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5mbck2 | Culture | Why did early traders sail around the southern horn of Africa, when traveling to China and India, rather than make the *very* short land trip through what is now the Suez Canal? Edit: Thanks for the insight everybody. I guess I wasn't considering the fundamental math/physics behind shipping and travel. The cost (money and energy, as in joules) of travelling across 120 miles / 200 km is so much greater than sailing that it's cheaper to sail the thousands of miles around Africa. In particular, the amount of cargo being transported made the land route even more ineffective. | On a boat, you can have thousands of pounds of goods and don't need anyone to carry it. It's floating. Your crew can sleep while you continue moving. You don't need to brave the incredibly brutal terrain of Egypt. You don't need to feed and care for the hundreds of animals that may be needed to carry your cargo holds. And also - what do you do with your boat? YOU NEED THAT when you get to the other side, and it's how they got there in the first place. It's not like they could dismantle it and bring it along across the desert. | 4 |
6co5wn | Culture | What makes a great conductor great? and conversely what sets them apart from a random high school band teacher? | It's important to keep in mind that a conductor is nearly always the leader of the orchestra, too. So for weeks and months before you see him/her waving a baton around, they were in charge of auditioning band members, selecting the music, organizing rehearsals, making artistic changes or interpretations to the piece as it goes, and directing each section and musician. So there was a hell of a lot of behind-the-scenes work that we don't always think of. As far as actual performance, a good conductor is giving a dozen instructions at once. Speed, volume, and style are all communicated by single movements. Are his beats large, waving motions, full of drama? I'll bet there'll be horns blaring long, sonorous notes. Are they short, tight, precise movements, close to his chest? You're almost definitely going to be hearing soft, short staccato notes. Is he facing the trombones, pushing one hand down while conducting with his other hand? He's asking them to play softer - maybe the acoustics in this room aren't what they're used to, and they're overpowering the rest of the band more than expected. There are a million little adjustments that will go on in any given performance, and a good conductor can make them on the fly in very clear ways. And of course, all of that body language goes to the audience too. When you see that person swinging their arms in big, wide arcs, you'll get excited, even as the music begins to swell. And when you see them sweep their arms in, you'll lean in, straining to hear the soft parts of the music. The conductor is a visual cue to you to tell you what your ears can expect. | 9 |
fe2bim | Biology | If whispering doesn’t use your vocal cords, then how can you still hear someone’s unique voice/tone/pitch while they’re whispering? I’ve lost my voice from having a cold, but heard myself whispering and it still sounded like my own voice. It made me wonder how that is possible if you don’t use your vocal cords when whispering. | You got several sound boxes in your head, all with their own properties. These interact with reverberations differently then each other and other people's sound boxes. Albeit the muscles impact the sound of the first few boxes, the others are not -or not as - malleable. The brain remembering and filling in is also probably a factor. Edit; intelligence agencies/police and so on actually try to use this to identify voices even if the person is trying to sound not like himself. | 3 |
i9u2g7 | Other | Why do some car windows not roll all the way down? | It could be due to the door shape, as other commenters said. It could also be a safety mechanism, particularly for cars where kids are likely to be riding in the backseat; keeping the window from going all the way down prevents kids from sticking limbs too far outside the car. | 3 |
g4pdtc | Biology | How are birds taught to carry a message from one place to another? | The bird is trained to go home. The bird messaging system only goes one way. It doesn't really know it has a message | 3 |
74kkkl | Biology | How do we get vitamins from the sun? | Vitamin D you get in food is in an inactive form. Gets eaten, circulates around blood vessels including those on your skin. The sunshine's UV rays makes it change to another form, which then goes to the liver, gets changed to another form, finally in the kidneys to the active form that works doing things like getting calcium and phosphate absorption . | 1 |
hhmyca | Other | Why does sleeping with a pillow or blanket between your legs at night feel so comfortable and relaxing? | If you sleep on your side, a firm pillow or rolled-up blanket between your knees can keep your upper leg from pulling your spine out of alignment, thereby reducing stress on your hips and lower back. Draw your legs up slightly toward your chest. | 14 |
icua0o | Other | Why does everyone like the food that their own mom made the best? | ugh now I want my grandma's London broil with homemade mashed potatoes, gravy, cranberry sauce, and veggies. :'( | 6 |
7v8vr7 | Technology | Why does a pc have to be significantly more powerful than the console it tries to emulate? | For one computer to emulate a console (another computer), it must pretend to be the console and run the game as fast as the console does. It is very complicated and time consuming to pretend to be another computer, so it requires significantly more computing power to run the game in time. Less eli5, a console is hardware (the console) running software (the game). An emulator is hardware (the computer) running software (the emulator) pretending to be hardware (the console) running software (the game). All of the pretending takes a lot of time. Bonus, some consoles, especially older ones, have hardware flaws. Some games depend on those flaws to function. So, good emulators must deliberately have those flaws. | 16 |
5rttb1 | Biology | When you're asleep, what part of the brain filters the noises you hear, determining whether to wake up or not? | ELI13: The Thalamus is the brains stimulus filter. it decides what stimuli are important enough to be processed. The humming of electricity, the feeling of your underwear against your butt, and the smell of wet dog in your house are ignored. Your thalamus has determined that these things are not dangerous and you can ignore them. A siren passing in the distance, a bomb going off, or a bright flashing light will attract your attention because it is different and considered important. When you are asleep, your thalamus works the same way but on a more lenient system. Some stimuli might wake you up but if it isnt important enough you will fall back asleep without even remembering (a light turning on in the hallway or a dog barking). Others might keep you up for hours (a door slam, gun shot or the smell of smoke). It all depends on the type of stimulation and how important your thalamus decides it is for you to be awake. | 9 |
l5gtol | Technology | Why do bank transfers take ~3-5 working days to complete? Why does it take so long? With current technology I don't understand why it takes a whole 72 hour minimum? What happens in the background? It sounds reasonable for pre-computer era but nowadays? & #x200B; EDIT: In the US, guess today I learned in other countries this is instant haha. | Transfers can be handled by two methods in the US, Automated Clearing House “ACH” or wire transfers. ACH operates in batches, 3 times a day. The sending bank gathers all the transactions and a final total of money (here’s 62 credits, 72 debits, for a total of $123,456.23) and sends it to the clearing house. The clearing house then batches things up for each bank as well and sends those transactions and final overall total to the receiving bank). Each of those batches takes time. Funds availability depends on the receiving bank’s policy. My bank gives me credit for the incoming money as soon as they get the notification from ACH. Other banks wait until the notification and the actual funds are transferred to give you credit. Wire transfers use FedWire. The money is taken out of your account immediately and send via the Federal Reserve banking network directly to the receiving bank. Because it’s not as efficient as batch processing ACH transactions, there’s a higher cost associated with the transaction. But it is nearly instantaneous. | 3 |
89pr9h | Other | The definition of “literary theory” The definition is kind of confusing for me to understand so I was wondering if you lot could explain it to me differently? Thanks! | I suppose there isnt one definition but a literary theory woukd be a way in which yoi can understand/interpret literature. For example you could read a text in a feminist or post colonial way and theyre both literary theories. Or you could theorise on what literature itself is, for example literary theorist Roland Barthes discusses the role of the author in literature. | 1 |
ii5lij | Engineering | What are the specific reasons we cant scale up a model proportionally? Eg. a small bridge design that works well but fails catastrophically when scaled up proportionally. | What others mentioned about the square-cube law is right, and is the main reason a bridge can't simply be scaled up and not collapse. I'd just like to add for a moving object, the hindrance (or aid) of drag is introduced. Weight depends on volume, while drag depends on surface area. Again, square-cube law. A larger plane would find it easier to counter drag and move forward but harder to stay aloft than a smaller one. | 3 |
n3h037 | Mathematics | If math is a such a definite subject with solid answers, how are there still unsolved math problems? How do people even come up with them? Edit: y'all have given me a lot to think about. And I mean a lot, especially as someone who has failed more than one math class lmao. I appreciate the thoughtful responses! Edit 2: damn, I'm glad my offhanded question has sparked such genuine conversation. Thought I'd touch on a sentiment I've seen a lot: tons of people were wondering how I'd come to conclusions that would bring me to ask this question. I'm sure it's not just me, but at least in my experience vis-á-vis the shitty american public education/non math major college, math ain't taught very well. It's taught more as "you have these different shaped blocks, and they each have a firmly defined meaning and part of that meaning is what they can do to the other blocks. Therefore we know everything the blocks can do, or can at least theorize it" and less "the blocks can be held and put together in infinite ways and be applied to infinite things that have yet to be fully imagined or understood and we're still coming up with new blocks every now and then". Buuut now I know that thanks to reddit! | You know how to walk right? When I tell you to move 5 steps forward and 2 to the left, you can manage. Now walk to the holy grail. You neither know the solution nor if there is one at all. | 31 |
g8a3pn | Biology | Why do some hairs only grow to a certain length? I've seen people with very long head hair but never anyone with braided armpit hair or flowing in the breeze pubes. Why? | To complete all these answers, I want to add all the air doesn't have the same utility. Body hair is one of the best things from the evolution point of view : short enough for you so you can sweat (which cool down the body hence give you more stamina and that's why humans used to chase prey for two to three day, only when it's tired you go killing it). Also body hair is long enough keep air between them and your skin, adding a second layer against cold. This is how double glazed panels works for exemple. The length of the hair is the result of a compromise between these two where on your head you don't want your brain to freeze but doesn't need to sweat here | 3 |
k3gto4 | Biology | if the four basic nucleobases decide gene outcome (ACGT), but have strict complementary base pairing (A-C & G-T), are there then four values to variate with or just two, like binary? **Correction**: A-T & C-G, not ~~A-C & G-T~~ The question arose from [here]( URL_0 ), where I compared binary code to human DNA's ACGT, then someone who knows more about IT than me made a good question. If it's not clear what I'm asking yet: in binary you can have a lot of variation with the values 1 and 0 in human DNA (if we ignore RNA and (U)racil for now) there are four values, A, C, G, T. But since they bind strictly A-C & G-T doesn't that technically leave DNA with only two factors to variate with? Like: ~~A-C, A-C, G-T, A-C~~ A-T, A-T, C-G, A-T Instead of: AGTATAC | DNA is not just the base pairs themselves, but the order of those base pairs. So there are four possible choices, not two. When DNA is copied in the cells (scientists call this replication), the two strands of the DNA pairs are separated and each strand acts as a template to create two perfect copies. The other feature to remember is that the DNA code is translated into RNA (scientists call this transcription). The RNA code is then translated into a protein (called translation) which does the business of the cells. Each group of three RNA bases is converted to a single amino acid, that then forms the protein. So in this case the code is not binary, but ternary and that dictates what the final protein product will be. | 5 |
hf5l8w | Biology | how do you test that a drug is safe for pregnant women? Thalidomide clearly wasn't tested on pregnant women, and there were dire consequences. However I can't imagine many pregnant women would be keen on taking part in drug trials(?), so how do pharmaceutical companies go about testing this case? | There are several stages. They test drugs on animals such as rabbits and rats for 3 to four stages. The last two stages include checking both pregnant species and embryos. They then test offsprings up to two generations but can sometimes be even more generations. There are also many sides to research now into drugs meaning many drugs that are counted as “new” are actually forms of already existing drugs which have been proven not to be teratogenic. They also check isomers, enantiomers, etc with computer programs as far as I am aware. | 2 |
6gogkc | Economics | is there a fixed amount of total money in the world or is it changing (if so then how does that even work)? | URL_0 This Video from Vsauce explains the answer to your question very well! | 2 |
6bag6w | Repost | why competition like Chess, which does not include physical disadvantages to women still needs to seperate men and women in different competitions? | The all-women tournaments and rankings are meant as marketing. The idea is that there are many fewer women who play chess, and so having women's only tournaments is meant to encourage women to play. Women participate in regular chess tournaments as well. It's hard to find a parallel with men's sports/competition, since there are so few fields that are female dominated in the way that things like chess have traditionally been male dominated, particularly ones that lack a physical component. | 8 |
be5od3 | Biology | How come we can enter a password for years but forget it just when thinking about what it is? | Try paying attention to how you do your signature. Guarantee you will fuck it up. You have to think about something else to get it right again. | 11 |
964o79 | Economics | How share dividends constantly pay out money? I understand how shares can be bought and sold for different prices as the market fluctuates but why do some shares pay the owner an amount of money? | When you own shares, you own a piece of the company. You are therefore entitled to a piece of the company’s profits. Your share of the profits is proportional to the share of the company you own. If you own 1% of a company’s shares, you will get 1% of its profits. Dividends are your share of the profits, paid out at regular intervals during the year (or annually). Note: Sometimes a company won’t pay out any or some of its profit in a given time period, as it chooses to invest its profit back into the business. So the share of profit you receive as a dividend is technically a share of the profit the company decides to distribute to shareholders (not necessarily a share of total profit, some of which may be reinvested into the business). | 5 |
5mjzu2 | Other | What exactly happened to make Julian Assange and Wikileaks go from loved to hated? | The truth always comes out eventually. Everything he posts damages the US or Europe. The targets of his leaks are the US and NATO. Eventually people figured out this was not just a coincidence. There is a love for the underdog who speaks truth to power in democracies. This is how democracies evolve and get stronger, more inclusive. State backed shrills who seek to weaken freedom are seen for the threat they are. | 27 |
6kzaxj | Repost | Why do drinks taste better when they're stored in glass containers? | If you store a drink in a metal or plastic container the metal and plastic will slowly dissolve into the liquid. It does not happen in any quantities as to be harmful however it may have a slight effect on the taste. Glass on the other hand is much more stable and does not dissolve into the liquid at any measurable rate. This is also why glass is very commonly used in chemistry as it does not taint the chemicals. | 1 |
bouz0m | Psychology | when someone has a mental health issue like scizephrenia, why do the voices in their head always tell them to do messed up stuff? Why doesnt the voice sometimes just like remind them to floss and stuff. | I feel like it may just seem that way cos we only ever hear about the really messed up stuff. If a voice in someone's head said "hey get some grapes next time u go shopping" it wouldn't exactly be newsworthy | 9 |
bfxz9t | Other | Why do Marvel movies (and other heavily CGI- and animation-based films) cost so much to produce? Where do the hundreds of millions of dollars go to, exactly? | Cast salaries can total 50-100 million if it is the Avengers. Scarlett Johansson and Robert Downey Jr making 20+ million (depending on box office) adds up. The lesser characters are usually taking home 2-5 Million. | 21 |
bjmm6l | Biology | What's making my heart beat? What exactly makes it beat? Where does the energy come from and what prevents it from stopping for no reasons? | Basically there are so called pacemaker cells around your heart that give the signal when to contract. Your heart is a muscle itself and muscle cells are able to contract, in this case to make your heart beat. The energy used in the contraction is the same as in the rest of your body (ATP), the pacemaker cells work like other neurons (by potential differences). Those cells will normally never stop to do what they are doing because they‘re controlled by a mix of signals from your central neuronal system, hormones and other stuff (so they can regulate the pace in which your heart is beating). | 2 |
6h60mp | Technology | Is "paperless document" more energy efficient than a paper one? I have wondered this for quite a while. Hosting documents on servers, consuming energy all the time, and more each time you send/fetch data. But if you have something on paper, it is statically there. You can put it away and it will not consume anything anymore? So which way is it? | Yes, also it's not just electricity, think of the water, land. Electricity can be renewable as well, its over 80% renewable here in New Zealand | 2 |
n4rjkv | Physics | Why in some mirrors, when there’s a stain on the mirror, you can see some “space” between the stain and its reflection, instead of them touching each other? [like this water drops]( URL_0 ) | For most mirrors, and especially regular bathroom mirrors, the reflecting surface is on the \*back\* of the glass. It's a sheet of plate glass with reflective metal on the back surface and the clear glass in front. The water is resting on the front surface of the glass. The reflection (the actual mirror surface) is on the back surface. The "gap" is the thickness of the glass in between. A mirror that's silvered on the front surface, like a big telescope mirror, won't do this. | 6 |
kxrg89 | Biology | Why are men so much more romantically desperate than women. | Because any woman whos even half decent looking just has to be there to get guys attention, where as guys have to really put in work to impress a woman. As a result, decent looking women always have men chasing them but guys who don't put in the effort or have the charisma to approach women will have none. Thats why so many men are on dating sites. | 4 |
5qw0i9 | Biology | why does the body physically hurt when emotions are strong? | Psychologist and PhD candidate in Psychosomatic Medicine here: Strong emotions can be a sign of psychological distress and for individuals with a history of emotional deprivation and traumatic experiences, pain sensitivity can be hightened in the process (see stress-induced hyperalgesia URL_0 ). In other words, if you were emotionally deprived in your upbringing, dealing with strong emotions might be difficult and one reacts the only/best way one has learned, through hightened sensations of physical pain. Invididuals who had others help them deal with strong emotions and therefore buffer stress might be able to react more adaptively. This is one explaination of this phenomenon and doesn't necessarily apply to all people feeling physical pain due to strong emotions. | 10 |
e68fgl | Biology | Why does the flu shot need to be in the arm? Is there a reason besides comfort? | It needs to be in a large-ish muscle, and your upper arm is a convenient muscle to use since it doesn't require you to de-pants. | 3 |
gn4s4j | Biology | Why we tense up when we’re in danger? I’ve heard a few times that drunk people don’t get injured as badly because of the ‘rag-doll effect’. So what’s the reason for tensing up when we’re scared? | Its your fight ot flight response kicking in. You're tensing up and your body is jumping all of its energy into your muscles to either fight or flee from what you're afraid of. | 1 |
d8no0r | Biology | What is that film on the bottom of your nail? | Is it towards the part where your nail joins your finger? That's called the cuticle (cute-ickle), and it protects your nail from bacteria while it grows, at least as far as I've been able to google. | 3 |
jk6mif | Physics | Where does wind start? | Why did you have to put this question in my head? | 17 |
jsgof5 | Biology | I’m 4 days cigarette free - I feel so much more energy and clarity! What about nicotine or tobacco made me feel so anxious, low-energy, and generally miserable? | I’m in about the same place, I quit on the 5th. Thought I would be far more miserable than I currently am. The main thing seems to be breaking the “oh, now would be a good time to smoke” habit. Just have to keep reminding myself we dont do that anymore | 14 |
aaolj7 | Physics | Why is space black? Aren't the stars emitting light? I don't understand the NASA explanation. | Stars do emit light, but there's nothing in space for the light to bounce off of. The light bulbs in your house light up the rooms because the light hits the walls and objects in the room. Space doesn't have any walls or objects. | 20 |
nl3w3a | Technology | What are drivers? Why do they need to be updated so often? Why are they even called drivers? | Drivers are an interface between the operating system and the hardware. The operating system doesn't know how to operate every piece of hardware, so it needs something in between. I guess it's analogous to different cars having the same interface (steering wheel and pedals) even though under the hood they might operate completely different (gas or electric or rotary engine etc). They are called drivers because they drive or control hardware. | 1 |
a1arl6 | Technology | Hatsune Miku | Hatsune Miku is a character from the Vocaloid series of software, which allow users to create songs with synthesized instruments and voices. Miku is one of the many "Character Voices" for this series, including other characters like Kagamine Ren and Lin and Megurine Luka, which are frequently found with her. Miku was a particularly popular add-on pack and her image was licensed by Good Smile Racing in 2008 for use on their cars - spawning Racing Miku and boosting her popularity. | 2 |
9zapf5 | Other | Why are they called "Soup & Oyster Crackers" when no one eats them with oysters? I like them in my chili or soup but I've only ever seen people eat oysters with saltines. | They are eaten with oyster stew. My parents used to make oyster stew to eat with good family friends. It was always a special occasion and oyster crackers were always a standard addition. | 1 |
7345ei | Culture | What happens if an pornographic actress stops consenting mid-shoot? Do they have to sign a contract where they say that they consent to a full "session"? | A contract doesn't matter as far as forcing her to finish. You can't compel specific performance on a personal service contract, sexual or otherwise. The fact that it's for a sex act doesn't matter, it would be the same for a magician's assistant getting sawed in half or a stage actor suspended in the air on a harness or anything else. Even if you could, that would be for a court to order and not for the director or other actor or whomever to physically force. If she doesn't want to continue, they can't force her. | 4 |
a71ufn | Technology | Nueral Networks. | I saw a TV programme years ago that showed a "machine" built out of matchboxes and coloured beads that could be taught to play tic tac toe. Turns out that it was effectively a mechanical neural network designed in the '60s named MENACE. Details here: URL_0 | 2 |
9o97wg | Technology | How is it that Google became a much more popular search engine compared to URL_0 , altavista or even yahoo when they basically do the same function? | Google got much better results. The older ones, back then, often didn't do so well and you had to try a few times with different terms to get what you wanted. It took a bit of skill to find what you wanted sometimes. I was pretty good at it and people would sometimes ask me for help in finding obscure things. Wikipedia wasn't around (or was kind of obscure) which also made things more difficult. | 8 |
7t62iz | Economics | Why is the price on small retail purchases usually fixed (groceries, etc.), but on large retail purchases (cars, houses) it's negotiable? | There are lots of explanations for why we don't haggle over small purchases, but no explanations for why we *do* negotiate the price of large purchases. The answer is that the seller would like to sell every item for exactly the most amount of money that the buyer will pay, while the buyer would like to purchase the item for exactly the least amount of money that a seller will let it go for. For example, I sell widgets. When you come into my shop, I offer you a widget for $800 and you buy it. That's good, but you actually would have paid $1000 if I had offered that price. I just left $200 on the table. That's bad. On the other hand, you come to my widget shop. I offer you a widget for $800 and you buy it. That's good, you're happy with your new widget. But I would have been willing to sell the widget for $600 if that's all the money you had in your pocket. You overpaid by $200. That's bad. A negotiation is the seller's attempt to discover the highest price the buyer will pay, and the buyer's attempt to discover the lowest price that the seller will sell for. Usually, you meet somewhere in the middle. For large purchases like cars and houses, the thousands of dollars that each party might gain or lose makes a negotiation - even if it takes an afternoon or multiple days - a sensible practice. For small purchases like groceries, the one dollar that you could possibly save on a steak by haggling for five minutes just isn't worth the time of either party. | 36 |
70cnzu | Engineering | Why are roundabouts so uncommon in the US even though research claims that they are safer and more efficient? Could there be some particular reasoning to this like, is it something that isn't taught much in civil engineering schools or do American city planners just not give them much thought? They are much more prevalent in other countries and after having used some I've seen first hand how much better they are than the traditional 4 way intersection. Just boggles my mind. | Real estate developer here. I know we aren't excited about using them in a private development because local code requires up to 96' circumference of right-of-way for a cul-de-sac or roundabout vs 50' width (26' street and 12' of r-o-w on each side) for a street or 4-way stop. The fire department usually dictates this by the size of their largest ladder truck that may need to turn around. The economics don't compare when you're selling valuable land by the square foot. In a public project the city would have to buy more r-o-w which isn't popular. I envy how much smaller and dense everything is in Europe. We have so much more land in the states and the code takes full advantage of that. | 5 |
belhrv | Biology | When you have a head-cold, where does the seemingly never ending supply of snot come from? How does your body make it so plentiful and quickly? | Wow thanks for posting this. I was wondering this same thing the other week but never got around to asking. | 6 |
6ryknk | Biology | Why is our skin color the way it is? Why can't it normally be some random color like purple or green? | Skin cells are translucent and colorless. When you pile a lot of them together, as in skin, they look white. In albinos and very white people, the skin color you see is just the White of the cells with some pink from all the tiny blood vessels. Skin cells produce a brown pigment called melanin, which protects the cells from solar radiation. In people of different skin colors, the cells produce different amounts of melanin. All skin colors are just different amounts of melanin in the skin. No one has green or purple skin because melanin is brown. | 1 |
e34u5a | Technology | Why do some lights glow after being turned off? Sometimes when you turn a light off it glows quite dimly, but it only happens with some lights, can anyone explain why this is? | Modern lightbumbs are no generating light by heating, they use another, more efficient physical processes which will emit light that is not visible (UV light) Inside the light bulb is a powder made of a special material called non newtonien crystals, which will emit visible light if they receive UV light. This process is not instant, as the crystal will still keep glowing if the light is turned off, sometimes for several seconds, more if you have good eyes adapted to the obscurités | 2 |
8qkb0i | Biology | What's happening when wasabi clears my nasal passage? Does it depend on taste? Do people with no sense of taste still experience the same clearing effect? | It's not related to taste. The irritant in the horseradish, Allyl isothiocyanate, is causing your mucous membranes to produce more in response. This has the temporary effect of watering down what is already present, thinning it so that it is more easily cleared (And potentially making your nose run), as its wetter when it first is excreted. | 2 |
ime955 | Technology | Are end-to-end encrypted apps like WhatsApp protected against backdoor in system? I want to know if such a backdoor would enable the attacker to bypass the app encryption and see the messages. For example if a company hid a backdoor in their custom layer over Android, I am assuming every activity in that phone is compromised. | The messages are end to end encrypted, meaning that they are encrypted between the sender and the receiver, but in the sender and receiver’s phone they must be unencrypted in order to be readable, so if you get access to a phone, whether physically get it and unlock it, or with a backdoor, you can access the messages in theory | 2 |
9wc2sg | Culture | How were companies a few generations ago (1950’s and 60’s) able to hire entry level workers and train them to work there for life? | After WWII, all the industrialized countries around the world were decimated. There was no competition for American companies or workers, and there was an enormous need for American companies to help rebuild. So there was both limited supply of workers and a huge demand for them. Therefore, most American workers had very steady, high paying jobs despite having high school educations at best. Today, there is competition in the labor market from several directions. There are highly skilled workers in Europe, there are equally skilled but far cheaper workers in Asia, and there is significant automation due to computers, machines, and robots. Now, there are certain industries where there are more highly skilled workers in China than in the US so they win on both cost and quality. The nature of capitalism is that benefits the extremely rich who can afford to invest in companies, and it benefits the extremely poor, who are the most cost effective workers available. That's why the standard of living in China and India is skyrocketing and billions of people are being lifted out of poverty. It's also why the rich are becoming far richer in the US. The group that is left out are the people who are rich enough not to take the lower paying jobs, but not rich enough to invest in companies. That mostly means the average person in Europe and the US is not seeing huge leaps in wealth the way the very poor and very rich are. Because companies are less dependant on one source of workers, they are much more able to fire people (or avoid hiring them in the first place.) Furthermore, in the highly skilled tech jobs that are growing in the US, there is so much innovation that the necessary jobs keep changing. The problem with the greatest need tends to pay the most, and as soon as that one is addressed, people move on to the next one. Cost of living is important to the workers, but it's not really related to the demand. For example, if I'm buying a car for $30,000, I don't care if it costs the carmaker $25,000 to make it or $29,000. But I do care if the carmaker charges me $30,000 or 34,000. In the same way, companies, who are buying services from workers, don't care what the costs are for the worker. They only care about finding the most cost-effective employees regardless of where they are in the world. | 4 |
htderz | Biology | does plant grow better under the same amount of white light or under the same amount of red/blue light? currently doing my bio proj and am kinda stuck haha, thanks in advance :") | > does plant grow better under the same amount of white light or under the same amount of red/blue light? So if I'm understanding you right, you're asking whether 4 watts each (for example) of red, green, and blue would cause more or less growth than 6 watts each of red and blue? The 6 watts each red and blue provide greater potential for growth in most plants, as less is reflected away. It might not lead to greater growth if some other part of the conditions is causing a bottleneck, say if the plants can't get enough water (which can be a thing even with their roots hanging directly into a hydroponic reservoir). | 3 |
8hcqhl | Biology | Why do drunk people see double? | your eyes are always 'seeing double.' Under normal circumstances your brain takes that incoming information and processes it into the single image that you 'see.' If for some reason the brain is significantly impaired (brain injury, you fell and got concussed, you drank a bunch of poison so that you'll dance better, etc) your brain may struggle to do this successfully | 2 |
d5wegr | Physics | Where will energy go when the universe goes through proton decay? From my understanding proton decay will be one of the last stages of the universe that we understand, thereafter atoms will no longer exist. If energy cant be destroyed does it stay in the protons flying around or are they actually gone? | The energy would still be there, just more diffuse. It would be in the form of smaller packets of energy like muons and various neutrinos. Despite significant experimental effort, proton decay has never been observed. | 14 |
cyn2nk | Biology | How young children can learn languages so easily? | In the same way they learn everything so easily, from crawling to walking to catching to riding a bike. At that age, we are biologically wired to be able to absorb massive amounts of entirely new experiences, simulate them (which is what play is about), and then learn to understand them. It’s also pretty much 100% of a child’s activity. Nothing but learning, all the time. As we get older we experience comparatively less new things, are required to dedicate more of our time to surviving rather than learning, and don’t need to operate with such high-energy “absorb all things” behaviour. So we stop being able to do it because we no longer need to. Our biological priorities change. | 2 |
60vh1r | Biology | Where does the cocaine go? Like when you snort it, where the fuck does it go? The fuck happens to it? | It eventually gets metabolized to [Benzoylecgonine]( URL_0 ) so that it can be pissed out. | 6 |
cfc0ub | Engineering | Do trains take any special precautions when crossing roads that only have a yield sign and no arms to block the road? | It’s not up to the train to take precautions. It’s up to the car drivers to take precautions. | 2 |
8l4oiq | Physics | They say the big bang started it all. How was the stuff that started it there in the first place..? | When people say "the big bang started the universe" it's meant in the same way as saying 'the kickoff started the football game'. It's the first observable event in the universe like the kickoff is the first observable event in the game. There may have been stuff leading up to that in the same way there is stuff leading up to a game, but if you the only information you have is about what happens during plays, the kickoff is the first bit you know about. Likewise, all we can describe with physics is limited to the universe so we start with the big bang. | 4 |
6ecqn8 | Biology | Does listening to the same music track on loop can cause some kind of confusion/brain damage? Since I was young I always enjoyed listening to the same track over and over again. I'm 25 now and I still have that habit! I work as an animator so I have plenty of time to listen to music while I work. Usually I listen to the same track for a week or even more than that (if I really like it), and it's usually upbeat video game music or Japanese music (mostly anime related). My coworkers always ask me how can I do that and I don't know how to explain it. Can someone elaborate on the subject? Is there a name for such a thing? | I don't think so because I'm just like you in regards to this and I don't feel like I've had too much brain damage. Just this morning I was playing the same coffee over and over again while I was making music and my dog ran out of half and half and I had to to flush it and get new ones. But seriously, I'm not aware of any evidence that it would mess your brain up. Personally, if I like a song I'll put it on loop in the background while I work, and after a week or two I'm over it and I move on. It actually helps a lot. | 3 |
8xuug0 | Biology | why do faces get oily but no other skin like our arms and legs suffer the same greasy fate? | A couple things 1) Face skin is different than arm or leg skin. Skin doesn't have the same uniform characteristics over the whole body. 2) Usually our bodies are covered in clothing that absorbs some skin oils. Usually our faces aren't. | 2 |
fam92k | Psychology | What's triggers trypophobia? Logically, it doesn't make sense, a fear of many small holes clustered together. However, for some reason it looks absolutely terrifying. What causes this fear? | Some things are just engrained in our DNA. Cats are instinctually scared of snakes. Thats why those cucumber cat pranks always work. After countless generations of humans surviving in the wilderness, our DNA recognizes non symmetrical holes with danger. It always makes me think of wasp nests. Insects nesting is something that humans find instinctively repuslive. Another would be exotic plants that may contain poison. I think thats what causes this particular phobia. | 2 |
im3kik | Physics | Is it possible for there to be a "source code to the universe" that accurately explains and predicts all physical phenomena? | This is colloquially referred to as "the theory of everything." No such theory is currently known. It's important not to use an analogy like "source code." Source code contains directions telling a machine how to behave. Physics theories are observations about how things in the universe behave and ideas about how we thing it behaves under assumed conditions, not instructions telling them what to do. The closest theories that explain the most and have experimental evidence to support some of their wilder consequences are General Relativity and Quantum Mechanics, which you can think of as the theory of Really Big and theory of Really Small. Neither is sufficient to explain the universe in its entirety. It's certainly possible the theory exists. It's also possible it exists but can't be proven, or even possible that it can't be proven to exist (or not exist). It all depends on how you state the problem. My personal suspicion is that the theory of everything is deeply tied to Gödel's incompleteness theorems which have more to do with the philosophy of mathematics than physics. We can prove that no system of mathematics is sufficient to prove all things expressed within that system. By virtue of the fact any theory of everything is expressed within a system of mathematics, it's possible no such system exists that can express the theory of everything. I also suspect that conjecture cannot be proven to be true or false. But to the specific point of *prediction* we know that isn't the case. The universe is not deterministic, and we've seen that at the quantum level. In simple terms rules of the universe as we understand them allow for multiple futures to exist, not a single one that can be predicted. Which should make sense conceptually, but it's rather interesting for that fact to be absolute at the smallest scales like predicting the motion of an electron (which is impossible). | 3 |
7ughpk | Other | Why does if take so long for a movie to release on DVD/Blu-ray after it stops showing in theaters? | Because if the movie came out immediately, then no one would see it in theaters and movie theaters won’t bother to show a movie no one is going to see. | 4 |
5ru66l | Culture | Please explain to me the Bowling Green Massacre. | Here's [a good round-up of the facts]( URL_0 ). In short: some al Quaida supporters were found and arrested in Bowling Green, Kentucky. No deaths occurred in the event, although the event caused President Obama to review immigration policies. But, no, there was no massacre in Bowling Green. | 3 |
e5spg6 | Engineering | How do torpedoes work? If I fired a rocket launcher underwater it wouldn’t go very far due to, well, water. But a torpedo sails through water. How do torpedoes work, and why do they work but above ground rocket launchers underwater don’t? | Rocket launchers are designed to work in air so they use a high thrust rocket to move at extremely high speeds through the air. Torpedoes are designed to work in water which has a lot more resistance than air. They have a propeller on the back driven by a gas producing reaction in the torpedo that provides a constant thrust. They're also rounded on the end to make them more streamlined in the water(aerodynamic and hydrodynamic shapes are different due to water being thicker) There are torpedoes that are driven by a rocket engine, they generally use a creatively shaped nose to create a pocket of steam around the torpedo. This means that only the tip is pushing through the water so there is wayyy less drag which lets these torpedoes reach 300-500 kilometers per hour vs < 150 kph for standard torpedoes | 3 |
jfaudc | Biology | How it can be written in the DNA of animals and plants the need to reproduce and preserve the species? Edit: Well, it's true this could be hard to understand to a 5 y/o, so maybe ELI15, with a basic knowledge of genetics and biology | It's not necessarily written in your DNA that you feel a need to reproduce. But your DNA makes you, and for you, sex feels good. Therefore, you'll try and have lots of sex ans reproduce. DNA that does not somehow 'contain' this need to reproduce, well, won't. DNA that does have it will propagate. In other words, it is not that the NEED to reproduce is written in our DNA. It's that DNA which tells it's owner to reproduced is more likely to be passed down and preserve the species. It's a god damned miracle pandas still exist. | 3 |
9a6vfx | Economics | difference between NY Stock Exchange and Nasdaq? | There seems to already be some good answers here, but if you need more and have Netflix, there’s a series called ‘Explained,’ and the stock market episode (which is only like 15 minutes long, so it’s not a huge commitment) is easy to follow, goes into this, and may be helpful if you’re a more visual learner! | 3 |
71piz0 | Other | how do the likes of ALDI get away with clearly copying branded products labelling? You go to Aldi and the washing powder looks just like a leading brand. The cakes look like mr kiplings etc etc it's clearly meant to be misleading but they don't stop it? | Most "generic" products are produced in the same plants that make "name brand" products. They are the same product, owned by the same companies, just branded differently. | 4 |
dd2fw6 | Physics | the suns strange gravity | With gravity, proximity is key. The Sun's hold on Neptune is actually pretty weak. Its hold on Earth is strong, but due to proximity, Earth's hold on its atmosphere is stronger than the Sun's hold on its atmosphere. | 2 |
8hsjtv | Technology | How does Google Maps know about current traffic congestions and jams? | Two ways. It can source public data feeds put out my muni authorities, state government etc, where they exist. And, now that everyone has a smartphone, they can read the location speed and acceleration from thousands of cellphones at once. If they see that five hundred Android phones on Highway X just slowed from 100km/h to 40, that's gonna be a jam. | 2 |
78ppdo | Engineering | How does a database handle 1 billion users? I'm really interested in how companies store such HUGE amounts of data but somehow retrieve and display the information in < 1s. I was looking at my Facebook activity for 2010 and it has the thousands upon thousands of posts I liked. You can't possibly store this in some sort of pivot table database, could you? Facebook would have literally 800 billion rows. And my actual question is, how does a company, like Facebook, store more than 1 billion credentials? Is it split into regions like Users_GB, Users_US? I work as a web developer. But as I work for a small company, I just can't fathom data this big. Any insider knowledge, anecdotes and discussion from anyone who works on large databases would be appreciated. Edit: Went to bed, woke up and the blew up. Thanks for all the great discussion, and thanks for the gold. | My area of interest also. They have new types of databases that do not store data in row format(NoSQL) this removes the performance constraints on storing such data in a relational database. They also do not use one database but what you get is api's pulling data from many sources e.g there could be a Ugandan facebook user db only. Facebook is the creator of new frameworks such as presto which enable speedy access to data. | 17 |
d1e74d | Other | what happens to insects after getting off our cars finding themselves kilometers far from their nest? | Other than bees and wasps, the vast majority of insects don't have a 'home' so it literally makes no difference for them, since they have no home to go back to. Those insects had been randomly flying around at point A, and will continue to randomly fly around at point B. What might make a difference is if the weather conditions were very different, especially when it comes to wind and cold. | 5 |
6x8t0d | Biology | If humans need such a balanced diet to stay healthy, how is it that most animals seem to get away with having a very narrow diet? Maybe I am naive in the diet of animals but it seems to me that when you think of, say an owl, we all know that owls eat mice. If humans were to eat just one food like that it seems to me that we would not get enough nutrients to live. How do animals get all their nutrition? | As always when this comes up, humans don't NEED a balanced diet, it's just better. You can survive almost indefinitely on a very narrow diet, it will just come with poorer health. Animals don't know how to optimise their diet like we do, and therefore live shorter lives in poorer health than they could. This is a large part of why housepets live longer than their feral counterparts, we have studied their dietary needs and provide them food with a broader range of nutrients than is available in the wild, so they live longer and healthier lives. One of the advantages humans have is the ability to process many types of food, so we can get nourishment no matter where we are. We don't need to have this broad spectrum of food types to live, we just have the ability when to take advantage of a wide range. | 46 |
6u3kw1 | Biology | Why does hunger feel so much stronger than thirst, despite dehydration coming about quicker. For example if I don't eat for a day I feel like I'm on the brink of starving to death, but if I don't drink for a day(I know you some liquid from eating) I don't feel like I about to die from dehydration. | Anecdote: as a weight class athlete, the need for water is nearly insatiable during a cut. You forget the hunger in 24 hours. | 11 |
6cpk5e | Repost | true north vs magnetic north? What is the difference between true north and magnetic north?? | True north is the direction pointing straight to the point on the globe that the Earth rotates around. Magnetic north is pointing in the direction of the magnetic field. If you were to follow the needle on a compass you would not go in a completely straight line due to local variations in the magnetic field and you would end up somewhere in North Canada. Also the magnetic north pole and the magnetic south pole is not quite opposite of each other. And they are both moving around and can change quite a lot in a century. Magnetic north is used because it is very easy to find it as you can just use a simple magnetic compass but true north is used when you need accurate measurements that can be used decades later. | 3 |
82dpwi | Biology | Why do pain killers help some types of pain, but not others? For example, my pain killers work for joint pain, but the paper cut I got earlier today still hurts just as much. | Your joint pain probably comes from some sort of inflammation within them. One type of pain killer, NSAIDs, block the production of a molecule (Prostaglandin H2) that is produced at inflamed sites and is important for pain signaling in inflammation. So when the production of that inflammatory molecule is blocked, you will feel less pain. When you have something like a cut there are also other types of pain involved, for example nerves that respond to mechanical force (or, y´know, being cut in half). In that case a big chunk of the pain comes from those cut nerves and not from inflammatory molecules, so an NSAID won´t help as much. In that case an opiate like morphine would perform better because they weaken many pain signals that are trying to reach the brain. By the way, please don´t use morphine to treat a paper cut. | 2 |
6d8ica | Biology | How are animals able to drink water from puddles from the road, dirty ponds, etc. etc. But if we were to do it, we'd fall terribly sick? | I used to drink water out of puddles, gutters, anywhere I found it when I got thirsty as a kid playing outside alone in the neighbourhood and the forests. I had been doing it for years and I knew what water was good and what bad from the smell and taste. Never got sick or anything (luck?). I don't know if it boosted my immune system or something, but I barely ever get sick even as an adult and I'm the only family member with no allergies. | 35 |
7w1zb6 | Technology | How does a computer determine when a syntax error has been made? | Syntax errors are found at compile time while it's trying to understand your code and make assembly. They're easier to see in a language like C that requires semicolons. Let's take the following example Int x=2; Int y; If(x==2) { y=4 Else { y=7; } There are two issues in there so the compiler will read though it and come across the line y=4 but due to the missing } and ; it reads as y=4Else{y=7 You can't store the value 4Else{y=7 in an integer variable so clearly something went wrong. The missing ; also messes with the interpretation of every line that follows so sometimes you'll miss one semicolon and get a thousand syntax errors because now nothing makes sense | 1 |
k3ppoi | Economics | If someone is homeless and doesn't have a picture ID or other forms of ID (social security card, birth certificate, etc) how would they go about getting the documentation needed to get a job, rent an apartment, or do anything to improve their status? | We experienced this. As a adult, my mother was homeless and an addict. Once she finally accepted my help, I as her daughter was able to file for a copy of her birth certificate. | 13 |
a051nj | Biology | why don’t we have replacement cartilage? Why are NSIADs (ibuprofen, etc) the mainstay of treatment followed by replacement? | Cartilage exists as a cushion between bones which means it needs to be soft and firmly attached. Anything we insert into the human body has the possibility to foster infections which means that the inserted substance needs to be non-permeable (i.e. metal pins, rods, hip replacements). We don't have anything that is soft yet non-permeable to act as a replacement SAFELY. And since they also have to be firmly attached we would need a way to glue them on to a living surface without damaging that surface. Much harder than it sounds. Soft things we successfully insert into the human body like fake breasts aren't really attached to anything. | 2 |
fpwjt5 | Biology | Is having an asymptomatic infection a sign of a healthy or unhealthy immune system? | Immune system may not be the factor here. Rather, the virus just can't do much to a particular physiology. Our physiology varies in many subtle ways and not many are understood. It's like seeds that require acidic soil falling on alkaline soil. They might germinate for awhile but soon die off without ever proliferating. | 6 |
cc02dq | Biology | How do STDs form/ where do the originate? Everything I’ve seen just talks about how they spread but where did they come from? | Some have basically always been, ancient viruses co-evolving with us for millions of years to spread through the population with minimal impact. The most efficient of these produce few symptoms and lurk undetected for years to achieve maximum transmission rates. HPV is the prime example, producing no discernible symptoms in many individuals so they can spread it and never even know. Then there's the "new" viruses. These jump species by entering your blood stream when handling infected animal products. Unlike the human-specific co-evolved viruses that try to lay low, many of these new infections haven't had time to optimize infection survival (killing your host doesn't help you spread after all) for the new host and rapidly overwhelm the immune system. HIV and Ebolavirus fall into that category. The third category is bacterial infection, which operate like any other bacterial infection except that they prefer the environment of your junk. | 4 |
fu56jv | Biology | Why do our hands sometimes just 'feel' dirty. It's almost like there's a layer of dirt on your skin that you can feel, even though nothing is visible to the eye. | Usually, throughout the day your body is making either sweat or oil or both come from your pores, even if you can't feel it. This collects dust/dirt/particles in the air. The thin layer of dirt really is there, its just so thin it's not visible. Wash your hands regularly! | 1 |
5r4zh0 | Culture | Why does is it impossible to find news that is accurate and can be trusted? I am only 20 so I am new to this whole politics thing and really being involved. It doesn't help that this election has been insane and I am trying to learn about good news sources through this. I feel overwhelmed and I just want honest news. I feel like for every piece of news there is someone somewhere proving why they are wrong. SOMEONE HELP. | It is overwhelming -- there are so many potential sources of news these days, and many of them spend time telling you that most of the others are untrustworthy and inaccurate. That doesn't help. So start small, with things you know about or that people you know and trust know about. What sources are accurate about *that* stuff? That's good to know. They seem to represent truth as you understand it. Then note what sources *they* trust. That will expand your potential news universe a bit, let you extrapolate to things you don't know about personally. But that's not enough. Seek out people that are different from you -- maybe a different race, maybe from a different part of the world, maybe of a different social class. Make friends with them, figure out which of them are smart and trustworthy, find out what sources seem accurate to *them*. How do those sources match with the ones that you've already been consuming and trusting? Critical thinking will be key. If you find someone obviously telling a lie, you should question why they did so and whether you can trust other things they say. It is plausible (but sad) for a person or a source to be trustworthy on some topics but utterly deranged on others. | 4 |
71r53m | Other | Why is it so hard for some people to eat in the morning? | > [It was a combination of fear of indigestion, religious moralization and advertising that helped push the idea of breakfast as the most important meal of the day]( URL_0 ). Basically it's not the most important meal of the day, but there was a lot of pressure from people, including Mr. Kellogg, to sell the idea that it was really important. | 2 |
7k63y4 | Biology | Why do humans have dominant hands? Do other species have dominant sides as well? | I don't believe we fully understand what makes a dominant hand the way it is, however most animals have a dominant side. Birds for example are more often dominant lefties. In fact, I have an African Grey who refuses to step up on a right hand because if this. I'm pretty sure he feels the right hand can't be stable because he himself is a lefty. | 8 |
myb8vo | Earth Science | How do waterfalls and rivers never run out of water? | They do run out of water. Where I live, most rivers are completely dry for a large part of their riverbed from mid/late Summer into Fall, because there hasn't been enough rain to replenish them. | 5 |
6h32he | Engineering | How come airlines no longer require electronics to be powered down during takeoff, even though there are many more electronic devices in operation today than there were 20 years ago? Was there ever a legitimate reason to power down electronics? If so, what changed? | Some airline companies such as Air China still forbid the use of cell phones at all phases of flight. I was used to keeping it on since I'm from Canada and we never require airplane mode, but I was approached by one of the flight attendants who sternly told me to turn my phone off even though my phone was in airplane mode and I was watching an offline video. Get with the times Air China... | 41 |
cshkbn | Technology | When Wi-Fi says: "connected, no internet" what's actually happening? | Your wifi is really just a device that both has its own network and connects to a wider network(the internet) . It's own network is called a Local Area Network(LAN) and the wider network is called a Wide Area Network(WAN). The LAN is used to communicate with devices on the same wifi such as sending a document to your printer and only exists on your wifi, the LAN literally is your wifi. The WAN is the internet. So when you get this message you are connected to the LAN and can print stuff but you are not connected to the WAN. | 2 |
bo7jgb | Biology | How do orgasms work? | Stimulation of nerve endings cause a buildup of tension, that releases all at one time at orgasm. Think of it like a sneeze | 10 |
ait184 | Biology | Why do flies and other insects have a bond to feces? | There's a lot of nutrients still in feces. Either in the form of bacteria, fungus or bits of undigested food. House flies, dung beetles or worms eat it, or feed it to their larva. For example, if you look at horse or cow poop, there's still a lot of bits of grass in it, the bacteria that was in the animal's stomach, maybe even nutrients that the animal didn't absorb before the animal pooped. For a fly, that's a lot of food in one giant pile, and a good place to lay eggs and feed it's young. | 4 |
a9f4xo | Chemistry | Why do mugs leave marks on the table, when the drink inside is not in direct contact with it? | The mug has a different temp than the table, either water will condense on the mug, like a pop can, or the heat from the mug will cause the water in the table to expand/evaporate. Very hot things can cause the varnish to lift as well. | 2 |
gefji4 | Biology | If plants use energy from the sun through their leaves, how are they just chillin in the winter just branches n roots? | Trees which shed their leaves use reserves of sugar to stay alive through the winter (incidentally this reserve is what we harvest to make maple syrup). They store the sugars in sap, which not only serves as a reserve of energy during hibernation, but works like antifreeze to keep cold temperatures from harming the tree. They lose their leaves because they have a very high surface area. That surface area causes a lot of water loss, which is hard to replenish with the soil being frozen. Evergreens have evolved needle like leaves which are much more water efficient, so they do not need to hibernate. | 4 |
6o5nsf | Culture | How come organ music (like works of Bach) has become associated with Halloween? I'm a huge Bach fan. Recently I was sorting through some music on Spotify, looking for obscure versions of some of Bachs organ works and I noticed a lot of them came from Halloween themed albums. There are "spooky" versions of Toccata in D, and Little Fugue in G-, and more. How did this come to be? I just don't see the connection between Bach and Halloween | Many of these works are written in a minor key or have sections that go through minor progressions, and that is considered "dark" vs a "bright" major key. The primary "dark" holiday is Halloween. Check Out Edvard Greig for more minor tone stuff that's really good. | 2 |
kaqhjv | Other | How did people learn other languages originaly. | People learned other languages when there was a need to communicate with other people. Reasons for this could be if you were a trader, a migrant, or diplomat. Formal teaching of foreign languages has been around for longer than you might think. The ancient romans were often taught Greek for example because it was considered to be high class. (much like Latin became through most of European history) But I guess you were wondering about how people learned foreign languages when they weren't schooled. The answer is simply by listening and by trial and error. If you were in a foreign country, you would have to adapt to the language spoken there. When you can't make yourself understood with your own language you are forced to learn and that makes your ears extra attentive to the new language. In important trading towns, where many different languages are often spoken, there can develope what's called a pidgin language. That is a language that's a hybrid of several languages, and that usually has a rather limited vocabulary. It contains only the words needed for basic communication which makes it easier to learn. In other instances when there are people speaking different languages close together, one of the languages (usually the largest, or the one which the speakers hold the most poltical power) becomes dominant, and the other people use that language as a lingua franca. That's actually the origins of the term lingua franca. During the crusades, French was often used as a common language between people of different nationalities. | 3 |
5n9ehk | Technology | Have Any Technologies Peaked? | Since almost anything could be made out of improved materials, it is hard to prove that anything has actually peaked. Even extremely boring things, like pencils or belts or socks or tables, clearly can be improved if someone invents a superior material to make them out of. | 3 |
5n5maz | Biology | How can we grow fruits and vegetables that are out of season? | You can ship them from locations with different seasons, or you can recreate the season within greenhouses. As humans we have the ability to recreate much of the features of seasons within protected areas. | 4 |
5ozynn | Economics | how do organizations (business or government) in general validate if a person's signature is real and not just a doodle? | A signature does not have to be a name or anything. It can be a doodle. The hope is that the doodle is consistent for the same person can be used to show that the person signed the document. The government/business isn't running hand writing recognition to see whose name it is. They are merely using it as proof that you signed the document in question. | 2 |
6wbi5v | Repost | Why do most men go bald, in spite of all the testosterone? I'm 25, I have a full beard, I have new hair coming out on my back and shoulders but the hair on top of my head have started falling. What's up with that? Are the rules different for that part of the body? EDIT: What the hell? Ads about hair products started showing on reddit. Ads do get smarter. | If I remember correctly, a running pattern amongst prematurely balding men is high testosterone levels. | 24 |
dpo5qw | Technology | How do controllable prosthetics work? How does the brain control something that's artificially attached? | We're capable of creating neural networks that can translate brain waves or electrical impulses in the target appendage into actionable information. In other words, we measure the brain waves/neural impulses of the person as they repeatedly think of doing an action. The neural network learns to associate those signals with whatever output we designate (i.e. think of curling your index finger - > run actuators to do exactly that). The Myo armband used the same technology to allow users to issue commands to devices using arm/hand gestures. | 2 |
i9xbn2 | Technology | why bathroom scales give an initial reading that is about 1.5kg higher than second and subsequent readings? This has happened to me consistently with 2 completely different brands of bathroom scales. I store the scales vertically when not in use. | Are you zeroing the scale every time first? Whenever you set it on the ground after storing it vertically, you're supposed to step on it for just one second until it wakes up, then step off and wait for it to show zero. Then step on and you should get a consistent, accurate reading. | 1 |