3+ hours. I’d have more energy it seems after the exercising. Driving makes me tired. | Part of it is mental. Driving typically takes a lot of constant concentration and small adjustment. You're also more or less sitting immobile for that whole time, so your body gets stiff. After a few hours of that, stiffness plus mental exhaustion feels pretty similar to physical exhaustion. | 5 |
ff95ax | Technology | In terms of cyber security, what are the differences between Mac and PC? My fiance has been watching the Jim Browning YouTube videos regarding the scammers overseas who use call centers. We were also watching ScammerRevolts who usually gets access to the scammers computers and deletes their files or syskeys them. It's been noted in both of the channels that some call centers use Macs and some use PC/Laptops. Is one more protected than the other? | A few people mentioned more market share for PC's = bigger target.. while possibly part of the reason, another very real reason is the amount of commercial products for remote admin of the windows platform, and the number of commercial malware kits. But yes, if you install something on your computer for someone else, you don't own it any more. Your fault end of story, doesn't matter what Operating System (os) it runs. | 5 |
83iweq | Chemistry | Why do chemical reactions produce energy? I understand energy as the potential for something to move by a force. So heat is molecules move and so on. but I don't quite understand why chemical reactions produce energy specifically. I find the same explanation being "bonds break" but what about the bonds breaking causes energy(or I should say work) to be produce is it the electron movement or something like in radiation? The closest answer I've found so far on the subreddit is that it has something to o with the electromagnetic force but does that mean when bonds break the atoms "scurry" away from each other? | There is a huge misconception about the nature of energy from chemical reactions. Breaking bonds REQUIRES energy, think about breaking apart anything, energy is typically involved. Forming bonds RELEASES energy. The reason energy is released is based on thermodynamics. Basically, equilibrium favors low energy. When a system goes from a high energy state to a low energy state, energy is released in some other form as heat or motion etc. but always conserved throughout the universe. | 1 |
9h59id | Other | . Michael Foucault Like wtf. Even attempted explanations of ideas quickly devolve into what appear to be philosophical masturbation. What are the basic tenets of his ideas? | In a nutshell: When we think of "power," we usually think of "sovereign power," the authority of a legal overseeing force that can declare from above. But the form of power that most affects us is a kind of networked, decentralized power that we all participate in even as we are subject to it. This power generally takes the form of "knowledge" - we claim to come to an understanding of something (medicine, insanity, sexuality, etc.) but what we actually do is redefine the terms by which we're able to think about it. We bring new social realities into being under the guise of having learned objective truths. & #x200B; That's kind of basically the core of it that most of his books assume. Part of the problem with Foucault is that his books assume it rather than outlining it, for the most part. If you want accessible, readable and understandable Foucault, don't bother with the books he published in his lifetime (or at least, save them for later) and read the College de France lectures that were published after his death. They're a LOT less cryptic. | 1 |
6bmyjd | Biology | Why does cold water taste better than warm water | Fun fact: Room temperature water hydrates you more efficiently than cold water despite not tasting as refreshing. Your body has to heat up the cold water to your body's temperature to process it, so it wastes more energy. | 2 |
lonmiw | Biology | Why does stuff not decompose in formaldehyde?? | decomposition is a product of bacteria eating away at our dead flesh. introduce a chemical (or environment, like everest or swamps) that kills any bacteria, and you have a preserved body, as long as there's no moisture in it. | 3 |
g8178y | Mathematics | What is grahams number and how big is it. | Short answer is, however big a number you could possibly imagine, it's bigger. Seriously. It's not even useful to say that some enormous figure like the number of atoms in the universe "doesn't come close", because that suggests that maybe something else does come close. Nothing does. Nothing we can imagine even vaguely takes you near the scale of Graham's number. Even those kinds of stories you can invent, where something takes an unbelievably long time, and then you stack them together. For example: - every 1000 years, a man takes a teaspoon of water out of the ocean. - when all the earth's oceans are depleted, a sheet of paper is placed on the ground and the oceans are refilled. the process continues until another sheet is added to the stack. - when the stack of paper reaches the sun, I take a single atom from Jupiter, and the stack begins anew. - when Jupiter is all gone, I do something else - etc, etc, It still doesn't matter. What I choose for each step, how many steps I string together, it just doesn't make a difference. The time, in years or in nanoseconds, is still incomprehensibly far away from Graham's number. So now that we've established it's a hopelessly futile endeavor, it is a real and specific number that was used in a legitimate mathematical proof. So it can be understood in some way. I'll leave that to other commenters since I don't know the details of the problem it solves. But what I can help with is how it's written down, and just how quickly trying to get there working up from regular numbers blows up. To discuss Graham's number we will use a notation commonly called the "up-arrow", but I don't know how to write that in reddit so it hardly matters. The important point is that it sort of extends the relationship between addition, multiplication, and exponentiation. To multiply a number by some other number *n*, you add the first number to itself *n* times. For example 4x5 = 4+4+4+4+4. This we're all familiar with. Similarly, to exponentiate we multiply some number of times in a row. For example 4^5 = 4x4x4x4x4. This grows a LOT faster than multiplication. So the up-arrow concept extends this further. If we call exponentiation "order 0", then the "order 1" operation would be to exponentiate a number of times in a row. 3 (order 1) 3 is the example i'll use. This would be 3^(3^3) -- evaluating from the top down, that becomes 3^27 which is something like 7.6 trillion. This blows up even more quickly than exponentiation, of course. Now to order 2. That would be 3 (order 1) (3 (order 1) 3). We already know the top part, so we have 3 (order 1) 7.6 trillion. And this is where things go from big, to impossible. 3^(3^3) already blew up fast. Adding another 3, we'd have 3 to the power of 7.6 trillion. This is a number with trillions of digits. Just storing it would take a modern hard drive in full, let alone computing it. But still, it's at least *imaginable*, in some sense. Add another 3. We're up to 3 (order 1) 5 now, and pretty much out of luck. Just stating the number of digits this number has requires an understanding of the actual scale of 3 (order 1) 4, which was already a big reach. Writing down 3 (order 1) 5 is not physically possible in the observable universe. Just expressing the number of digits it has is a significant endeavor. Back to order 2, in case you forgot where we were. We wanted 3 (order 1) 7.6 trillion, and the limits of our comprehension fell vastly short by the time we got to 5. It's impossible to overstate how fast this number blows up as we try to get to 7.6 trillion. At this point all we can do is talk about it. To start talking about Graham's number, we need order 3. Specifically, 3 (order 3) 3 just like the previous examples. I'm not even going to try and imagine this one, just suffice to say it's out of reach. Everything I said at the beginning about Graham's number is true of this number too. Hell, it was true of order 2. 3 (order 3) 3 is called G_1, and we define the set G recursively: G_(n+1) = 3 (order G_n) 3 Somewhat beautifully, this means we can think of G_0 as 3 itself. To recap, G_0 = 3, and G_1 is already immeasurably far from comprehension. To try and compute it, you're very quickly doomed because the order 1 operation blows up immeasurably faster than exponents, and the order 2 immeasurably faster than that, and so on. The G set itself uses the previous value as the *order* of the operation to generate each next value. G_2 involves an order G_1 calculation. We're not even well equipped to talk about how fast this G set blows up. And we couldn't get off the ground with computing G_1. Graham's number is G_64. | 4 |
71kmdu | Chemistry | What advantages do jet fuel (particularly "Jet A") offer over auto fuel like unleaded, diesel, etc? | Jet fuel has higher energy density than gasoline. It also is less easy to ignite than gasoline. This poor ignitability is not a problem when the fuel is used in turbines, and gives a considerable safety advantage over gasoline, especially in military planes. Finally, jet fuel is cheaper as it is largely kerosene based and kerosene makes up a rather large fraction of crude oil. When you measure your fuel load in tons a few cents per liter makes a difference. | 3 |
aaec0x | Biology | How does radiation work in killing you? Okay, so, what is the element actually doing that causes it to be deadly? Like, what is it spewing off that causes such horrible effects like cancer and practically decaying? And how does something stay radioactive, like if you picked something up from, I don’t know, Chernobyl, what’s going on to make it dangerous? | Ionizing radiation like UV, Xrays, and Gamma rays are powerful enough that when they hit DNA they cause it to split apart where they hit. If this only happens once or twice then your cell can put everything back together but if the DNA gets blasted into a hundred different pieces then odds are your cell isn't going to put it back together perfectly. If your cell realizes something isn't right it may self destruct or if it doesn't then when it splits those two copies may be unable to properly build proteins and then they die. You're constantly being exposed to low levels of ionizing radiation but your cells can put that damage back together. The dangers of something like the Elephant Foot in Chernobyl is that it will hit you with millions of times the normal background radiation level and will cause so many cells to malfunction in a window of time that its impossible for your body to repair the damage so organs start failing and systems shut down until you die. | 2 |
5rw7yt | Technology | How do electronic pH sensors work? This is pretty much what I wonder about every kind of sensor - electronic scales, cameras, etc. - but the one I especially don't get is an electronic pH probe. What exactly is it that "senses" the H+ ions present in a solution, differentiates from any other kind of dissolved cation, and translates the intensity of the "H+ signal", whatever that is, into an electric signal picked up by a computer of some sort? And how does it detect the total volume of the solution that the pH probe is submerged in, in order to calculate the H+ concentration that is prerequisite to calculate the pH? | An electric pH meter is essentially just a voltmeter. An acid solution is essentially half of a battery, so the pH meter brings the rest of the battery along and measures the potential difference between the two leads on the probe. Once you've determined the voltage of your "battery" the Nernst equation gives you the relationship between voltage and hydrogen ion concentration. Volume is irrelevant to figuring the pH out in this way because volume does not affect voltage of a battery, just the life of the battery. | 1 |
ghqr6b | Other | Why and how are corporations "people"? | Corporations exist to provide a legal entity to protect people from the risks associated with running a business or group, and to streamline the decisionmaking process. For example, if you have a business run with shared property, you effectively need the permission of every single person in that business in order to do something like sign or negotiate a contract or whatever. Instead, the law allows you to create a legal entity separate from the people who own/run the business to serve as a surrogate person for these kinds of situations, thus that surrogate person is afforded some of the rights that normally would only be afforded to people. The debate over corporate personhood is mainly just the legal debate over how many and what kind of rights are given over to corporations. However, the core concept is extremely old, particularly in legal systems that descend from the Common Law system of the British Empire. The sticking point these days is corporate speech, and whether or not that right is/should be afforded to corporations. | 2 |
gi24qa | Biology | What's the line between superstition and delusion? | A delusion is something that fundamentally defies reason. It is similar to a hallucination. Someone who is delusional will believe something to be true, no matter how much it conflicts with observed reality, and no matter how much evidence they're offered to prove it's false. A superstition is much milder. It typically has a smaller impact on the person's life, and it's much more prone to being disproven, although it's usually harmless enough that nobody bothers proving it incorrect. Examples of delusions are things like delusions of grandeur - truly believing you have some kind of special power or are related to important people. Or delusions of persecution - truly believing that someone is out to get you in particular, like an imaginary nemesis. Or somatic delusions - truly believing that you are physically disabled. For diagnostic purposes, delusions generally must have a notable negative impact on a person. Also for what it's worth since I'm pretty sure this is where this question comes from: belief in a god is not a delusion because it cannot actually be un-proven. Belief in things like the 7 day creation however is, as it can and indeed has been proven false. | 1 |
dm1xmv | Mathematics | Is PI proven to be a "mathematically random" number? | The fact that *some* irrational numbers are "random" does not mean that *all* irrational numbers are "random." In particular, Pi is an extremely special number that has connections to a lot of different mathematical concepts. It is a very not-random number. It is different from most irrational numbers, and is not a good example of an irrational number. Trying to use Pi to guide your understanding of irrational numbers will sometimes lead to problems. Now, let's explore "random." You actually are using it correctly, albeit loosely, according to one definition that's somewhat niche. The idea of random-ness that most closely matches what you're trying to understand is Information-Theoretic Randomness. The idea is that if, say, a sequence of digits has pattern or structure, then it's possible to represent that sequence concisely by describing the pattern. But if the sequence is "random," that means that it's unpredictable, so there is no representation of that sequence more compact than the sequence itself. The background theory for Information-Theoretic Randomness is something called Kolmogorov Complexity, which defines the information content of a sequence as the size of the shortest computer program that produces it. Kolmogorov Complexity is used for more things than just randomness, but it's perhaps simpler to understand so if you want to dig into the topic I would start there. Despite sounding really fiddly (e.g. in which programming language?) it's a pretty robust and sound topic (e.g. the language doesn't matter! Languages by at-most an additive constant, which is the size of the interpreter). Using this concept, we can say a "random" sequence of digits is one where the Kolmogorov complexity is the same size as the sequence itself. Extending this idea to *infinite* sequences of digits like the expansion of an irrational number is non-trivial, but I'm going to gloss over it. For the task at hand, the main distinction is finite vs infinite. Does the decimal expansion of an irrational number have an infinite amount of information or not? (I assume the issue with simulations is dealing with infinite amounts of memory.) This basically amounts to asking: can I write a finite program or algorithm that will print all the digits in order if we wait long enough? For Pi, the answer is absolutely, definitely yes. We have dozens of them. Hundreds. Some of them are very short. There are actually formulas to calculate the *n*th digit of Pi without calculating any values in-between. Some formulas can do this in different bases. This is *not* true for irrational numbers in general. This is true due to a simple counting argument. There amount of irrational numbers is uncountably infinite (due to Cantor's diagonalization argument). The number of finite computer programs up to some length N is finite. The number of finite computer programs with unbounded length is countably-infinite. So, there are more numbers than there are computer programs that can produce numbers. Ergo, some numbers don't have computer programs that can write them. In fact, most don't. That's what happens when things are uncountably infinite. When people ask about random-ness and Pi, there's a separate concept that tends to come up called Normality. An irrational number is Normal if the distribution of digits in its decimal expansion is uniform. Most irrational numbers are normal, by a similar counting argument as above with random-ness. It is still an open question whether Pi is normal or not. But I don't think that's relevant to the concept underlying the question you're asking. | 2 |
edf3sn | Engineering | Why don’t electric cars (like Teslas) all have solar panels built in to the roof that could add to the battery’s charge all day? Is it just cost prohibitive for the panels themselves? Would the surface area of such small panels not contribute enough power throughout the day to justify them? | A rough rule of thumb: while it's driving, an electric car uses about as much electricity as you'd get from a tennis court covered with solar panels. | 15 |