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6mimi2
Why do babies eat anything, then become extremely picky, then slowly start having a wider palette again?
Biology
explainlikeimfive
[ "dk1wfgf", "dk1vkhl", "dk2hlk9", "dk26ttj", "dk2hd4b", "dk2czyu", "dk2hfon", "dk1x0kx", "dk2hmyh" ]
[ "Everything you're giving them is a flavor explosion they have yet to experience, outside of breast milk or formula. As you feed them more things, they discover that \"Hey, this thing is my favorite so far\" and since they're babies...they don't want the mashed broccoli anymore, they only want the apple strawberry sauce. Food, especially less sweet ones, take multiple time for the palette to acquire a favorable taste, which expand as we grow." ]
[ 206 ]
[ [], [], [ "http://www.ellynsatterinstitute.org/dor/divisionofresponsibilityinfeeding.php", "https://www.ellynsatterinstitute.org", "http://www.prevention.com/food/healthy-eating-tips/new-gene-variant-identified-makes-vegetables-taste-bitter" ], [], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
abo8pb
How can paint exist permanently as a liquid in the can, and then permanently as a solid on the wall?
Chemistry
explainlikeimfive
[ "ed1t97o" ]
[ "Paint contains solvents to keep it a liquid. When the solvents evaporate the paint dries out and hardens. The sealed lid on the can helps slow the evaporation process as long as the can is relatively full." ]
[ 24 ]
[ [] ]
[ "url" ]
[ "url" ]
moe8gf
How can a blanket full of holes (think crochet etc) keep you so warm?
Growing up we had quite a few crocheted blankets we’d use and despite being literally full of holes, I’d often put my toes through them, they were the warmest blankets.
Physics
explainlikeimfive
[ "gu36b4y", "gu3av8w" ]
[ "it’s the love they were made with that keep you warm. plus trapping the warm air in the between the stitchings is of assistance. machine made blankets only keep robots warm." ]
[ 19 ]
[ [], [] ]
[ "url" ]
[ "url" ]
hpps2i
how you define exactly what one calorie is, and why we measure food that way?
Chemistry
explainlikeimfive
[ "fxt1ied", "fxt3nm7" ]
[ "A calorie is the amount of energy it takes to raise the temperature of one gram of water by one degree Celsius. It is a useful unit of measurement for energy. It comes from science, and is not exclusive to food. The Calorie on food labels is actually a kilocalorie (1000 calories) which is confusing but ultimately easy to distinguish once you know what to look for. Capital C Calorie is 1000 calories. Little c calorie is a true calorie We measure food energy content that way because it happens to be an appropriately-sized energy unit." ]
[ 26 ]
[ [], [] ]
[ "url" ]
[ "url" ]
hqy4z4
Where do certain insects get their energy from if they don't eat and their sole purpose is just to reproduce and die?
Biology
explainlikeimfive
[ "fy0q950", "fy0qdgs" ]
[ "1. I do not believe there are any insects that do not eat. As you noted, this violates basic laws. Everything requires an energy source and no insects can live without food or HAVING eaten in the past. (There are some insects that do not eat in late stages because they ate and stored enough energy in their young forms and this is also why they have a short life span as adults) 2. What is the point of anything's existence? Simply because it does. Humans have no real reason to exist either. This question is not answerable. 3. They are part of an ecosystem, but they are not actively contributing to the environment. Greta Thunbeetle does not exist. They just live to reproduce and that's it. The rest of ecology moulds itself around life, not the other way around." ]
[ 9 ]
[ [], [] ]
[ "url" ]
[ "url" ]
jq3g5z
Why can’t airplanes get into space?
Engineering
explainlikeimfive
[ "gbjax13", "gbjbag8", "gbjc8e8", "gbjat6b", "gbjfrcn", "gbjgw54", "gbjedrg" ]
[ "Airplanes require airflow to generate lift under the wings. After the air thins to a certain point, the plane can't go any higher" ]
[ 87 ]
[ [], [], [ "https://youtu.be/Zu-Sp3I0c1Q" ], [], [ "http://fenewsnet.com/wp-content/uploads/2018/07/Flat-Earth-Rocket-Curve-Not_Hit_Dome.jpg" ], [], [] ]
[ "url" ]
[ "url" ]
f5ufrn
Why does the Tyrannosaurus Rex have tiny arms?
Biology
explainlikeimfive
[ "fi0sdiv" ]
[ "Short answer: evolution. Longer answer: longer arms weren't necessary for it to thrive, might have thrown off its gait, and are metabolically less expensive (uses less energy) than big arms. So T-rexes with short arms won out in natural selection." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
9j2zyr
How are nitrogen filled car tires more fuel efficient than normally filled tires?
Chemistry
explainlikeimfive
[ "e6o8ghb", "e6o7vxx", "e6o95lj" ]
[ "In average joe world, it has no real measureable effect. In racing world where times are measured in tenths or hundredth of a second, it makes a difference in consistency and predictability of pressure and tire performance. So why do vendors do it? Because it's minimal cost and avg joe consumers are gullible into thinking it's a premium product, so there's more customer retention for future purchases." ]
[ 12 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
a7153c
Why do people snore?
Biology
explainlikeimfive
[ "ebzsqub" ]
[ "In some sleep positions with a relaxed throat there's a bit of catching the air, getting stretched, then releasing that self reinforces to create a steady deep sound. Just like the intentional version when we partially block the air path with out vocal chords that just vibrate at a higher frequency, or like rolling your Rs with the tongue on the roof of your mouth." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
7ohat6
Terminal Illness Discovery
How do people that find out they only have a specific limited time left to live progress to finding that out? Like what typically starts someone down the road of discovering a terminal Illness? Are there extremely common tells like high white blood cell counts or something like that? I've grown up being a pretty intense hypochondriac. I hear of any person, personally known or indirectly known, with a certain medical issue and instantly begin to worry I have, or will get the same thing. And then start worrying and speculating about other, entirely different things. Are there things that can be done on a routine basis that is likely to detect the on set of a terminal Illness?
Biology
explainlikeimfive
[ "ds9w8rq" ]
[ "It really depends on the terminal illness. Many times they are found by accident: you go to the ER with a kidney stone and the CT shows something growing on your pancreas. Sometimes it shows up on blood work: you might go in for a routine checkup and have your blood show leukemia. Sometimes it presents as a vague symptom: your doc does a chest x-ray for persistent cough and finds lung cancer. The big symptoms you are looking for are fatigue, night sweats, and unexplained weight loss. But not every terminal illness causes these and not everyone with these symptoms has a terminal illness. The biggest thing is managing risk factors. Don't smoke. Get all screening tests done. Don't smoke. Eat healthy and exercise. Also, don't smoke." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
jq9m87
Nuclear energy
Other
explainlikeimfive
[ "gblemvs" ]
[ "Power plants that run of fossil fuel produce a lot of carbon dioxide in the process of generating energy. Nuclear power plants do not - however, there's a byproduct of radioactive waste that needs to be stored securely. Nuclear energy is clean in the sense that it doesn't cause nearly as much carbon emissions as burning coal does, but that doesn't mean it's entirely clean or without downsides. It's very clean relative to some other methods of consistently producing energy." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
6vchto
Why are people who witnessed their father beating their mother as a child more likely to beat their own wife?
Biology
explainlikeimfive
[ "dlz63p7", "dlz5sy6", "dlz60v0" ]
[ "People assume certain things as \"normal\" until proven otherwise. When a child is raised in an environment with domestic violence, they will end up thinking that this is how a \"normal\" relationship should be. It's not like they have another reference point because this is their only immediate family. Many of the things happening within a family are only seen by the family. Thus, the son who sees his father beating their mother grows up to think that beating his wife is a normal part of a relationship that does not need any questioning. Likewise, the daughter who sees her mother beat believes being abused as a wife is not anything worth reporting because it is \"normal\". Domestic violence is not limited to male on female so the roles described above can be switched or mixed." ]
[ 10 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
7lqmep
What effect does Chromatic Abberation have on our perception of depth?
Biology
explainlikeimfive
[ "drok4uo" ]
[ "Chromatic aberration is the separation of light by color, the red image is shifted a little relative to the blue image (in the simple ELI5 case where the scene is made of only red and blue things). Human perception of depth is not mostly a color phenomenon, so it doesn't seem like this would make any difference at all. In cases of \"normal\" CA, caused by imperfect lens choices, the edges might be a little less distinct because the red image is shifted a little. This might make purple balls have unclear edges when you examine them in detail. Again, depth perception isn't a detail process, but if you were examining photographs you might think it would impact things. The human eye+brain is an awesome piece of hardware image processing. It's not like cameras and computer stuff. All these answers are totally different if you're talking about computer vision and factory depth measurement." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
mcr24h
How do they put sand inside those full/solid glass hourglasses?
Other
explainlikeimfive
[ "gs52x7z" ]
[ "When they're made there's a hole on the top and the bottom. Notice how almost all hourglasses have something covering the top and the bottom? They're mainly there to cover that hole. It's also possible to melt the glass again and close up that hole, but hardly anyone bothers with that." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
aeh9w4
Trying to explain "fickle" to a friend
Dictionary definitions aren't working.
Other
explainlikeimfive
[ "edp93ys" ]
[ "Inconsistent. \"Hot and cold\". You never know how they'll react to something. Sometimes they're your best friend, sometimes they're antagonistic." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
bxe4n2
The purpose/use of the speculations of computers/laptops.
I've always just seen the most mainstream processors or the most popular graphics card to use but little do you know, I have no idea what their functions are and their purpose.
Technology
explainlikeimfive
[ "eq5p0bj" ]
[ "If you're talking about [speculative execution]( URL_1 ), its purpose is to speed up processors. Processors are actually doing many things at a time in a process called pipelining. A common analogy is [laundry]( URL_0 ) - if you're trying to do many loads of laundry in one set of machines, you could wash, dry, and fold an entire load before moving on to the next one, but then you'd be wasting time. To speed up the process, you can wash one load, and then once it's drying start washing the second load. Because you have multiple resources available to you, you can cut the total time to do your four loads of laundry by having multiple things going on in parallel. Processors do this because, most of the time, it lets you speed up the processor by a lot. Instructions are broken into pieces (e.g. get the instruction, do all memory operations, do all arithmetic operations, do all write operations). By allowing multiple instructions to be happening at the same time, you can have each sub-step be faster, allowing you to increase your clock speed. However, there comes an issue when instructions depend on past instructions. For example, if you do one thing when some value is positive, and something else once it's negative, you have to first wait for that value to be calculated before deciding which action to do. One solution is just to leave a gap in the pipeline, and waste a few cycles. Naturally, CPU designers didn't want to do this, and this is where speculative execution comes in. The CPU makes an informed guess of what the result will probably be, and then starts doing those actions. For example, it'll just guess that the value turned out less than 0, and goes on to do that. If the prediction was correct, great! The speculative work turns out to have been useful. However, if the prediction was wrong, the CPU has to switch tracks, and throw away the work. We lose those cycles, but on average we'll be doing faster than if we had left the pipeline empty, so it's a net win. The better the prediction, the better the win. What researchers have recently discovered is that this work was not fully discarded. It turns out that the CPU, while doing the speculation, left behind small traces that could then be used by the program to extract information it shouldn't be allowed to know. It takes advantage that a lot of protections are built into software, while the speculation happens on the CPU, bypassing protections in the software until the program 'catches up' to the speculation." ]
[ 5 ]
[ [ "https://cs.stanford.edu/people/eroberts/courses/soco/projects/risc/pipelining/index.html", "https://en.wikipedia.org/wiki/Speculative_execution" ] ]
[ "url" ]
[ "url" ]
ipjysp
Why Does Rubbing Your Temples and Head Feel So Good, Especially After A Long Stressful Day?
Biology
explainlikeimfive
[ "g4kdk5b" ]
[ "Tension in the muscles of your face, jaw and neck during the day (due to stress) leads to a low level pain or discomfort that can be relieved by massaging those muscles. Probably is worse if you have a tendency to clench your teeth." ]
[ 9 ]
[ [] ]
[ "url" ]
[ "url" ]
mupml3
Why do bigger animals have more cells than smaller animals instead of bigger cells?
It would be so much easier to just look at a big whale cell than humans having to invent microscopes, y’know?
Biology
explainlikeimfive
[ "gv73icn" ]
[ "Because cells can only grow so big before they become inefficient - it’s more efficient to transfer oxygen between cells with a specialized cell than to rely on oxygen passively diffusing through a giant cell." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
hn8n6d
Why do topical ointments work on every body part but not the fingers/palms that run it in?
Not sure if I worded that well. Topical ointments like Icy Hot. When you run them on a part of your body, like your shoulder, your shoulder feels the effects. But the fingers/ palm that rubbed it in doesn’t feel the same effects. How does that happen?
Chemistry
explainlikeimfive
[ "fx9uoi7" ]
[ "So you typically apply these things where you feel pain. How icy hot works is it essentially \"tricks\" your brain into feeling the effects of the icy hot, making it kinda ignore or forget the pain you were feeling before. I hope that makes sense." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
7ru819
Why do humans have different voices?
Biology
explainlikeimfive
[ "dszmqo1", "dsznk7t" ]
[ "Animals sound different. You just might not notice unless you spend plenty of time with them or are one of them. My dogs sound different from each other and strays. Same with my cats. People that study animals can tell them apart even better than me." ]
[ 7 ]
[ [], [] ]
[ "url" ]
[ "url" ]
8jxapc
What's vasectomy?
Biology
explainlikeimfive
[ "dz35vxq" ]
[ "You could google it, but ill explain anyway. A vasectomy is a surgical proceedure that basically cuts then seals the tubes that lets sperm flow from the testes and out from the penis. Basically permanent contraception for men." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
kgw7f4
How do network monitoring systems like SolarWinds work?
ELI5: How do network monitoring systems like SolarWinds work? What is network monitoring?
Technology
explainlikeimfive
[ "ggi7krb" ]
[ "Let's say you have a company intranet. All your workers' computers are hooked to it, and it's not connected to the Internet. You have lots of servers with websites of proprietary company information, and everything is cool. But, all those workers wish they could watch cat videos on YouTube. You don't just want to connect your company to the Internet, because there are lots of evildoers on the Internet. But the employees complain and complain about their lack of cat videos, and eventually the company gets a new CIO who decides to connect to the Internet. The company could just reprogram all those internal websites to check credentials, but that would cost a lot and was a big reason the former CIO didn't want to connect, no matter how great cat videos are. Along comes a company that says \"Just buy our box and put it on your network. We'll implement 'single sign on' two-factor identity services for all your workers, and you just add the same tiny bit of code to all your servers to check for our identity token. It will be seamless, and you'll be super secure\". Maybe you take heart that the US Government has required everybody to implement TFA, and this company has 400+ Fortune 500 customers. The New CIO buys the box, hooks it up, and everything is cool except the company that makes the box gets hacked and now the evildoers have unfettered access to all your company systems with no records of a break-in or even a logon. Too bad, cat videos are cool but the New CIO gets executed in the parking lot at dawn. A cautionary tale." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
gkkre0
Are streets 100% microbially sterile on sunny days due to the heat + UV rays?
Biology
explainlikeimfive
[ "fqro9e4", "fqroif7" ]
[ "No, streets are not sterile... Maybe if you heated it to incredibly extreme temperatures. But the existence of the sun doesnt make it sterile. Roads are filthy. Make sure you wash out any cut you obtain, especially if its from a road." ]
[ 8 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6pz9dh
Before the advances in dental surgery, how did people deal with wisdom teeth?
Biology
explainlikeimfive
[ "dktbvoe", "dktc0bx", "dkte1r7", "dktpq14" ]
[ "1) live with chronic tooth pain and infection until you die 2) pull it with rudimentary tools. Pray you don't get an infection.....or you could die" ]
[ 26 ]
[ [], [], [ "https://www.sciencealert.com/no-you-probably-don-t-need-to-get-your-wisdom-teeth-removed-ever" ], [] ]
[ "url" ]
[ "url" ]
5z738o
How does Flint, MI still not have clean water?
Other
explainlikeimfive
[ "devsbhe", "dew1c01", "devs9yj", "devryvc", "dew4j8m", "devxk52", "devrzrc", "dew5gnw", "dew81zp" ]
[ "The mistake that led to Flint's toxic water was a water purification error that corrupted the actual *pipes* the water flows through. So the water itself can be perfectly clean, and on the way to your house, the pipes will leech toxic amounts of lead into it. In order for Flint to repair its water problem, it has to replace all of the pipes in the city. This is really expensive and Flint doesn't have the money to do it. Most cities wouldn't have the money to do it, as they only budget for a certain percentage of pipes to be replaced and serviced every year. The replacement cost has been estimated to be $60M and the project, to be fully completed, to take 15 years. There are about 29,000 pipes that need to be completed. They are focusing on the most at-risk homes first and several hundred have been completed." ]
[ 757 ]
[ [], [], [], [], [], [], [], [ "https://youtu.be/IJbVK5UBRT8" ], [] ]
[ "url" ]
[ "url" ]
a0nbtw
Do different languages have different measures for determining eyesight?
For example, could someone have 20/20 vision when distinguishing between separate letters in English but less than 20/20 vision for distinguishing between the characters of Mandarin (assuming they are bilingual with equal ability to speak and understand each)? It seems like some languages have much more visually complex characters than others which would make them harder to identify than others when viewed from the same distance.
Culture
explainlikeimfive
[ "eaiznwa" ]
[ "So 20/20 just means what you see at 20ft is what \"typical\" people see at 20ft. If you see at 20ft what typical people see at 100ft, your vision is 20/100. This is almost exclusively as an American anectode to illustrate to lay people how their vision compares to others. Most other countries around the world use the diopter (measured by seeing how far your eye can focus) to determine degree of vision impairment. Glass prescriptions are in diopters (i.e. +1.00, -3.25, etc), where +0 is \"typical\"." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
5uz00n
Is there any benefit to having ice cream prepared on a marble slab?
Other
explainlikeimfive
[ "ddxycrk", "ddxx6r0", "ddy2roo", "ddy9gan", "ddyysic", "ddyn1mf", "ddydik2", "ddyq5dl", "ddxy1y3" ]
[ "The slab is refrigerated and kept very cold. This allows you to manipulate the ice cream and mix things into without it melting. Doing this in the store allows you to have very personalized icecreams rather than just having to have pre-mixed choices only. But you could do the same with a steel slab or anything else you could keep cold." ]
[ 224 ]
[ [], [], [], [], [], [ "http://i.imgur.com/ke9JvRr.gifv" ], [], [], [] ]
[ "url" ]
[ "url" ]
g9kd8v
Why do medics keep you awake when you’ve had a traumatic injury? Why would being unconscious be more dangerous?
Biology
explainlikeimfive
[ "fotwc5v", "foucoqf", "fou01hu", "fotw8od", "fotyedf", "foux82y", "fouwobg", "fov1mnp", "fovbrf6", "fouwl1l" ]
[ "Until the patient has time to get to a hospital and get good diagnosis, it is hard for anyone in the field to determine (other than gross external injuries) what actually is the most urgent issue. The patient is actually the best guide (location of pain, what happened etc) to assist them for immediate treatment. They will often want to know if the patient has any existing conditions, allergies or on medication as this informs them what they should avoid. In the case of head injuries and internal bleeding, in particular, there might be very little external signs. But if the patient cannot maintain consciousness or follow simple instructions, it might be indicative that there could be trauma and this needs more attention. Once a patient loses consciousness, a large part of this feedback mechanism is lost." ]
[ 461 ]
[ [], [], [], [], [], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
5vnos5
How do frogs just suddenly appear in areas that experience heavy rain where there wasn't any water before?
I'm from California, and we've obviously been in a drought lately. After the heavy rainstorms, I've been walking to a park near my house when the sun sets, and the croaking of what sounds like hundreds and hundreds of frogs can be heard all throughout the park. There are no bodies of water in the park, so how can the frogs just appear where there wasn't any water before?
Other
explainlikeimfive
[ "de3okku", "de3ocnp" ]
[ "On a mobile, so I apologize if this is choppy. This does happen in arid climates like the Southwest more than you might think. There are special native frogs and toads (like the New Mexico Spadefoot) that will sit underground for a long time, sometimes years*, until a heavy rain hits the area. They can stay underground for so long because they coat themselves in mucus and enter a torpor (very deep sleep) state. Once that perfect rain hits, they'll come up to mate and spawn. This whole process is very quick (on the order of a week or so!). They need to mate, spawn, and the tadpoles need to grow up quickly enough to be independent of standing water. After the mating-fest, the adults will dig back down several feet and wait again. EDIT: Decades might be a bit of an embellishment here...more likely just a few years." ]
[ 312 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6b1hnj
How is it possible that Greece, a rather small country with a population of around 11 million people, has managed to obtain a debt of around 350 billion Euros?
I found plenty of former ELI5s talking about the Greek debt, but no comments gave an in-depth explanation about this specific matter. What kind of expenses did Greece have in order to get into such a gigantic debt? How was all this money used?
Other
explainlikeimfive
[ "dhj2qga", "dhjf7tt" ]
[ "Greece is a mess. For one, they never should have been on the euro. It's well-known now that they fabricated financial information to join. This tied Greece to the European economy, and left other members of the Union afraid to let one of their own fail for fear of what it would mean to their own borrowing ability. Then there was the 2008 Global Financial Crisis. This hit Greece especially hard. The solution from the rest of Europe was a bailout. But the bailout backfired in some ways. For one, it was just more debt. That wasn't exactly what Greece needed. Second, the conditions that came with it, arguably, led to more unemployment, as Greece laid off many government workers. Third, it didn't force Greece to cut benefits for politically-powerful groups. Ultimately, it was just perpetuating the same failed debt policy. Now Greece is so mired in debt that the only practical solution is default or forgiveness. But nobody wants to (or can) pick up that tab. Nobody knows what to do." ]
[ 9 ]
[ [], [] ]
[ "url" ]
[ "url" ]
f7i24p
Why does yawning unplug our ears after catching cold but opening up our mouths like we are yawning intentionally doesn't unclog them ?
Biology
explainlikeimfive
[ "fic22h7" ]
[ "Because what happens in the back of your throat when you yawn is different from what happens when you simply open your mouth wide. You can reproduce the snick at the sides of your neck that unblocks the eustachian tubes without opening your mouth or touching your face. The sound is the same as if you block your nose and blow out, but you can have voluntary control over the muscle which does the same thing. > The tensor veli palatini tenses the soft palate and by doing so, assists the levator veli palatini in elevating the palate to occlude and prevent entry of food into the nasopharynx during swallowing. The tensed palate consequently provides a stable platform for elevation of the pharynx during swallowing by the pharyngeal muscles. Since it is also attached to the lateral cartilaginous lamina of the auditory tube (also known as the Eustachian tube), it assists in its opening during swallowing or yawning to allow air pressure to equalize between the tympanic cavity and the outside air. Equalization of air pressure in the tympanic cavity is essential for preventing damage to the tympanic membrane and a resulting loss of hearing acuity. And probably the levator veli palatini, too URL_0" ]
[ 4 ]
[ [ "https://en.m.wikipedia.org/wiki/Levator_veli_palatini#/media/File%3AGray907.png" ] ]
[ "url" ]
[ "url" ]
n6cyha
Why can animals eat the same food all their life and not get digusted by the taste, but humans can't?
For example, cows eat hay all the time, but when a human eats the same food repeatedly they get disgusted by the taste even tho they liked the taste initially.
Biology
explainlikeimfive
[ "gx6dhak", "gx6fwag", "gx6d7tx", "gx6bkoa", "gx6hf1x", "gx7bpra" ]
[ "Starve yourself for a day, see if you're still disgusted by the left-overs from two days ago that you didn't eat for one day. Hunger is a powerful thing, and animals don't have a guarantee that they'll be able to find 3 meals a day like some of us humans (there are places in the world where populations of humans starve, as you're probably aware). In any case, cows digest the [cellulose]( URL_0 ) of plants. Cellulose is made up of long strings of [sugar]( URL_2 ), and their stomachs actually break it down into these sugar molecules. Cows [ruminate]( URL_1 ), they use bacteria to ferment the hay and decompose it, they regurgitate it back to their mouths to chew on some more, etc... Think of it as \"cooking it\" in their stomachs, and re-tasting it as it changes from \"grass\" to \"fermented sugary slurpee\". And you never get tired of ice-cream (or other similar sweets), don't kid yourself. You would eat that day after day, if you could. So if the hay tastes like sweet ice-cream to the cows... they won't get tired of it." ]
[ 23 ]
[ [ "https://en.wikipedia.org/wiki/Cellulose", "https://en.wikipedia.org/wiki/Ruminant", "https://en.wikipedia.org/wiki/Glucose" ], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
7kpxov
How does fake wrestling work?
Culture
explainlikeimfive
[ "drg9dx1", "drg9z2q" ]
[ "Choreography. Wrestling is kind of like it’s own language. Randy Savage is famous for having most or all aspects of his match choreographed, while Ric Flair was respected for his ability to improvise. Headlocks and other close encounters are used to whisper moves/sequences on the fly, and many wrestlers these days perform most of the match without any previous discussion. Regular people fighting got boring, so for the past few decades storylines and other drama are added in to make the feud more dramatic. A lot of the business it based on honor, so a lot of the hits and falls you see really hurt, and championships are put on people the company who have the ability to combine athleticism and some sort of charisma. That’s why the Rock won a lot." ]
[ 7 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6wef3r
Is there any research showing that STEM toys actually have a positive impact on children's ability in real-life STEM?
Engineering
explainlikeimfive
[ "dm7rc5q", "dm7qju1" ]
[ "Lots of research has been done with STEM toys, but most of it asks the question of whether or not the toys help children learn STEM topics. Even less research is longitudinal (meaning the researchers observe subjects for a long time, usually years). One study that almost answers your question found that children who developed early interest in STEM topics had more access to opportunities to engage in STEM activities later in life. URL_0 B.S. Physics Teaching, M.S. (candidate) Instructional Psychology" ]
[ 10 ]
[ [ "http://onlinelibrary.wiley.com/doi/10.1002/sce.21018/full" ], [] ]
[ "url" ]
[ "url" ]
894bau
Why when you buy games on PSN or Steam you don't have to pay tax, but you do if you buy the physical disc?
At least in Canada that's the case. If you buy digital it's $79.99 on your credit card, however it's around $90 for the disc. Why is this?
Economics
explainlikeimfive
[ "dwowm5x" ]
[ "Technically under Canadian tax law your supposed to. When filling your tax return you are supposed to declare online purchases like then ones you described. I remember a from an article about 6 months ago where the government was looking to increase the recovery of these non-paid taxes. I’ll edit if I can find a link." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
9iknpt
How are ICBMs intercepted?
Technology
explainlikeimfive
[ "e6kccr3", "e6kg28n" ]
[ "Generally, they're not. There are anti-ICBM technologies but generally speaking they are not super reliable, especially when you consider the potential damage a single nuclear-tipped missile could cause. There's a few different methods. Generally speaking it's best to hit them in the boost stage, when they're moving the slowest. By the time they're re-entering they're moving a lot faster, and modern ICBMs oftentimes have countermeasures or multiple warheads/re-entry vehicles. 1. Blow it up with another missile using explosives - might still be able to disable it if you don't directly hit it and just blow up near it, but if the ICBM has radioactive or biological components, you might spread that all over. Far, far better than hitting its target though. 2. Blow it up or disable it with a kinetic kill vehicle - basically hit it with a missile that doesn't have any explosives and destroy it with sheer kinetic energy. As you might imagine, it's pretty difficult and kind of like hitting a bullet with another bullet 3. Destroy or disable it with a laser - Lasers have relatively short range, require a large amount of power, and take some time to do their work. Large read that covers different types of systems both actual and in test, that operate at various stages of a missile's flight: URL_0" ]
[ 27 ]
[ [ "https://en.wikipedia.org/wiki/Missile_defense" ], [] ]
[ "url" ]
[ "url" ]
iixffa
If SSRI'S block serotonin reuptake, how do anti-depressents differ? (ex. Lexapro, Zoloft, Wellbutrin?)
Chemistry
explainlikeimfive
[ "g3aaw3i" ]
[ "The actions of most psychoactive drugs, including pharmaceutical drugs like SSRIs, are not fully characterized. We don't know everything about how they work or all the effects they have. To the extent they are different, they can differ not only in their exact effect on the target receptors, but also in effects we don't know about or don't know much about. We actually don't know very much about the specific mechanisms behind depression and we certainly don't know much about the specific mechanisms by which various pharmaceuticals address depression. Monoamine (a type of neurological chemical that includes serotonin as well as other chemicals like norepinephrine) depletion is a hypothesis which has been widely distributed in the popular press as the explanation for depression, but it is not accurate, or at least not the full picture. It has been experimentally demonstrated that artificially reducing the level of serotonin in a healthy person's brain does not make them depressed, and it is a fact that SSRIs increase the level of serotonin in the brain within hours after administration, but it usually takes weeks for patients who respond to those drugs to notice any difference. Given that it is true that healthy people don't become depressed without serotonin and depressed people don't become healthy as soon as they reach normal levels of serotonin, serotonin depletion alone does not explain depression. The same is true for other neurotransmitters like norepinephrine. There are some antidepressant drugs which don't act on neurotransmitters at all, like opipramol and tianeptine. In short, the answer to your question is that we don't know enough about the brain or antidepressant drugs to provide a good explanation for why they differ in their efficacy." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
a59cyn
What happens when we stretch in the morning? Why does it feel so good and why is it almost compulsory sometimes?
Biology
explainlikeimfive
[ "ebkvvde" ]
[ "Our muscles and fascia are mostly unmoving while we sleep, and there is constant pressure from whatever we are sleeping on. This causes them to kind of bind together and get sticky, stretching pulls the layers apart and keeps our mobility and flexibility up. You may notice that people that sit for long stretches and don't keep up with mobility will become stuck, in a poor posture or with joint pain from parts pulling on unmoving parts." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
7iztik
Where does the air that causes an organ to produce sound come from and how is it carried to the pipes?
Engineering
explainlikeimfive
[ "dr2mzk3" ]
[ "In the Olden Days, it was provided by a set of [bellows]( URL_3 ), that some [assistant]( URL_0 ) had to keep pumped to keep the organ supplied with air. Nowadays on most organs, it's done with an electric air compressor, though there are still organs with bellows that exist. There's an organ in a church near me that still has bellows, though there's a compressor too. You can use either to get it to start working, though obviously you can't play and pump at the same time. *edit* Just noticed I only answered half your question. Hold on and I'll finish up. *edit2* for some reason I've just noticed somehow the system didn't save the second half of my message. There's a [air reservoir]( URL_2 ) inside the organ which is basically a box which has a weighted top that can move up and down on a sort of accordion kind of arrangement. As the bellows assistant pumps, or the compressor compresses, the top of the reservoir lifts up, and the idea is that while the top of that is floating (not topped out so it can't go any higher and not bottomed out), the organ will be provided with a steady flow of air. This is necessary otherwise the organ will only sound each time the person gives a pump, which obviously will make playing anything decent difficult. Beyond that there are valves controlled by the keyboards, which allow air to the appropriate pipes. To modify the sounds, there are [stops]( URL_1 ) which are basically selections to adjust which set of pipes the air goes to (or does not go to). Volume is controlled using pedals which open or close mechanical shutters to limit how much sound can come out of the pipes. That's about it in basic terms. Obviously you could literally write books on the mechanics of pipe organs." ]
[ 5 ]
[ [ "https://i.ytimg.com/vi/b03Pes5JAm8/hqdefault.jpg", "http://www.elycathedral.org/assets/pages/00000033/organ-stops.jpg", "http://www.dobsonorgan.com/html/instruments/op85_westhartford/reservoir3.jpg", "http://www.mexicanarchitecture.org/glossary/images/Oaxaca_Tlacochahuaya_SanJeronimo_full/33%20Wedge%20Bellows,%20Restored%20in%201991.jpg" ] ]
[ "url" ]
[ "url" ]
6z6n2d
How do we know multiple/parallel universes may exist?
Physics
explainlikeimfive
[ "dmsxt2a", "dmsyfmk", "dmsz7iz" ]
[ "We don't know that they exist, but if they did they would solve some problems in theories of physics. For example, physicists often ask why something came out the way that it did, but they generally don't like the answer, \"because our place in the universe is special\". So when they ask why is the charge of the electron the value we seem to measure or why the Planck length is the value it is, or why this particular quantum event turned out one way instead of another way that could possibly be, they want a more satisfactory answer. Parallel universes offer a way to answer these questions much more satisfactorally. The constants of our universe aren't special, there are many or infinite universes each with their own values and we just happen to be in this one with these values. The result of that quantum event actually happened both ways and we just ended up in the universe where it went the way we detected. We are no longer special and that makes phycists happy." ]
[ 13 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
dhjhsi
What exactly about sleep “recharges” the body and gives us energy?
Biology
explainlikeimfive
[ "f3og679", "f3ogovc" ]
[ "There's a chemical called Adenosine that builds up in your brain throughout the day. When it reaches a certain level, it makes you feel sleepy. When you sleep, your brain removes the built up adenosine. I highly recommend the book \"Why We Sleep\" by Matthew Walker. It is full of useful info like this and tons more." ]
[ 56 ]
[ [], [] ]
[ "url" ]
[ "url" ]
917f8f
Why are many freshwater lakes safe to swim in, whereas swimming pools have to be chlorinated?
Chemistry
explainlikeimfive
[ "e2vwaq7", "e2vx1sf", "e2w3m4m" ]
[ "Lakes are full of life, and the fish handle parasite and insect populations (by eating them) in a way that doesn't happen in swimming pools." ]
[ 69 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
6f13a8
Hi, so I've learned that Rodinia was a supercontinent. I thought Pangea was the name of it. Can someone?
Physics
explainlikeimfive
[ "diektcm", "diephf6" ]
[ "Rodinia was a supercontinent. Rodinia existed before complex life colonized dry land. It broke up before life moved to the land, and eventually the continents came together again to form Pangaea (for a short time becoming Pannotia, another supercontinent)." ]
[ 7 ]
[ [], [] ]
[ "url" ]
[ "url" ]
bd1caz
Why is only natural-born citizen able to run for president?
Other
explainlikeimfive
[ "ekv3lq2", "ekv22xo" ]
[ "It’s supposed to prevent foreign powers from infiltrating the government. Sort of an ironic thought in 2019." ]
[ 9 ]
[ [], [] ]
[ "url" ]
[ "url" ]
8pllj3
How Speakers Produce Audio
How does an object consisting of metal, magnet, wire, and paper/plastic produce audio? I’ve torn them apart before and they look super basic and I don’t understand how they produce audio.
Technology
explainlikeimfive
[ "e0c5rp4" ]
[ "Their operation is not really that complicated. First of all, sound is essential just a pressure wave in the air. Very similar to a wave in water. In water you can easily create such a wave by placing your hand in it and moving it back and forth. This is exactly what a speaker does. It's just a piston that makes the membrane move back and forth, causing pressure waves in the air. The mechanical movement is caused by a permanent magnet which gets pulled or pushed by an electromagnet. You can usually see those vibrations at low frequencies." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
a61mmk
How does barrel length on a gun improve or worsen accuracy?
Little confused on that
Physics
explainlikeimfive
[ "ebr05lo", "ebr0bok" ]
[ "A longer barrel generally improves accuracy as it increases the velocity and resulting spin speed of the projectile. Rifles are much more accurate than pistols for example, and rifles intended to be more accurate tend to have longer barrels. Extreme accuracy also benefits from a stiffer barrel which means a thicker, heavier barrel overall." ]
[ 10 ]
[ [], [] ]
[ "url" ]
[ "url" ]
65ej9i
How do people figure out what colors to use when coloring an old black and white photo?
Repost
explainlikeimfive
[ "dg9mnc3", "dg9p24u" ]
[ "\"Black\" and \"white\" are actually a ton of different shades of grey. If you know the method the picture was taken with and how it converts visible light into something that can be put onto film in greyscale, you can tell with a pretty high degree of accuracy which shade of grey corresponds to which visible light color." ]
[ 8 ]
[ [], [] ]
[ "url" ]
[ "url" ]
5mgk15
Why is it that teeth come in symmetrical pairs but aren't all the same shape?
Why is it that one tooth from the left side of the top row will have an exact same copy on the other side of the top row, but all teeth aren't similar in shape?
Biology
explainlikeimfive
[ "dc3gezc", "dc3fya6" ]
[ "Most things in our body are symmetic, on a cellular level this is because very early in embryogenesis a front and a posterior(\"back\") are defined and along this axis initiated by different concentrations of signal molecules, symmetrical expression patterns are developed." ]
[ 3 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6t0pyn
If plants grow berries to spread their seed via animals who eat them, why are some of them poisonous?
Biology
explainlikeimfive
[ "dlgyo8m", "dlgz9rv", "dlh7c11" ]
[ "'Berries' is pretty broad, and not all berries are necessarily 'to be eaten.' That being said, where poison berries are often dispersed by animals, it is because they are not poisonous to all animals. Instead, the poison may be 'selective,' discouraging browsing by animals who would destroy the seed or plant. As a non-lethal example, at least some plants with seed bearing bodies that we consider spicy are dispersed by birds, who don't destroy the seeds. The chemical responsible for us considering the pepper 'hot' has essentially no effect on birds, yet it can irritate mammals that might grind up the seeds or significantly damage the plant." ]
[ 48 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
67eid8
Why are American flags backwards on military uniforms?
Culture
explainlikeimfive
[ "dgptl0g", "dgptgri", "dgptnl2", "dgptgzd", "dgpyztp", "dgqdqqc" ]
[ "The flags are depicted as if they were being carried on a flag pole. Imagine each soldier is carrying a flag pole and walking forward at a fast speed. The flag will naturally unfurl behind them. Now if you walk alongside the soldier and look at the flag, it will match the patch on their shoulder. From one side you'll see the \"front\" of the flag with the blue section towards the left side of the flag. But if you were walking on the other side of the soldier you'd be seeing the \"back\" of the flag and the blue section would appear on the right side. Out of context, one shoulder patch looks correct and one looks backwards but in reality they are both correct when put in the context of a flag being carried into battle." ]
[ 107 ]
[ [], [], [], [], [], [] ]
[ "url" ]
[ "url" ]
evd5dh
How does cutting 1,500 jobs save a company 40mil in corporate taxes to the U.S.?
Economics
explainlikeimfive
[ "ffuz50l" ]
[ "It isn't tax savings - it is _pretax_ savings - impacts to the bottom line before taxation is calculated. It is common for companies to report EBIT (earnings before interest and taxes) or EBITDA (earnings before interest, taxes, depreciation, and amortization) because those are more comparable statistics between companies." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
kxlnte
How do surgeons not have their patients bleed during operation even though I bleed fountains from a paper cut?
Biology
explainlikeimfive
[ "gjb08fc", "gjb67q2" ]
[ "Cauterize the wound with electricity, basically burn it closed, and also use clamps on the blood vessels." ]
[ 17 ]
[ [], [] ]
[ "url" ]
[ "url" ]
6ugygy
what would happen to our bodies if we were to just take one pill every day that had all the nutrients and calories we need for a 'healthy diet'? Would we feel hungry?
Biology
explainlikeimfive
[ "dlsksxz" ]
[ "One of the main ways that the body recognises satiety (fullness), is by the activation of stretch receptors in the walls of the stomach. Our awareness of hunger/fullness and hydration/dehydration is largely down to physical factors such as having an empty stomach/gut and a dry mouth, for example." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
72efwx
What happens if senior US military leaders hold no confidence in orders from potus?
Culture
explainlikeimfive
[ "dnhuli9" ]
[ "They would either be arrested, or in the process of overthrowing the government. Military command's pretty rigid." ]
[ 14 ]
[ [] ]
[ "url" ]
[ "url" ]
aj57n4
what causes the ringing sound of tinnitus
Biology
explainlikeimfive
[ "eet0kbw", "eet2kol" ]
[ "This question made me think \"oh damn I wonder what\". & #x200B; I found this in the [webMD site]( URL_0 ): > The \\[constant exposure to loud\\] noise causes permanent damage to the sound-sensitive cells of the cochlea, a spiral-shaped organ in the inner ear. And also in [another page]( URL_2 ) of the same site > What causes the ringing? Usually it's from damage to tiny hairs in your inner ear. That changes the signals they send to your brain that control how you hear sound. & #x200B; Ok, so now, if still don't understand, you need to know a bit how ears work. If you don't know anything about inner ear anatomy, take a look [a diagram]( URL_3 ). The cochlea is that organ inside our ears that looks ike a snail shell. It is full of liquid and little hairs inside ([This image]( URL_1 ) illustrates it in a nice way). A sound is air vibrating: you are able to hear it because is vibrates your eardrum, and that vibration moves the tiny bones attached to it, who move in a way that will touch the opening of the cochlea. That makes pressure, and makes the liquid inside of it move, which in turn, moves the little hairs. These hairs are connected to neurouns that signal to the brain that there is a sond. Depending on the hair that moves, it says \"there is a sound of this frequency happening\". What seems to happen when you have tinnitus, is that some of these hairs where damaged, so they are constanly signaling the brain that there is a sound even when there's not, which translates into a ringing sound." ]
[ 5 ]
[ [ "https://www.webmd.com/a-to-z-guides/understanding-tinnitus-basics", "https://s3.medel.com/images/triformance/tonotopic-principal-of-the-cochlea.jpg", "https://www.webmd.com/a-to-z-guides/tinnitus-lifestyle#1", "https://www.earq.com/images/EarQ_Anatomy_of_the_Ear_Chart.jpg" ], [] ]
[ "url" ]
[ "url" ]
7tzklw
How do doctors/ nurses dispose of blood?
Biology
explainlikeimfive
[ "dtgfpjs", "dtgfiav" ]
[ "I worked for a company that disposed of medical waste among other things. Back at the plant they put it through a large mascerator or shredder like the ones you see on YouTube eating cars and sofas etc. From there it used to be incinerated, but the plant I worked at used high pressure steam ovens to melt/kill/destroy anything inside. And then it went off to landfill. They have since upgraded to a system where they burn waste in a low oxygen high temerature environment and use it as fuel for the plant itself, leaving only a fine ash as waste. Apparently the plant generates about 2 megawatts. The use something called pyrolysis and gasification. Edit [Shredder]( URL_0 ) [Steam oven]( URL_2 ) URL_1 Edit 2 Fyi you can enter \"medical waste disposal\" into YouTube and find several videos with methods like the one I described, even a few that use microwave to disinfect the material." ]
[ 14 ]
[ [ "https://youtu.be/SIqlKODeOLc", "http://www.globalsyngas.org/applications/gasification-vs.-pyrolysis/", "https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcQ__rTA3WcBKX_gNNwUONhT3_wsupseDZT9gk05zsXG1ITHw1HI" ], [ "http://www.interplas.com/product_images/biohazard-bags/Sealed-biohazard-bag-carried-nearest-medical-waste-pickup-container-300px.jpg" ] ]
[ "url" ]
[ "url" ]
5yvee6
Why does older furniture hold up so well when modern furniture seems to break in a few years?
Culture
explainlikeimfive
[ "deta9rb", "det9yvg", "det6o10", "detcj0c" ]
[ "The modern furniture you're seeing is cheap modern furniture. There's modern furniture that holds up well, but it costs a lot more. Why wasn't there cheap furniture years ago? There was. But you don't see it any more, because none of it survived to this day -- *because it was cheap*." ]
[ 17 ]
[ [], [], [], [] ]
[ "url" ]
[ "url" ]
d9kxnr
If the war on drugs has proven to be a failure, why are most governments focused on incarceration instead of rehabilitation?
Other
explainlikeimfive
[ "f1iirl6", "f1ij2jt", "f1ivhss" ]
[ "1. Not everyone is convinced the war on drugs has \"proven to be a failure.\" 2. Many people interpret \"tough on crime\" to mean \"tough on criminals.\" That the most appropriate way to deal with crime is to have harsh sentences. Creating criminals in a humane way by trying to \"fix\" them is seen as being weak on crime. 3. People profit from high incarceration rates and use that money to influence government officials to keep those policies in place." ]
[ 5 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
8wobjl
How Are Copper And Brass Doorknobs Able To Disinfect Themselves?
Chemistry
explainlikeimfive
[ "e1x78ok", "e1xhelq", "e1x5vmd", "e1xibmv" ]
[ "Copper like silver and other heavy metals shreds almost all life by strongly binding thiols and amines on various biologically necessary molecules. It's just heavy metal toxicity. It's amped up a bit because bacterial cells have negatively charged membranes that schlorps the metal towards it." ]
[ 285 ]
[ [], [], [], [] ]
[ "url" ]
[ "url" ]
a7ipmp
Why do some engines produce more torque or pure rpm than other even if it's smaller or less pistons.
Like a single cylinder engine can be stronger or higher cc's than a 2 cylinder engine (motorcycles)
Engineering
explainlikeimfive
[ "ec3bl9b" ]
[ "Smaller is *easier* to have a higher RPM red line on, because the reciprocating mass inside is much less, meaning the bearings aren't compensating for so much weight moving around in there. CCs (aka liters, also sometimes measured as cubic inches) is just how much air volume the engine as a whole can move. A humongous single-cylinder engine might have 10 liters of displacement, because that's how much of a difference there is in volume between the top and bottom of the piston stroke. Engine volume affects performance but isn't really an indicator of performance; for example my 256 c.i. engine produces nearly twice the horsepower, and more torque than, an old 318 c.i. Dodge V8, purely by having more advanced tech to harness the power put out by fuel combustion. A lot of factors go into torque, from bore and stroke to how much of the energy can be truly harnessed and turned into rotating motion through things like cylinder head shape and fuel injection and whatever else. Horsepower is just an equation factoring torque and the RPM that torque is being made at." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
j7uy9i
Why cell phones batteries capacity is represented in mAh, while electric car batteries capacity is in kWh?
When you look up specs of a cell phone battery, capacity is represented in Ah (Amp hours), while car battery packs are in Wh (Watt hours), with their magnitude prefixes respectively. I know their capacity differs greatly, but at a glance of an eye I don't have any idea how they compare. Why the different standard?
Technology
explainlikeimfive
[ "g874vux", "g8797vj" ]
[ "Amp hours have been the traditional measure of batteries for a long time because they represent the amount of charge stored in a fixed voltage battery. Typically you know the voltage of the battery so you can easily convert to the amount of energy stored. OTOH car batteries work at different voltages depending on the car. What you care about is the total amount of energy available, and this is what is being expressed by watt hours." ]
[ 12 ]
[ [], [] ]
[ "url" ]
[ "url" ]
9grm1v
Why do hairs begin to turn white the older you get?
Biology
explainlikeimfive
[ "e66dxhs" ]
[ "Your hair follicles are like printers that make their own ink. As you he older, the printers get worn out, and lose the ability to make more ink." ]
[ 56 ]
[ [] ]
[ "url" ]
[ "url" ]
eoyeyk
why do international relations develop so slowly and end so quickly?
Other
explainlikeimfive
[ "fefyvlk" ]
[ "Most relationships work that way in my experience. What do you think?" ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
mxf5lv
Why is foam white no matter the color of the soap?
Physics
explainlikeimfive
[ "gvnshbl", "gvp4hv2", "gvpfpev", "gvns6j5", "gvppo5o" ]
[ "Because colour comes from how light is reflected off surfaces. Any time there's a change in the medium the light is travelling through, such as the change between air and water, some of the light bounces off, some of the light changes angle of travel but keeps travelling in roughly the same direction, and some of the light is absorbed by the molecules of the new medium. Also, light has a property called wavelength, which is measured numerically. This wavelength property affects how the light is reflected, refracted and absorbed: For any given medium change, some wavelengths will bounce off, some will change direction, and some will be absorbed, and each of those wavelengths will do that to a certain degree. The \"colour\" of light is the result of our brains interpreting the wavelengths it is made up of. Light that contains lots of different wavelengths looks white, while light that only contains wavelengths of certain bands will look coloured. Lots of short wavelengths with no long wavelengths looks blue, lots of long wavelengths with no short ones looks red, and middle wavelengths with few short or long ones looks green. Intermediate combinations of wavelengths look the colours between these. For example, some long, some mid, no short will look yellow or orange. Also, purple is a trick of the brain, and it happens when the eyes detect both long and short wavelengths, but no middle wavelengths. So, let's imagine you have a bar of soap. This bar of soap is a kind of middle blue colour. It's not super dark, but it's not super pale either. It is very blue though, no purple or cyan tinges. This happens because when you shine a white light on the bar of soap, the middle and long wavelengths (the green and red ones) get absorbed by the soap, while the short wavelengths (the blue ones) get reflected. We see only the reflected wavelengths. About 50% of the short wavelengths are reflected to create that middle-strength blue. Hopefully that should make a bit of sense. Now, let's imagine you have a liquid soap, that's the same blue colour, but also transparent. This is doing much the same thing when it comes to light, but instead of being absorbed, some of the wavelengths pass through the soap, bounce off the sink surface beneath it, travel back up through the soap and then travel towards your eyes. You still get a blue tinge, because a lot of green and red light is still being absorbed by the soap, but enough is being let through that it also lets you see the stuff beneath the soap. Now, foam is kind of cool. Foam is actually a bunch of absolutely tiny bubbles, and a bubble is a thin layer of water with a hollow interior, and both the water layer and the air interior are transparent - they let some light through instead of absorbing or reflecting it. Light that passes through a bubble will hit a lot of surface changes. There's the surface change from the outside air into the water layer, then from the water layer into the inside air, then from the inside air into the water layer again, then from the water layer back into the outside air on the other side. That's four medium changes, and remember that each time light changes medium, a portion of it will bounce off. If say 10% of light bounces off each time light moves between air and water, then each time, only 90% of light passes through. After 4 transitions, a total of 35% of all the original light has bounced off a surface and back towards the light source. Get a bunch of bubbles, like foam is, and you've got hundreds of thousands of opportunities for light to bounce off. Almost no light is getting through, even though the air and water are transparent. The role soap plays in bubble formation is that it acts kind of like layers holding the water in a bubble shape. It works similarly to how oil behaves in water, forming its own balls of oil instead of mixing with the water. That happens because the oil molecules are something called hydrophobic - they don't like water and will try to hide from it inside a big ball of oil. Soap molecules are cool, in that one end of them hates air, and one end of them hates water, so when presented with both air and water, the soap molecules spontaneously organise themselves into something called a bilayer: Two rows of soap molecules that trap a layer of water between them, with their water-hating ends pointing out to hide from the water and their air-hating ends pointing in to hide from the air. [Here]( URL_0 ) is a kind of OK diagram of that. The molecules responsible for the blue colouration of the soap aren't involved in this process though, and water reflects light of all colours, so the special property of only reflecting blue light ends up lost when the soap molecules are mixed with water and air to make foam. Those blue colour molecules, which aren't the soap molecules but instead a dye molecule put in to make the soap look blue, are just tinging the foam a pale blue colour, as the water bubbles are doing loads of white reflection, but scattered blue dye molecules do still absorb some of the red and green." ]
[ 79 ]
[ [ "https://external-content.duckduckgo.com/iu/?u=http%3A%2F%2Fwww.nanooze.org%2Ffiles%2F2013%2F11%2FdroppedImage-22ss07y.jpg&f=1&nofb=1" ], [], [], [], [] ]
[ "url" ]
[ "url" ]
aamq9z
why does restarting seem to solve so many computer problems?
Heck, it solves many other problems with electronics too from a faulty bulb to a WiFi router.
Technology
explainlikeimfive
[ "ect7jz0", "ecu1cfj", "ectehyn" ]
[ "It clears the RAM and reloads all of the drivers. So if theres anything that is stuck or had a driver failure it fixed the immediate problem. The problem may still exist but its been put back to square 1." ]
[ 13 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
avnjsm
Why is brown sugar always "wet"?
Chemistry
explainlikeimfive
[ "ehghx6a", "ehghvzr" ]
[ "Brown sugar is just regular white sugar with molasses in it, molasses is just really refined cane sugar syrup, and when added together it makes the mixture damp, not necessarily “wet”. You want brown sugar to stay damp for different baking needs and that’s why they are always added in with the eggs and wet ingredients." ]
[ 34 ]
[ [], [] ]
[ "url" ]
[ "url" ]
laflwu
- Why exactly does a capacitor do what it does, and what even is capacitance anyway?
So I understand that the purpose of a capacitor is to store a charge, and I think it must also always discharge at a constant rate; otherwise you couldn't use them for "smoothing out" of power supplies. But the concept of capacitance is rather odd to me. What is the farad? Why don't we measure capacitors in how much charge they can store - i.e. in coulombs - or in how much energy they can provide - i.e. in joules or watt-hours? And how does having a pair of conductors with an insulator in between - which, as I understand, is the basic construction of a capacitor - create this affect?
Physics
explainlikeimfive
[ "glo55tp" ]
[ "What helped me really *understand* the concept of capacitors at an ELI5 level, when I was starting out, was *water analogies*. In a water circuit, water equals charge, pressure equals voltage, and flow equals current. In this analogy, a capacitor is like [an elastic membrane]( URL_0 ). If you increase the pressure on one side (apply a voltage), it will bow in the opposite direction - letting some water (charge) store itself on the capacitor. If you remove the pressure (turn off the pump), the elastic force of the membrane will apply a restoring force (voltage) moving the water back to its original, even, distribution. > But the concept of capacitance is rather odd to me. What is the farad? Why don't we measure capacitors in how much charge they can store - i.e. in coulombs - or in how much energy they can provide - i.e. in joules or watt-hours? Now, crucially, the amount of water that the membrane actually allows you to move depends on the *pressure* you're applying. Even though the physical dimensions and properties of the membrane are obviously unchanged, applying only a little pressure makes it bow only a little (thereby storing only a little charge). This is true for real capacitors as well - the more voltage you apply, the more current you can store on the capacitor. This is why we use Farad instead of measuring the charge directly. `1 F` is equal to `1 C` at `1 V`. But at `100 V`, that `1 F` capacitor would instead store `100 C`. This is also the reason why it doesn't make sense to directly rate a capacitor in terms of its \"stored energy\" - the more voltage you apply, the more charge you get, so the energy stored in the capacitor also goes up (twice, resulting in quadratic scaling!). > So I understand that the purpose of a capacitor is to store a charge, and I think it must also always discharge at a constant rate; otherwise you couldn't use them for \"smoothing out\" of power supplies. There is a possible error in your assumptions here. In a DC system, a capacitor does not actually gain nor lose any charge - it acts like an insulator. The reason they're used to \"smooth out\" power supplies is because, like a big \"tank\" of charge, they smooth out sudden *changes* in the supply voltage. Going back to the water analogy, imagine a sudden shockwave in the water front - when it hits the elastic membrane, it would get directly transferred through this low resistance membrane to the other (low pressure) side, rather than through the high resistance main system that you're trying to protect from such shockwaves. The reason this works might be above ELI5 level but the tl;dr of it is that capacitors have a variable resistance depending on the frequency - so sudden changes in voltage (lots of high frequency components) result in relatively low resistance through the capacitor, whereas for low frequencies (especially DC, which has a frequency of 0), a capacitor acts like an insulator." ]
[ 9 ]
[ [ "https://ece.uwaterloo.ca/~dwharder/Analogy/Capacitors/images/membrane.02.png" ] ]
[ "url" ]
[ "url" ]
5yg2qz
How exactly are files transfered via Wi-Fi and what dictates the transferspeed.
Is it just sending information what Data the destination Drive needs to write? If so, is the bottleneck how fast the source can give out the information or is it the writing speed of the destination? Or does it work totally different?
Technology
explainlikeimfive
[ "deppwm8" ]
[ "Yes. Essentially, the data transferred is just a stream of 1s and 0s for the destination drive to write (it's probably encrypted, and it has some extra stuff around it to make sure that the data reaches the destination computer intact). The bottleneck depends on a) the destination drive's write speed and b) the WiFi speed. The WiFi speed is not always as simple as it sounds, because it can be affected by interference. Normally WiFi networks operate somewhere between 20 and 50 Mbps, which is slower than hard disk drives (even HDDs should be capable of writing at around 80MBps - note that capital B there which means it's 8 times faster than a small b) unless they're damaged or worn out. VERY new WiFi networks (called ac) can transfer at up to 20MBps for short periods of time, which is still 4 times slower than an old-style HDD can write the data. The difference is even more apparent with SSDs, which can write data many times faster than even the most modern WiFi network can transfer it." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
b3ks1t
How is it possible to experience physical symptoms from having your heart broken?
Biology
explainlikeimfive
[ "ej0b5z8" ]
[ "[takotsubo heart syndrome ]( URL_0 ) . This should answer your question. The answer is yes it literally tugs on heart strings and can make valves fail. You can die if it’s bad enough" ]
[ 4 ]
[ [ "https://www.health.harvard.edu/heart-health/takotsubo-cardiomyopathy-broken-heart-syndrome" ] ]
[ "url" ]
[ "url" ]
ggxfd8
Why is it warm on earth but freezing cold in between?
Other
explainlikeimfive
[ "fq5dcfn" ]
[ "The vacuum of space is actually quite hot, but not dense enough for you to feel that heat. Just as hot air doesn't feel as hot as hot metal, the hot gas in space is so incredibly thin that you wouldn't notice that heat. As such, the dominant factor in determining how hot an object left in space gets becomes radiation. Radiation, including light from nearby stars (of the sun if you're in the solar system), heats objects. Meanwhile, objects cool by radiating heat. The more of an object is in the sun and the blacker that part of it is the hotter it gets. The more is in the shade and the blacker it is, the colder it gets." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
6cr7os
Why are Saturn's rings (and other planets) located at the center of the planet rather than closer to the top or bottom?
Physics
explainlikeimfive
[ "dhwsegi", "dhwrsu6" ]
[ "Objects orbit it must orbit the center of a body. It might be tilted, so that is above the equator in part of it's journey and below for an equal part. It can't, all be above the equator, for example, because then it wouldn't be orbiting saturn's center. As far as why not just a random cloud - Spinning clouds of stuff in 0 gravity resolve (and everything seems to be spinning) collapse into disks due to gravity. Dust clouds, solar systems, even whole galaxies The objects that compose the rings are thought to be the remains of moons that strayed too close to saturn and was ripped apart by it's gravity (the closer parts being enough heavier than the top due to the gravitational gradient to rip it apart). So it all has to be going basically in the orbit the moon was in. Almost all moons rotate on the same plane that the planets do. because they were part of the same original cloud. ( I think Titan is an exception, and it has been speculated that it may be captured rogue planet. ) Edit - the moon is Triton - thanks guys." ]
[ 4 ]
[ [], [] ]
[ "url" ]
[ "url" ]
8rv7oq
Why does the camera add ten pounds?
Other
explainlikeimfive
[ "e0uhfh2" ]
[ "Funnily enough I just read about this! Wider focal lengths make an object appear to wider/bigger. Nowadays, cameras actually 'take away' pounds, because they use thinner focal lengths. Watch this for a pretty cool example of how pictures change due to focal width: [ URL_0 ]( URL_1 )" ]
[ 7 ]
[ [ "https://78.media.tumblr.com/2a6c11cd7fa3178f45ed6497070b94bc/tumblr\\_inline\\_p9df90eunf1qajta6\\_500.gif", "https://78.media.tumblr.com/2a6c11cd7fa3178f45ed6497070b94bc/tumblr_inline_p9df90eunf1qajta6_500.gif" ] ]
[ "url" ]
[ "url" ]
6tn2s1
So I remember in the movie Zodiac someone mentions that handwriting is like a finger print and that even if you try to change it there's always a giveaway. Is this true?
I've noticed that some of my letters change drastically with something as unintentional as hand placement. However, since the movie's based on true events I'm not sure if this part was just made up to complicate the plot or not (Haven't read up too much on the real case). Maybe I just don't pick up on the nuances of my handwriting.
Other
explainlikeimfive
[ "dllyupc" ]
[ "At the time the film takes place, it was believed that this was true, however, this type of handwriting analysis is considered pseudoscience today. It's called [Graphology]( URL_0 ) if you want to know more." ]
[ 3 ]
[ [ "https://en.wikipedia.org/wiki/Graphology" ] ]
[ "url" ]
[ "url" ]
9q2wrd
If mobile processors are now (in some cases) overtaking laptop and desktop processors in terms of power why aren't they universally adopted into all laptops and you could make the battery last 10 times longer?
Technology
explainlikeimfive
[ "e867hge", "e867qkz", "e8675g1" ]
[ "Your premise is wrong, mobile processors don't outperform desktop processors. Not by a long shot." ]
[ 36 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
fc5pdt
How does a touch screen detect touches under glass?
It's like magic, how do it work??
Technology
explainlikeimfive
[ "fj8plll" ]
[ "It measures capacitance. Your finger is conductive. The \"glass\" is non-conductive. There is a layer of transparent conductor under the glass. Wherever your finger touches, a capacitor forms -- an area capable of holding an electric charge. By reading the capacitance of each area of the screen, it can determine where it is being touched. This is why non-conductive object such as styluses do not register as touches." ]
[ 9 ]
[ [] ]
[ "url" ]
[ "url" ]
lvj4gf
why does a "dead" tooth hurt?
Biology
explainlikeimfive
[ "gpc4euj", "gpc7imk" ]
[ "Usually because of a massive bacterial infection, which may be spreading through the gum or into the jaw. Just like an infected wound on your skin hurts a lot, an infection in your mouth also hurts a lot. As always: Do not take medical advice from the internet. Do not take medical advice from Reddit. If you're experiencing tooth pain, speak to your doctor or dentist." ]
[ 22 ]
[ [], [] ]
[ "url" ]
[ "url" ]
kju2gi
What emits light at the centre of galaxies?
If I understand correctly, black holes are the centres of galaxies, so what emits light in the centre of galaxies that we see from far away?
Physics
explainlikeimfive
[ "ggyunfm", "ggzb1ox", "ggyy68t" ]
[ "Stars are packed much more densely near the centers of the galaxies, because they are attracted by those black holes. So it’s all those stars all around those black holes that emit the light that we see at the center." ]
[ 23 ]
[ [], [], [ "https://www.nasa.gov/image-feature/goddard/hubble-peers-into-the-most-crowded-place-in-the-milky-way/" ] ]
[ "url" ]
[ "url" ]
62fs4z
why does the death penalty take so long to administer?
What can a serial killer who has eye witnesses and dna evidence have that allows them to appeal for 15 years?
Other
explainlikeimfive
[ "dfm6hqf", "dfm6ll3", "dfm6o8q" ]
[ "> What can a serial killer who has eye witnesses and dna evidence have that allows them to appeal for 15 years? Nothing to lose. In normal cases, your ability and desire to appeal is based upon the cost (time and money) weighed against the likelihood you will succeed. You're not going to spend 5 years for an unlikely appeal against a 6 month sentence. When you are *going to die*, **forever** that calculation is kind of skewed. Also, the justice system grants extra scrutiny for capital punishment cases because it's something we really, really, really don't want to be wrong about it." ]
[ 10 ]
[ [], [ "https://en.wikipedia.org/wiki/Overturned_convictions_in_the_United_States" ], [] ]
[ "url" ]
[ "url" ]
630hs7
When jumpstarting your car, why do you connect the black cable to the engine block instead of the black/negative terminal?
My mother needed a jump start earlier today and insisted on connecting red to red and black to black. Looking at the instructions on the cables and, later, on the internet you're supposed to connect the black cable to an unpainted section of the engine block of person's car with the dead battery. My mother insisted on doing it her way because she's done it that way before and it worked. I wasn't going to win the argument so I went along with her. Fortunately, the were no electrocutions or explosions. this time. So why do the instructions on the jumper cables say to do it their way and what could happen if you continue doing it incorrectly? Thank you in advance.
Engineering
explainlikeimfive
[ "dfqcv2u" ]
[ "Sparks near the battery can cause hydrogen fires. Sparks near the engine block are much safer. That said, modern batteries are sealed and pretty safe, but safer is always better." ]
[ 12 ]
[ [] ]
[ "url" ]
[ "url" ]
ebg17m
What causes the sensation you feel when you stretch?
Biology
explainlikeimfive
[ "fb4kmpp" ]
[ "Basically, your stretching your muscles is actually a form of mild pain, and it causes a message to be sent to your brain, telling it \"hey, give me some of that good stuff, this hurts.\" That causes your brain to release one of your feel-good chemicals, called endorphins." ]
[ 6 ]
[ [] ]
[ "url" ]
[ "url" ]
fscnb2
how can I go to bed hungry but wake up and not be hungry?
Biology
explainlikeimfive
[ "fm0l2sl" ]
[ "You have a functional liver. One of the functions the liver fulfils is converting stored fat to ketone bodies that your central nervous system can use for fuel as an alternative to glucose (blood sugar). Since the abundance of viable fuel for your brain is a large factor in deciding whether you feel hungry, sleeping for 8 hours can make the sensation of hunger go away." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
cteoxi
Do animals recognize when humans help them?
I often see feel good videos of people removing straws from turtle noses, pulling a horse out of a Texas gate, saving a duck out of an oil spill, etc... A lot of times the animals just run off (I understand they are probably shook) but sometimes it looks like the animal stops and says “hey thanks human” (lookup human helping sloth cross road) is this a coincidence? Do animals recognize when they have been saved?
Psychology
explainlikeimfive
[ "exkb1pg", "exkhqpo", "exlu03y", "exsxu9g" ]
[ "Since we do not know the personalities of animals, I can only assume - No. Cats ie. - if they are shy/stray and stuck at a rooftop, they may realise that humans provide an escape-route, but as soon they get hold on safe ground, they dash away in terror. Domestic cats rather may show some gratitude - but they do so as well when you pet them." ]
[ 17 ]
[ [], [ "https://www.telegraph.co.uk/news/2016/06/02/wounded-elephant-appears-to-plead-for-help-from-humans-after-bei/" ], [], [] ]
[ "url" ]
[ "url" ]
67f3v8
What is the Chechnya problem? How did it get so out of hand? Is Chechnya a part of Russia or not? Is it true that most ISIS leaders are from Chechnya?
Other
explainlikeimfive
[ "dgpyrp1" ]
[ "Chechnya is a region of Russia in the Caucasus area. They were conquered by the Russian Empire centuries ago, but have never exactly been happy about it. Chechens are mostly Muslim, and the Russian Empire was strictly Orthodox Christian. Later the Soviet Union was officially atheist and repressed most outward displays of religiosity. This has been a major point of anger for Chechens for centuries, being a mostly Muslim people ruled by a Christian empire and later a state atheist regime. Chechens have fought numerous rebellions attempting to be free from Russian rule. When the Empire fell in 1917, they fought for independence but were re-conquered by the new Soviet regime. Later in WW2, they mounted and insurgency starting in 1940, and collaborated with the Nazi invasion, hoping to win their independence from the Soviet Union. This failed again and the Soviets re-took full control of their territory. In retaliation, Stalin rounded up literally hundreds of thousands of Chechens and re-settled them thousands of miles away. Many thousands of civilians died as a result. Then again in the 1990s, when the Soviet Union fell and the new Russian Republic was born, the Chechens fought again for independence, in a bloody civil war in which Putin rose to prominence because he led the government's effort to crush the rebellion. This latest rebellion in the 1990s took on an Islamist flavor. Extremist fundamentalist Islam has been gaining in popularity all over the world since the 1970s. Many nationalist and separatist movements in non-Muslim-majority countries have adopted Islamist ideology and the tactic of mass terrorism against civilians. Several deadly terrorist attacks in Russia have been committed by Chechen separatist-Islamists. Many Chechen Muslims have adopted more strict and fundamentalist displays of Muslim piety in recent decades, like men growing beards, abstaining from alcohol, praying five times a day, and women wearing the burka. At present, the rebellion is mostly under control. Putin has a puppet governor ruling in Chechnya which is ruled \"semi-autonomously\" from the central Russian government. This means technically Chechnya has some rights to make its own laws, but for the most part, the lower government in Chechnya follows orders from the central government in Moscow. So basically to answer your question, *yes*, Chechnya is a part of Russia. But many Chechens would prefer not to be part of Russia. The puppet governor is a harsh-handed Islamist thug, but as long as he doesn't demand Chechen independence, Putin (himself a thug) tolerates and supports him. As for ISIS, *many* ISIS fighters and leaders are indeed Chechens. But it would be incorrect to say most ISIS leaders are from Chechnya. The majority are Arabs, and most of the leaders and fighters in ISIS are locals, from Iraq and Syria. But a very significant source of their foreign fighters is Chechnya, yes." ]
[ 8 ]
[ [] ]
[ "url" ]
[ "url" ]
bryegg
Why do phones and tablets power on and off with full 100 % brightness regardless of the scree brightness settings?
Technology
explainlikeimfive
[ "eohkit9" ]
[ "There needs to be a program running to control the screen brightness for it to be set to some amount. In those situations, there is no process running for that, as it requires an operating system to run, which isn't running completely at that time. There are ways around it but its not really a necessity for the few seconds it takes for the phone to turn on or off." ]
[ 5 ]
[ [] ]
[ "url" ]
[ "url" ]
8sb05u
Why aren’t tornados clear?
Other
explainlikeimfive
[ "e0xx925" ]
[ "It picks up dirt and debris from the ground, and it has water in it from the storm as well as from the ground. It is far more than just spinning wind." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
m3mdt1
How does a fridge work?
Engineering
explainlikeimfive
[ "gqpm7xu", "gqponw0" ]
[ "If you have gas in a closed container and try to compress it (squeeze the container), the gas will also get hotter because the molecules of gas get closer together and rub one another more vigorously, generating heat. So you used energy to generate heat. If, on the other hand, you expand the container, the gas will actually get colder. So you just used energy to \"generate cold\". Such a machine is in the refrigerator expanding the gas, \"generating cold\", absorbing the heat from inside of the fridge, and taking it outside to cool to room temperature. Basically you transport heat energy from inside to the outside by cooling the gas in one place, letting the gas warm up a little bit and absorb the heat of the inside, and let it out somewhere else. And repeat." ]
[ 13 ]
[ [], [] ]
[ "url" ]
[ "url" ]
a1kp0u
How can birds sit on power lines without getting electrocuted?
Physics
explainlikeimfive
[ "eaqkluv" ]
[ "Its not voltage that kills, its current. If you never provide a more enticing path for the voltage to flow to ground than its current (heh) path through the wire, it won't want to flow through you. This is why if a live hydro wire falls on your car, don't get out! If you touch any of the metal of your car and the ground the electricity will flow through you and you fry (literally). While you're in the car you're at the same potential as the wire, but there's no current flowing because the tires are insulators. So as for the birds are concerned, just sitting on the wire doesn't do anything so long as they don't ALSO touch anything that is grounded. If they were to hop on to one of those ceramic insulators and touch the live wire AND the metal tower at the same time - zap!" ]
[ 5 ]
[ [] ]
[ "url" ]
[ "url" ]
6pxb2w
What do people mean when they blame the "older generation" for ruining housing and the economy?
I see this on Reddit a lot. Goes something along the lines of old people not having any right to complain about millenials doing X or not buying Y because old people ruined the housing market and the economy. Everyone just seems to agree with those comments, but there's never any further explanation. Googling it just turns up a shitload of information about population density, trade, automation all mixed in long sentences with big words which become incomprehensible after a paragraph or two. Send help
Economics
explainlikeimfive
[ "dkswd69", "dkt8aew", "dksydqc" ]
[ "In general, the baby boomer generation went to college, got married, bought houses and retired from companies they had worked for for many years. Millennials, on the other hand, generally haven't got the earning power to do that. They often graduate college in debt or skip college entirely, generally don't have long-term relationships or have several non-traditional relationships, can't afford to buy houses and change jobs when opportunity arises or circumstance dictates. This is because the cost of college has skyrocketed, the cost of housing has skyrocketed, no one can afford to tie themselves financially to another person because divorce is expensive, and companies no longer provide the cradle-to-grave benefits that they once did since it makes more financial sense to offshore production to somewhere where companies don't have to pay for pensions, safe working environments or living wages in America. Since boomers are generally making the decisions at large corporations, speculating in the housing market, lobbying for insurance companies and by and large were in charge during the time millennials came of age, many millennials blame them for screwing over their generation. Boomers usually respond with \"work harder, like we had to do\" and ignore the fact that prices and values for *everything* were much, much lower when they were the age of the millennials." ]
[ 32 ]
[ [], [], [] ]
[ "url" ]
[ "url" ]
a7juey
What was the emancipation of dissonance?
I hear this term thrown around a lot, and never had someone explained it to me in a way that isn’t full of musical lexicon I can’t easily wade through. Any help?
Other
explainlikeimfive
[ "ec3juu0" ]
[ "Maybe not for an actual five year old, but think about beer. Most beers people start drinking are Bud, Coors, Miller, common beers that really don’t have a lot of flavor to them. They’re relatively easy to drink. And then as you get used to those, you move onto more and more complex beers, maybe Guinness, and then you end up in super heavy IPAs and trappists that have a ton of complex flavor, but if you had those first you would probably think them too sour or bitter and wouldn’t enjoy them. Pretty much the exact same thing happened with music. Early music started with the church, and they really weren’t allowed to use notes that sounded “bad”, because they were dissonant. Well, as time went on, more and more notes were added and we became accustomed to them, to the point were almost all notes in the right context can sound “good”, making them useful musical notes I hope this answers your question, it’s kind of hard to avoid actual music terminology when you get into why some notes are consonant/good or dissonant/bad" ]
[ 25 ]
[ [] ]
[ "url" ]
[ "url" ]
6blf65
In Star Trek, if the universal translator translates alien languages, how can Klingons still speak Klingon in front of Humans and not have it sound English?
Culture
explainlikeimfive
[ "dhnkaxr" ]
[ "Dramatic effect, really. You need the universal translator for the plots to make sense without your audience having to learn Klingon, but you don't want to ditch the cool 'alien culture' aspects. Bam, you're boned, you just have to fudge it." ]
[ 3 ]
[ [] ]
[ "url" ]
[ "url" ]
du2lqj
why does an increase in entropy decrease the total energy able to do work in a system?
So I understand that entropy is a "measure of disorder", and that low entropy means an unlikely state and high entropy means a likely state, but what does all this have to do with thermodynamics and the heat death of the universe?
Physics
explainlikeimfive
[ "f71bqqn" ]
[ "All matter wants to be in the lowest possible energy state it can be. This is achieved by giving off energy to its less energetic surroundings until an equilibrium is reached. This is called an increase in entropy. For example: a pot of boiling water left in a room will cool down until it has the same energy (as in temperature) as everything around it. This is the maximum entropy for this system (the room with the pot). Now anywhere where work is done energy is released from a high energy source until some equilibrium is reached. For example: a hydroelectric power plant produces energy by letting water flow from high up (high potential energy) down past a turbine until no more water is high up (an equilibrium is reached). The same principles apply to everything from car engines to batteries. The heat death of the universe is a theory that speculates that at some point entropy will reach its maximum and so no more work can be done. This means generating heat and moving stuff as well as everything else that requires energy (chemical processes for example). Literally, nothing will happen anymore. Edit: I thought about an analogy: Imagine you had a tub of sand. The individual grains represent atoms and the tub they are in is our universe. Now you bury a bunch of firecrackers and light them. They are going to pop and release heat/energy and make the grains bounce around. But at some point, all the bouncing grains will have come to rest and there will be no more energy input. So the individual grains are still there, there is just nothing happening anymore." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
5t1u2n
effects cannabis can have on developing(teenage) brain?
I have read lots of different opinions on this, since I know a handful of people who smoke regularly. I've heard peoples opinions, but I want unbiased information.
Biology
explainlikeimfive
[ "ddjhzvi" ]
[ "At the moment there isn't any concrete information. Being as marijuana is still a Schedule 1 drug the process for acquiring the correct permits to do studies on it is nearly impossible and will remain that way until the DEA decides to reschedule the drug. A side effect of it being so hard to actually study the effects marijuana has is that we know very little about the long term effects use can have on developing minds, or any minds for that matter. In fact if you were to go looking for research about marijuana you'll probably find about 50 contradicting studies, once a week you'll get a legitimate study saying \"The dangers of marijuana abuse\" and another legitimate study saying \"Marijuana found to have no adverse effect on congition\". So until the DEA stops it's ignorant game of monopoly we won't see any concrete information. The few things we do know is this: Marijuana IS addictive. Addiction can cause serious dependancy over long term use. Withdrawals can include insomnia, depression, anorexia, and mood swings. Marijuana is detrimental to short term memory. Unfortunately the extent of this is unknown. Marijuana can cause panic attacks. How or why, there is no concrete information. I have to add that combustion is obviously not good for your lungs, but there is a vaporizer and edible only movement with the cannabis community too. Hope that helps." ]
[ 7 ]
[ [] ]
[ "url" ]
[ "url" ]
bx1v2o
Why are snails able to move over razor blades without being cut or sliced?
What occurs that prevents a snail from being injured when moving over a razor or sharp object?
Biology
explainlikeimfive
[ "eq2h188" ]
[ "Because snails don't really touch the surface that they are traveling along. They secrete thick mucus, and then Glide along that mucus. The mucus is thick enough that it covers the Razer Blade and protects the snail. It is somewhat similar to a human throwing a blanket over razor wire before crawling over it. The blanket is enough to cover the razor wire and make it no longer an issue." ]
[ 4 ]
[ [] ]
[ "url" ]
[ "url" ]
979r44
Why are handshakes used in meet and greets or why are they a sign of friendship?
Culture
explainlikeimfive
[ "e46i3tk" ]
[ "I believe they were originally used as a way to establish trust where both parties prove to each other that they are not concealing anything (like weapons) in their hands" ]
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cpuimy
If x amount of money were introduced (discretly, with no one noticing) to the market, how does the market "know" that that amount of money has been introduced (thus adjusting prices)?
Economics
explainlikeimfive
[ "ewro9gm", "ewrnvmo", "ewrpor5" ]
[ "It only \"knows\" when the money is spent. Imagine a really simple economy - Alice, Bob and Chuck. Alice bakes two loaves of bread every day, and Bob and Chuck both earn $1 per day, which they each use to buy a loaf of bread. Now, one day (as if by magic) Bob and Chuck both get $2 per day instead of one. Bob gets to Alice first, and buys both loaves of bread for $1 a piece, spending his full $2. Now Chuck is upset because he has money, but no bread. Supply and demand are out of sync - at the price of $1 per loaf, there is more demand than there is supply. Alice has two choices: - Bake 4 loaves instead of 2, and keep charging $1 to extract all $4 from the economy - Charge $2 per loaf instead of $1, extracting all $4 from the economy Alice, being a smart baker, decides just to raise prices." ]
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8znesg
Most over the counter pills (e.g. ibuprofen) have a recommended dose of at least 2 pills. If this is the case why don’t the medicine companies start producing pills with twice the dosage?
Biology
explainlikeimfive
[ "e2k05ad", "e2jz5o1", "e2jz63p", "e2k7bjv", "e2jztp0", "e2kbh2e" ]
[ "There's a few good reasons: 1. If you only want a half dose, it's easier to take one pill than to cut a pill in half 2. If you want a stronger dose, you can take 3 or 4 (check the drug label first!) and vary the dosage more easily 3. A stronger pill would be larger and harder to swallow. Many people would rather take 2 small pills than one giant pill." ]
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84ce79
Why does squinting work?
To an extent.
Biology
explainlikeimfive
[ "dvoizsp", "dvp5sgs" ]
[ "When you squint you cut off the top and bottom edges of your pupil, making your pupil closer to a pin hole camera. The smaller the hole, the sharper the image, regardless of the shape of the eye or the shape of the lens. The trade off though, is that the image is dimmer." ]
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99g780
Stars vs Gas Planets
So, stars are largely made up of gasses, I know that and I know the basic definition of planets. But we have gas planets as well. I was wondering what is the distinction between gas planets and stars. It has some to do with the cores, right?
Physics
explainlikeimfive
[ "e4ndkah", "e4ndo8y", "e4ng6zs" ]
[ "A star has enough gravity to squeeze it's gases together so much that they start to undergo nuclear fusion, thus causing a star to radiate energy. A gas giant doesn't. In between is gas giant and a star is a brown dwarf, which is not massive enough to sustain nuclear fusion of ordinary hydrogen to helium in their cores, but can fuse deuterium and lithium if their mass is large enough. They radiate a small amount of energy." ]
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g3gzol
Why do they construct manholes in the middle of the roads?
Engineering
explainlikeimfive
[ "fnr8wzy", "fnrad9q" ]
[ "Manholes usually cover deep trenches used for sewage or storm systems. They work best in the middle of the road because they can service both sides of the road while leaving the areas on the shoulder/sidewalk free for shallow systems like electricity or gas that are typically used for buildings near the sidewalk anyway." ]
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5pwpox
Why do flight attendants request that airplane windows be open for landing? What effect does it have on anything?
Engineering
explainlikeimfive
[ "dcue0j8", "dcue3xv", "dcuf38n" ]
[ "There are several potential reasons: * It provides a way for emergency responders to see into the plane in the event of a crash. * It provides additional light (useful if there is heavy smoke) for the flight attendants to more easily ensure no one is left in a row during an evacuation. * It provides occupants of the plane a way to see outside and have more information to judge the conditions outside an exit door which may not have a large window." ]
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