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j4l20 | Explain Quantum Entanglement to me like I'm 5. | When you flip a coin, you know that whenever you see a heads come up, the bottom of the coin is tails. Similarly, when you see a tails come up, the bottom of the coin is heads.
Similar to how you know the two sides of a coin have opposite faces showing, physicists can make two particles that have opposite properties (such as spin). We refer to these pairs of particles as "entangled" - they aren't free to take on any value they'd like to. Just like the bottom of a coin can't be tails if the top is, the spin of one particle can't be clockwise if the other particle is spinning that way too. | bd2eba22-ed19-4927-87eb-70459cb85fc8 |
11lew8 | Holographic images | Picture a row of little triangles in a big line /\ like that. As you move your eyes go from seeing the / side to seeing the \ side, which has a different picture. If measured correctly, this tricks your brain into supplying the missing "movement" between the two images. So one side is A and one is C, your mind fills in B. | a8bc1177-bbd5-4503-92da-40851fef4faf |
2i25uv | We've had photorealistic CGI in movies since the early 1990s ("Jurassic Park," etc). Why don't we have photorealistic video games yet? | Video games have to render the image in real-time, since your input determines what the next frame has to look like. A movie, by contrast, can take as long as it needs to get the image quality up to photorealistic levels, taking hours for a single frame, because they only have to render everything once. | 4155f63f-291a-4c05-97de-dccc715dc8e6 |
3xxtrw | When you feel like your heart is skipping a beat, is it really skipping a beat? | I've been tested for this, and in my case it is that one heartbeat happens sooner than it normally would, and then the next heartbeat happens when it normally would in regard to the first of the three heartbeats, leaving more space between the second and third heartbeats, giving me that fluttery feeling in my chest. | eb8cdd14-7399-4c54-966f-020f3de29b23 |
31rj9h | What is is that makes Buddhism a religion? | > Then, why is it a religion
Religions don't need to be a Judeo-Christian style monotheism. Through history most weren't.
> and why different from Taoism or other "related" philosophies/religions?
It's related. There's a lot of overlaps in ideas in the same way there's a lot of overlaps between a lot of the more commonly considered Western religions. | 4aac47a5-99b5-49b8-b124-de7b2f33993f |
2ama5a | NBA Free Agency and the Salary Cap | The NBA has a soft cap meaning that you can exceed the maximum salary under certain circumstances. If you go too far over you are penalized with a luxury tax. This page has a list of the exceptions _URL_0_ . These exceptions were created to help teams keep players year to year. A hard cap would cause more player movement, like in the NFL, and the NBA doesn't like this because there are so few players per team.
The Amnesty provision was an exception created during the last CBA. It basically allows teams to get rid of one player without it counting against their cap. This can only be used one time and most teams have already used it. | 076c3eda-0918-49e2-b88c-c55166b4426e |
2rzhpz | Does my dog hear his name like I do? | No. To him, his name is a command just like how "sit" is. But instead of asking him to sit, his name means "look at me/come to me" which ever way you use it. | 150ceb29-452a-468d-8475-0494e2c7d1cb |
2wza56 | Why are people so critical of their own work? | Because any medium is an imperfect translation of abstract thought.
I'll use books as an example, but it works for any media. Everything you know about a language paints a picture in your mind. When you read something someone has written, you can't help but see it. When someone describes a character, you picture that character. This is why it often feels weird when a movie is made about a book, and you see a character who doesn't match the one you have in your head, and it creates dissonance. Sometimes all of the magic movie parts come together and you get someone who is "perfect" for role: this is simply someone who matches up what's in your head.
When you're writing, you're playing a game of telephone. I don't care how good a writer you are, your translation is still imperfect. I can assure you that the Hamlet in my head is not the same Hamlet that was in Shakespeare's head. When you read your own work, your mind reflexively tries to create a picture based on what you're reading, but since those words are an imperfect representation of the idea that was already in your head, your new mental picture doesn't gel, and you get that same dissonance. The fact that they don't match up is frustrating, and you can't help but feel like your writing is terrible because it isn't painting the picture that you wanted. And you may be right! But even the greatest authors experience this self doubt and frustration and endless revision, sometimes as much or more as beginners.
Being a successful artist means learning to work through this process, and teaching yourself how to speak your own language, where you can learn how to translate your own thoughts into a medium or media which others can take in and appreciate. | 68a383cb-b882-4766-baa8-377ad4bfaabf |
4p4e30 | How do trains pull so many cars? What is the limit to the amount of weight they can pull? | The locomotive is large, and is pretty much all engine and fuel. Of course there's a limit, but you can increase that by adding more locomotives.
This [Wikipedia article](_URL_0_) describes the record for the longest and heaviest train ever; eight locomotives pulling a train of 682 cars. It was four and a half miles long and weighed nearly 110,000 short tons. | e097de79-489c-403b-bd43-da3f601809b9 |
th5k5 | How to Buy Groceries Properly | Bigger problem with 6 people in an apartment is keeping track of who owns what.
I suggest, at first, generally just buying what you plan to use immediately (1-2 days), with a few frozen/canned things (frozen pizza/burritos, TV dinners, canned soup/chili) that you can break into on short notice. This will prevent you from buying too much of things you don't need & having them go to waste. Things you can safely stock up on are dry staples (pasta, rice, beans), small pieces of meat (chicken breasts and "assorted pork loin chops" (they're the ugly end pieces from when they make pork chops, perfectly good meat, just funny looking) frequently go on sale & freeze well if you put them individually in ziplock bags). You might also want to consider frozen veggies.
In general, you want to refrigerate your fresh veggies & buy things frozen that you want to freeze (freezing veggies for long-term preservation isn't something you should be worrying about now). Meat, OTOH, should be frozen if you're not going to use it within a few days (unless already frozen).
As for separation, you want to leave your veggies alone until you're ready to use them. Most of you meat will be butchered for you unless you're buying whole chickens (whole chickens, OTOH, are really cheap. Roasting one or tossing it in a crock pot is *really* easy. It's one of /r/cooking's go-to recipes & good for a group), so that's not really an issue.
...and fuck ramen. Spend $15 on a rice cooker and buy a 20lb bag of rice. | b8b63ec7-c56d-4348-b079-0789de419b59 |
4jl7tk | Is there a correlation between a full moon moon and odd behavior? | My girlfriend works as a midwife and says the same thing. She hates working night shifts on a full moon, "because it is madness".
I don't believe it actually makes a difference, there is no scientific proof.
Although I'm aware that these old wives tales, and a lot of folklore regarding full moons does stem from odd behaviour at these times. | d308c673-506b-4284-b029-88c124c03185 |
25a1sd | What is corporate welfare? (no politics please) | Take major league baseball for example. For a particular team, the stadium they play in may be 50 to 100% public money. To build the stadium, local government may take away land from other private owners. The team is exempt from local and state taxes that other local businesses have to pay.
For agriculture, farmers get very cheap crop insurance from the government. Subsides to grow and not grow certain crops.
For technology and manufacturing. Some companies get low interest government back loans, free government land and no tax for a number of years.
For oil, gas, coal and mining. Companies get to take valuable minerals out of public land for a very low price, and they often leave the land in a very polluted state.
For finance companies. Government often assume the risk (if a student doesn't pay back his student loan, government pay it back), but let the financial institution earn the rewards (that 8 to 19% interest on the student loan).
For government contractors. Government overpays on services and products, it may not even need. | 4ca37ad7-9765-4887-b0a1-f806f520a6e4 |
228zt0 | Why is it that when i get 8-9 hours of sleep i wake up tired but when i get 3-4 hours i wake up energized? | When we sleep our brain goes through a cycle of activity. This cycle will vary between 80 - 120 minutes and may repeat 4 or 5 times during the night. The "deepest" part of this cycle is called REM (Rapid Eye Movement) sleep. This is the state usually associated with dreaming. We will enter REM sleep various times throughout the night, each time lasting longer than the last.
If you wake up during REM sleep, you may feel more groggy than if you woke up in an earlier stage of the sleep cycle. If you don't have a regular sleeping schedule then your body may not regulate these cycles and you might wake up in the middle of one and feel "worse". Where if you wake up after 3-4 hours of sleep you may be waking up during a more natural part of the cycle. | 4b9d28bd-f078-45ff-bf46-75345c0df17f |
2hhv63 | Why can't we put metal objects in the microwave, yet the inside is made of metal, including the metal mesh on the inside of the door. Is the metal coated with some special paint that makes it ok to be exposed to microwaves? | The electrodynamics are sort of complex. I am not saying you should try this at home, but a lot of it has to do with the shape of the object rather than the material, so you can *technically* safely microwave metal.
A microwave is a form of electromagnetic radiation, just like light. You don't really have to know what that means other than the fact that it's radiation that interacts electromagnetically (scientists are good at naming stuff).
When a microwave hits metal, it essentially just bounces off. That's why your microwave oven is lined with metal, and it's why there's a mesh on the window (that's also metal), it bounces off of that too because the holes are small enough.
The reason it bounces off is that inside a metal, there are lots of electrons (tiny charged particles) that are free to move around. That's why metals conduct electricity, the charge can flow around them easily (it's also why they're shiny). When a microwave hits a metal, the electrons inside the metal get pushed around by the wave, and they kick back a new one because of their motion. So, metals reflect microwaves.
What's tricky is that when all those electrons move around to reflect the microwave, they sometimes end up clumping together. This is especially common on the object's edges: think the tines of a fork or the blade of a knife. The reasons for that are... mathy, to say the least, so let's just say that it happens.
So, lots of electrons clump up on the blade of your microwaved knife, and since there's so much charge collected together, they arc. Arcing is when electric charge jumps through the air from one spot to another: lightning and static shocks are both examples of arcing. It's that arcing that causes fires and such when you microwave metal.
The walls of your microwave are designed in such a way that they don't arc: the shape (the *interior* of a box) doesn't have those sharp edges like a knife, so the charge doesn't collect in a dangerous way. It just spreads out evenly, and everything's fine.
Again, **don't fucking try this at home seriously**, but you could absolutely safely microwave a spherical metal object. The issue is that if you tell people it's *sometimes* safe to microwave metal, people would, you know. Die.
edit: I should say, you could safely microwave a spherical metal object if there was something else in the microwave. Otherwise, it would be the same as running an empty microwave, which is also something you should not do. | 8c44645b-ab4b-41d5-a83d-d4f19c517b0f |
2acglo | Can 2 or 3 people have the exact same voice? | Close enough to cause confusion, anyway. When I was in high school, this happened more than once:
SFX: Phone rings
My Dad: Hello?
(pause)
My Dad: I think you must want PossibilityJones. Just a moment. PossibilityJones! Phone!
Me: Hello?
My Girlfriend: Stop it! You're just screwing with me! I know it's you all along! | 00e57c2c-f7d5-43e6-9a4a-8619809f7e3f |
65hmci | How are the songs on the radio encoded into radio frequencies? | If it is analog radio there are two ways AM and FM.
In both cases you have a carrier wave at the frequency you set your radio to. The carrier wave has higher frequency then the sound. The sound you can hear is < 20,000 hz and the carrier wave is in the 1,000,000 hz range
AM (amplitude modulation) changes the amplitude of the carrier wave with the amplitude of the sound ie a multiplication of the signals.
FM (frequency modulation) is more complex and you change the frequency of the carrier wave with the amplitude of the sound and keep the same amplitude.
You can see an [animation] (_URL_0_) on the wikipage of how it looks.
And if the question is for digital radio then the answer is more advances because the song is encoded like a mp3 on a computer and then transmitted digitalt on like hos WiFi works (not the same but similar). | d2bf9054-35f8-43b0-b812-cab45752864e |
1m942u | How are nearly perfect polygon (usually hexagon) bubbles formed when I submerge a drinking bottle, with a circular mouth hole, under water and let the air escape? | For the same reason [these suckers](_URL_0_) make hexagons; it is the least amount of edging surface required to make the cells or bubbles. | 0e7ec837-5962-497b-825f-00e4a9e179cf |
1xu8e7 | How are jars vacuum-sealed? | The contents are heated as they are packed, at very least to pasteurize them. Lids are applied hot, and as the content cools, it creates a partial vacuum. | 533e7a6b-d906-43bb-88b2-241e1ecf0b0e |
6b7663 | Why do Americans consider Barack Obama to be black when he is actually mixed? | By American convention, a person is black if they have basically any black ancestry.
And more importantly, Barrack Obama self-identifies as black. | 33f5e20a-9f85-4b38-b6e2-f305c538db21 |
4bw03g | why animals like pandas can eat just one plant and don't have any lack of nutrients | They do have a lack of nutrition that's why they sleep 90% of the time,
Its why they have to eat almost a ton of bamboo a day to survive,
They don't have enough energy for sex which is part of the reason they are going extinct. | cb96e8b7-6eff-4060-9812-8ebf129bd7ad |
2zzosd | When a massage therapist comments on how tight your back is and how you have so much going on in your muscles and trigger points, does that mean something is actually medically wrong? | Not necessarily. People can have tight muscles because if stress or over use, etc. This is not to say that a person with lots of tension can't have other problems, but that I just normally is not the case.
When a person is new to receiving massage, certain things can be expected. They will often be told what their problem areas are, and they are different for different people, for example, a dancer or a runner is going to have in most cases different problem areas than an accountant. How well hydrated a person is (or is not) can also have an effect, as even mild dehydration can contribute to muscle pain, or spasms. This is why they like to give you water afterwards. Lightheadedness is possible after a massage, so it's always best to get up slowly. Sometimes a person can be sore the day after a massage, especially if deep tissue was done, but if it lasts more than a day, the therapist was applying too much pressure.
A massage therapist should never diagnose, as it is outside their scope of practice, however, if he or she really thinks you have a medical problem, they can suggest you see your doctor. It is not the tightness of the muscles that will be cause for a therapist to consider this, but other factors. Perhaps moles, or other skin issues, but most often information that is communicated by the client.
I have been a massage therapist, licensed by my state, since 2009. When I think someone has a medical problem, I don't ignore it. When someone has large or multiple moles/birthmarks, I ask if they get their skin checked, or if they were aware of the ones on their backs. I've had people thank me for this before. After having a few regulars explain symptoms to me, I have suggested they see their doctors for blood work. They always come back and tell me what they find out.
If a person often complains of numbness, burning, or tingling sensation in their limbs, I suggest they see a chiropractor as well, as most often these are nerve symptoms, and chiropractic adjustments may take the pressure off the nerve (often nerves are impinged by the vertebrae)
Anyway, sorry for the long reply, I hope you found this useful. | 9074c17c-2d43-46f7-ab1e-24b8378fb88f |
j3dz0 | Can you explain to me (like I'm five) what microprocessor stepping is, and how it works? | The speed usually advertised on your microprocessor (like 2.8ghz) is it's highest speed. When the processor is running at it's highest speed, it can do the most amount of work (and fastest). But running at the highest speed also makes it use up the most amount of electricity.
What microprocessor stepping does is limit the speed of the processor to only what it needs for it's current job. For things like typing an essay, or browsing reddit, a modern microprocessor usually needs very little speed (sometimes even less than 25% of it's maximum). But if you are watching a movie, or playing a video-game, it will probably need all of the speed. Almost all processors today use stepping to conserve power, while still being able to do the most complex tasks you need. This feature is built into the microprocessor, and can be used by any operating system (Windows / Mac / Linux) to control the processor's power usage.
Hope that explains it :) | f30a9bc4-b705-44e3-ad20-eb349080f47c |
5hmojk | Explain me voltage, electricity and current like I'm literally 5 | Electricity is the build up of electrons.
Current is the movement of electrons.
Voltage is how hard the current is being pushed.
Amperage is how many electrons are being pushed. | 0fb66f03-ef79-46c5-babc-c8527aa0f181 |
1eq25t | Bose-Einstein Condensates | Preface: I'm doing a minor in physics, and just aced, my intro to quantum physics course, which (in addition to the introductory physics course I took last year) covered this. However, I am far from an expert.
So, in order to explain what a Bose-Einstein Condensate is, we first have to understand some things about Bosons, and fundamental particles. So, in school, most of us learned about atomic particles: protons, neutrons, and electrons, however that model (proposed mostly by Niels Bohr) was found to be incomplete. In reality it turns out that there are even more fundamental particles than protons and neutrons (electrons exist on this smaller scale as well). There are two types of these particles: bosons and fermions. The key point of Bosons is that they can exist in the same quantum state, basically, this means that multiple bosons are exist in the same place at the same time.
This allows bosons to form Bose-Einstein condensates. Essentially, the bosons all congregate in one place, and this forces the tempeture of them to become really, really low, in fact its becomes so cold, that it approaches the coldest temperature that can exist in the universe (0 kelvin). This is important, because it allows us to observe quantum effects on a much larger scale than we normally can (whats known as macroscopic level).
At this point in times, Bose-Einstein condensates have no "real-world" value, and instead are used to study effects at the edges of our understanding of quantum effects, primarily examining quantum interference effects (how quantum particles affect each other). | 474c868e-be6f-4523-8ccb-6f7d9013abf9 |
56fl2b | Why do movies use a green background to film with CGI and not other colors? | Green is generally the farthest colour from human skin tone, being the opposite of red, so when it comes to removing it you avoid issues with holes in the person. Also modern digital cameras devote twice as many pixels to green as for blue or red, so they're a lot more sensitive to the green spectrum. | 1a5e6062-5a07-4773-8a54-0adfabdd79e8 |
qev9l | Difference between a key change and mode change in music. | From what I understand all the modes retain the same base note. So if you know enough about whatever mode they are playing in you can figure out what note they keep ending with or going back to. When you change the key the base note is different. For example the difference between C major and C mixolydian is that in the latter the 7th note goes down a half-step. They both have the same base note (C), but the scales are different. | 5635fd28-4c7f-47ed-8587-12bcf4e3f601 |
8wpswd | How does discarded yard debris, such as a pile of grass clippings, get hot enough to combust? | I'm confused as to what you mean, but here's what I think you mean: "How can very green plants burn if there's so much water in them?"
Water interferes with combustion because it boils at a lower temperature (usually) than the thing that we're trying to burn.
This is important because water stays at the same temperature as it boils, so the material can't get above that boiling temperature until all the water has boiled.
Boiling water takes a ton of energy. The energy released by the material burning has to be greater than the amount of energy needed to boil the water and ignite surrounding material.
For a damp log by itself, there's no way. But if we get a nice fire going, the energy released by the fire will be more than enough to drive off the water, allowing the wood to burn. | b9267c5f-aa87-4838-b407-6ec364f9ddb0 |
274zwk | Why can't electric cars charge themselves like combustion engines can charge it's own battery? | Because the combustion engine uses the combustion to charge the battery via a generator (alternator in a car). The electric car uses the battery to run the car. So using a battery to charge a battery is both pointless and will result in a net loss of energy due to heat.
Also, electric cars do charge themselves when you use the breaks or are coasting downhill in cruise control and it's slowing you down by applying a generator to the drive shaft (?) causing resistance while generating electricity | 79691e90-5bba-4499-988c-fb6bed850ccd |
59is37 | How does Shampoo and Body Wash work so effectively when it only stays on our body for a few seconds before getting washed off? | If I understood correctly, you are basically asking how soap works.
Soap/shampoo/body wash has molecules that can interact with both the water and the fat/dirt you want to remove. These molecules have a polar portion, which binds them to water, and an apolar portion, which makes them able to interact with organic matter (fat, dirt, basically what you want to remove when using soap). So in a way, soap allows the organic matter (dirt) to become "soluble" in water. You're not really destroying the dirt molecules per se, as much as allowing them to be washed away and go down the drain. | 34ed888d-f135-4129-89ad-a692091076b7 |
1hqcc1 | Why is red, white and blue so prominent in flags throughout the world? | Red often symbolizes bravery, courage, or blood shed in warfare. White usually symbolizes purity and peace. Blue symbolizes peace, justice, and vigilance. | 9425e7f3-5602-49f9-a5aa-06db21a4171b |
sk8mg | What is mitochondrial DNA and what it tells about human evolution | You live in a house, but you have some extra room. So you let your friend come over and live in a room in your house. He has his own stuff for his room but uses your kitchen, bathroom, washer/dryer. In exchange he pays for your power bill.
This is a symbiotic relationship, you help each other. Mitochondria are the remnants of a once fully independent species of bacteria that fused with larger bacteria and formed a symbiotic relations (this occured over hundreds of millions of years). The mitochondria, when they first moved into the cells of our ancestor bacteria brought some of their own stuff, one of which was it's own DNA, which is still found in them today.
Mitochondrial DNA don't mutate as much or as fast as regular DNA, and they are only passed on from your mom (they were present in her egg cells when it fused with the sperm). So now we have a really good marker for tracing differences between broader cultural and ethnic groups. | 59fccbdd-de5b-46f5-afe6-c1149704cdec |
1mc1g5 | Why does squinting improve my eyesight when I don't have glasses on? | Glasses bend the incoming light to focus it appropriately to the back of your eye. When you squint, you're doing the exact same thing, but very imprecisely. It bends the light just enough to help you get by in a pinch. | 1757b11f-e49b-4160-a4af-2c7c7a1dc4d8 |
40uyl1 | Why are some economies self-sustaining while others require a massive trade surplus just to function? | A lot of the value produced in the USA is by peoples brains and not their hands. If you import a ton of cheap garbage from china for pennies and export knowledge in medicine, engineering, business, finance, etc. For hundreds of dollars per hour, its hard to look at that as being BAD for the us. | 83d313b3-1359-463d-9e36-14f7d2485c8a |
1sn81m | If two half-asian, half-caucasian people have a baby, is there a small chance only the caucasian genes are passed on? | Mathematically yes. Statistically no. That would require:
- that each parent had EXACTLY half of its genes from each origin, which is a very small chance.
- that they have EXACTLY complimentary halves (every gene that was asian in one parent would have to be caucasian in the other parent), which is again a very small chance.
- that the chromosomes all crossed over at exactly the right place to switch it out, which it another very small chance. | 0a9af42d-4849-45b2-b6fc-8e819f3ba2ff |
455mkd | Why does our electoral system have "super delegates" who don't have to cast votes matching the popular vote of their district? | It's not really "our electoral system", it's the Democrats' nomination process that has it.
Technically, those people don't have to cast votes based on anything, but the majority are almost certainly going to vote for whoever ends up winning the vote-based delegates. It came up in 2008 - a lot of superdelegates came out to support Clinton early on, and ended up switching their votes to Obama after it was clear he had won the popular process. It'd be political suicide for the party to swing the vote away from the primary results.
As to why it exists, the cynical reason is that candidates do a lot of work to try to convince these superdelegates to come out in support of them early on in the process, and they don't want to lose that feeling of importance. | 9ae47e7b-2c06-4eda-a33b-859939bd27a8 |
4r3bx9 | How does the body make blisters? | heat damage increases capilary permeability and plasma (the liquid that supports blood cells) "leaks" under a thin skin layer, getting trapped under it. | 6eb7fac3-bf0f-42e2-85fb-95ae6dfbbab4 |
29bufj | What causes the side effects of antibiotics, and why do they put "take with our without food" on the label when I fell like I'm going to throw up whenever I take them without food? | You have bacteria in your gut that help you absorb nutrients. These good bacteria are also killed when you take broad spectrum antibiotics. | 4ea1ba47-d0b7-40d7-a51b-f7e4188dc0f7 |
2dstvt | Why do we hear about so many soldiers in the present day wars in Iraq and Afghanistan returning with PTSD, yet it seemed to be nonexistent in those returning from WWII? | Back then it was called shell shock. Damn sure happened frequently but just not as discussed much like most mental illnesses | 9aed6a7d-dea1-4515-8683-41ce7622fe5c |
1kszph | Evolutionary History of Pandas? | I suspect it is because of their diet. Taxiphyllin, what babmoo shoots produce, is a toxin that produces cyanide in the gut. So most animals can not eat it or in large quantities. We can only eat bamboo after it has been prepared correctly.
Basically the giant panda was able to survive because it could eat a plant that most animals could not. | f21fea2e-da4f-4f72-a85e-9eea1a1b9aec |
2v7x63 | Why can't Palau, Marshall Islands, and Micronesia provide for themselves and not be in Free Association with the United States? | Ever since WWII ended, there has been a strong decolonization movement throughout the world, and many countries are either granting their overseas possessions independence, or giving them full status as an integrated part of the nation.
Many of these places want independence, but aren't equipped to take on all of its responsibilities. Many of them take intermediate steps first, like a free association, before they are ready to break free entirely. | 9c5f2f30-411a-444b-926c-07560e6ae941 |
3jl5mw | Why does Google Maps suggest a slower route? | The problem is if two places are far away there are too many possible ways to travel. Instead google thinks of points along the way and calculates the fastes way between those points. It then adds those ways up. | 418875ac-b63d-4247-a230-d35e2fbd31e1 |
8f6cey | how do birds mate, and why can we still eat an egg? | The chicken eggs in the grocery store have never come in contact with a rooster. They are unfertilized eggs. | 2580e5f1-96e5-4230-9e62-877f71613c11 |
1lp7p5 | Why is a bra just called a bra when it covers two things, but a pair of panties is called a pair when it only covers one thing? | We don't call them a pair of shirts either. Panties came from pants, and pants originally came from hosiery, which came as two separate pieces. We kept the "pair" nomenclature even after we starting joining the two leg pieces together in the middle. | 68eeba56-bc0f-4c12-b53a-4052e485fb1e |
1lamqd | Why do some say Diet Soda is bad for you? | First things first: diet soda is *not* known to be bad for you.
Now for the elaboration.
Diet soda is soda that's sweetened with something that isn't sugar. The thing that it's sweetened with tastes sweet (obviously) but has no nutritional value. So diet soda can taste sweet while having no nutritional value to it whatsoever. Nutritionally, it's basically equivalent to tap water.
Some people assert that the non-nutritive sweetener itself is harmful. This is generally not supported by the facts. There are a variety of non-nutritive sweeteners on the market, and some have been subject to more scrutiny than others. But *all of them* have been tested for safety in humans and found to be okay to consume. They can't be sold otherwise.
A couple of the non-nutritive sweeteners, in fact, have ended up being the most thoroughly tested food additives in existence, specifically because people keep asserting that they're harmful. These are saccharin and aspartame. Saccharine is actually an example of how food-safety testing can go wrong and generate a false positive; it's a fascinating story, but I'll skip it in the interest of brevity. Aspartame, on the other hand, has *never* been shown to cause any kind of problem in anybody. Both are absolutely safe in responsible quantities.
Now, there is some interesting data out there about the relationship (if any) between the consumption of diet sodas and weight maintenance. One would think that since diet sodas are nutritionally void, consuming them wouldn't contribute to weight gain, right? Some correlational data suggests otherwise. In some studies, people who regularly consume diet sodas gain weight more and more quickly than people who don't.
Trouble with that is, those studies don't control for other lifestyle factors. If you drink three diet sodas a day and run four miles three times a week, you're probably going to control your weight better than if you drink three diet sodas a day and live a sedentary lifestyle while eating McDonalds every other day.
Meanwhile, other studies show that there is in fact no correlation between weight maintenance and diet soda consumption anyway. So at best, there's no conclusive trend there yet identified.
Now, there has been a specific assertion about diet soda. It's that if you consume diet soda, you're getting *sweetness* with no nutrition. This, it was hypothesized, might affect your *appetite,* by reducing the *satiety* you get from eating. In other words, it'll make it harder for you to eat responsibly, because you'll be "tricking" your brain into thinking sweet things have no nutritive value.
The interesting thing about this assertion is that a rat model supported it. Rats were given artificial sweetener and did, in fact, eat more than the control rats.
However, when the experiment moved to humans, the opposite result was found. People were given fMRI scans — which show activity in the brain — while sipping either on water sweetened with sugar or water sweetened with an artificial sweetener. The ones who got sugar showed dramatic activity in their brains, while the ones who got artificial sweetener didn't. So there's no evidence that drinking diet soda can screw up your appetite in the way that was suspected.
So the short version is that diet soda is not known to be bad for you in any way. But like everything else, don't go nuts. Be responsible. | 7e92d6a1-2947-4e05-b698-8c4d918dc132 |
2fd4ow | - Why is it that Peter Pan is portrayed so much by women in plays and new reboots of the story? | It's much easier to make a woman look like a 14 year old boy than it is to find a man that looks like a 14 year old boy. | 8eb79c65-cc5a-457d-9d4f-e916843f0c77 |
2wlixo | Why do I get hiccups after one tiny swig of whisky? | Hiccups are a result of one of three things : expansion of the stomach, movement of stomach acid or irritation of the phrenic nerve, which controls the diaphragm.
As it is unlikely that a swig of whisky can cause the stomach to expand, it is most likely whisky irritating the phrenic nerve or a less likely, a quick reflux action of stomach acid. | 6fd6b571-706c-4381-92ca-0b3bede1242d |
2j160d | What would happen if every single American with student loan debt simultaneously defaulted on it? | The banks would be bailed out by the government, who insured the loans.
Taxpayers, including those newly-graduated and working debtors, would have to make up the losses in higher taxes.
Deadbeats would lose their credit rating, and have to pay exorbitant interest rates for years to come.
Student loans would become prohibitively expensive and fewer of the next generation would be able to attend college.
The job market cannot find adequately-trained Americans and seeks visas to hire foreign guest workers. | 0d529c65-0170-40e2-8158-572f537c0a96 |
15msaz | What causes the need to pee? | It's been a while since I've studied it so I can't elaborate too much. Basically after we reach about 200mL of urine our bladder stretches too much and we feel the need to pee. I was taught that every 50~100 mL of urine will re-trigger this feeling until your bladder can't stretch enough and is forced to contract which causes you to pee.
The nerves are called the pelvic splanchnic nerves which is part of the inferior hypogastric plexus.
_URL_0_
Source: Working on my masters in exercise physiology
Edit: If you want to read about [the plexus](_URL_1_) or the [Splanchnic nerves](_URL_2_) | 4f1c5566-4ee2-49cb-b0d5-094939a4f59c |
4eo4mk | When you burn your tounge, why does it feel like a different texture? | The answer is in the question. Burning skin damages it. If it's damaged, it's going to be a different texture until it heals.
Also, your tongue has nerve endings just like the rest of you. The tongue itself can feel things. When burned, those nerves aren't working properly any more.
So your tongue will feel different to the rest of your mouth, and your mouth will feel differently to your tongue. | 1d119b0c-bcfe-469b-934d-dd63ee5f56d5 |
p1697 | What is the purpose of the "Do not eat" packets often found in packaging? What would happen if it was to be consumed? | it is there to absorb moisture and keep the thing its packed with dry.
it is non toxic but may irritate your digestive tract..
btw its silica gel
_URL_0_ | 9ee5fee5-be32-4218-8054-e874f01e9106 |
8qv574 | Why can reading glasses be purchased over the counter, but glasses for nearsightedness cost hundreds of dollars? | As I understand it, "reading glasses" are basically wearable magnifying lenses at various strengths. Glasses for nearsightedness (or farsightedness) are far more than that - in essence, they need to be carefully shaped to reverse the abnormalities of your natural lenses and eyeball. This is a somewhat complicated calculation, and the cost of the glasses reflects the complexity of creating your custom lenses. The charge for an eye exam is completely separate from the cost of a new pair of glasses. | 36ffb48b-aa07-4051-a943-d473640bcb00 |
8rgy59 | how are ETFs priced? | Each share of the ETF owns very specific fractional shares of the other stocks. If we have an ETF that is 0.01 shares of AMZN, GOOG, and AAPL per ETF share then it should be priced at 0.01*(1715.97+1152.26+188.84) or $30.57 per share.
If you were a market maker and you owned a large number of shares of this ETF, you could turn them into the underlying assets. If you have 1 million ETF shares you could trade them for 10,000 shares of AMZN, GOOG, and AAPL which you could then sell for their listed prices. You could also take 10,000 shares of each and turn them into 1 million shares of the ETF
If the price of the ETF diverges from the price of what it contains then this creates an arbitrage opportunity(free money) where you can buy the stocks cheap in one form and sell them for a profit in another. The automated traders are quick to take this chance for free money so the price of an ETF is usually pretty close to the price of the assets that make up each share of it(the net asset value, or NAV) | 72b7b250-a72c-4a48-8e8d-b62a6ffeae79 |
1jaj2h | What is GitHub, what is it used for, and what do the key terms like fork and commit (there are others too) mean? | Git is one form of revision control, there are many others like subversion, etc. Revision control exists as a means to manage contributions and updates to code, especially code that multiple users work on at the same time. It does this by keeping track of all changes made, who made them, merging different changes together into the same code, allowing you to roll back specific changes, allowing you to work on two different versions of the same code (for example, live and development), etc. Typically, there will be some sort of central repository which collects all the submissions from various people, Github is one of them. In case of Github it's great for open source coders to work together, or possibly even small companies (large companies will likely have their own repository rather than relying on a third party website). Another advantage of a site like Github is that if you have written code that others use, and there's a bug that needs to be fixed or even a feature someone would like to see added, they can grab a copy of your git, make the changes, and then submit them to you (at which point you can accept the changes or reject them).
As for terminology, there's a bunch, I'll go over a few of the common ones. This is based on Git/Github terms, some of them may be slightly different depending on what you use.
Commit - You submit changes made along with a description of what changes were made
Push - Push local changes to the central repository (until you do this, all your changes are only local)
Check/Fetch/Pull (I've seen all of them used) - Grab latest version from repository
Fork - Make a copy of an existing git. If you like someone else's code and you would like to start developing it in a different direction, you might do this, or if you find a bug in their code and want to fix it you would use then and then use...
Pull request - Someone forked your code, made changes, and requests that you accept their changes into your git. This is great when it comes to helping out with major projects where there's always a lot of things that need fixing.
Branch - As mentioned above, when you want to work on two different "versions" of the same code (such as live and development).
Merge - Combine two branches together, or in general combine multiple changes into one version that has all of them
Conflict - If, during a merge, specific code was changed by both versions being merged together, the version control won't know which one to pick, so it needs to be resolved by selecting the correct one
I'm sure there's tons more I can't think of right now, but that covers the basics. | f9992904-abf3-45b2-8355-4dc987b0219f |
59j70n | How does "declaring war" on a country work? And how does a country know who is attacking them? Couldn't the US go bomb a country and say another country did it? | Yes, a country's leader could go attack another country and blame someone else. However, the complexities in chain of command and the number of people that would be required to know are so high that people would find out eventually. Even Russia, which Putin keeps on lockdown with state-controlled news and the like, couldn't keep their invasion of Ukraine a secret indefinitely. With a free press and a division of power like in the US, it wouldn't take long at all for someone to start putting the pieces together.
At the very least, if the President did start to wage some sort of "secret war" without Congressional consent, eventually things like soldiers and ammunition and fuel would start going absent. When it came time for Congress to pay the bills, they'd find out and be pretty upset because it's exclusively their power to be able to formally declare war.
World War 1 was officially declared by the German diplomat to the Russian prince, to give an example. Nowadays it's difficult to say how a country like the US would declare war against an equivalent power, because would you really want to give a nuclear power forewarning that you're about to attack? | 2e3e7593-cf3f-4575-afdf-6c45f50a5f5a |
65r2ma | How do muscles get stronger as you workout? | In a couple of different ways, actually. First and foremost they get stronger with lots of exercise because they get better at recruiting more fibers and contracting harder, which is mainly due to the training effect on your central nervous system. Secondly the muscles themselves get little micro tears in them as you lift weights. When these little tears heal back your body heals them back bigger and stronger than they were before. | 2b912f77-cbd0-49d4-aa40-097e4f09d5cd |
5wsqpw | how are chip cards more secure than swipe cards? | The chips generate a rolling code and would be imposible to predict or duplicate. So suffice it to say that you cannot spoof the card.
So unless you actually steal the card (easy to identify and report) you are out of luck.
so any retailer that uses a chip is effectively immune from credit card fraud or atleast bogus claims of fraud. | f283899d-33f0-4760-ad36-a1ee75823cd4 |
22htpo | If I do something illegal on the internet, how can the police track me down? | I doubt that they would unless you did something that caused physical harm to someone or something. | 36cad802-e248-4f8f-80ee-f5d6d177c3f7 |
30p84o | Why are rainbows always curved? | Rainbows are actually circular, however, ol' earth gets in the way. But there's more to it, too.
The sun's light has travelled so far that it's coming basically straight at us, there are droplets of water in the air that splits the light apart into colors, and bounces them back towards you. However, there's only a certain area where the water can be where it's perfect for this.
The real reason, however, is because water droplets are round. So since when they're at a certain distance with light coming in at a certain angle, any droplets in that circle will project those colors to your eyes. | 903b6cfc-687f-4353-a3d6-4a47c48a07d9 |
7xe2qz | Why do obsessed fans develop the desire to kill celebrities or the object of their obsession and idolization? | I'm sure someone with psychology credentials will come up with a much better response, but my guess is that it has something to do with a sense rejection. These people "fall in love" with the people they are obsessed with and feel rejected that the feelings they have are not mutual. In extreme cases this manifests in a real world way (e.g. they stalk their obsession and there are legal repercussions) but in many it's probably mostly imaginary or fantasized. Out of rejection-driven rage they get revenge by trying to kill their obsession and/or they attempt this based on the "well, if I can't have you then no one will!" mentality. In any case, I'm sure that there's also some undercurrent of jealousy in play as well. | c27e1594-11d0-4880-bb83-f66775057a87 |
2vwyi9 | Why does it feel warmer when it's snowing outside, compared to it just being cold without snow? | Bunch of wrong answers here...
Snowfall implies negative degrees celcius (otherwise it would rain). As the temperature drops below zero, the humidity in the air quickly drops aswell. Dry air is much easier to shield yourself against than humid air.
This is why 1 degree celsius above zero is such an awful temperature. You get all the cold with the humidity. | f1948f5d-4f3b-40c5-b437-f2820d76f106 |
6fy7bs | What are “non-free” packages in Linux? | Used in debian-style repositories and others, the non-free section refers to packages that do not have source code published under a "free" license. Such packages/software are distributed free of charge, but the source code is not available and/or users are not allowed to modify and create derivates of the code. | a4e3824a-4d5c-457f-a0f1-6b72d90194a5 |
5kl1gb | Why does an explosion "suck in" the surrounding environment and then light up? | There are three different aspects to that that together form your "explosion":
1. If anything gets "hot", it starts to emit light. If air and gas get hot because of a chemical reaction and as such starts to glow we call that "fire".
2. If anything gets "hot" it expands its volume. If you make gas very hot, it expands outside and pushes everything away. That is what we call "explosion".
3. If the gas in 2. got pushed away "fast" and "thorough" enough, the original spot has lower pressure ("less air") than the area surrounding. If you want you can call that a weak vacuum. The air around (and all other gasses) flow back and if that flow is strong enough, it can "pull anything with it", i.e. the "sucking in" from the title.
If you have a "lot of heat" very "sudden" - then the "expansion" and "lighting up" happens very fast. That is what we call "explosion". If it was *very*, *very* sudden, you also can get a "sucking" effect, but you need a really sudden explosion for that to be significant, the "throwing away" is usually much stronger.
(Thermobaric bombs are made to create a very strong, sudden blast and they can have that "sucking" effect, i.e. [non-ELI5] shredding people's lungs.) | 0d5fbea8-fa5b-42da-99b4-5980d08c5fd9 |
25wrqj | Is there a scientific reason my room gets colder with less stuff in it? | When you've got a lot of stuff in your room, you've got less air in it.
In the same enclosed space, it takes less energy to warm a smaller amount of air than a larger amount.
So when you have less stuff in your room, you have more air and better circulation, and it takes more energy to warm it, and if you're the only source of energy, it's not going to warm as much, and will feel colder. | b4cdeccc-8499-48d8-999d-4ad99b201680 |
6nqcdc | PCOS and birth control | You may want to ask this in /r/PCOS. There will be a lot of women there who have been through the same issues you have. | 338e996b-b26c-4c72-9cdb-6855a19bc61f |
15d6ya | Why does my nasal sinuses clog up once I lay down to rest? | Nasal sinuses are essentially holes inside your skull that clog up with mucus (snot) when you have a cold.
Each of these sinuses have an opening in them which allows the mucus to drain from the sinuses into your nasal cavity (inside of your nose). Most of the sinuses have their drainage openings on the bottom of the sinus so when your head is upright the mucus can drain into your nose pretty easily via gravity. This means that when you are lying down, they tend not to drain so well and clog up. | 5ed5ed7b-de04-4341-a549-2100d2743754 |
2yuqj4 | Why do we have a bracketed tax system, and why don't we use flat tax rates for everyone? | As ELI5 as was explained to me: A flat tax, like 11%, would be a larger share of a low earning citizen than a high earning citizen. A person earning $100 would be more affected by paying $11 dollars than a person earning $100,000 would be paying $11,000. | 19719806-2ce7-44c6-a357-527f5d1c8467 |
1zvicm | How Bi-Planes are able to time/shoot their guns without the bullets hitting the propellers. | While all of the responses so far are good (the wiki link explains quite well in-depth, with illustrations), I'd like to try making this as ELI5/TL;DR as I can:
The pilot's trigger is not really the same as a trigger on a handgun - it does not make the weapon fire. Instead, it works more like a safety - when pressed down the safety is off. The trigger is attached to the propeller - the propeller will pull the trigger each time it is in a position where the bullet will miss. | bbd4c3e7-ab4c-4da9-92cd-46d33959dd6e |
3ge1kp | Does wearing a hat contribute or cause hair loss in any way? | You said in any way. Yes it can, if you have psoriasis, wearing a hat can trap heat and sweat, aggravating the condition. Which can cause temporary hair loss.
Otherwise generally no. | 099c9eb0-fa74-4ebd-b166-b71950534328 |
2wy52a | How do babies learn languages so quickly? | Not like they have much else to do, poopin' don't take too much time. | 1ba6a8ed-fb4d-41ef-8e14-4ac1714c9142 |
3wq9iw | If every company that has moved "hq" overseas suddenly had to pay the taxes owed to the US gov't, what would happen? | The better question is: why should we tax worldwide profits of corporations anyway? The taxes that they are avoiding by moving overseas are **taxes on profit (edit: typo) made outside of the US**. We are alone in doing this, since every other country in the world only taxes corporate profit made within their borders. It doesn't make sense, and it puts American companies at a disadvantage internationally. | 70706ae5-f33d-4e92-b860-8c5c66e3f777 |
5pahgk | How exactly is data transferred wirelessly? Bluetooth, Radio, Satellite, NFC, Wi-Fi, Li-Fi etc? | Imagine the hose in your garden. Its connected to a faucet. If you open and close it fast enough and in a pattern, water comes out of the other end also in a pattern.
Now, devices have recievers and transmitters. These know how to "read" and "write" patterns respectively. We can now set this up so that certain patterns can mean certain symbols. A collection of symbols can ultimately form an email, a message on facebook, and more complex streams like pictures and videos.
in real life, these devices turn on and off at tremendous speeds, and as a general rule, the faster you can turn on and off, the more information you can send in a single time frame. | 0cfad1dd-4100-4730-8466-cd07322395a3 |
u6p37 | What it means to cut someone off | Basically it is when another driver passes your car, but gets into your lane without leaving reasonable space between your front bumper and their back bumper.
This can be, and often is, accompanied by the offending driver immediately reducing speed to compensate for sliding in between cars recklessly, creating the potential for you rear-ending them. | 1c6111ce-e735-45bd-83b6-e5fde603d87f |
3lbsht | Is there a reason that some devices (like a remote) have their batteries installed in opposite directions, as opposed to a flashlight which does not? | When you put batteries in *series* (i.e. stacked up end-to-end), their voltages add together but the current stays the same.
When you put batteries in *parallel* the voltage stays the same, but the currents add together.
Installing the batteries in opposite directions is a way of putting them in series without having to have a really long thin stack of batteries. The top of one battery connects to the bottom of the next, and so on. | 32a00fd1-3245-408d-b185-a255620b7d3e |
4d4qmx | How does carbon dating work if all of the atoms being tested were originally created in stars? | That's because the Carbon-14 was not made during the big bang, or even when our sun and the earth were formed. Carbon-14 is constantly being created by decay of Nitrogen-14 in our atmosphere. When something is carbon dated, it's dating the carbon that was created during the lifetime of that organism.
Radiocarbon dating is really only useful for organic material, and only to about 50,000-60,000 years ago, due to the half-life of Carbon-14. | 336e0927-a954-4042-a274-cd0262c24550 |
2bxgs2 | Why are certain animals (e.g. dogs, cats) domesticated more commonly than other animals (e.g. deer, raccoons, etc)? | Dogs and cats are better suited for the tasks we give them. There is not a lot that a deer can do that something else we have tamed could do more efficiently. Although reindeer are used in extremely cold environments that would not be good for horses. | 1f9d26a1-4fec-4f68-bdf6-b01ef9c34c42 |
33bq5o | Why does it start to rain much more heavily immediately after thunder? | Thunder is produced in a type of cloud called a "cumulonimbus".
In this type of cloud, air gets pulled higher and higher by the air currents. As it does so, its temperature decreases, and because cold air can't hold so much water in its invisible gas form, the water turns to visible liquid water droplets.
Eventually these droplets get large enough that they can't be carried in the air current any more, and they start to fall.
This on its own would be enough to cause rain. But what makes cumulonimbus different is that the rain drops get caught in further air currents on the way down, and get carried back up into the cloud again. The cycle repeats many times, with the rain drops going up and down many times, *each time getting bigger*.
This movement results in droplets rubbing against each other and building up an electric charge, which is why we eventually see lightening and hear thunder. And the movement also results in the droplets getting bigger because they spend so much time in the cloud, resulting in heavier rainfall. | 1b0d310f-821c-438b-938c-867f475f0910 |
2ef3m3 | How does a song "grow on you" after a few listens | Our brains like repetition. We like being familiar with something. So after you hear it multiple times you "know how it goes" and automatically start liking it better. | c0c2a907-1683-4c06-b8b2-9471f6254baf |
243nyw | Why, when I have a headache - If I bend over or bend down, the headache becomes instantly much more painful until I stand up straight again | Increased pain when you bend over or press on the area is symptomatic of a sinus-related problem, possibly a sinus infection. | 3607958a-0d1c-4632-8bd8-6f2662f8210b |
1yoa5m | Why do University computers get a 200+Mbps connection while my laptop only gets 10mbps. | Gigabit speeds are pretty much restricted to *wired* connections. Shared wireless isn't up to the task. | 0ee9017a-fbc2-4552-8cfe-68d3523e34f7 |
8hxoh3 | How do mirrors have different levels of "zoom"? | By being curved - Convex mirrors have negative magnification, making things look smaller than they actually are. Car side mirrors are very slightly convex so that you can see a wider angle of view, which is advantageous when driving. Concave mirrors like those on a telescope are the opposite, having positive magnification. | 41f25fec-2d69-4a16-8cb3-14718cc77bfe |
wlasq | so why do companies make mail-in rebates? | People who are attracted by the rebate price and buy it, but never mail it in. | 5027e498-9179-406c-8cc4-9fd50a4d3eac |
1xmppc | Why do people keep buying EA games if they know they will have to 'pay-to-play'? | Because EA games is the biggest player in the gaming industry and they make a lot of games.
Remember that Reddit is a forum for people who have a problem. You don't hear the people who are happy because they are either downvoted to hell or too busy having fun to engage with those who are unhappy.
EA is making an unbelievable amount of money off of these games, otherwise they wouldn't make them. A few people pissing and moaning on Reddit isn't going to stop them if the profits keep coming in. | 591cfee4-afed-4abe-b48b-cec08f1be9cd |
2ikdnu | Why are razor cartridges so expensive? | 1. People pay that much for them
2. Once you buy the handle, since each has it's own interface, the choice to swap razors includes more costs than just the difference in blade prices.
3. The major razor companies pay stores enough to ensure that only a few brands will fill the shelves.
4. Go check out Dorco Razors or old-style double edged razor blades, for much less expensive options. | cf46ab8a-d590-493f-8a82-ae8fe8b6ac37 |
2ugdz4 | The enormous salaries of professional athletes. When did this madness start? Is it a result of owners, players, or consumers? | Let me ask you this, what would you rather be done with the money? If the sport is making enormous sums of money, based on the efforts of the players, would you rather the money just go to the CEOs of the sports team?
If you look at professional athlete's salary as a percentage of what the team makes, as oppose to how many dollars they get, it puts it in a much better perspective. | 5b4649fa-fad8-4144-ac06-d07f1b6ff15c |
5tw0me | What's it called when you have a memory of hearing something while looking at another source? | It's called associative memory. Any time you're remembering things, there's a whole lot of other potential activations than what you recall. Sometimes the connections are strong enough to pull a peripheral memory into full recall. | afe60fab-a301-4adb-af2c-5cc2dfcb4f69 |
7dp3t1 | Why do we feel the need to use hand motions when talking even over the phone when the other person can’t hear us? | The real question is why we bother to talk on the phone in the first place when the other person can't hear us. | 96706e26-eb01-4296-88f5-561d4a66fbde |
3is5ts | Why does it hurt if I drink through the nose? | We didn't evolve to drink through our noses like for example elephants. We evolved to drink through our mouths. We smell and breath through our nose. Water getting in our noses implies to our body that we might be underwater and getting water inside us, so we might be in danger of drowning. So the unpleasant feeling of water in our nose acts like a warning and motivation like "avoid this happening, get out of these conditions", instinctively directing us away from the danger of drowning. | 4ab48e63-0360-47f3-ad64-21eb3fc1e123 |
61cm84 | Why are stocks worth anything? (particularly ones that don't pay dividend) | As a shareholder you are a part owner of the company and are entitled to what an owner would be entitled to(profits from the company). In the short term the company may not have profits, or wants to grow the business so the Board of Directors(elected by the Shareholders)decides to reinvest the profits instead. In the long term, the goal whether you're .00001% owner or 100% owner is to grow the company to a degree that you can pocket the profit. Also the shares themselves change value. As late as 2001 you could Apple shares for under 15 bucks. By 2011 they were over 400 dollars a share. A 40,000 dollar investment back then would make you a millionaire just in the value of the shares not to mention the 17,000 plus a year you'd be collecting in dividends. They've since done a stock split so their share price is much lower, but you'd have more of them. | ca3112f3-9b3f-4ef6-b5b4-1878d8ebd160 |
2aoa34 | Why isn't all internet data encrypted? | Encryption adds overhead, notably CPU time in encrypting/decrypting the payload and the accompanying latency of doing so. The vast majority of traffic gains no benefits from being encrypted, so it would be a waste of time and resources. | 10cf7ca4-d7a8-4020-afd7-d9ab31a3fbc1 |
5wb8pw | How does vector and matrix operations differs in CPU vs GPU? | Most modern CPUs have vector units, so they do not differ from GPUs in any meaningful way.
Intel's x86 family of microprocessors initially supported IEEE scalar floating point arithmetic with the x87 family of coprocessors. This architecture was integrated into the CPU starting with the 80486, providing a separate register stack of 8x64-bit (80-bit internal) registers usable only by the FPU.
In 1997, Intel introduced the MMX instruction set. The MMX instruction set used the same register stack as the x87 FPU, but used the register stack for vector integer and vector logical operations. The base x86 instruction set supports only scalar integer and scalar vector operations on the CPU's general purpose registers.
In 1999, Intel introduced the Streaming SIMD Extensions (SSE) instruction set. The SSE instruction set extended the register stack used by x87 and SSE to 128 bits and added even more vector integer and vector logical operations.
In 2001, Intel introduced the SSE2 instruction set. SSE2 is intended to fully replace MMX and x87 (although x87 computes to a higher precision as it uses 80-bits rather than only 64).
When AMD introduced the x86_64 microarchitecture, SSE2 was adopted as a standard component. Furthermore, the number of registers in the SSE stack was doubled from 8x 128-bit registers to 16x 128-bit registers.
Subsequent instruction set extensions including SSE3, SSSE3, and SSE4.x were introduced over the years.
In 2011, Intel introduced the Advanced Vector Extensions (AVX) instruction set which greatly simplified vector instructions for reasons that aren't germane to this post. This instruction set expanded the vector registers from 128 bits to 256 bits. AVX extended vector integer and vector logical instructions to 256 bits.
In 2013, Intel introduced the AVX2 instruction set which extends floating point instructions to 256 bits.
A 512 bit version of AVX2 is available on Intel's Xeon Phi coprocessor.
Intel's architecture uses the same hardware to execute scalar and vector floating point operations. That is, scalar floating point operations are performed on the vector FPU hardware. This is not true for scalar integer and scalar logical operations; there are multiple scalar integer ALUs per core in addition to vector integer ALUs and vector logical ALUs.
The vector portion of Intel's CPUs is remarkably similar to that found in a GPU, with a few key differences.
1. The instructions driving the CPU's vector extensions are all proper x86 instructions and are executed on the CPU. No special setup, driver, or runtime is needed for a program to invoke them. However, the operating system does need to be aware of the instruction set to ensure that it will save the registers during context switches.
2. Memory is loaded into the vector registers in the same way that it is loaded into the general purpose registers; same for storing.
3. The CPU's vector extensions run at the CPU's clock speed and are a part of the CPU's pipeline.
From an efficiency perspective, there is virtually no overhead involved in setting up vector arithmetic on Intel's CPUs. There is however overhead involved in setting up vector arithmetic on any GPU. However, GPUs have a massive number of vector units and for particularly large and parallelizable working sets the overhead will quickly be overcome by the sheer amount of throughput.
For any non-parallelizable working set, the CPU will usually be the best option.
For a small parallelizable working set, the CPU will usually be the best option.
For a large parallelizable working set, the GPU will usually be the best option. | b0c53784-73c3-4256-be00-895d1a95a17c |
3texw5 | What is with the fighting culture in hockey? | Your question's a little vague.
If you're asking why do people like watching people fight in hockey, it's because it's entertaining in the same way that mixed martial arts cage fighting events and boxing are entertaining. People get a kick out of people kicking the shit out of each other, even if that's not the prime purpose of the sport.
If you're asking why there's fighting at all in hockey, it's because it's a violent sport that requires strength and endurance to play at the professional level and is extremely competitive and makes players' blood run hot. If you're gonna play and win, one of your team's weapons is intimidation, and one of your own team members beating the hell out of some member of the other team is one way to either put them in their place or let them know you're not gonna be pushovers yourselves. | f086aca7-5b7f-4de4-9c4d-636da49d45ff |
8qmqtm | had a shower thought...why do the drawings you put in fogged glass stay there even after a session of defogging and into the reformed glass? | The oils on your finger stick to the glass and less water vapor will stick to the oily sections of the glass when you re-fog it. | e959a95b-e36d-44f3-8730-a138322b9b2f |
3h32kw | [NSFW]Does the Quran really say this? If not, how is it being interpreted by ISIS? | Islam has a concept which is often translated to english as "slaves" and other times as "servant" because it really has a meaning inbetween those 2 words.
This servant does not have his own freedom, and is in that way comparable to a slave to some degree. But at the same time he is made a part of the family. The prophet Muhammad commanded muslims to treat them well. To feed them and clothe them the same way that you feed and clothe yourself. And to not hit them. And to not put them to hard work unless you help yourself. So there is a very big difference from how we in the West understand the word slave. I will quote some sayings from the prophet regarding this below. Many slaves held very important jobs with a lot of power and responsibility (so not just manual work).
Islam generally forbids all sexual relations between people except between a man and his wife. However, since a female "servant/slave" also lives in the same house as the owner and is under his guardianship there is a verse in the Quran which seems to allow sexual relations between the female slave and the male owner. The exact interpretation differ. Some say it is if they get married and others that it is allowed even without marriage. But it is an allowance for them to have voluntary sex with each other. it is not a permission for rape (since this would be like beating and worse which is not allowed). From what I know there is agreement that if she gets pregnant she is a free woman and is treated that way, and the child is recognised by the father (in fact many caliphs during islamic history were sons of such a slave woman but were made heir to the throne by their father).
Islam also puts huge emphasis on it being a good deed to give slaves their freedom and it is very, very recommended. Many muslims believe that the islamic rules would naturally lead to slavery disappearing over time, but that it was impossible to simply abolish it from one day to another since this could cause the society to collapse since it was dependent on the institution (anyone who wants to see how impossible it is to abolish slavery from one day to another can watch Game of Thrones where Daenarys tries to do this and it goes wrong). Many muslims also sees it as rules which were used in specific times - for instance after a war - where you would have many children and female widows with no man to protect them from other men. These women and children would then get a guardian who had to feed and clothe them, but who instead had the right to tell them to help with work etc. It is the opinion of many scholars if not all scholars that slavery is no longer allowed since all the people that used to be slaves have been set free and it is not allowed to make new people into slaves.
ISIS have reached opposite conclusions than all islamic scholars. They ignore the prophets command to treat the slaves well and instead allow rape. In their sick mind the permission to have sex with them is the same as permission to rape. Apparently they do not know the difference.
Here are some of the quoted from the prophet:
"The Prophet, peace and blessings be upon him, enjoined good treatment of slaves and he would say, “Feed them from the same food you eat and clothe them from the same clothes you wear, and do not torture the creation of Allah the Exalted.”
Source: Al-Adab Al-Mufrad 188
Narrated Al-Ma'rur: At Ar-Rabadha I met Abu Dhar who was wearing a cloak, and his slave, too, was wearing a similar one. I asked about the reason for it. He replied, "I abused a person by calling his mother with bad names." The Prophet said to me, 'O Abu Dhar! Did you abuse him by calling his mother with bad names You still have some characteristics of ignorance. Your slaves are your brothers and Allah has put them under your command. So whoever has a brother under his command should feed him of what he eats and dress him of what he wears. Do not ask them (slaves) to do things beyond their capacity (power) and if you do so, then help them.' "
— Sahih al-Bukhari, 1:2:30 | 934e3de6-24c1-47a8-8231-1b2c795bf593 |
1nrq1n | What makes computer hacking difficult, and not something a computer itself does? | Well in some cases, it does. But that's another story.
Consider what computers do: very simple tasks, *very* fast. They don't (usually) screw up.
Now hacking consists, fundamentally, of finding cases where people told the computer to do the wrong thing. At a very basic level, this is a deviation from expected behavior, which makes it...unpredictable. Computers suck at it because it's a *difficult* problem that can't easily be broken down into simple problems.
Or in a nutshell, it is very hard to predict the unpredictable. | 963e819a-fef7-433e-926d-b0b423932537 |
4utamu | Why do some biscuits take longer to completely soak if completely covered by liquids instead of slowly dunked? | When you dunk the biscuit, the tea replaces the air inside the biscuit. The air has to be able to escape the biscuit for this to happen. This is easy if part of the biscuit is still dry, because the surface is porous. But when you completely dunk the biscuit the porous surface is covered by tea, which resists the passage of air. Try putting a handkerchief up top your lips and blowing through it. Then try it with a sopping wet handkerchief, and you'll see the difference. | e9059cb8-d3b2-4ec9-b4dc-c7272fc5c5df |
2lo1jq | What is a Jehovah's witness? What's that all about? | EDIT: [suns36orange](_URL_0_) has graciously provided links to actual material generated by the Jehovah's Witnesses and can answer questions from the perspective of someone who actively believes. I honestly don't and I was a child at the time I was so my views are coloured in that regard.
Former JW: They're another sect of Christianity which believes that everyone else got it wrong. Main things I remember from my early childhood include a lot of meetings at the Kingdom Hall (church). They believe there are only ~~444,000~~ 144,000 going to heaven and everyone else gets to live on super Earth after the apocalypse and a 1000 year reign of Satan. After which Satan gets destroyed for good (right now he's just locked up). No holiday celebrations of any kind except Passover and wedding anniversaries. I was told this was worship of things that were either evil or not God. No flag worship (national anthems, saluting the flag), and everyone's favourite, proselytize actively to try and save as many people as possible. Yes we all knew we were annoying, but God told us to. Most of the time I got the sense that everyone had better things to be doing. Good thing to know, once you're out, you're out. Disfellowship is what it's called. So a good catch all to get them off your doorstep is to just tell them you've been disfellowed. You're kinda allowed to go back to church if you choose, but you're in a back room away from everyone else and they can't associate with you.
Wittness congregations range from super liberal to super conservative. I was lucky enough to grow up in a fairly liberal one. Other people will have horror stories relating to abuse and segregating yourself from the community. Elders are the leaders of the congregations. I have no idea how they are picked other than they are old and male. The Watchtower Society is the main office and distributes all the literature they stuff into your doorjam when you're not at home or don't answer the door. They're a crazy bunch of money grubbers so far as I've read into them. They've predicted the end of the world a few times and failed. They've lived lavish lives off the tithe that members must give (I don't recall how much). | 75462937-84dd-4884-9ee0-242eae8c768c |
1vb2gg | How do us humans know how to have sex? | If nothing else, experimentation with sticking one thing into another and having it feel good. A penis and a vagina are located in the same general region and probably wouldn't be difficult to figure out that one fits the other pretty well.
No contact with any other human being would likely also come with no stigmas attached to such experimentation. | b2f5c899-b733-48ce-8fdb-d34a92199510 |
2fwtlx | Why, if I live in Jackson, MS, my Amazon package went from South Carolina to North Carolina (the opposite direction). | Not if it had to have it's own truck to do so. Most of the carriers use a "star and connector" model for delivery. For a long time, every fedex package that left it's "region" was routed through TN because this simplified logistics and made economic sense. Increased volume has allowed for more local replications of this model, but...the same principle is used. It's better to have full trucks and planes then empty ones even if it means transporting a given package the long way. | 34d06b4b-81b9-4f20-9538-24c3ec4f929e |
3gjyzl | Why don't cars sound like the explosions in their engines? | As others have said, insulation plays a great role - an explosion in a sealed box is not going to cause much displacement out of the box.
However, there's another factor. Explosions are discrete when you have spaces between them. But what if they are really close together? A car going past you might have an engine running at 2000-4000 rpm - which is more like 33-66 rotations per second. It's kind of complicated but each rotation of the engine fires multiple cylinders - maybe 2 or 3 depending on engine type. So we're now talking about 100-200 explosions per second. This means that the explosions of the exhaust are vibrating the air at 100-200Hz (Hz=cycles per second).
These frequencies are right in the range of human speech - 85-180Hz for males, 165-255Hz for females. It explains quite clearly why an engine could have a "Haaaa" sound - the detonations of the engine are pretty much at the same frequency as a person humming.
This is quite remarkable - that the physics of an internal combustion engine would happen to provide for detonation at the same frequency as a human voice. Depending on how the physics of engines turned out it could easily have been super low (10s of Hz) to super high (1000s of Hz) where a toddler could not make a "Brrrr" sound to imitate a running car - he/she would simply be unable to reproduce the sound. Needless to say, future toddlers might make no sound at all when playing with their toys since cars are rapidly turning electric and therefore nearly silent. | 539b4e45-6dfa-4bff-850b-5417ae2bf843 |
4t956t | How is online shopping safe? | For example, when I buy something online, the online shop uses my card details and uses that to take money from my bank account. So why can't they just randomly take large sums of money from my bank account? Is it all just based on trust? The bank account doesn't know any difference between "The customer just bought $5 of stuff, transfer the money to me" and "The customer just bought $2,000 of stuff, transfer the money to me". The vendor can easily fake large orders like this. | 1232a692-922f-4bd5-b602-b9073912667f |
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