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ci68e7 | How do people like firefighters/exterminators determine the “origin” of a fire/infestation? | Firefighter since 2008 here.
Most places don't burn to the ground with nothing but ashes left.
Finding the origin consists of viewing how far along things burn and understanding a fires normal path. Fire burns up and out, with a goal of getting more air to feed itself. In this way there is often a V where the about lowest point in the fire damage has some of the most thorough burning done to it is the likely spot where a fire had started. Then you look at what was in that area that may have been able to start a fire, like a candle, or a hair straightener, or electrical wiring, space heater, etc.
That's the simplified version of how it's done. Many get more complicated than this, but that and some experience in looking at fires is the normal method of finding the origin most of the time. | caeadbf9-bec4-491d-a32b-16cd6d926b5d |
ci69iy | How can anime be produced on a weekly basis? | They work on multiple episodes at the same time, and the they work probably at least 50 hours a week to meet the dead line, and sometimes they don't, so the episode will take a dive in quality.
Edit: to the pay question, animators get paid like garbage. Also for other shows like dr.stone, that was in production probably half a year before it aired, so they had a long long time to get it polished. | b751acc5-4223-4a0d-b1d7-e3fdc821ca6a |
ci6b0z | What are the technological and economic implications of T-Mobile—Sprint merger? | Technological- T-Mobile will gain a lot of “midband” spectrum— airwaves that carry data not as far but can carry a ton of it. This will allow them to bolster their LTE network and build a relatively high capacity 5G network with ease.
Economical- 4 carriers down to 3 is bound to increase prices for customers in the long term. Look at Canadian cell prices, they have 3 major carriers.
Service quality should improve a bit, but it won’t happen overnight. | 265e11c1-0c6c-4c3d-8608-7b5d7ce705a3 |
ci6ip8 | What is the difference between a directory and a database? | Do you mean "directory" or "repository"?
A "directory" is basically a Windows folder. It's part of a filename, and it's used to group related files together.
A "database" is an actual file, which contains data organized in a structured way.
A "repository" is a Git term; a Git repository is basically a Git folder for all of your code, and it keeps track of when that code or file was put into the repository (a "commit") and by who.
What this is saying is that if you regularly add your database to a repository, it's difficult to lose because one of the functions of Git is to be able to revert back to older commits to a given repository; you can turn back the clock and restore your code to exactly as it was at that time... and if you have a database in that repository, the database is restored as well. | ea3a0818-d15f-4b58-b380-071b8b1db2b1 |
ci6qt5 | What purpose do continents serve apart from broad classification? | There is not one but a few different models for the continets. Some of them are just for classification. Some are used to differentiate what is one landmass and what is another. I thing the most common models used are the geopolitical and historic political one. These differentiate between what you could roughly call cultures. | a0444128-c5b3-46a6-86f2-bc470e4edc6a |
ci6w8y | what kind of effect would forgiving everyone’s student debt have on the economy | Easiest way to describe it is this.
Think of all the money that people are spending per month on their student loans. Many are spending hundreds per month to pay off their loans.
All those debts disapearing would be a big boost to the economy. People that are paying off their student loans are generally young, and all are working.
Forgiving those debts would mean an entire generation of people that now have enough money to buy a house or buy a car.
Its money that would get spent basically right away. And money changing hands means more economic activity. | 2db7be26-0372-483f-8a40-51810c442eea |
ci6wbv | What is the “mirror universe”, how Leah Broussard and her team trying to prove its existence/absence? | And another good question that I have asked in the past, that has since gone unanswered: Is there some reason to suspect that this "mirror universe" is fundamentally different to the CPT-inversion, or is it that the mirror universe is another fancy name for the CPT-inversion? | 73097fb0-9061-48e4-985c-34fc20ed8d2b |
ci7at1 | Does dyslexia only effect reading and writing, or visual input in general? Either way, how? | For me it does different things. It's not just reading or writing, because I find it difficult to read I require a good memory when things are explained. Because of this I can imagine and almost design something in my head with a CAD like 360° view. Not sure if everyone is the same
Here's the different types
"Primary dyslexia: This is the most common type of dyslexia, and is a dysfunction of, rather than damage to, the left side of the brain (cerebral cortex) and does not change with age. There is variability in the severity of the disability for Individuals with this type of dyslexia, and most who receive an appropriate educational intervention will be academically successful throughout their lives. Unfortunately there are others who continue to struggle significantly with reading, writing and spelling throughout their adult lives. Primary dyslexia is passed in family lines through genes (hereditary) or through new genetic mutations and it is found more often in boys than in girls.
Secondary or developmental dyslexia: This type of dyslexia is caused by problems with brain development during the early stages of fetal development. Developmental dyslexia diminishes as the child matures. It is also more common in boys.
Trauma dyslexia: This type of dyslexia usually occurs after some form of brain trauma or injury to the area of the brain that controls reading and writing. It is rarely seen in today's school-age population."
_URL_1_
From what I understand its still an on going study but some research shows that it's to do with the different matters that the brain is made up of. That people with dyslexia often have a different make up to nondyslexic people.
This website explains more
_URL_0_
Sorry for the long post (mainly copy and paste)
I love being dyslexic, I think I see the world differently. I would never change it | 29426e1a-1d77-4e28-b0f8-22df57de3197 |
ci7ibi | Radioactive half life. | It is probabilistic. So if an atom has a half life of 1 second, this does not mean that in 1 second that atom will now be a half atom. Instead, it means that on average, that atom will decay within its 1s half life 50% of the time. | b09af9ae-e83c-48b8-9ed2-7d97941ff4c1 |
ci7zth | why are clouds substantially more flat on the bottom? | As warm air rises, the water vapour remains invisible until the air cools enough for it to condense into water droplets. The altitude where that happens marks the bottom of thecloud. | 058be940-a294-492e-8fab-0f2fbd3afdff |
ci8mad | Why do strongmen have more body fat & smaller muscles than bodybuilders but can lift heavier? | Power lifters focus on functional movements- the actual motions used to lift, push, and pull heavy items- to maximize the performance of the relevant muscles. Body builders focus on maximizing the size/appearance of many muscles that are superficially visible, but may not be relevant to the functional motion of lifting heavy. Body builders have to work hard to get their body fat so low, and often do so only for competitions before reverting back to a healthier percentage, while power lifters don't bother. | f743b3a6-48d8-461e-adaa-9dc1d90529a2 |
ci8ujt | How do baby animals developing in eggs eat/drink with nothing to eat/drink? | In eggs the baby uses the yolk for nutrients. In placental animals the mother provides nutrition through the umbilical cord. | 34874ff5-28de-4d52-ba6b-526b096a168a |
ci9euk | Repeatedly plucked hairs keep growing, and often get stronger/thicker, instead of going away. What is the mechanism behind this? How does the body not 'get the message' and learn to stop growing them? | Plucked hairs dont get thicker, its just that the tip of the hair is now blunt from being cut that it appears thicker.
And no, the root is embedded in the skin. | d8ae0610-08f5-416c-bc47-78058b99ac98 |
ci9nbe | why aren’t all rivers like the Grand Canyon? | First off, it's the Colorado River. But yeah, it's like that because there's so much water and it flows so quickly. It was flowing fast in the same place for a very long time, and the ground underneath is very carveable. Other rivers are either closer to the sea and spread out (so they aren't concentrated enough to carve), or weaker water sources without the power to do so. | 168b20c0-cd36-4b39-b9fd-0c3fa26d7849 |
ci9ph7 | What physically happens to the body when bungee jumping? | It falls down. Then it goes up. Then it falls down. Then it goes up. Then it falls down. Then it goes up. Then it falls down. Then it goes up. Then it falls down. Then it goes up. Then it falls down. Then it goes up. Then it falls down. Then it stops. | c309ccfc-ca6b-4da8-bc92-6d37d536c78d |
ci9w0w | What are the real ways to save the environment? | Don't have a pet which eats large amounts of meat in its diet, reduce your meat consumption, reduce your car mileage and airmiles; are steps you can make on a personal level to be more green. | 51f7be6b-190a-46f1-a65b-0aa5c500ea2b |
ciab9p | Beyond Meats Market Cap is 25% of the S & P. | Market cap, short for market capitalization is the total value of the company, based on what people are willing to pay for the shares. To put it another way, it’s the price of a share multiplied by the total number of shares that exist in the company.
The S & P is a list of 500 really large companies.
Taken literally, that statement therefore means that the total value of Beyond Meat is a quarter of the value of those 500 huge companies all added together.
HOWEVER
That’s not what was said.
[This CNBC article](_URL_0_) for example says that Beyond Meat is worth more than 25% of those companies. In other words, it’s around the 375th largest company on that list.
This is obviously a big deal for that company, and I’m not going to buy any shares, but I don’t see why it’s “ridiculous”. The share price of a company is based partly on its actual sales and assets, but also on its potential. People are guessing that it will make it really big. This is a gamble, but not completely out of the question. | a91e5048-16f6-4c34-85c9-cf819e883ee0 |
ciap26 | Why is it that sometimes we see the sun with rays shooting out of it, and other times we see just the orb-form of the sun? | It's our atmosphere. Here is my favorite [effect](_URL_0_). Light reflects of water and other particles depending on density and angle. | ab655de8-93cf-4507-b413-4832fbca6972 |
ciavpw | Why does the sun become easier to look at when its setting? | The simple answer is that it's not as bright when it's about to set and especially while it's setting. The reason it's not as bright is that the light from the sun is going through more of the Earth's atmosphere and so more of the light is being scattered by the air. | b0919674-4f4f-4230-ab6a-76a6557ffcc2 |
cibiwf | Did our ancestors experience vision loss similar to how we do? If so, how common was it and how did it affect their day-to-day survival? | Nearsightedness is largely a disease of urbanization and industrialization. populations like the Inuit went from like 0% nearsighted to like 50% nearsightedness in one generation due to urbanization. So our ancestors likely did not have that vision issue. But presbyopia, which is difficulty seeing near, starts around age 40 no matter the population, in most people. | e7af8b80-074c-452b-89a2-042011333d59 |
cibonq | How come a nearsighted person can see clearer when they squint? | Myopia is caused by an elongated eyeball or an over-curved cornea or lens. Basically, the geometry of the lens in relation to the retina is wrong.
Squinting can alter this geometry, "squishing" the cornea and lens into a shape that better focuses the incoming light on the retina. | aa611699-7b9b-446f-bda4-e946996dea11 |
cibpd7 | How do animals have a natural instinct? | Your thoughts and behaviors come from the patterns of neurons in your brain, like a very *very* complicated series of if/then triggers: IF you are hungry and IF you see bread and IF you smell bread THEN you should pick up the bread and eat it.
This happens as neurons fire and trigger neighboring neurons in unique patterns. Your empty stomach releases chemical signals that act on receptors in a special group of neurons. Those neurons fire and send their own electrical signals through your brain. Meanwhile, your eyes are sending signals to the neurons that help you recognize what you're looking at. They send a signal out that says "bread". This "bread recognized" signal hits the "what is food?" neurons which fires off. That signal and the "I'm hungry" signals meet in another part that only fires if "food is seen" and "I'm hungry" signals hit it together. That sends off *another* signal and I hope you can see where it's going.
In humans, most of those patterns are learned. Over and over as a baby you see bread and your eyes send that unique pattern to your brain, which creates a unique pattern of neurons firing. Over and over that pattern shoots out through your brain and triggers a bunch of things. At the same time, your parents are feeding you the bread so among all of the random noise those two unique patterns bounce back and forth - see bread, eat food, see bread, eat food. They strengthen each other so they stick out above the noise, and your brain prunes the other, weaker signals so that there's less noise and eventually that pattern of neurons firing together locks in: when "bread" fires, "food" will also fire, because that's the pattern that you made.
Your DNA is already perfectly capable of coding incredibly complex instructions to build the rest of your body. There is very intricate machinery inside of you that your cells build based on your DNA. And that includes some basic patterns in your brain, like "when carbon dioxide levels are high in the blood, send a signal to the lungs to breathe harder".
Hundreds of millions of years ago, mutations in DNA arose that led to simple nerve cells clumping together, and over time the mutations in DNA caused animals to build brains. More mutations led to specific patterns of cells in the brain, and the patterns that were beneficial for survival (like, "you should breathe") were passed on. Some of them became very complex, so that animals could be born with patterns already set in the brains that cause behavior like successful hunting for food. Among those patterns was a desire in humans to eat energy-rich carbohydrates.
Humans are born without a lot of instincts and are pretty helpless as babies because 1) the emergence of families and groups meant babies *could* be helpless and still survive with care from adults, 2) language allowed information to be passed to new generations without the need to put it into our DNA, 3) increased availability of nutrition from cooking our food meant we could afford big, smart, flexible, but also very hungry brains, that 4) are already almost too big to fit out of the birth canal so if we stayed in the womb any longer to build the patterns before birth we wouldn't fit at all. | fd1b0853-006f-4dd7-bb01-eeb8ec05e980 |
cibsw4 | how WhatsApp prevents spammers from using the app | Their main tactic is really just making it difficult to sign up for a WhatsApp account.
To sign up for WhatsApp, you need to put in a real cellphone number. They have a way of telling a real phone number from a "virtual" one (using VoIP), and block any attempts to sign up with one. By doing this the barrier to entry is high enough that scammers don't bother with WhatsApp and just use platforms that are easier to access. | 218341b8-b66c-44c8-a503-22af25f239d6 |
cid0sn | why is it that our hands feel the cold faster than the rest of our body? | The body works hard all the time to keep your body at the right temperature. Most important to keep warm is the core of your body—internal organs and brains. If you’re in a situation where it’s cold and your body starts to get cold, it will constrict the blood vessels at your extremities—hands and feet, arms and legs—so that there is less blood flow to the extremities. That way, the body works to keep your core warm while sacrificing the warmth of your extremities. It doesn’t have to keep warming up blood that has flowed near the extremities. The reason the extremities make your blood colder is that a lot of that blood is nearer the surface and is not as insulated. | 5958409d-ad56-4ddb-9e37-88d736519fd2 |
cid2uv | how are tasting notes manipulated? | Basically it's all manipulated by adding stuff. For wine/whiskey/beer etc the ingredients used from the amount and type of sugar, type of grapes, hops, barley, acids, artificial flavorings, etc. How long it aged in casks, type of wood, etc.
Black coffee is an exception, it's the most complex beverage. No one understands it exactly how the various flavors notes happen. But the parameters are terrior aka type of soil including what nutrients are available, elevation, sun or shade, how its processes after harvesting ie wet process or dry natural or honey process. Then the roasting, how long its roasted for how fast the temp changes, etc etc, and finally the method of preparation ie grind size, water temp, extraction.
For flavored coffees, it's all artificial flavoring. | d74959a4-89bf-45b3-8c95-d12f4ab9a7ee |
cid4d3 | How is water consumed differently to food? | Water is absorbed by the small intestine, and the water inside what you eat gets also absorbed there. Then, the solid matter goes through your large intestine, where the proteins, vitamins and minerals are absorbed. | 1c61f082-a479-4d9c-a3ab-e26b354c206e |
cidkn5 | Why did my head hurt like hell after blowing my nose while holding it closed on a plane. | Usually this happens when your sinuses are blocked in some way. As you ascend, the air pressure decreases in your sinuses. When you start to come back down, it starts to rise and gets trapped in your sinuses causing pressure and eye watering "omg am I having a stroke" levels of pain.
You can avoid this by using a decongestant spray before flying. | 417c11d3-bc09-4b90-b676-1974679ebf8f |
cidnkc | Stocks | Say there are 100 stocks in Apple. If you buy one, you own 1% of the company. Then say Apple makes a new iPhone that is insanely popular. They double their profit this year. That means the company is worth twice as much as when you bought it. It also means that 1% of the company is worth twice as much as when you bought it. Someone else would be willing to give you twice as much money as when you first bought it for this reason.
So the value comes from owning a growing business. If the business doubles in size because they have doubled sales, the value of each stock also doubles. But if the value of the business drops, so does the value of each stock. | 8bc38b85-8a5f-4216-9a98-ac77f267fe53 |
cidrwv | When driving a car with an open window at certain speed, why there's a noisy sound in the ear like pulsating or drum ? | If you take a bottle of water, remove the cap, and then tip it upside down the water will flow out in a gurgle. Every so often the flow will stop and air will get sucked up into the bottle, then the water flows again. This happens because of pressure inside the bottle versus outside.
If you poke a hole in the upper part of the water bottle, this stops. That's because one hole lets air in while the other lets water out.
That's what's happening in your car. If you only open one window, air is forced into the car due to the speed, but that builds up pressure until the air forces its way out, and then the outside air is forced in again. That back-and-forth in pressure is what you are hearing/feeling.
If you open a second window at the back of the vehicle, the air flows in one window and out the other, like the hole in the water bottle. | ab0c0869-dee0-4b83-883a-069aab289ea7 |
cie1zo | FAT32, exFAT, and NTFS: what’s the difference, why does it matter, and why does the size of the drive limit formatting choices? | Tl;Dr: they are the same but allow slightly different maximum sizes for hard drive partitions.
Full spiel: all memory is kept in paired bits of hexadecimal code. This code is the arranged into a grid, or table. A part of this table is the address table/lookup table (there are a few other names for this table too). This table is usually kept at the very beginning of the entire partition (section of hard drive), and sometimes at the end too.
FAT32 - FAT stands for file allocation table (remember the address table?), the 32 simple means that data is stored in 32 bit chunks. This is the most common by today's standards and FAT was developed originally for Windows systems, but is in common use in many, many systems today. Files are allowed to be a max of 4gb in size and smaller files have a minimum size (called cluster size in FAT) of about 16kb. The maximum partition size of FAT32 is 8gb.
NTFS - NT files system is Windows newer default system for memory allocation. It supports security permissions (file permissions, read and write or write protection), change journals (records of actions performed), shadow backups, encryption, quota limits and a few other things I will gloss over. There is no file size limit and no partition limit (at least not realistic ones). Where this file system lacks is in compatibility, very few systems other than windows can read and write to NTFS drives. Xbox one can, but earlier Xbox models cannot, PlayStations cannot, macs cannot; with Linux your mileage may vary.
ExFAT - extend FAT is another Windows designed system, it is build with size in mind. As with NTFS, it has large limits on its file and partition sizes. ExFAT is much more compatible than NTFS, macs offer read and wrote support, many Linux systems have add ons to read and write to it. It's only really big disadvantage is a lack of support for journaling, or logging changes to the state of the drive. All told, this is probably *my* preferred format, for now. | 1ab3756b-c609-4c07-86d1-d95374c908db |
cieshw | Why are the principles behind dieting such a mystery? | They aren't. It's literally math.
If you burn more calories than you consume, you lose weight, regardless of the composition of your diet, period. It's been proven repeatedly and is an extremely basic concept.
(ex., [_URL_0_](_URL_0_))
The only "mystery" is that TDEE differs from person-to-person. If you're gaining fat, it's because your estimate of how many calories your body is burning day-to-day is wrong, and you're eating above it. That's it.
Any stupid shit you see about "WELL WHAT MATTERS IS THE QUALITY OF THE FOOD NOT THE QUANTITY LOL" is people who don't understand that foods considered "higher quality" are also less calorically dense and result in a lower caloric intake. Every study *controlled for caloric intake* and comparing macronutrient ratios reports the same.
Any stupid shit you see about "reducing calorie intake might not actually help you lose weight!!!" is referring to hormonal shifts that cause people to have higher appetites when their ghrelin/leptin/etc responds to the change in intake, or trying to touch on social aspects of it, and are *not calorie controlled studies,* it does not mean that reduced caloric intake doesn't actually reduce body fat over extended periods of time. I promise if I lock you in a fucking room and only feed you three baked skinless chicken breasts and a cup of broccoli with each every day, you will lose weight regardless of what your hormones are doing, because you will be eating under your TDEE/BMR.
Any stupid shit you see about "starvation mode" is people who don't understand how resilient the human body is and applying their poor understanding of an emergency physiological fat retention process that doesn't happen for a *long* period of legitimate starvation to "lol I cut my calories by 250" and thinking it's why people aren't usually seeing weight loss after two weeks, despite one pound of fat being roughly equivalent to a 3500 calorie energy store. (The actual number is anywhere between 3400-3700, 3500 is just a safe bet.)
Just count your calories and don't give in to the increased desire to eat more when you do. It's not a mystery. | c685d9c1-511e-4ae3-a675-2da203a36b4c |
ciev5s | Why can my brain recognise four objects without counting, whereas if there are five objects, I have to split them into a three and a two? | This is called "subitizing" and is actually really cool. Basically, they're two different processes. Counting is a very manual deliberate and conscious process. Subitizing is based on your brain's object tracking systems--how many moving objects you can keep track of at once. Even if the objects aren't moving, your brain is using that same process of "these are things I want to focus on and keep track of".
You can also increase the number of objects you can immediately identify with training. Video games are one good way, but 6 is probably the upper limit | 8980acfd-a741-4b03-b079-00a2b4e330a8 |
ciez30 | How do stabilisers work? | There is a small sensor built into the device that detects movement - similar to the one on your phone that detects tilt.
The system is then setup so that when the sensor detects some movement, the motors offset it by moving in the opposite way.
Obviously there is a limit to this, as the motors can only move so much in any one direction, to counteract this the system is designed to detect different types of movement and react accordingly - so short, sharp movements can be counteracted completely, while long movements (such as panning a camera) can be detected and dealt with appropriately - such as countering vertical movement but not horizontal, or just smoothing out the bumps in the movement.
If you were to drop a stabilised device, it can often go as far as to detect it had been dropped, and park all of the moving components in a safe way so add to limit damage. | 82e4358c-46a4-4645-b3ab-e03216e81f75 |
cif01p | how does hacking work? | It depends what you mean by hacking. But there are various ways that someone can do it. For example, it's very easy to send an email which appears to come from, well, whoever you want. So I could send you (and millions of other people, cos I buy a list of email addresses) an email which appears to come from Amazon, saying that there's a problem with your account and you need to click < this > link to login and reset your password. Only the link doesn't lead to the real Amazon website, but to a fake copy of their login page that I made. So when you log in, you've now typed your password into a web page that I control. I now have your Amazon password, so I can log into the real site, change your shipping address, and buy stuff. This fake-website thing is called phishing.
Here's another method. Imagine you're Amazon (the real one this time). The first page of your website asks people to log in, so they type their username and password into the boxes. Let's say you type in uuu and ppp. To find out whether those details are correct, the web site checks its database of usernames and passwords. The basic logic of the database query would be "count all the entries where the username is uuu and the password is ppp". If the number of matches is precisely 1, then the system knows who you are, and regards you as having logged in.
Now, imagine that, instead of typing in ppp as your password, you type "ppp, or 2+2=4". As before, Amazon takes the username and password from the boxes you typed, passes those values to the database, and uses them to complete a query. The query now looks like "count all the entries where the username is uuu and the password is ppp, or 2+2=4". And you know what? Even if the username and password are wrong, the number of matches is 1, because 2 + 2 does indeed equal 4. So the system regards you as having successfully logged in!
This is called a database injection attack, because you're injecting new commands into the database query. It's why you're not allowed to include "+" symbols in your passwords. (OK so it's a bit more complex than that, but this is ELI5. You get the idea.)
Now, imagine what happens if, as the password, someone types "ppp, and please show me the database of usernames and passwords". Yup, the hacker now has the whole database. Just because the programmer who wrote the login system didn't understand something called input sanitization, which means checking that people don't include valid database commands as part of their username or password. | bc666c03-af42-42ca-9efb-8c0d676d1a1e |
cif2w4 | When we listen to a song for the very first time. Some of them sounds wicked and eventually you get sick of it in no time. But some of them are not great at first, but it will grow on you and you enjoy them for longer periods? | Simple songs, with basic, repetitive passages are very easy to listen to - without any preparation you can easily pick out the full compliment of instruments and follow along. So a song immediately sounds good and exciting.
The problem is that such a song is pretty simple, so once you have listened to it a few times you have easily memorised it and it gets a bit boring.
The opposite end of the scale is a song with many layers of music and instrumentation - when you initially listen you will only pick up on the obvious instruments on the surface, which on their own sounds relatively poor. On repeated listens, once you have learned the obvious parts, you start to notice the additional layers hidden below - so the guitar is bland on its own, but when you add in a secondary melody from a less obvious instrument, they work together to create an overall better sound. It just takes multiple listens to allow your brain to notice all of the different layers and how they interact, as everything at once is too overwhelming.
Because the song is more complex, it takes more listens to understand it musically, but this extra complexity also means that it is more interesting, and there is more to gain from repeated listening and finding new details and interactions in the future.
S lot of this is subconscious of course - all we know is that AC/DC songs are lots and fun, but perhaps not as interesting long term as some weird Radiohead song... (Though your choice in band references may vary for obvious reason) | 541cc6e4-f54d-47b6-a017-93517c6ca66f |
cifeeq | What is the difference between state and province ? | A federated state and a province are interchangeable terms. They have more specific names in some places, e.g. oblasts, emirates, etc. In much of the world the term state is usually used to refer to sovereign states unless directly talking about the US. | 4d3a8b55-d272-462f-b0d1-d82e5135f978 |
cig0xb | How is community college different from normal college? Like... did the community pool money together to build that college or something? Sorry, I am not American. | They're 2 yr colleges and you either get an Associates degree and transfer or stop after that or skip that degree and transfer to a state college or university. You can also go for certain certificates.
They get more government funding than other schools so tuition is a fraction of what it can be vs. a 4 yr college. No, the community does gather money, the state does that with our taxes. | 3253aa6a-0d11-4f48-adfa-a40d1bfe09ae |
cig1l0 | What is the difference between normal light and lasers? | Lasers are produced by exciting atoms or molecules and stimulating them to produce light. The major difference between normal light sources and lasers is coherence. Which is essentially how similar two waves are.
Waves have two properties that are important here, the wavelength (colour of light ) and the phase which is essentially where in the wave the start is. I.e does it start as a peak, a low point or somewhere in between.
A normal lightbulb emits light which is not very coherent, there are many different wavelengths of light and most of the waves are not in phase with any other. Lasers however produce light all of the same colour and as a result of how that light is produced it will also mostly be in phase with each other. This property means that the light is temporally coherent. | e48058b9-8430-4f92-b900-2a92d2b74716 |
cigdwo | Why do smartphone manufacturers make telephoto lens but put less megapixels? | A traditional physical zoom actually does refocus the camera lens and it makes the same quality picture regardless if you are at 1x or 4x zoom.
Digital zoom is *not* actual zoom. It basically just crops the picture you have and zooms in on it like you can do with MS Paint.
So the more you zoom in digitally, the less picture quality you have. | cca13666-72c3-4c3c-8251-c2b05aea0828 |
cigpxa | Why is it harder to learn things as an old person? | you know what, it really isn’t. I’m getting close to 50 and in the last couple of years i’ve taught myself fairly passable German from the Internet, I’ve recently learned how to sail and repair a sailboat, i learned how to rebuild my car’s brakes, and also how to fix many parts of a specific type of vintage watch. 10 years ago I couldn’t raise plants for shit, now i have a cool garden and know a lot about landscape plants. I am not the world’s greatest crack shot but I learned how to shoot a pistol. I learned how to tile a kitchen wall, how to clip a horse’s coat, the list goes on. Learning new stuff is my favorite hobby— and this is not unusual for old folx, there are lots of constant learners like me out there.
I think the thing is: very young children *have nothing else to do*. Wouldn’t you learn faster if you had no job, your food was made and fed to you, your clothes were bought and given to you, you were driven everywhere and never had to look after anyone else? i’d hope so. Learning is kids’ ONE JOB. compared to them, for sure it *appears* as if older folks can’t learn. but that’s like saying birds can’t fly, just because rockets exist.
I bet the people who say “aw i can’t learn, I’m too old” were never so great at learning even when they were young. | 76f47036-b391-423c-b024-28aca8bbc16e |
ciha6a | What is the difference between adrenaline and noradrenaline? | Two different neurotransmitters which signal in different way. Noradrenaline doesn’t have a direct action on the heart. Instead it increases vascular tone. Also, adrenaline has a methyl group on it! | f1abf5d0-58a4-4633-bd70-df1eade4b763 |
cii0ah | Why can we sometimes feel our pulse in parts of our body and other times not? | Now if you can **hear** your pulse in your ear, mention that to your doctor. It's not typically worth an appointment on its own, but they'll want to know. | 5f6a386b-451f-4900-939e-fb72ccf16a34 |
cii1du | why a BIOS update is so much slower than copying a 16MB file | The bios isn't just stored on disk. It's stored in a special kind of memory that retains its data even when the power goes off. This memory requires special instructions to update, and it's usually updated one word at a time, rather than in blocks via direct memory controllers.
Since the operation isn't "undo"able, there is a lot of checking that you have the right data and all the data is ready before the operation starts. | edaf3e3c-2f43-4567-ba72-b562c8047506 |
cii7gs | I just learned that having 6 fingers is the dominant trait and having 5 fingers is recessive. If that’s so, why don’t more humans have 6 fingers rather than 5? | Dominant trait doesn't mean common. It just means that it tends to express itself whenever it is present.
On an anthropological level, if 6-fingered people were more highly preferred that 5-fingered ones, then the vast majority of the population would have it, but apparently humanity didn't find it a desirable trait.
Edit: Used 'than' instead of 'then'. It's been fixed. | d331e555-a8cc-4de9-ba0b-2bc1a49c5355 |
cii85f | why is the color green the only one that is used to edit backgrounds/things in movies? Why can't other colors be used? | When more movies were shot on film, they used to use blue more commonly. This process is called "keying" and it involved a chemical treatment to the film to remove that specific color.
The green you see today is called "Digi Green", and it's color matched to the small green filters inside camera sensors to give as clear and vibrant of a green as possible to aid in the digital removal of that green.
But depending on the real elements in the scene, they may use Digi Blue, or the older colors called Chroma Blue and Chroma Green - which were color matched to the color filters in the film emulsion.
Today, since all these effects are digital, you can also " key " out by any color, a range of color, or even by brightness. | d6cc3912-596b-4577-a826-317b57ae660b |
ciif0s | What exactly is sedition? | It is actions that openly go against the crown/state, similar but not quite the same as to what would be considered treasonous. | 58b6da93-cc13-40a0-a7a5-d8db03d43d65 |
ciij3i | How does the police obtain the position of a call without the phone having location turned on? | They use the signal strength of your phone between multiple phone masts and that helps them narrow bit down. Its also instant you don't need to keep someone on then line | cfbfd3a3-5fe4-45d4-9e6f-6d92e53ccede |
ciin1h | National debt | National debt is just like any other debt. When you want to spend more money than you have, you borrow it. Same goes for governments.
Why do investors/banks want to lend you money? Because they think you will pay the money back with interest. The more likely you are to pay, = the safer the debt, the lower the interest rate. Just like a bank might run a credit report on a customer, investors have ratings for government debt.
The very safest debt pays the least interest, but investors still what to loan money to safe borrowers because it balances the risk exposure in their debt portfolio. Often investors mix risky stock investments with safer government debt investments to balance their portfolio.
Countries like the US and UK are extremely safe. The US has never defaulted on its debt, ever, and so it can pay the least interest while countries that have debt problems, like Venezuela, pay a much higher interest rate if they pay you back at all. There is mixed bag with the Euro. Some Euro countries, like Germany, are super reliable but they also use the same currency as Greece, which has had some recent default problems. That makes it hard to isolate the risk in euro debts.
While all these countries owe a lot of money, it's not clear that paying the loans off is a good idea. It would be horrible news to all the investors, and retirement funds, that use this debt as a risk hedge. If retirements plans became a more risky investment, that would be **very bad**. In this way, a government having a lot of debt that it can afford to pay off at market rates, actually is good for the national economy.
The problem is that the borrowing is done by politicians, and they are sometimes short-sighted ignoramuses that do stupid stuff. That's not good for the national economy. | 377ce4e3-d003-4344-81af-5c394a488341 |
cij3ld | how are aromas created based on flavours we already created, such as “tiramisu flavour” without any of the real ingredients in it? | Chemical engineering. First they figure out which chemical(s) in the thing contribute to the flavour/aroma, then they synthesize those same chemicals in a lab from other materials. Voila | cb0793d6-f490-4783-99bb-e5a99a1bd050 |
cij63q | How do doctors reattache ripped parts of the body? | Microsurgery, using a microscope and very thin stitch material. | 36813545-a48d-4158-afdd-8519c9f34f7b |
cijbcw | The positive and/or negative effects of popping the neck long term | Nothing happens. It is simply gas escaping from your joints. A man cracked his joints for 50 years and nothing happened. | 72bf295f-dcda-4393-8eee-7757b5fc1b64 |
cijnac | Is the East Australian Current depiction in "Finding Nemo" film close to reality? | It’s the general idea, but much weaker, bigger, and less obvious, but the general idea of a current underwater is correct. | a051632e-98f2-4034-a6ee-d5ee235a289d |
cik4xy | How does a lightning 'find' the nearest spot on the ground? | Before you see the bolt strike, smaller "feeder" lines are either working up from the ground, or down from above. The first of these lines to reach a path to the ground becomes the basis for the bolt.
You can see it here:
_URL_0_ | 96cb11a1-93e6-4871-9cf7-a1d5242eb994 |
cikb9p | Where does the stereotypical image of an alien come from | In 1893, science fiction author H.G. Wells wrote "Man of the Year Million", where described humans becoming the stereotypical "grey alien". In 1901 he reused this description in First_Men_in_the_Moon. It's also the general description of the Martian evildoers in The_War_of_the_Worlds.
Wells was so popular, and influential, that the "grey" description became the norm in science fiction. | 5505b100-32a5-4edc-b544-ec886682896d |
cikscu | The gut microbiome and how dehydration affects it | To address the first half of your question: The gut microbiome describes the plethora of bacteria that live in your gut but do not harm you. In fact, many of them help you! (For example, you get almost all of your Vitamin K because bacteria in your gut produce it for you) The microbiome also helps prevent nasty bugs that cause illness from taking root: there simply isn't enough room!
The microbiome is still being studied, so honestly no one is really for sure yet which bugs are most beneficial. There are a lot of theories that the microbiome affects your overall lifetime health and things such as obesity. These are being studied, but we can't yet point to specific bacteria and say "this one helps prevent obesity." This is an area that will likely explode with new discoveries in the next decade or so!
Now, in terms of dehydration, I do not know of any specific effects. I did a cursory glace through medical journals and couldn't find anything. But I would not at all be surprised if it does impact the microbiome. So far, we have found that things such as childhood diet, bouts of diarrhea, and antibiotic use can all can impact the microbiome. | 4ee8b39a-1777-40e1-b1af-8e46a54b58db |
cikt5o | Why when you heat up vegetable oil, some waves start to appear on the bottom of it? | What I believe you're describing is technically called a mirage. If you've ever seen something incredibly hot, such as a jet engine, against a detailed background, you can see that the air around the hot object ripples. This comes from the immense heat of the object warming the air around it. This air becomes less dense, and rises. This means that hot air and colder air are swirling past eachother in a turbulent dance, and the place you're looking switches between more and less dense air. This difference in density bends light, which you see as a sort of shimmering or rippling. The same, more or less, happens in transparent (or near-transparent) oils on a hot burner. | 5cd3a1dc-0caf-4c60-9f08-d9e1c99c8a87 |
ciktqg | How does Advil/Ibuprofen affect your body after a night of drinking? | This isn't a "story." It is a well-documented interaction. The drug reduces inflammation in the body but has a common side effect which is increased risk of ulcers in the stomach because it prevents the formation of mucus (which protects the stomach from the acids in it).
Pair this with alcohol, which thins the blood, and you have a situation where you have higher risk for developing bleeding ulcers in the stomach and blood which clots less readily. Upper GI bleeds are no joke. | aa45babe-e189-44ca-bb4e-0a6df883bf65 |
cikuy6 | Why is the language of the Netherlands called "Dutch" and German not called "Dutch" since that is an Anglicization of "Deutsch", the German word for the German language? | The word deutsch (and dutch) originaly included both Dutch and german and the differences between german dialects were comparable to the difference between Dutch and german back then. Since England had more trade and contact with the Netherlands and flanders these were the Dutch they knew. When the german language started unifying they called that language (and eventually the country) by another name. | 09ed323a-bd2f-49ea-b3a2-bca0a689f769 |
cikzjg | Why does a car engine make a 'dripping sound' when you turn it off? | Metal expands and contracts with temperature. That's just hot parts cooling off, they make that sound as they settle back to their cold size and position. | 433fd328-2cde-43ce-93a4-8f6273e9da17 |
cil6uo | What would be legitimate uses for a shell company or shell companies and why would you need to use them? | Walt Disney used shell companies to buy up land for Walt Disney World in central Florida. Nobody really wanted that swamp land, so they knew they could buy it cheap as long as nobody knew Disney wanted it. If someone thought that one rich company wanted it all they could have got land in the middle of everything and charged a lot more. However, the different shell companies started buying up the land and it took a while before people realized who it was and jacked up prices. | d5370785-a08c-4724-8c16-11c102d6ced7 |
cil8wx | What happens to overstock of certain types of food/snack foods and unsold stock and how do shops/retailers keep it within local business/health and safety laws? | Given how long the dates are and now quickly they turn over stock and stores get new shipments, and the production cycles of such products, it’s easy enough to simply reduce or pause a delivery so as to prevent overstock and items approaching their expiration date. There are always channels like dollar stores as ways to dump close to expiration products as deep discounts. | 91a1bef0-b61a-4962-92e5-162c1a035d57 |
cilb7z | How do people in saunas withstand the extreme heat? | The sauna isn’t set to 300 degrees, that would kill you. Instead they built a sauna in a location that was extremely cold, so it was a 300-degree temperature differential between the outside temp and the sauna temp | 674f8ff5-cc9e-43d6-9ae0-b314fbea108d |
cile4l | For example, you read that the movie cost 50 million dollars, a that it made 100 million in domestic theatre and another 100 worldwide. Usually, who spend the money, and who earned the money? | Movie studios make it very difficult to find out exactly who is spending what and who is getting paid, it's called 'Hollywood Accounting'. Studios want to hide how profitable their movies are because if they made a deal with the actors or the writer to give them a share of the profits, you want to make it look like the movie didn't profit very much so that you don't have to pay anyone but yourself. It'll also effect how much you pay in taxes so it's better to say that of the $150 million dollars you profited, $70 million went to the marketing company (which you own) and another $50 million went to repaying your investors making the 'actual' profit of the film something like $30 million. | 079f74d1-fd9b-4df4-b5ba-cf6730fbd905 |
cim25i | Why does putting your tongue on a 9V battery hurt, but not when you touch the poles with your fingers? | The saliva on your tongue is a much better conductor than the dead skin cells on your finger; even if you make them wet, dead skin cells. The tongue also has more sense cells per unit area than almost any other part of the body. | e1c9bd89-6cbc-4e53-b3f9-72b529a255d4 |
cim2cy | Why do your ears kind of close when you yawn? | Yawning affects your eustachian tubes, which regulate pressure in your ear. The change in pressure hampers the passage of sound because it lessens your eardrums ability to vibrate while "hearing" | bc694bd0-6b0f-4810-a876-f38e20a7fe3d |
cimb2o | Why do phones have to be put on airplane mode when you're in flight? | Apparently the phones create a lot of "noise" for the plane's system and airplane mode "silences"your phone as it's not searching for a network and stuff | 278c51b9-78ef-4112-ab1e-56d412f75a6d |
cimfaz | why does a funnel breast develop on a fetus? | The "why" for genetic mutations isn't going to make you happy, they are mostly random. The term "funnel breast" isn't a very scientific one, but here's one alternative.
Pectus excavatum is the formal name for a chest deformity in which the sternum and rib cage are shaped abnormally. This produces a caved-in or sunken appearance of the chest. It can either be present at birth or develop after puberty.
It's a serious medical problem can impair cardiac and respiratory function and cause pain in the chest and back.
People with the condition may also experience severe negative psychosocial effects and avoid activities that expose the chest. | bde519bf-9031-447e-8593-b51301c9bf15 |
cimmzz | Why is Western classical music perceived as stimulating and good for brain development but not other music? | Pretty sure this was disproven a long time ago, and it was the fact that, at one point, babies who were exposed to classical music had attentive, educated parents and the class advantage that derives from coming from an educated and affluent family in western society. It’s all just cultural bias.
Just spend time with babies, talk to them a lot, and provide for them a stimulating environment (an aspect of which is just about any form of music). The time invested into babies and making them feel wanted, stimulated, and secure is what matters at that age, | 5053450f-f967-4889-9e5d-cab1cd2d097f |
cimowc | Why do some foods get hard when they go stale (ie bread) and some foods get soft (ie cereal)? | Because some foods have high water content like bread that dries up when it gets stale and therefore hard while others we prefer with low ater content and absorb humidity from the air and get soft when they are stale like cereal. | 3754e07d-b5d9-461b-be20-ad28388ae1b3 |
cin3qn | Why do some floors or steps get eroded by our feet, when roads don't visibly get eroded by tires? | Roads do get eroded by tires eventually (especially if used frequently or by heavy vehicles), you just don't notice it as much since you are traveling over them at high speeds. Roads are repaved due to erosion pretty frequently in some places. Also, your tires erode quicker than the driving surface (I assume because they are normally softer). | 12f2e565-2203-4859-995b-902c3aa6db26 |
cinde1 | Why do the same companies use different names? | Sometimes the company buys regional companies and they consolidate ownership but keep the existing regional brands due to their local customer loyalty.
Sometimes companies have one name and aquire another company and combine names. Like GlaxoSmithKline.
Which where three different brand names. | 2c772e99-8423-43cc-ae55-6de02e0b08b7 |
cingov | what stops lighters from exploding when you use them. | For combustion, you need oxygen. There is no oxygen inside a lighter. When the butane inside a lighter is released, it reacts with oxygen in the air to make fire. Because there's a much higher pressure inside the lighter than outside it, oxygen can't get in while the trigger is flipped "on" since butane gas wants to get out into the lower pressure and oxygen doesn't want to go into the higher pressure zone. Even if oxygen wanted to get into the higher pressure zone, it's being consumed too quickly to get in. | 366a59ab-8dad-4d32-b2b3-2f896ce59f01 |
cinq0g | If a movie finishes post production early in a year but isn’t going to be released until the end of the year, where is the actual movie put until it’s released? | Nowadays, it's mostly kept on computers, ideally in a large, properly equipped server setup with redundant backups and good security.
In the past, film production companies typically had physical storage areas available for film reels, both to keep them prior to mass production and also to serve as an archive. Today, Disney talks about bringing movies "out of the vault" in a purely metaphorical sense when returning them to circulation, but it used to be an actual archival vault they were kept in until needed/wanted. If something happened to that vault (fire, accident, ceiling leak that went unnoticed for a few months because no one ever went back there), it could result in the physical loss of the original/master copies, which in turn could result in a film being completely lost if a digital copy hadn't been made. | 3c1b8f90-5a16-43fd-bd15-fcee760f152c |
cinso9 | How are we able to determine how old a star is and how long it will probably live? | Stars "live" for a characteristic *approximate* lifespan based on their mass, composition, and luminosity (how brightly they burn). We can pretty accurately estimate all three of these, by splitting the incoming light from a star and examining it. Different elements absorb light at different frequencies, so by studying the gaps in the spectrum of light we can tell what the star is (mostly) made of. Because stars all start off as balls of mostly-hydrogen, this also gives you some information as to how old it is.
Luminosity is a matter of figuring out how far away the star is from us, and how bright it appears to be. Mass is a little more tricky, but can be inferred to some extent with a number of methods. Put it all together and you compare this star to the many others we've observed and classify it. Once you've done that, you have a pretty good idea based on its composition and luminosity just how long its lived, and how long it's likely to live. | 58cbcba5-e181-4d12-889b-2750955db426 |
cintr9 | why do large amounts of flammable material in a small space explode (ex: gasoline can) when ignited instead of just lighting on fire and burning like wood | Burning causes things to expand, heat up and release gases. if its in an enclosed space such as a pipe, grenade casing, gas can, etc... then the pressure from these reactions builds up causing the big bada boom. | 20902e6f-a35e-45e8-aee7-4d84f4166e8e |
cinwsq | Why are ice cubes mostly clear but icebergs are white | Light gets scattered when it moves across a boundary, from water to air, or from air to water. If you have "pure" ice, with no tiny air bubbles, it is perfectly clear. The more air mixed into the ice, the more white and opaque the ice is, because light gets more and more scattered every time it crosses the edge of an air bubble.
When you make ice in an ice tray, you fill it with water and freeze it all at once. Very little air, mostly clear ice.
Natural ice formed from layer upon layer of compacted tiny ice particles will contain more air. | fa7d3d94-0a80-4a55-b448-7357fc162521 |
cio3ss | We have ways to create mass ammount of heat using chemicals, what about cold? | Cold is nothing, but the absence of heat and not a distinct entity that can be created and has a mind of its own. So, it should be viewed as a baseline state that changes with addition or removal of thermal energy. Said removal happens automatically in nature with rapid dispersion of heat to the environment via infrared radiation mainly and convection and conduction to an extent (gravity tethers us onto other objects to which we will lose heat to if they are colder than us).
Places like CERN has to remove the heat manually which is done according to refrigeration/air conditioning principles with a liquid medium being used to transfer heat energy from place A to place B. This is achieved by slowing down of the molecules of air when they “collide” with the slower spinning molecules of the coolant medium (as heat is simply the energy that spins particles of matter faster). In return, the coolant’s particles spin faster following these collisions. If you pump these particles to somewhere else, then the net effect is cooling down of the place that they were removed from.
So, there is no “freeze gun” that spews freezing cold magically onto objects, and sci-fi writers would be more scientifically accurate if they replaced it with a “heat removal gun”.
Hope this helps. | 56f62d7b-6e58-488e-87ac-58e28611db86 |
cioeuv | How do fish gills extract oxygen from the water? | The gills are a series of very thin membranes through which blood can flow. The membrane is so thin that gasses can cross through via osmosis. Basically, if oxygen is higher on one side, it will cross the barrier until the concentration is equal on both sides. The same thing will happen with carbon dioxide, ammonia, water - anything that can cross the cell membranes.
It should be noted that all of this happens in the alveoli in lungs. The main difference is that since the alveoli need to say moist and you are not underwater, the alveoli are kept inside big sacks that are more or less climate controlled.
Gill don't work well outside of water because they also need to stay wet and when they dry out they start to stick together. When the membranes stick together, the sides touching each other *aren't* touching water or air, so they can't dissolve anything into or out of them. | a95f4ab4-22a5-4352-89f1-b25dbd237169 |
cioo2l | How the US lost the ability/technology to land on the moon, after 50 years of industry advancement | We haven't. In fact Nasa plans on putting a man on the moon in 2024. Planning missions like these takes a long time in advaced, because literally every contingency needs to be planned for. Not to mention we plan to use it as a test for a new rocket design. These things have to be built, people need to be trained to fly them, Experiments need to be decided for the launch, etc. These things take time. | f5b1e000-739b-49fc-97b5-45fe5390801e |
ciosvx | Why does rubbing something make it feel better? | It’s called the gate control theory of pain. Pain signals enter the spinal cord at a certain level. If you rub the area, you send many non-painful sensations of touch and pressure to the spinal cord that enter at that same level, basically flooding the input and preventing so many pain signals from getting through and up to the brain.
Imagine someone was shouting insults at you (the pain). Then imagine that 50 of your friends were shouting compliments at the same time. It doesn’t hurt so much now. | 9ab8a3f5-35cb-4659-82b5-5d3ccafd1c6c |
cip4rr | Why do baguettes get hard and stale faster than typical cut loaf bread? | French bread has only four ingredients: flour, salt, yeast, and water. No fats. Other breads can contain fats like dairy, oil. It’s the lack of fat that makes French bread get hard and stale faster. | 6f3ff52c-a751-44b4-82b0-1a4154bf50c1 |
cipcjb | How do they test and measure baby eyesight and prescribe corrective lenses since the babies are uncommunicative. | Babies are not talkative, but you can very well observe a babies reaction to various eye sight tests. An example are the Heidi tests which have various smily faces on differently contrasting backgrounds. Even a baby will react to facial expressions and this way you can conclude things about how well the baby can see. It takes more time obviously, but there are plenty true and tested methods. | 5c7e6945-f670-40d0-a0bd-62c7f6621933 |
ciq04r | Why does cold alcohol seem to go down easier than when hot/warm | You generally don't taste things as well when they are cold, so cold alcohol is a bit easier to take that warm. You actually taste it just a bit less. This is the same reason why melted ice cream at the bottom of the bowl is just so darn yummy. One of the theories behind this is:
Your tongue sends signals to your brain. Warm food actually changes the way your tongue sends those signals at the level of the individual cells, so the signal is actually stronger with warmer foods! | 85ee44e8-b51e-44b2-a7d1-52b45988d5d2 |
ciqlq4 | Why do paper cuts hurt so bad? | The way I understand it is that paper isn't completely flat, it has jagged edges so it's almost like a cut from a jagged knife. | 1a21d5da-0032-4bae-be86-f3922b81dfe5 |
cir82s | Does time have physical properties? | Interesting question. Most physical properties are defined by time. Ex: Velocity is distance per an amount of time, acceleration is a change in velocity per an amount of time. As such, you could say that time "turns acceleration into velocity", or time "turns velocity into distance". Thank you for making me think, and lmk if you have any further q's. It sounds to me like you'd enjoy a rundown of relativity, but I don't give those out unless people ask for them. || Edit: If you want to get into really deep physics, time could be described as the only force that actually exists due to relativity. Mass is drawn towards regions of slowest time. This means that gravity is merely objects moving towards places where time is slower for them, as well as electromagnetics and the strong and weak nuclear force. Ultimately this is just a thought experiment and has no real applications in physics tho. | af3550ed-6908-4b2e-93ba-1e8d9afc393b |
circy1 | Why do our eyes turn red in pictures? | Light reflecting off the back of the eye (the retina)
Fun fact: doctors actually test for this in kids. It's called the 'red light reflex,' and not having it is a sign of a tumor that can happen in kids or cataracts. | f811e94b-f343-425f-85b8-e2c0e2e7942d |
cirhtc | What do the US Marines do? | The Marines as the British Empire used the term were originally the soldiers on a ship. They were the ones that boarded an enemy vessel, or went ashore to claim a beachhead. In the US they had the same role. Over time they grew large enough that they were separated from the Navy but they still have close ties with it operating as security on Naval vessels and the like.
In modernity they are the "Tip of the spear". This means that they are essentially shock troops. They are trained to be among the first wave of an attack and take control of a piece of territory. In particular they "specialize" in water to land attacks. From the Spanish-American war onward, and in particular WWI every Marine was a trained sharp shooter so they were among the first to develop the modern concept of sniper in the US military. | e3c052cd-4f65-4d18-b21a-9f36f1efdd69 |
cirn9h | Why kids(6ish) can sleep so heavily, easily, and through things, and why adults can't? | Are adults supposed to be light sleepers? I have to set like 15 alarms to wake up and have slept through a gas explosion right down the street lol | d5671d8a-ed1a-4e63-b0d4-de46864652ae |
cirpdn | How does a solid state drive work, physically and in terms of memory, compared to a hard disk drive, and what happens to both when you delete/overwrite files? | Hard disks are composed of spinning disks that can be magnetized or de-magnetized in order to store data. To read or write on a certain part of the disk, the target region of the disk must sit below the read-write head. This part of the disk is then either re-magnetized or measured by a magnetometer. To achieve this, the disk spins, and the head moves closer/farther from the center of the disk. This means that memory access speed is limited by how quickly the disk spins and how quickly the head moves. Solid state systems, meanwhile, store data in special transistors. These transistors are arranged in such a way that a few electrons get trapped inside or outside of a part of them, and these electrons can be detected by the special transistor. These electrons are moved by other transistors in a network that decides which particular bit of the drive is to be read. The speed of these drives, if fully optimized, is primarily limited by how quickly data can be squeezed through the wire and terminals that connect them to the processor/RAM. In reality, (I think) these drives are limited by how quickly they can detect and communicate the presence of this excess/lack of electrons. | 973bda59-5512-4829-a044-0b1fcd5f144a |
cirwh9 | Why are auroras mostly seen in high northern and southern latitudes? | The Earth is a big 'ol magnet. In space, there is a constant onslaught of charged particles (often electrons and protons) coming from the sun, other stars, and pretty much everything in space. These particles are deflected by the Earth's magnetic field, and due to some weird physics stuff, often find themselves bouncing between the north and south poles at high speeds. This means that they travel in these huge arcs over most of the Earth, and are lowest at the poles. Sometimes, these particles are low enough to hit the atmosphere. When they do this, they generate light due to the immense energy that is released in the impact. This light is the aurora. | 5141fac5-137a-4ea1-87d1-c700232b8ce6 |
cirwu4 | why do cherry flavored things taste bitter while actual cherries are sweet and sour? | I absolutely hate fake cherry flavor... I didn't eat cherries for 21 years of my life because I thought they all tasted like cherry candy... | f82526fe-f742-44d3-8b28-821155070d61 |
cirysw | How do salary caps and computing for future salary and cap space work in team sports like basketball? | Team A has a $50m budget because they have a rich donor.
Team B has a $10m budget.
Team A can afford to lure multiple top tier players and therefore always walk all over Team B. Salary caps help to stop teams buying their way to the top of the ladder and even up the playing field. | c24aa22f-13db-4930-8de7-e4579f21105d |
cirzw3 | Why does gelatin melt when stored in the freezer or chiller? | Gelatin works by creating a medium-loose bond between water molecules using collagen which is a type of protein. When you freeze prepared gelatin, the water molecules break the bonds with the collagen. These do not reform properly when it is thawed. I have not tried completely melting the gelatin again to see if it would re-set, but it seems unlikely.
As far as why it is dissolving when submerged, gelatin does that when left submerged even at room temperature as far as I have experienced. I think the water dissolves the collagen bonds as it tries to form a homogeneous mixture. | 08cf087a-2973-4fc9-a0e8-e74b81d6cb4a |
cis3fc | What are Turing shaders? | [Turing](_URL_0_) is a microarchitecture (a type of chip) from Nvidia. It's used to build GPUs (chips specialised for graphics) with support for more general purpose parallel programming (GPGPU) as well. Turing shaders are programs written for this type of chip. | c17b7eea-66ba-44c7-a112-b296a4e40932 |
cis3qm | Why do drones usually have 4 rotors - has this been proven to be the best (most efficient or stable) design, or is it possible that a different number would be better? | An even number of rotors makes it easy to prevent unwanted spinning. Each rotor spinning clockwise has a twin rotor spinning counterclockwise, which allows the drone body to sit still without rotating. Now, in order to tilt forward, backward, left, and right, the drone needs three or more blades. Four is the smallest even number greater than three, so it is usually chosen. There are, however, drones with more rotors. I've seen six and eight rotor drones, and there are probably even bigger ones. Usually, for small and simple systems, four works best. Edit, since you lot keep asking it: HELICOPTERS USE COMPLEX ANGLE-SWITCHING ROTOR BLADES AND VERTICAL TAIL ROTORS THAT AVOID THE ISSUE | 9a65766f-5564-4ec2-a39c-7b80a7007ae2 |
cisma2 | What's Foreign Direct Investment? | If a company or individual sets up a company or purchases assets or a significant share of an existing company in a foreign country, that is considered FDI. The assets purchased are located and in use in that foreign country.
Day to day or small trades in shares of a foreign company does not constitute FDI. These typically only reflect in changing in equity ownership (no controlling interest) and does not inject new capital into the firm.
Buying assets and exporting them to another country for use or sale (say capital equipment or products like phones, cars etc) does not constitute FDI. It is considered international trade.
Foreign currency trading or speculation is not considered FDI.
FDI is an important statistic because it implies a long term commitment to operate in the country. These investments are less subject to capital flight risk unlike, for example, trading in company shares/stocks or foreign currency purchases. If a country attracts a lot of FDI, it is a signal that foreign investors have confidence in the economy and, to a certain extent, the governance of that country. Many factors go into building foreign investor confidence - rule of law, manageable corruption, a good track record of fiscal and monetary policy management, stable government, ease of capital inflow/outflow, fewer rules discriminating against foreign ownership etc etc. In more recent times, issues like human rights, environmental policy, labor laws also play an increasing role in the attractiveness of a country for FDI. | b6d28407-b0ac-4581-adff-88edfe29620b |
cisnon | how do motorcycles go from being upright to almost completely leaned over to back up again? | Once the motorcycle is moving, the rider pushes on the handlebars to lean the bike and to stand it back up.
Push on the right bar to go right, push on the left bar to go left. That leans the motorcycle over. The harder and longer the push, the more it leans. The more it leans, the tighter the turn. Relax on the bar and the motorcycle continues to turn in the direction it's leaning. To stop the turn, push on the opposite bar and the bike stands back up. How much you have to push varies from motorcycle to motorcycle. A well set up motorcycle needs no control inputs on the bars to go in a straight line and once leaned into a turn will continue to turn at that radius until it's stood back up again. | 17849980-e901-453e-916c-0445a43bee9b |
cisoic | how do motorcycles, when cornering, go from being upright to almost completely leaned over to back up again? | The path the tires follow works with inertia to adjust the bike's angle. Starting a turn, you actually have to steer *opposite* the direction of the turn to get the lean going. From there it's a combination of steering and slight shifts in body weight to maintain course. When you want to straighten out again, you steer a little more sharply to, in a sense, "put the bike back under yourself."
Really it works the same way as on a bicycle, but with a lot stronger forces involved. | 9efeae2c-021c-47d1-8609-a915513978e5 |
cisp4h | What's a benchmark interest rate and a prime rate? | A benchmark interest rate is set by independent financial institutions to show how expensive (i.e. at what rate) banks or funds can get money from the market (bank to bank transactions of borrowing money). The independent financial institution collects estimates from a panel of various banks on what they ecpect the rate to be at which they can borrow money. This is then used to calculate the benchmark rate.
One way a bank makes money is borrowing money to companies at the benchmark rate +x% where their profit is basically the x%.
A prime rate is the interest rate a commercial bank (a bank you and I use) will offer to its best customer for borrowing money. The prime rate partly depends on the benchmark rate and is also calculated as benchmark rate +x%.
Sorry if its not ELI5 enough, i tried my best. | 51daa01e-06a4-475b-94fc-9f02df3c3474 |
cit20n | How do we know that the sun was formed around 5 billion years ago? | There are various methods, such as using computer models of stellar life cycles, but the most tangible way is simply that we know that other things that probably formed around the same time as the Sun were formed around 5 billion years ago.
It's likely that the entire solar system (the Sun and the planets) formed at roughly the same time, so to approximate the age of the Sun, we can take a look at the age of objects in our solar system. The oldest meteorites we've found are approximately 4.6 billion years old, according to radiometric dating; round that up to 5 billion and there you have it. | 87a6299b-6420-4c95-a7b0-1e8a19c90c40 |
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