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c0l4ht | this math quote from the King Killer Chonicles by Patrick Rothfuss | The math Rothfuss used is wrong. Infinity divided by infinity is undefined. What this means is that the function ends up having no meaning. Its the same as dividing by 0. If you divide an orange, i.e. cut it up, you can't cut into 0 peices. That would mean you never did anything tobthe orange in the first place. Infinity is not a real or rational number, its an more of an idea of a really big number.
The second part is also wrong, A finite number divided by infinity will approach 0. Think of it like 1/100,000,000. Thats a really small number. 1/infinity is even smaller, so small we effectively call that 0. This is used in calculus a lot to solve math problems. In Rothfuss's example even if the numerator is a big number itself, infinity is by definition bigger, so the math reduces to 1/infinity, which goes to 0. | b2a73147-51d7-411f-a799-20b8da033e63 |
c0l9r8 | How do dark green bottles prevent the beverages from degrading? | You know how if you leave something in direct sunlight for a long time it gets "bleached" by the sun? That's because some of the light the sun gives off is energetic enough that it can damage pigment molecules in the object and changing the color it appears to be.
The same thing can happen with other things, like compounds in the things you mention. As the flavor of, say, wine and beer are often subtle and we want them to stay consistent (not removing the molecules of stuff that are responsible for the flavors we want and not introducing *new* stuff with their own flavors as byproducts of the other stuff breaking down), we try to protect them from the harmful light by putting them in containers that will hopefully prevent that light from getting to the stuff inside. | 4f72a6fb-a01d-457b-85a9-195ea6543a2b |
c0libr | We cast things out of steel or other material, but before that we didnt have those 'machines for creating another machines' and had to use more primitive tools. How our ancestors managed to craft something that it looks impossible to make without machines we have today? | You did it by hand and simple machines often powered by human/animal or running water.
Blacksmiths shaped metal with hammers and fires. That is how metalworking was done back in the day.
Simpler machines made from wood was often used. Metal have historically been quite rare and wood, stones, clay etc is was was used in the past
Casting metal with lower melting temperature is not hard. [Lost-wax\_casting](_URL_0_) when you shape the object in wax, pack in in sand and clay and then you heat it up and the wax melt and can be reused. You then pour int molten metal like bronze that you can make on a fire in a burned clay container. So you need wood, clay, wax and the metal to do that.
The metod have been used for 6 000 years and you have complex statues like [Dancing\_Girl\_(sculpture)](_URL_2_) from 2500BC
So it is stuff that is easy to find and wax can be bee wax. The most uncommon was the bronze but there was mining of metal deposits thousands of year ago. They mined metal that was closer to the surface with high metal concentration. Deposits like are rare and almost all have been completely mined out so metals is harder to get today.
Look for example a [Primitive Technology](_URL_1_) where stuff is made by hand with stuff he find in his surrounding . He manage for example to create small amount of iron with stuff from his surrounding. | ade17436-f055-4832-a32a-34379510d7c1 |
c0ll7j | Does everyone in a city pay for the public schools in a city and why aren’t kids allowed to choose the public schools they want to go to? | All the tax money that pays for public schools comes from the district and state, and sometimes even federally. That really depends on the specific school.
Schools are allocated money according to their population. More students need more baseline money. Additional money is rewarded to schools that do well.
That last bit is what sucks. Poor schools do poorly, then don't get enough funding to do better. It's a vicious cycle that you seem to be caught in yourself.
And you *can* choose what school you go to, provided you convince them to let you transfer. The requirements to do that vary greatly beyond districts. Ask a counselor.
EDIT: As for the separate but equal question, the US doesn't exactly enforce ethnic neighborhoods, so, they're not really 'separating' them from better schools. | 11076859-54d0-4fde-9f1a-38cfaa05597f |
c0lmxt | How does a SSD read data quicker then a HDD. | An [SSD](_URL_0_) has memory chips inside, so "reading data" is just a matter of the electronics inside the SSD to find where in memory that data is.
A [HDD](_URL_1_) stores data magnetically on platters (disks). Sort of like magnetic CD's. Reading data involves moving an arm with the magnetic heads to the position on the disks where the data is, and then reading it.
So even though the robotics inside a HDD are pretty fast, physical movement is still much slower than electronics speed. | cd7f5206-d6c4-49cb-8322-b437003f15a5 |
c0m162 | How do flies get into surfaces where they don't fit into | I suspect that the body of the fly is smaller then you suspect and it can get deformed.Holes in net to keep insect out is smaller then that for a reason.
Look at [_URL_0_](_URL_0_) for a human trough a hole.
The limitation for a human is the width of the chest and the width of the head (you can turn it 90 degree). So humans can fit trough smaller holes the you would expect. | 3aa0bf78-905f-49f6-aefa-ba122180127c |
c0ma11 | What causes our brain to react to something in a motivated or dejected fashion? | literally dopamine.
two mains ones I'll discuss (jus know there are many at play) are: Dopamine and Cortisol.
when we do something we enjoy like laughing while watching television, our brains release this neurotransmitter called Dopamine. Dopamine makes us feel all good inside.
when something happens that we don't like, our brains release cortisol. like when we experience physical pain or whatnot. Cortisol is responsible for being like "wow, I kind of hate that, Imma avoid doing any of that stuff again".
obviously over-simplified. but, you kind of get the drift, hopefully. | 36d3122f-6628-463b-bc28-5a055c171df4 |
c0mb89 | How do carrion not get sick from eating rotten meat? | Their stomachs produce digestive fluids that are more acidic than animals that avoid eating rotten meat or eat plants. The high acidity kills the bacteria. | dc72ffcb-772d-411a-84a9-2dd6126c8d76 |
c0meio | Why is depth perception messed up in low light? | The sensors in the eye are not spread out uniformly, the eye is not a camera. The ones that feed into depth perception best, the cones, are denser in the center of the field of view. The ones that see in low light best, the rods, are denser around the edge. | bbc5eb2d-47f0-4469-a951-bd516798877d |
c0mncp | how slavery worked in prehistoric/ ancient times. | They couldn't. Rome had three slave uprisings during the Republic that turned into full scale wars. The uprisings that were less successful dont get mentioned.
Spartacus and his army could have escaped Italy at one point even as they had made it to the Alps. But for some reason they turned around to keep fighting the Romans.
After these three though you hear less about slave revolts. Maybe it had to do with Spartacus and his army getting crucified along the Appian Way. Maybe it was the new laws that forced people to be more humane to their slaves. Most likely it was the fact that you could easily become freed as a slave within your lifetime so your chances were better through that route.
And at least you got to order your master around on Saturnalia | 11eddb74-5cb3-4008-9f44-2e0e89adf1ac |
c0msjj | What determines where you get in intramuscular injection? | If it’s a small amount of medication that needs to be injected, it will usually go in your arm because that’s the easiest (and least embarrassing) to access. But the deltoid can only hold so much so if it’s a larger amount of medication, it needs to go in a bigger muscle. For the butt, it’s actually a particular spot on the butt, not just some random but spot. They have to target a particular muscle but also miss the major nerve that runs through there. But if they can find it properly, it’s a good spot to accept a large amount of medication without interfering too much of the spot is tender afterwards. Another spot that gets used is the front of the thigh, which can also accept a large amount of medication but can be more bothersome if there is irritation afterwards at the injection site. But if someone is acting all crazy and/or aren’t able to cooperate with the relative precision needed for a good bit shot, then it’s much easier (less precision necessary) to do it in the thigh.
It’s all about finding a muscle that can take the volume, has a low risk of hitting a nerve, is as unembarrasing as you can manage, and minimizes the chances of injection site issues afterwards. | a4e00ea2-b3dc-48b9-8b68-1607e01e7b25 |
c0mxb6 | If plastic is non-biodegradable, is it possible to integrate it into building materials to “lock” it out of the natural environment? Why haven’t we done so already? | It's possible, but plastic isn't very strong compared to other building materials (concrete, steel, even wood), so it makes for fairly poor building material. We choose for efficiency over building material instead of trying to recycle plastic into inefficient building materials. EDIT: Since plastic is a petroleum product, I'd imagine it's not very fire-resistant either! So safety is probably an additional concern.
Also, putting it in building materials wouldn't "lock it out" of the environment as much as it delays it getting into the environment. When buildings are torn down all that demolition waste has to go somewhere. | 1d2cb659-506f-42ff-a9b2-9b13a97ae075 |
c0mzww | How can we retain memories when the body "regenerates" ever 7 years? | The idea that no cell in you is older than seven years is incorrect. Your surviving neurons, where your memories are stored, are as old as you are. | 4dae23be-3927-4a2a-b7e0-5695e14c0fb9 |
c0n4ko | What's the difference between guitar amps and speakers? | A guitar amp & speaker is designed to change the raw sound of the electric guitar. This is partly to do with history, and partly to do with physics.
The physics of the electric guitar means that is you put it through a high fidelity amplifier - like a PA, domestic hifi or even bluetooth speaker - it sounds rubbish. Guitar amps have evolved over time from trying to be high fidelity to sculpting the sound to make the guitar sound as good as possible.
The downside of that is that sculpting is that if you try to use it to replace a high fidelity amp, then it sounds like you have found; rubbish.
These days an alternative approach to guitar amps is to use amp and speaker modelling to give you that good sound, which you can put through a hifi amplifier. Aficionados may say it doesn’t sound as good, but it’s more convenient and less expensive. | 90e1d438-74d8-45fb-97a8-6a5c2074416d |
c0nbz6 | Why are there not Audiobook and Ebook streaming services like Netflix, where a member can access as much content as they want, without paying a per usage fee. | Dunno but I would sure appreciate streaming audio at a better price. I am low vision so this matters to me.
FYI the Librivox website and apps give free access to volunteer recorded audiobook readings of selected Project Guttenberg Public domain works. I also get professional audiobooks via the Libby app from my public library although usually there is a wait of several weeks for popular books.
My bigger beef is the Audibles style of audiobook "performance" where both male and female narrators read dialogs in falsetto for women and gruff dude-bro voices for men and recreate conversations between groups of characters that sound like old WW2 movies with "Tex" and "Brooklyn" talking to "Boston", "Okey" and the "Limey".
I prefer the "unvoiced" readings of Blackstone Audio and Books on Tape. I'm not alone in only being able to listen to Audible audiobooks at x2 or x3 speed to supress the horrible "performance" aspect. Lately I find listening to computer generated text-to-speech preferable to listening to Audible.
I never have trouble keeping track of who is speaking in dialog when listening to the computer monotone but damn I hate narrators who "characterize" the dialog and emote the narration. Usually they have no time to prep it seems and they emote keyed to the individual words not the context. E.g. a character sounds happy when they speak the word "happy" in a sentence like "She was happy to learn now that ultimately they were planing to destroy her life." | 521bf671-58fb-4e4e-a022-246ff8dcc97c |
c0nr8e | What is the Holographic Principal? | I don't have much knowledge on the topic, but I will only correct the question. It's **Holographic Principle, not Principal.** | ca23ea27-4a74-4c4e-b63c-5d198864cd7d |
c0o20x | How do marketplaces (e.g. _URL_0_) handle currencies? | > And would that not be a problem when the hotel gets paid?
No. _URL_0_'s bank and the hotel's bank would work it out so that the hotel gets paid in their preferred currency.
& #x200B;
> I book a hotel in the us in GBP and then choose to pay on arrival, do I pay in the exchange rate when I booked or the exchange rate at the time I made the payment?
On arrival. When you make that reservation, _URL_0_ would promise the American hotel a certain amount of USD. You would be responsible for paying them that much USD, regardless of exchange rate fluctuation. | 7fb4f714-3454-4b58-bcac-b976a1920162 |
c0o78n | what the proposed extradition bill means for Hong Kong and mainland Chinese citizens (please and thank you) | China and Hong Kong is under a one country, two systems type of structure where Hong Kong could do it's own thing and China wouldnt interfere, which also included criminal prosecutions. Under this proposed bill criminals in Hong Kong can be extradited to China and prosecuted under Chinas laws, which effectively shatters the one country, two systems format. It means nothing for Chinese residents but have huge implications for Hong Kong residents as HKers are now potentially subject to the more restrictive Chinese laws and criminal proceedings. | 4c321337-67d7-4686-b1d6-3bf4c58ed7af |
c0okbk | How does a battery continue to support the exact same functionality as the charge decreases over time? As in with a phone battery, how does the screen not get slowly dimmer, sounds from the speakers quieter? | First of all, I'll make a slight correction to your question:
"maintain the same amount of voltage as the amperage decreases"
Actually, it's quite the opposite. It's the **voltage** that decreases as the battery is discharged. The current (amperage) mainly depends on what is connected to the battery (what we "demand").
And the voltage can have some dramatic drops when the battery is discharged, from 4V to 3V (25% less), or even from 4.2V to 2.7V! (35% less) Normally, this would be quite noticeable, as you correctly imagined when you asked the question.
& #x200B;
So, in order to avoid this effects, there is an extra circuit in the devices. This circuit maintains a fixed output voltage, independent of the input voltage. This is called a buck-boost, or step down-step up.
This circuit works by converting the input voltage (whatever it is) into the output voltage just like a Transformer does. The only rule you have is that Power in = Power out (+losses).
& #x200B;
As an extra:
Electrical power is calculated as P = I\*V, where I = current and V = voltage.P(in) = P(out), so V(in) \* I(in) = V(out) \* I(out)This would mean that as V(in) decreases, I(in) must increase in order to keep the total power (brightness of your screen) fixed. This would mean that the current (amperage) actually **increases** as the battery discharges. | 49d61482-8efc-432f-8c7c-693d58404d79 |
c0opny | How do these computers work at a library where you put stacks of items on a shelf and it automatically checks them in or out without scanning barcodes? | RFID.
The books have a thick sticker, probably in the back cover, with an antenna programmed to that book.
The shelf reads those tags.
Source: worked in library that made the transition to those tags. Tagged several thousand books. | 994ec186-1a96-4b2d-801c-8dbdc5bb98ae |
c0ox60 | Why do some bands re-record songs for music videos when they already have a album version? | Very often they’re actually remixes or edits. One major factor is time. On the album versions they tend to be longer, because nobody minds. There are different edits and mixes, for radio and ones for video.
While less of a factor today due to much better electronics, another problem was speakers. When watching a music video, you were listening through a crappy small 2 or 3 inch speaker on the television and radios were usually tiny speakers too.
To this day, you’ll find lots of different sized reference monitors in a mixing studio. I worked with a producer who insisted I run the recordings we did through a hand held radio with a 2” speaker, for these reasons.
As for time issues, say the album version is 5 minutes but the video is 3.5 minutes. They might change where the guitar solo is, or use a vocal section that is more well suited to a shorter time.
Rarely though is it a completely different version. Usually it’s just remixed and edited to the point is basically has become distinguishable. | 9da0d860-714d-4495-baa6-59dd17d15fb7 |
c0oxm9 | How can fizzy drinks go flat if shaken before opening despite having probably been shipped in from overseas and/or jostled around in the back of a truck for days?? | Shaking doesn't make go flat unless you open them in the shaken state. It you let them sit, all the bubbles of pressurized gas consolidate into the top of the can, and the pressure forces a larger amount of CO2 into solution with the liquid (making it "not flat"). | c8c8b4ed-81b4-4d90-99d9-cea9f54a0306 |
c0oz3y | How do those top down, 360° car cameras work? | My wife's car has a camera in the front bumper, camera under each mirror, and a rear camera. It basically takes the image from all 4 cameras and puts them together to simulate top down view. I assume it's similar with all cars with this feature | d74b0f3d-3545-4100-8426-5c8bb1a12662 |
c0pc4m | if vehicles have the ability to go from 2WD to 4WD/AWD, why aren’t there cars that let you change from RWD to FWD? | There are, so there's that. It's just not practical in pretty much any application so it's very rarely done. There's almost never a need for it except in very specific off road conditions. | 5759615f-5427-42d2-8e22-f50572818ce5 |
c0pr37 | Why do full frame DSLRs deliver optimal performance at ISO 100 while many digital cinema cameras with smaller recording areas perform best at 800? | It's easier if you think about this the opposite way around — let's imagine we're designing a video camera.
You rarely want to use a super-wide aperture for video, because you need the depth of field from a tighter aperture, so you lose out on a tonne of light from there. The usual rule of thumb is that shutter speed = 2x frame rate, so you're going to be shooting in the 1/60"-1/50" range, or thereabouts. Not crazy fast, but not super slow either. Given those limitations on shutter speed and aperture, you're never really going to be filming at ISO 100. Something at or above 800 is much more likely.
So now we're going to design the sensor. There's nothing special about ISO 100 that makes it particularly appropriate to target that as your base ISO, and you know you don't need to handle low ISOs but need good performance at higher ISOs. So you design the sensor from scratch around a much higher base ISO.
The important point here is that the video camera won't produce an image at ISO 800 that's anywhere near as good as the photo camera will at ISO 100 (given appropriate shutter speeds and all that), and won't outperform a larger sensor built on similar tech either. Rather, the video camera designed around base ISO 800 will produce a much better picture at ISO 800 than a photo camera (with a similar-sized sensor, but designed for ISO 100) will produce at that same ISO 800. | 0fad71a4-c3d2-4597-bc31-df240cde23fb |
c0pu6l | What happens to the POTUS and other high value passengers in the event that Air Force One can no longer maintain flight? | They land successfully or they all die. [There's no escape pod or parachutes like in the movies.](_URL_0_) | 83076bdf-ace6-4d50-972a-79e17a3e51cb |
c0q9w4 | if the economy is so strong, why are so many businesses closing? | need more than just an anecdotal response. which specific businesses are you referring to? what field are they in? for non mom and pop stores, there's a delayed effect. stores can take a few years to see the effects of change before they close down. | d58dfe7a-08af-4b90-afc6-932b729e072c |
c0qati | What lead to the situation know as Highway of Death, Kuwait in 1991? What happened afterwards? | When the collision invaded Iraq and Kuwait the main thrust was in the desert west of Kuwait. The then started to turn east toward the Persian gulf/Tigris river. If they manage that the Iraq forces in Kuwait would have been surrounded and cut off.
So they attempted to escape and was spotted on the highway and attacked by coalition aircraft and a lot of vehicles was destroyed and a lot of solders was killed. But is is estimated that many time more solders manage to escape the was killed.
A lot of vehicles out in the open close together along a road where many of them would have problem moving in the sand around it resulted in a traffic jam when aircraft attack the front and rear with cluster bomb. Then there was more airstrikes for the next 10 hour.
Concentrated troops and vehicles in the open when the enemy have total air superiority and you have no air defense result total devastation of the attacked targets.
& #x200B;
You can the moment of the collision forces on [_URL_0_](_URL_1_) and the Highway of Death is the road from Kuwait City to Safwan across the border. I am not sure exactly where along the road the the well know images are from but the coordinates on Wikipedia is just north of Al Jahrah that is also on the map
I am not sure what you mean by what happen afterwards. The war ended the 100 hours after the ground assault started and then the road was cleared. | 6596363f-e3d7-4c72-b79f-e191bcfad2ec |
c0qc6a | How does the Hubble telescope, moving 8 km/s around the Earth, take clear and well exposed pictures of interstellar formations light years away? | When you're driving down the highway, the bushes right on the side of the highway appear to be zooming by at incredible speed, while the mountains in the distance dont seem to be moving at all. This is an effect called parallax.
Now imagine how incredibly little the interstellar formations would seem to be moving when they are many orders of magnitude further away. All the telescope needs to do it slightly adjust its angle to stay pointed at the right spot. | b4693a39-7cda-4417-a130-4a6dde8c2e6f |
c0qftc | How does the gravel under train tracks stay level so the train doesn't make it slide? | More than anything, the tracks themselves are made using strict guidelines. This helps to keep the weight distributed well across all the wood at the bottom and in turn the gravel/dirt underneath it. The gravel also does a very good job of holding the dirt underneath in its place keeping it from moving around. | 511e341b-209f-49bb-8f7c-b23fd69b7466 |
c0qn8g | How do we know what dinosaurs sounded like? | We don't actually know what dinosaurs looked or sounded like. Basically every image or video of dinosaurs we have, besides skeletons, are an artist's best guess. | 36d1e0f8-1103-425d-8c24-6f5ab3272742 |
c0qntc | What makes parts of our body, such as the hand, feel temporarily paralyzed after hitting it against something? | Signal overload to the brain; it temporarily can’t send signals back to the muscles.
Essentially the same as loss of circulation causing a body part to “fall asleep” | aa06b642-5296-4ff1-ba21-c402a09c5c94 |
c0qsrd | How is a knot in your back formed, and why does massaging get rid of it? | The typical cause for a “knot” is a build up of lactic acid (muscle exhaust fumes) in the muscle. If the lactic acid does not leave the muscle through some sort of stretching, manipulation, hydration, etc. the muscles start to pretty much stick together. This causes the muscles to be sore and form what feels like a knot. Massaging the “knot” releases the crud from the muscle and allows it to go back to normal. The more formal name for it, by massage therapists at least, is an adhesion.
Bonus: the main reason it is so prevalent in the back muscles is due to the amount of activities in daily life that force us to work directly in front of us, which bring the shoulders forward and over stretch the back muscles (using computers, cell phones, and pretty much everything we do) which makes it more difficult for the muscle to flush the toxins.
Source: Massage therapist | 503efd93-28cd-4cea-a623-e3d1f7fd2489 |
c0r4hd | Boltzmann Brain | It is a thought experiment. There is a non-zero chance that you could just be a disembodied brain floating around in the universe and everything you think you've experienced never happened. It's not particularly likely - you probably actually exist. | 91d5025c-5708-4bdc-93dd-428eac32fdd8 |
c0rgny | Can someone explain to me how RAM works? | RAM stands for Random Access Memory. That doesn’t mean random like, give me a random piece of my memory, but rather you can quickly access any part of it.
RAM is where your computer stores all its active data. A hard drive stores all your permanent (well, long term) data. Say you have a movie file, its gonna sit on a hard drive until you go to use it, and then, you will typically need that data from front to back. So speed is less an issue, but a movie can be a big file these days, with 4k and what not.
Ram is where all your current active information is. When you open a web page in google, the information that says “this is the text, images, etc. and this is how they are laid out” sits in your ram, and as you scroll and interact, they data is constantly changing, so your computer needs access to that data, and fast.
More RAM will only help your computer if your are using a majority of it. As your ram fills up, your computer has to figure out what stays and what goes. It can put some of that data over to a hard drive or slower storage, or just throw it away to make room. If you are pushing your RAM limits, the computer can also compress (like little zip files) of data onto the ram, but then the cpu has to decrypt that when it needs to edit or use that data again, so additional ram helps in that regards too. | 7d1dbd6c-b5cf-420e-af3e-a8ab42ca5ced |
c0rms0 | Why does spit/saliva work well as lube whereas water does not? | Spit contains tons of little protein chains! It's just like egg white, ejaculate, or mucus (well, it is mucus, watered down). It's why the egg white or the snot can stretch so far before the strands snap.
So, those chains have a sort of tensile strength, but they're slippery against one another, and that allows them to lubricate. | 82658101-6025-406f-b8c8-8230866e6102 |
c0rnbr | Why is the sky pink in the east during sunset occasionally? | That's called [the "venus belt"](_URL_0_) and what you're seeing is the redder light from the sunset lighting up the atmosphere. | d82051e6-7846-417a-8342-cb8b8eb4a849 |
c0rni7 | Why does meat that has been frozen for a short while taste fine cooked but not when it's been frozen for a long time? | Freezer burn, in short. It's caused by at least a couple of things. First is sublimation. Sublimation is how water changes directly from ice into water vapor without melting first. It dries out the meat. Second, the meat deteriorates due to enzymes from the lysosomes in the muscle cells. This happens rapidly at room temperature. Freezing the meat slows it down a good bit, but over time it affects the quality of the meat.
The sublimation can be minimized by giving the meat juices nowhere to sublime to by vacuum sealing it or similar methods. | 3d44ef6a-c457-4eca-9a6c-f26d76fe89ed |
c0rp6m | Why are we able to feel when somebody is watching us sometimes? | You aren’t able to. It is just a confirmation bias from the couple of times you were right about it. | 5705e871-0b02-4bcd-8379-cfecfb414246 |
c0s00r | Why do egg's come oval shaped, and not fully round? | A oval egg will roll in a circle so it will not move far but a round egg can roll away. So there is a higher chase that a round egg roll away and hit something and get damages or just lost. So animals with rounder eggs will have more offspring sop the result of the evolution is that eggs are oval.
Multiple oval eggs can also be packet closed together and keep warmer.
Eggs of birds that have nest on cliffs have more oval eggs then birds that nest on the grund.
A oval egg is also easier for a bird to squeeze out when are laying them. | 536b7938-d3be-479c-b116-d8d753d89aca |
c0slhm | Are there any other mammals that give birth to identical twins? | You're correct in that animals that give birth to litters (multiple offspring at once) are fraternal and not identical twins. It's possible for *any* mammal to give birth to identical twins, but it's very common, and it's hard to measure its occurrence in the wild because the only way to confirm it is through genetic testing. An Irish Wolfhound was confirmed to have given birth to identical twins (2 out of a litter of 7), but as far as I know, that's the only confirmed instance among household pets.
Once curios exception to this is the Nine-banded armadillo. The nine-banded armadillo *always* gives birth to a set of identical quadruplets. Once the egg is fertilized, it splits into 4 separate embryos that share a single placenta. | 6711300e-5e44-4354-bf41-ec871ee0390a |
c0sorf | Why is sunburned skin hot to the touch? | The warmth of a sunburn generally stems from increased blood flow to the exposed site. I am unaware of any temperature measurements of sunburned skin, but I suspect that even though the burned skin seems much warmer, it would still be close to 98.6 degrees. Any slight elevation in temperature would be a result of the inflammatory response generated from the chemical processes induced by ultraviolet radiation.
& #x200B;
[_URL_0_](_URL_0_) | 38e0e700-4994-4f53-8388-1b4e2a76287c |
c0t22a | How do devices like weight scales and body fat measuring machines figure out the percentage of things like muscle, fat and water in your body? | The scale detects water by putting a voltage across your feet. Because stuff dissolved in water conducts electricity, the more water you have, the more current makes it through.
Fat requires the scale to know your height. The scale just compares your actual weight to the weight of a person as tall as you, but with pure muscle. | 4d43a485-e4fe-4fed-8cba-b3a49154c8f0 |
c0te5l | How can nuclear fusion produce more energy than nuclear fission? | It depends which side of iron you're on
Elements heavier than iron give off energy when they split, the heavier atoms like plutonium tend to give off more energy per splitting than lighter ones like Radon. Elements lighter than iron give off energy when they fuse but need energy to split them apart. Heavier forms of hydrogen give off the most energy.
Iron is super stable and every step towards it lets the atom get rid of some binding energy. | cb7face0-cad8-4b47-b058-d744321d6e64 |
c0tle2 | How do record labels screw certain artists/bands (“360 deals”) and push others to success? | Record labels are there to make money - they help bands by providing capital to afford costs like recording, promotion and touring (that most bands cannot afford outright) and knowledge to do this well (the hired tour managers and marketing people that are experts in areas the band will not be), and then take a cut of the bands earnings in return.
A band does well and the record company make more money than they pay the band, a band flops and the record company loses that investment.
How record labels can help or screw over bands friends on how well they do their jobs - if a band relies on the label to provide marketing for their new album, or to organise a tour and screw this up, then the band lose money...
A lot will come back to contracts - before working together bands and labels will agree terms for the deal. Things like the expectations for the band (write X amount of records, your for X many months), and what the label will provide, and also limitations to try and ensure a fair deal for both parties (the band cannot release music for another label while under contract, or just meet minimum stipulations).
The problem is that contracts can be misused - is a band signs a deal for three albums but loses popularity when the second flops, the record company may not want to invest much money in a third record, but at the same time the band are under contract with that label so they cannot just leave and work with someone else.
You can also see problems like where a new band has released music under a small label, moved on and gained popularity, and now this early music is unavailable as the first record label own the publishing rights and may limit how it is sold | 07222c81-d898-4a81-ad1e-e41d7ff79878 |
c0tqhr | Why do CO2 levels keep rising? | Because we keep burning oil and coal.
Oil, coal, and other fossil fuels are converted plant matter, which we burn to power our cars, our homes, our barbeques, and convert into plastics that we use for everything in life. The burning of fossil fuels and refining into plastics creates carbon dioxide, among other compounds.
Even "green" devices, like electric cars, still are made with materials that utilize fossil fuels for manufacturing and transport, and still plug into electrical grids that are powered partly by fossil fuels.
Until we can get alternative energy to a higher efficiency and adoption, the rates are going to continue to rise with the increased population of the Earth. | fcc2fab9-f600-4d4b-848e-269ee1f98f93 |
c0u3z7 | Why can you still feel it after you manage to swallow something that was stuck in your throat? | You’re not too far off! While I was a lifeguard I learned that. When something is caught in your throat it is pushing against the sides. As you attempt to force air in or out of your lungs to remove the object it causes a slight build in pressure further expanding your throat. (this is why whenever somone performs the hiemlieck manuver on a choking person the object in their throat usually pops out with quite a bit of force.) Anyways all that pressure build up plus the inital object that was stuck cause some lasting soreness, but it should be gone within a day at most! | bf5609dd-ee72-4595-8588-5a600af335d0 |
c0u5qd | the Casimir effect | > the Wikipedia sounds like technical gibberish.
That is often the case with quantum physics, but luckily it can be simplified greatly. The big difference between quantum physics and classical physics is the idea that the behavior of the universe can be described in "quanta" (plural of "quantum"), the minimum amount of a physical entity involved in an interaction. While classical physics would say that I could push on a box, then push on the box half as hard, then keep cutting that push's strength in half forever, quantum physics would say that there is some minimum amount of push that could ever take place. That smallest amount would be a quantum, an indivisible unit of interaction.
One of the fundamental properties of the universe is the idea of an electromagnetic field that extends across all of reality. This field is what carries disturbances called electromagnetic waves (light, radio waves, magnetism, etc.), and the force carrier for this field is called a "photon".
It is also theorized that this electromagnetic field has a net positive amount of energy even in a complete vacuum. This "vacuum energy" is the result of oscillations of the electromagnetic field that average out to nothing on the large scale (cancelling each other out) but are always fluctuating.
What the Casimir effect demonstrates is that if you take two uncharged conductive plates and place them very close together you can create a space where electromagnetic waves of too great a size cannot fit due to the limitations in the quanta of the electromagnetic field. Only photons which have a wavelength that will fit an even number of times into the gap should form part of the vacuum energy, and so the vacuum energy between the plates should be less than that of the ambient vacuum resulting in an apparent attractive force between the plates (really a compressive force from outside vacuum energy). | ab7286a7-d647-4ec0-9dc0-3e0ffd2b8410 |
c0umf4 | Why isn't there a bigger engine with more cylinders than a V12? Is it possible to build a V14 and so on? | Just because you've never heard of it doesn't mean it doesn't exist | fb2dfddf-92df-4d65-9a05-e86f24a50b07 |
c0un2w | How can I access and stay connected to WiFi while inside an airplane thousands of feet in the sky? | A satellite beams Internet to the plane which has routers and access points. It also acts as a mid-point for whatever information you send to the Internet. Ground based antennas work too, if they're available. | 5f47cd0e-7184-47f3-b83d-8020f497b069 |
c0uxci | What is stoicism and what is the difference between ancient stoicism and modern stoicism? | A stoic would suppress feelings, to the point of not overtly reacting to very difficult situations. I’m guessing an old school stoic just sets plans for the next adventure, a modern stoic finds the next brewery with better happy hour prices | 21f8855c-4787-4b8a-b411-d7ef1407683f |
c0uyem | How do stomach aches work anatomically? What’s the science behind the pain they cause? | The pizza gods get angry if you consume too much of their children so they curse you temporarily with pain. | 68620bea-fb7c-4a6a-9cb8-38a168636e61 |
c0v37f | IUDs... I understand what they’re used for, that there are two kinds, but I want to know how/why they work. What is the mechanism behind them and how do they act as a contraceptive? | **Hormonal IUD:** These work by messing with your hormones just enough so that your ovaries don't release eggs when it's time to ovulate. Depending on IUD, it may not prevent the ovaries from ovulating. Another way, then, is that the hormonal IUD thickens the mucus in your uterus, thereby slowing down sperm. It's like asking someone to swim across a pool of water versus a pool of honey. The thickened mucus makes it harder for the sperm to "cross the pool" to the egg.
**Copper IUD:** Sperm don't like copper and die when there's too much copper in the uterus. In fact, the copper sort of "decapitates" the sperm. It's like Gandalf saying, "You shall not pass!" The egg's still there, but the sperm can't get to the egg because the copper's killing them off in their journey.
So one acts on egg-release in the ovaries, and the other acts on sperm that try to swim to those eggs. | df31d43b-f048-43db-a0ca-0d41cbfd457d |
c0v8ms | why are some places called "new < another place > " after other places? | Historical context, some examples below....
Basically the name could be in honor of someone or something, or merely derived from specific events in history.
& #x200B;
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Or the place may be named New "Place" due to historical context. Example below for New Orleans:
" Founded in 1718 and named for the Duke of Orleans, from the start La Nouvelle-Orléans viewed itself as a city apart from, even superior to, other New World settlements. Proud of its French pedigree even after France cut the ties and sold Louisiana to America, New Orleans maintains a slew of French-influenced cultural and gastronomic traditions."
Reference: [_URL_0_](_URL_0_)
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Or you might have something where people from the "other place" wished to make a create another city resemble the "other place," or with similar characteristics.
Reference:
[_URL_1_](_URL_1_) | 86b1b0bf-4691-4c4d-9fd0-8ba6aa0fb154 |
c0vnia | The situations currently occurring in Sudan and Hong Kong | Sudan: military stages coup to oust dictator who had been in power for 30+ years. Military said they want democracy, but the people felt like it was a lie and it was just a shift of power instead of introducing democracy. Huge protests since then, military isn't liking people questioning it's authority, resorted to extreme violence.
HK:New extradition bill would allow HK citizens to be extradited to mainland China for "crimes". People concerned it would allow anyone to be disappeared on trumped up charges. Huge protests roughly 1/7 of population demonstrating. Police doing police things and violently trying to surpress protests | 58afe024-5075-48cc-80c4-e9b4a8f648c6 |
c0vo7v | Why do some mice put their babys in the running wheel, let them loose and then start running? | I would assume it’s because they want their young nearby and in sight but have no concept that the ground around them will shift as they run
Or maybe they just want the baby to learn healthy exercise habits early | 71838cb2-70f4-42e5-becc-15dc10b8c801 |
c0vrnn | What would happen if all of the debt in the world was somehow permanently deleted? | It does initially sound wonderful. Until you realize that there are a lot of people in debt to you. For example the money that is in your bank account would be gone as this is money that your bank owes you. Similarly any pension fund or college fund would be wiped out. You paycheck would also be gone as this is money that your employer would pay to settle the debt for the hours you have worked. In any case they would not have the money to pay you as they will not get paid by their customers. But say that you did not want to eliminate smaller debts between people and companies but only national debt. What do you think the bank does with your deposits? They turn right round to the government and loans your money to them. Most of the national debt is either directly or indirectly owed to private citizen of the country. And most of those citizen are the poorer citizens as the richer people can take more risks with their money and loan to companies or individuals. | 4cc11ff7-12eb-4170-a722-d4f20673c8f7 |
c0vzg3 | How is a Portuguese Man O' War actually a combination of different animals? | [This](_URL_4_) is a sea anemone. Basically a pouch with tentacles, right? [Jellyfish](_URL_0_) are basically the same thing but upside down. This kind of animal is called a cnidarian. Many cnidarians are capable of reproducing by budding, as illustrated by [this hydra](_URL_6_). Basically a little replica grows off the parent and eventually pops off, becoming a separate critter.
But what if it never disconnects? Then you get a whole bunch of connected cnidarians. The most famous version of this is [coral](_URL_2_). Basically if you look closely at a coral, you'll find it looks a lot like a ton of teeny tiny little anemones all stuck together. There was an original polyp that produced a bunch more polyps through budding, but instead of splitting up and becoming independent they stayed stuck together.
Essentially, this is how a portugese man O war works. Except while the polyps in a piece of coral all look alike, the ones in a man o war look different from each other. It's maybe easier to understand in some other relatives of the man o war which are more spread-out. [here](_URL_5_) is one such relative. First imagine a coral, but instead of the polyps being all in a kind of lump they are stretched out in a line. Then look, you've got some bell shaped ones on the top with a big body and no tentacles then behind it some ones that are mostly tentacles with a small body. Each specialized to do a job. [this cool video](_URL_1_) explains how they grow. Because a portugese man o war is all jammed together underneath the float, it's a bit harder to see the individual polyps, but [they are there](_URL_3_), lined up beneath the float.
So basically, it's a combination of different animals in the sense that it's built like a bunch of jellyfish or sea anemones stuck together to each other hanging off the bottom of a float, specialized for different tasks like catching food, digesting it, and reproducing. Don't get confused and think they are different species though, they are all genetically identical and budded off the first one in the same way that hydra is budding off the other hydra in the picture I showed earlier. | e1aa48e1-f23a-4e5a-bfcf-30a81f6cf350 |
c0wsee | How do energy drinks give energy? Do they actually work ? | They, aside from an absurd sugar content, are filled with caffeine. Much like coffee, energy drinks have a stimulating and energizing effect. They give you a boost of energy and ward off tiredness.
However, caffeine isn't good for you in large doses or when you're underdeveloped, as it puts some amount of stress on the heart and central nervous system. Energy drinks usually have a *lot* of caffeine, so while they do provide you with a boost of energy and can help you focus or stay awake, you should enjoy them in strict moderation. | 38b58aa5-b999-4d2e-a7cb-645d082c21b7 |
c0wtpg | Is all land in world owned by someone? | Not all land is owned by someone, but it's mostly deserts and disputed areas that nobody wants to own, or have been designated as Terra Nullius.
However, all land within a country is either owned by a private person or the government. There is no area f.i in the US you can simply plop down a house and say "Nobody is here, therefore it is mine".
If you want to acquire an area it depends on who owns that area.
If it's in private ownership you find the owner and purchase it from them.
If it's in public ownership odds are it isn't for sale, but for some areas you can buy it from the government, or if you're really lucky the government treats it as "unclaimed" and you can go trough a land acquisition program to be registered as a legal owner of that land. Methods and programs vary between governments, areas, and districts. | 30896d94-8169-4be4-a045-98fec2665a3b |
c0wzei | Why do passengers on an aircraft have to recline thier seats, pull the windows and stow away thier trays when taxiing, taking off and landing? | If something's going to go wrong on a flight, it's more likely to be during takeoff or landing.
The intention is to have your seat upright and tray table stowed for better protection of impact, and to leave more room so you can quickly exit your row.
The window shades are supposed to be open so first responders can see in to assess damage and rescue, and so you can see out to see if it's safe to exit the aircraft on that side. | 77a67189-df9a-4515-9d85-3ec4dfa12aec |
c0xish | If water makes things slippery, why does licking my fingers make it easier to open plastic bags? | Licking your fingers is taking away the natural oils present there, so there is a less slippery surface to grab the plastic bag with | 2dcb7247-8626-4380-88c3-290c9a065c01 |
c0xoyy | How does refrigerators work? | It takes energy to turn a liquid into a gas. When liquid refrigerant goes inside the coils of the fridge, energy is absorbed by the liquid refrigerant inside the fridge turning it into vapor. The energy came from the air in the fridge, cooling the air down. The refrigerant vapor in the coils goes through a compressor in the back of the fridge (the noisy part of the fridge) turning it back into a liquid. This releases energy outside the fridge. This is why the back of the fridge is warm. The cycle of liquid to vapor to liquid continues over and over again inside the coils. | cd30b1e5-f757-46c0-b310-9c235b8b4b30 |
c0xwge | Do insects have the same sort of internal organs as us? | No, they do not. They have analogous systems, but they can vary wildly in function. For example, the respiratory system of most insects is trachea, not lungs; they do not have a pump that hauls air to and fro, they absorb oxygen by diffusion.
Only vertebrates have truly the same organs as us, because they evolved from the same ancestors as us. Frogs, snakes, birds, cats and dogs and humans all come from the same primitive ancient lungfish which already had familiar internal organs. The arthropods split much earlier, at the worm stage that had barely any organs at all, and evolved independently. | adcccdc1-6544-4de0-868b-84f8c2eb1131 |
c0ya1x | How and why does music sound good? | Short answer: Because you have been programmed with expectations that you enjoy being either fulfilled or subverted.
Long answer: the only universal element in music is the perfect fifth, which is a ratio of frequencies of 3:2. Different cultures have developed different systems of tuning and organization of tones to hang on that foundation, which continue to develop, and borrow from, or spurn each other’s ideas. In the West, you heard nursery rhymes from before you were born, and those simple, boring melodies helped you understand what to expect. New music you hear either fulfills your expectations or surprises you by doing something you might not have expected. Both can make you feel joy, or other emotions. Lyrics lay a whole new layer on top of all this. | ec692145-f59e-4652-943e-66581d87a95a |
c0yd2e | Why do glasses of water with differing volumes emit different pitches when tapped with a spoon? | The differing amount of water in each glass causes the glass to vibrate at different speeds when hit. Sounds are just vibrations, so different speed vibrations make different sounds | d6aad6d8-0a81-4816-951c-fb7bfa4d5dc7 |
c0yhj0 | Cats usually clean/groom their fur right after eating. How is it that they don't end up sticky and smelly from the food they just eat? | Well sticky residue usually is the result of sugar, which there is none of in cat food. And cat breath usually isn’t that bad due to low levels of bacteria in their mouth, so there’s not a lot of smell. | 944c7b87-f302-482d-8367-699fb1474a93 |
c0z97l | How does a fuel pump always know when to stop pumping? | It is not too dissimilar from an air mattress that you blow up with a pump. If you connect a pump to an empty air mattress and turn the pump on the mattress will fill and tighten, or pressurize, with air. Much like your car, when you start the engine the pump begins to pressurize your fuel tank. Imagine you put another valve on the opposite end of the air mattress and begin to let air out through this valve. The pump that you still have running will keep the air mattress pressurized as you let air out on the other side, giving you a fast steady flow of air out. The same thing happens with your car, pressurized fuel flows out into the engine and the pump keeps pumping to keep enough pressure to allow this fuel to keep flowing out. The pump is designed to be able to continuously pump and not get damaged, even if you car is just sitting idling and not using much fuel. There is more magic that makes things more efficient, but that's the gist of it. | 7c458e28-427c-44e5-9ffd-e5108106c72b |
c0zirm | What is the concept of the pecking duck in Chinese cuisine? How did they used to blow into it, before the advent of electric pump or just a pump in general? | With a pump. Pumps have existed for ages before electricity. Leather Baffles or even just using your lungs | 8553a611-7318-4895-b6b0-03a6cfa60bd2 |
c0zizz | Why do seatbelts sometimes lock and get really tight to the point where you cannot move forward | The whole point of a seatbelt is so that you can move around enough while its in place but the event of a crash it locks you in place so you don't jolt forward and get injured more than you normal would | 818f4283-73e9-4546-9884-b750e5aa7ba2 |
c0zlew | Lootboxes in computer games. | To start: Minecraft would no longer give you the option to change skins or texture packs. Instead, you would purchase inecraft loot boxes
Minecraft loot boxes would be 100 Pale Diamonds to obtain. You can get 5 Pale diamonds each time you earn an achievement, and 100 Pale Diamonds when you beat the game. You can also purchase 100 Pale Diamonds in the Minecraft Store for $5 in real life.
When you open a Minecraft lootbox, inside there are different textures for Mobs and Blocks and tools, and even some skins. The textures have different rarities. Legendary Skins and Textures are more detailed, with little voxel details.
Mind you, every season would include different available textures for a limited time. If you wanted to play the game with lots of snow textures, you better purchase at least 30 Christmas Minecraft Lootboxes. There is no way to just purchase the texture or skin you want directly, instead you must rely on luck.
A big appeal is showing off your rarest skin as a sign of achievement. And each player can see your armor skins and stuff.
Since you want certain skins, you will either grind the game as much as you can or pay a simple $5 fine.
You pay $5, and you might get the thing you want, so you just pay until you win. That's gambling. | 76466a3a-7256-4264-bb84-8713722ebeee |
c0zoce | Why do toothpastes advertise being fluoride free (therefore better) when dentists prescribe fluoride toothpaste for teeth sensitivity? | Because they are marketing to a fringe market of people who believe fluoride is added to water to poison people (it isn't). These tend to be the same people who believe vaccination is bad for you, that cures for diseases are suppressed by pharmaceutical companies, and all sorts of other nonsense conspiracy theories.
Fluoride binds with calcium in teeth/bones to produce a mineral which is very resistant to breakdown. So if you're a child who is growing permanent teeth and you drink water with fluoride in it, as your teeth develop fluoride is incorporated into the adult tooth. The result is reduced likelihood for cavities for the lifetime of the tooth. This is different from mouthwash/toothpaste fluoride, which acts only on the surface of teeth.
Like all decisions that are made to protect public health, it's a trade-off. You minimize the harms as much as possible and maximize the benefit, which is why the amounts added are very low where it's virtually impossible someone would get a toxic/harmful dose from drinking tap water.
Edit: Unrelated note, but some countries/regions do not fluoridate their water, they fluoridate their salt because salt is used in cooking universally in those areas. Just an interesting variation that shows you how a lot of thinking goes into this type of action. | eea3f34d-ff3b-48e9-b0f6-a7295c8489c9 |
c0zoqr | Gold as currency historically | It is a combination of a few reasons. One of them is scarcity. Gold is a rare metal in Earth when compared to other metals such as iron and tin. Another reason is that chemicals speaking it is incredibly stable. Gold does not corrode when left exposed too air. That makes it great for coinage and jewellery especially before things like air conditioners and weather sealed rooms became a thing. You can leave a gold coin out in the rain for years and it will still be relatively the same. Gold is also a very soft metal. Which makes it easy to work with and mold to whatever shape you want it to be. And last but not least, it's shiny and a different color than most of the other shiny metals so easily recognizable as gold.
Edit: stupid auto correct | 955c96a4-5c7d-40f5-9c5e-8a0e06331bcc |
c0zx1x | We figure out the chemical compositions of stars by looking at their wavelengths, but wouldn't this be influenced by red shift? | Yes, absolutely! But the spectra of the elements within stars aren't just single peaks, they are a series of peaks at very specific wavelengths and spacing. If the star's spectra is shifted (as they usually are) the characteristic pattern can still be detected and the amount of shift then used to calculate the relative movement of said star. | 19ac653c-4501-4aba-8990-29ce6a7b08e7 |
c10chg | SRS Surgery | * r/MtF
* r/asktransgender
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* Yes, you are under general anesthetic for the entire procedure.
* Yes, there will be lots of pain. Especially the days after the surgery and the maintenance work you have to do afterwards so that it doesn't grow together again.
* The surgery can take anything between 4 and 16 hours depending on method, surgeon and personal factors.
* What exactly they do depends on technique and surgeon. I can't really write that here, though, for NSFW reasons. | 7633ee22-556c-497e-904d-dc670c11ece5 |
c10cup | Other than ownership, what are the differences between an apartment and a condo? | Ownership is really the only real difference. That said, in a condo building, there’s usually some kind of owners’ association where the residents as a whole are members and pay dues and the association has the responsibility of taking care of the outside of the building and sometimes minor internal repairs. | 8d853c01-19ff-45e3-ad77-4dcdd5af241f |
c10ofn | Which variables, both on the buyer and sellers’ side, are most critical when deciding between a vehicle lease, or purchase? | You are correct that is isn't black and white but more than just the cost of the lease itself. If you lease a vehicle you have something very important - liquid capital.
If you are a business you can use that money to invest in your company. If you are an individual you can invest the money, put it in savings, pay off other debts or just buy something that makes you happy, which has intangible value.
As consumers we tend to not to see money in the bank today as more valuable than money we will have to pay back in the future. Which of course it is if you can make a return on that money. | 2fc29481-bc77-4765-ba39-3c47553407af |
c10q8f | Lighting strikes a body of water, like a lake or a swimming pool. Does everything in the water die instantly? Chances of survival? What's the size/diameter of the kill zone? Does the energy disperse in the water the further it gets from the strike point? | I don't know if organisms in the water die instantly or whether they survive but this post is pretty similar
[_URL_1_](_URL_0_) | 8310d9b9-f1f9-4635-98ce-d0b61fa97e09 |
c10tpt | why is pee yellow and if you drink a lot of water why is it clear | Normal **urine color** ranges from pale yellow to deep amber — the result of a pigment called urochrome and how diluted or concentrated the **urine** is. Pigments and other compounds in certain foods and medications can change your **urine color**.
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[_URL_0_](_URL_0_) | c8226c65-ddfa-4f65-b663-b25535a05a2a |
c111un | why computer networking cables (ie cat5e) need four pairs of wires when the dsl that feeds my home only uses a single pair? | Your DSL is relatively slow, most DSL tops out at 10s of Mbps
100 Mbps ethernet uses two pairs of wires (one pair for talking, the other for receiving), while 1000 Mbps ethernet uses all four pairs (two talking and two receiving). Four twisted pairs in CAT5e supports up to 5 Gbps, about 50x more than the two wires in your DSL line with just 4x the number of wires.
CAT5 and CAT6 have 4 twisted pairs because it greatly reduces noise and allows for really high speed communication so you don't have to upgrade all your cabling every time standards enable higher bandwidth. | f6ec0819-e4a9-4192-b0ba-dc3113169c56 |
c1133o | How/why do butterflies have such an irratic flight pattern? | Sure seems to be a self defense mechanism to avoid predators, namely birds. Birds can change direction on a dime like a butterfly. Still, birds got to eat and the defense is not perfect. | e7b5a9ce-1d4e-46a5-916d-4b6d8afbdfae |
c11h5s | how music is read on cds and cassettes | To put it simply, any information (text, sound, video, math, pictures, etc) can be written in binary code, AKA Zeros-and-ones. How those 0s and 1s are translated back into a sound or an image depends on how they are translated, and by what or who is doing the translating.
Think of it this way: if i gave you a book that said 000=A, 111=B, 010=C, what would 010 000 111 spell? It would spell "Cab".
Now, lets say that book also contained 01 codes for every musical note, at every pitch, played by every known instrument and every electronic synthesizer, and then handed you a scroll filled with millions upon millions of 0s and 1s. Could you eventually translate them into sheet music? Theoretically, so long as you didnt kill yourself before completion, yes you absolutely could.
Then the sheet music could be played by an orchestra. TAdaaaa! Binary code to real, listenable music.
A CD player does this in a matter of thousandths of a second. A laser skims the bottom of a CD and there are microscopic divets and bumps on the CD. A bump is seen as a 1, a divet is seen as a 0. The laser reacts every time it hits one of these, telling the cd player's processor that 0s and 1s are coming in en masse. That computer inside the player then translates these in essentially real-time to the audio that is played out of the speakers. Yes, it's impressive as fuck of a technology, especially considering its completely obsolete at this point and yet still so mindboggling to comptehend how humans figured it out in the first place.
Tape works the same way. Just instead of a laser hitting bumps, a magnet reacts to polarity push or pull on the tape as 1 or 0.
Thats the magic of binary; 1 or 0, on or off, red or blue, bump or divet, car or train, apple or orange... it doesnt matter. 2 values can be used to code out literally any and all informatiokn so long as there's a way to translate it back. | d9e2fc8f-34f7-4ab9-b86a-007a33ad5995 |
c11hf4 | How does the tilt-up and tilt-down dimming feature in a car's rearview mirror work? | The way it works is that the mirror and the front glass are arranged at an angle to one another.
\|
If you imagine the above represents the mirror side on, with the glass at an angle, and the mirror itself flat.
This is the mode you'd be in driving normally.
At night if you've got someone behind you dazzling, you'd switch the mirror so it's like this:
|/
Now the glass is providing the reflection, and the mirror is reflecting a section of the interior of the car.
Glass is reflective. Not very reflective, but reflective nontheless. Say for example it's 15% reflective and 85% transparent.
The reflection you'd see of the interior upholstry is indeed there, but it's so dim that the light you're seeing reflected off the glass (even if it is only 15% of the light) beats it.
It's the same reason if you're inside a house at night, and you have the lights on, if you look out the window, you'll likely see a (dim) reflection of the inside of the house instead of the nighttime scene outside. | dfe94b00-9275-480e-8630-e32937b661c5 |
c11jog | How and why does the time of the day affect our emotions? | At night, you're tired and ready to call it a day. You let your guard down which opens you up to those kinds of thoughts and feelings. You aren't required to be alert in bed like you are during the day at work or school. | 920eb901-fce5-49a2-b596-bc947755205e |
c11ksf | Does squinting actually help us see better or is it another brain trick? | it does help. a smaller aperture on your eyes results in less light, but also in a sharper image as it reduces "spherical abberations".
you don't need to squint, you can also make a small home with your fingers. | d2d1f725-389a-4624-85ff-becc47450134 |
c11olg | How do toilets keep a consistent water level? | The bottom of the toilet is shaped like a “U”, so fills with water. If any more water is added, it overflows over the back into the drain. | d01c525a-09df-4495-8899-a19cc61ae799 |
c11qjo | How does hand sanitizer kill bacteria cells but not our own skin cells? | The epidermis layer of the skin is made of dead skin cells. So the sanitizer cannot kill what is already dead. It does not penetrate further down into live cells. | d242bb64-c8ad-444b-89a2-14f3920e1ed4 |
c11spt | Why is it that our internal temperature is 98.6 degrees, but if we touch something that is around that temperature we burn? | I beleive you may be getting farenheit and celcius confused. A hot tub, for example, is around 105 degrees farenheit. While on the other hand 100 degrees celcius is boiling tempurature for water, which our body is mostly made up of, so it would burn you. | 8bf0720e-0e60-44a7-9206-05bf9f09d246 |
c11vl6 | Can you fingerprint be changed by a cut? | I’m not sure of the actual specifics on whether or not it can be “recreated” after an injury or cut. However, I have cut the top left corner of my left thumb nearly off before with an accidental slip of an Exacto Knife and I can tell you that fingerprint scanners on phones or similar will not recognize that area of my thumb anymore if attempting to log in.
No idea if this is just coincidence or if it is actually damaged from the cut itself. | bc86a229-6fd0-43b6-87a1-73eb2b70a67c |
c126g0 | How does a bootstrap paradox work? | Suppose you travel back in time with the knowledge of some invention which exists in your time (transparent aluminum, perhaps). You visit the inventor of that technology and tell them what you know. They go on to "invent" it just as history told you they did. But you now realise that the inventor only ever knew how to invent it because you told him. So there's no "beginning" for the knowledge - you learned it from the inventor, and the inventor learned it from you. | 10375c68-4271-4a70-b8b2-84b43c6609dd |
c12fhn | how does the brain suppress the sound sleeping people make themselves. | Because they are used to it. If you sleep with someone else who has a snoring problem, you will eventually get used to it because you hear it every night. Talking from experience | 3c95a1a0-13fc-4b52-a507-42ad6e140dc7 |
c12ivn | How are there different seasons on opposite sides of the earth? | There was a man with big, round belly. On his belly button, which was right in the middle of his belly, all around the man was a line. The same like the equator on Earth. Up from the line was north and below the line of his belly button was the south.
The man had a desk with candle that shined right on his belly button.
The belly button was warm and happy thanks to the candle. Man leaned to the desk, to reach for the glass with water that was there. His belly button went down with his belly and now the candle shined to the up of his belly. That was the north. And top of the man belly was now in the light and warm and happy. This was the summer north.
Below his belly now was darker. And there was colder. It was winter on the south. Which was below his belly button now in the dark.
But then the man raised his glass and tipped back to drink.
And it was different now on his belly. The bottom was full of light, warm thanks to candle. Dinner on the south
And the top of his belly now was darker. Winter in the north. | dc7391d9-0790-4bed-91bd-956f5b0d628c |
c12jlx | Why does food lose its taste when you're crying? | Crying plugs up your sinuses so you can't really smell anything. Smell is a very large component to taste. | 0b4e52fc-3cc9-4081-a500-d08509bb405b |
c12o31 | City skies appear fuzzy because of air pollution, but why do some rural skies appear black with stars while others appear bright blue during nighttime? | Fine water droplets (thin clouds, mist or haze) also scatter and reflect light and can form in both rural and urban areas. Depending on altitude and local conditions they can scatter distant city lights or moonlight. A lot will depend on local topography, temperature and winds. | 5c7041f2-38a6-4353-9f8c-636c54cdf12f |
c12th1 | - why/how does lint collect in bellybutton? | When seen through a microscope, your hairs all are very serrated, making them grabby towards any fabric. Elsewhere on your body, you don't notice the fabric being pulled out because it doesn't have anywhere to collect. Not so with a belly button. | c7eb051e-9278-4857-8bc7-c4275b73b621 |
c1314k | How does inflation work? And how do business know when to adjust their prices to that? I guess banks don't shout out:"We just printed another 1b$ that will be in circulation soon, so make sure to increase your prices accordingly"? | To understand inflation, you first need to understand the difference between money/currency & wealth.
We create wealth all of the time. Let's say you pay $1 million to mine materials out of the ground & you sell those materials for a profit. That profit is new wealth that you created. Then someone could buy a bunch of materials & pay workers to create a product that they'll also sell with a profit, creating even more wealth. We create wealth with human work (physical or intellectual) & from natural resources.
Now, if you continue to create wealth, but your amount of currency stays the same, then the value of that currency will increase. People will want to trade more currency than there is, so currency will become rare & the value of that currency will increase over time. That's deflation & it's bad because it becomes more profitable to keep your money rather than invest it. And without investment, you can't create as much wealth.
So, the solution is to print more currency as wealth increases in your country. The ideal goal would be to print the exact amount of currency as your country creates in new wealth. The problem is that it's hard to estimate the exact amount of wealth that'll be created, so you can't print the exact amount of currency you need.
The value of your currency depends on the law of supply & demand. Your production of currency is the supply of that currency. And the amount of wealth you create is the demand. If you over-produce your currency, then you have a higher supply, so your demand/the value of your currency decreases over time. If you under-produce your currency, then it's what's said above: you'll have a lower supply of currency than the demand (wealth), so your currency will increase in value.
So, now you have a choice. You know you can't produce the exact right amount of currency, so you can either over-produce currency, which creates inflation, or under-produce currency, which leads to deflation. The solution is that a little bit of inflation is better than a little bit of deflation, because a little bit of deflation still incentivizes people to keep their money, while a little bit of inflation incentivizes people to invest their money, & investment is an engine of economic growth. | c01c8879-471a-48c5-adac-5dab00c5f27d |
c137q2 | Why there are only spherical planets and we don't see other shapes across space | When a object is large enough the force of gravity shape it like a sphere.
Gravity is always to the center of mass and the force. If you had a cube there would be more material towards and pressure on the stuff below would be higher then for the stuff below the middle of the flat area. The result is that the material move toward the location with lower pressure. So the corners start to move toward the center of the planet at the same time as the flat middle areas would rise and move away. That would happen until the pressure start to be very close to equal everywhere at the same distance from the core. That shape will be very close to a perfect sphere.
& #x200B;
The pressure is so high that no material can keep the shape if the pressure is not equal around it. The pressure at the core of earth is 3 million times atmospheric pressure. So the material the behave a lot more like play-doh/clay so when you manipulate it and not as rock.
So nothing that would be planet shape could be a cube because it would collapse to a ball because of gravity. | a5fa48c7-5910-41d4-ac39-37950f9d6c85 |
c13ba1 | What is a bone marrow transplant? | Not quite. Before the recipient gets the new marrow, their defective marrow is destroyed using radiation or chemotherapy. It used to be that some of the donor's bone marrow is extracted from the pelvis using a large needle, but now the more common method is something a called peripheral stem cell transplant, which is less invasive than extracting marrow from the pelvis with a needle. In a peripheral stem cell transplant, the donor is hooked up to a machine using a simple IV. The machine filters the donors blood and removes hematopoetic stem cells (stem cells that will produce all types of blood) while returning everything else back to the donor. Then these stem cells are injected into their bloodstream of the recipient. From there, the cells will circulate and make their way to the recipients bone marrow where they will proliferate and being producing normal blood cells for the recipient. | bb7ed2fe-592e-4d5e-bada-3693150e4bbc |
c13bu9 | Why are there no guns with more effective explosives than gunpowder? | I think you are seriously mistaken. Firearms haven't used gunpowder since [cordite](_URL_0_) AKA smokeless powder was invented in the late 19th century.
The only guns you'll find today that use actual black powder are antique and replica muzzle-loading rifles. | cde367cd-186a-47ad-9e3e-15c756fd3b84 |
c13hdv | Horseshoes. What do they do? How do they work? What happens/happened to horses feet without them? | Horse hooves are large pieces of keratin, same as your nails. Keratin is moderately tough and horses adapted it to suit the arid-steppe climate, but not suitable for hard, rocky or wet surfaces or continuous running like we used them for.
Horseshoes are pieces of metal or some other hard material which is nailed into the horse hoof. It doesn’t hurt if done properly, since the hoof is basically a giant nail and has no nerves. The horseshoe takes the punishment for the hoof, so the hooves don’t get damaged as much and split/crack.
Broken hooves are terrible. They can become infected, cause even more cracks, and/or cause great pain for the horse. Horseshoes prevent that. | bf88295c-9415-4da1-a959-31c6bd3f2233 |
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