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cffy98 | What is the “God Particle”, and how does it work? | The "God Particle" is a sensationalized name attached to a particle called the "Higgs boson," named for the physicist who first theorized its existence.
The Higgs boson is a consequence of something called the Higgs *field,* and the Higgs field solves a problem that particle physics had been grappling with for decades: some of the physical theories we've devised failed to work in certain circumstances. Namely, ***how did anything in the universe come to have mass at all?***
By assuming the existence of a field with certain properties, physicists were able to solve that problem and make physics "work" again.
Physicists then set out to discover whether that field actually existed, and to do that they needed to detect the particle associated with that field. That field and particle is the Higgs field and Higgs boson. | 7f1b2cfa-0e86-4422-8813-6c419a14e036 |
cffyeh | Where and how do mountains, rivers, forests, and deserts form? | Generally speaking mountains form in one of two ways.
The primary way is due to plate tectonics. The surface of the Earth, the continents and sea floor are broken up into a series of plates which sit on top of the mantle which is made up of liquid molten rock. As a result the plates are in constant but very slow motion. When the plates suddenly jerk and move we get an earthquake.
Where the thicker and tougher continental plates meet the thinner and weaker oceanic crust, the plates heave over each other. The Oceanic plates subduct (go underneath) the continental plates which causes the continental plates to be forced up creating mountains.
The second way to make a mountain is through volcanism. Hot molten rock finds a way to punch through the crust of the earth spewing onto the surface creating a volcano. Over time this volcano erupts numerous times, causing molten rock to pile up to form a volcanic mountain. These are most prominent in the ocean because the oceanic crust is thinner and weaker.
Mountains and the continents themselves are what cause forest, deserts, and rivers to form.
Ice forms at high altitudes from rain falling on mountains. This melts creating the sources of rivers. Rivers will then flow downhill and across the ground until they reach an open body of water like the ocean. Rivers are also fed by smaller streams form fromed rain water collecting over a large surface area.
Deserts often form due to mountains. Moist air from the ocean travels over land, but when it reaches mountains it is forced up. This causes the rain water to fall on the mountains, so by the time this wind reaches past the mountains it is hot and has no moisture left. In time this forms a desert.
But mountains can also cause create an area rich in moisture due to the rivers they spawn, which can form a rain forest like the Amazon. | a2d0fd5b-4b79-43db-9a21-2d5958bad834 |
cfg0sx | how exactly do one way glass work, and how can you see from a tilted glass in a car but can't see from the outside? | It's just a matter of refraction and reflection. "One-way glass" is just normal glass, but usually a little thicker to provide more chance for light to bounce. But basically one side is in dark and the other room is in light. Just like it's hard to see into a house during day, verse the ease during night. The brighter side is having light reflected back at itself making it hard to see into the shadow. | 820e37fd-887e-469c-9403-6e72f31f11e4 |
cfg19c | If humanity we’re to disappear, how long would it take the earth to return to a state of ‘pre-humans’ | I don’t think it ever truly would. We have, for better or worse, changed the landscape of the planet greatly. I am assuming you mean if humans disappeared but all our stuff is left behind. There would be so many problems with nuclear meltdowns, there would be Chernobyl’s all over. Possibly after several eons, all traces of humanity would be gone but I think there would still be fossils or similar somewhere. | bf34c813-ca06-40eb-af65-a02aec254ed0 |
cfg2wm | Why do invasive bacterias/viruses have surface presenting antigens? | Antigens aren't all made on purpose. An antigen is *any* molecular bond that will trigger an immune response. Some of them are just natural products of the way proteins are folded to make cell walls, cell membranes, or viral protein shells.
We deliberately use antigens as a way to screen what is inside of our bodies, and it's a constant arms race. The more antigens our cells have, the harder it is for invaders to pretend to belong inside of us. On the other hand, more antigens also make it more likely that our immune systems will get confused and start attacking our own bodies. Random mutations help us because it means our antigens change a little bit sometimes with every generation, especially the precise combination of antigens that *only you* will have, even if the ones you have are the same ones drawn from a pool of possible combinations.
That means having the *correct* antigens is just as important as not having incorrect antigens. A human cell has a lot of antigens that are unique to humans, but present in most if not all humans. Some antigens are unique to mammals but present in all mammals. When a virus or bacterium is invading a body, it can "hide in plain sight" by presenting the correct antigens and making the body believe that it belongs there.
In the case of, say, rabies, it is presenting antigens that all mammals have. Your cells are all mammalian ^^[citation ^^needed] so your immune cells see the protein shell of the rabies virus as mammalian protein bits. Likewise, a bacterium might escape attack from an immune cell by pretending to be a part of the host's biology.
However, because those antigens or combinations of antigens are usually very unique, the bacterium or virus must also be unique. Rabies can't affect reptiles at all, because reptile immune cells would immediately recognize it as foreign. The same antigens that tell a mammal's immune system to leave it alone trigger the reptile immune system to attack. Many bacteria species and viruses are so unique that they can only affect one species. For example, HIV stands for *Human* Immunodeficiency Virus, and only humans can get it. There are very closely related viruses that affect other monkeys (Simian Immunodeficiency Virus, SIV), but those don't affect humans. HIV is what happened when an SIV virus mutated to be able to affect humans - which makes sense, since humans are closely related to monkeys, so it doesn't take a big change for SIV to become HIV.
Random mutations help the viruses and bacteria, too. Sometimes it works out in their favor and the antigens they end up with look more like the ones of the host they're trying to invade. That's not good for us. Sometimes it works out *really* well for them and the antigens end up looking not like their normal host, but a new host, and the pathogen moves into this new host. That's *really* bad for us because usually it means we have zero defenses against it, because we've never encountered it before. And sometimes the mutations make the pathogens less able to invade, and our bodies attack and defeat them. So a pathogen might have just enough human-looking antigens to sort of work, but it has some leftover antigens from when it was invading monkeys or cows or chickens, and our bodies attack it. | b9d8492f-5ffc-4827-8d18-ddfb6e071f51 |
cfg5cv | why are the tines on corn cob holders asymmetrical? | It takes a lot more force to first pierce the cob than it does to slide the tine in further once it's in. If the tines were the same length, it would take a lot more force to push them both in at the same time. | a8f32f4c-4aac-41c0-ab92-e3480edd56dd |
cfgbnz | What is the legality around a TV film crew filming illegal activities? Like filming heroin production and smuggling across country borders. Or addicts buying and using meth? | 22 years in TV news (US).
When seriously working on a journalism assignment, this not necessarily illegal.
But, as a journalist, one cannot actively assist or enable the illegal activity. It’s important to act as an observer only.
Also, if someone’s life may be in danger, ethics may require you to notify authorities as this exceeds the journalistic value of the story.
There is A LOT more to this discussion with many, many exceptions, situations or levels of illegality that nullify my basic assertion.
But, for journalists and documentarians, there are many situations and examples where recording of illegal activity is not considered illegal. | ef395f71-0d33-4ea5-91ad-a215ba3c8b69 |
cfge6q | Do artificial sweeteners work on insects? Could I use diet soda to kill off an ants’ nest? | I mix up about a teaspoon each bicarbonate of soda and icing sugar with a little water and leave it near where I see ants most. They can't separate the sugar from the bicarb so take it back to the queen anyway, which kills them all.
Apparently, ants can't fart and bicarb causes gasses inside the stomach. So the ants explode, I've read somewhere. | a306b894-096a-437e-82a1-7644732682a6 |
cfgect | What is TIME? | “Time” is the process of change. We observe the passage of time when we watch a process take place, such as sand falling in an hourglass or a planet completing a circuit around the sun.
Look at it this way: You turn an hourglass upside down and watch the sand fall. The hourglass changes its state in that it takes an hour for its atoms to re-arrange into a new configuration. You say that one hour has passed, because humans arbitrarily decided that one turn of the hourglass marked an hour. Even though the length of the hour was arbitrarily chosen, the fact that the sand moved from top to bottom is an observable, repeatable, predictable phenomenon.
There is no past and no future, in the sense that these are not places you can visit. There is only the present. But we definitely know that the ‘present’ changes shape and arrangement, and this is what we are observing when we talk about ‘time.’
If there were no humans time would indeed still pass, although there would be no one around to quantify it. | 44b8b518-4098-48ce-a718-d385197857fe |
cfgkrm | Why do movies have deleted scenes? | Editors have to ask questions like whether a scene properly moves the story along, whether it's necessary, or whether it adds too much length to the movie. A children's movie generally needs to have a shorter length than a movie for adults, because children, especially small ones, have little attention span and tire easily. The scenes you mention are probably perfectly fine, but may not be necessary for the story to progress and may make the movie too long. | 33369b7e-6e9f-4b65-9678-90a4bd715d2b |
cfgl9w | Why don’t you have to split white and coloured clothing in laundry anymore? | You do. Coloured fabrics can bleed the first times you wash them, and discolour whites.
If everything in the machine is old and washed several times, no worries, mix them. Bit with new clothes, always separate, even one new sock can really ruin your day. | 922aea89-f1fd-4b2d-b128-fcb65e57fefc |
cfgphd | How does sustainable forestry work? | Tree farms tend to work pretty well. Where I live in the Southern US (Georgia) there is a large lumber industry. Everywhere you go there are free farms. Mostly long needle lines. A vast majority are planted pines.
Basically a lumber company can buy out 20 tracts of land and cut one per year. Each time they cut down a tract, they plant trees equal to the number they cut down. The next year, they move to the next tract. So on and so on. By the time its year 21, that very first tract has had time to grow to the size they need and the process repeats itself.
I don’t know if planting a straight tract with only one species is more beneficial than mixed growth, but it does help with consistency of the lumber. | c60f120f-c299-4233-9ba2-3ba7d3145389 |
cfgphn | What is ASMR exactly and how is it supposedly pleasant to the ears? | This is the best answer I've ever found.
_URL_0_
Plus it comes from a great comic to read. | bb75caac-8970-416f-ad36-15d5036f47de |
cfgxg2 | What actually happens when you "lose your voice"? | Our ability to speak and make other sounds comes from our vocal chords, which are [flaps of tissue located in the larynx](_URL_0_) vibrating. Hoarseness or "losing your voice", also called dysphonia, happens when the vocal folds can't vibrate properly due to inflammation from an infection or overuse. There are obviously other reason's you can lose your voice but I believe based on your question you're asking about temporary hoarseness and not something like paralysis or cancer. | a6c0b679-a1ec-47d9-ae25-7e3d5850152e |
cfh624 | why helmets have an expiration date and how their effectiveness is reduced | helmets protect you by absorbing the kinetic energy (vibrations) of an impact. They do this using specially designed styrofoams. Styrofoam breaks down over time due to the oxygen in our atmosphere. Eventually, it breaks down enough to stop safely protecting your head. | 7aa2c02e-f265-46e7-84c9-6ac971921ec7 |
cfh7j0 | How does alternating current work? | So let's think of a circuit as a a bunch of people holding hands in a circle, each holding a baseball. Direct current is each person constantly passing the baseball to the person on their left. Alternating current is giving your ball to the person on your left, then them giving that ball back you, then you give it back to them and on and on. [This gif does a really good job of showing what I just described](_URL_0_).
AC isn't strictly better than DC, it's just depends on what you're doing with it. For many applications, DC is either better or even necessary. For power transmission, traditionally, AC is more efficient because you easily change voltage and current with AC using a transformer, but even this isn't always true anymore. | 0192e2bf-c807-4215-84ec-6f7aa59bd15d |
cfh85o | how do calculators actually work? | Calculators are complicated circuits operating in binary. Binary is a way of counting using only two numbers, 1/0: 0000,0001,0010,0011...
For simple operations the calculator utilizes a so called full adder: a circuit that compares 3 inputs to two outputs.
You can imagine it like written addition. There are 3 inputs: x,y and carry in/over.
X and y are decimal places of your compared numbers, and ci is the carry out of the last decimal place.
You start comparing the first number,
if in=0: out & co=0,
if in=1:out=1 & co=0,
if in=2: out=0 & co=1,
if in =3: out=1 & co=1.
Then you put the next decimal point in and put co into ci.
Repeat that until all decimal points are accounted for and save all output bits. That's your new number. It gets way more complicated when subtracting and multiplying, but they are all based in adding. | cd1684cf-c66e-4f39-96f7-6470e6005199 |
cfh86s | Why aren't species that have huge populations, like humans or bugs, having a commensurate number of mutations and thus branching off new species? | 2 reasons. First is that simply, not enough time has passed. Modern humans have existed for about 200,000 years. That's simply not enough time for speciation to occur. The second is that we don't exist in isolated populations, which is how speciation occurs. Humans from all over the world are constantly exchanging genetic material by producing offspring, so, with few exceptions, there are no isolated population that exists to diverge. | ea6e4c14-fdc2-45f1-9cee-72753ff73591 |
cfhdx8 | Hypnic Jerks. | I'm pretty sure I've read that they exist because our ancestors used to sleep in trees and if they fell asleep in the wrong position they would fall unless they woke up in time to grab a branch and save themselves. So it's your body's vestigial reaction to you feeling like you're falling out of a tree.
Could be wrong though. | 9242af2e-6fb0-4653-be64-d9640f45c3c2 |
cfhg75 | Why are there bacteria that can break down Styrofoam? | Nutritional value as we know it is measured for humans. We need sugars and proteins and the like. In theory, if it can be burned, it can be food for an organism. Pretty much all of the life that you can think of consumes oxygen, reacts that oxygen with hydrogen and carbon, and releases water and co2. The hydrogen and carbon come from food. If it were not poisonous to us, and if our gut bacteria were the right kind, we could survive by eating styrofoam and drinking gasoline. These bacteria are simply optimized for doing that, while our gut bacteria are optimized for digesting "natural" foods like meat and berries. | f0ef13d2-4737-4430-b6b4-3815a3763dbc |
cfhk9d | What causes sleep talking and sleepwalking? | As I understand it (and this is not my area), your body is supposed to release hormones/chemicals of some kind when you sleep that essentially paralyse you and stop you from acting out your dreams. Sleep walking/talking are the result of this process failing, so you're just acting out what your brain is processing in its sleepy state. | 0d409d89-5917-46f4-831d-91678d0af742 |
cfhtcj | What’s the difference between infant formula for 0-6 month olds and formula for 6-12 months old? | It's essentially a marketing ploy and therefore depends on the manufacturer. There is a single set of FDA (or equivalent) requirements for infant formula, but the age-specific formulas may have differing amounts of vitamins, corn syrup, etc. It's perfectly fine to use newborn formula until 12 months (at which point babies should ideally be consuming family foods and have no need of formula, though they may still be breast fed).
**Update**: here's some [medical advice](_URL_0_) confirming this
> Research shows that switching to follow-on formula at six months has no benefits for your baby. Your baby can carry on having first infant formula as their main drink until they are one year old. | 25cf469e-b43c-455e-8bd4-3a58d22e00bc |
cfi4k6 | what am I doing and why does it work? | “Hi I’m Chris Hanson. Have a seat.”
But fr I used to design a pair of sneakers in my head done to every little detail. A pair of Air Force ones to be exact. Something about the little details got me | ad55ebb8-8e52-4e95-abb0-041c874384e2 |
cfi5fu | What is the difference between normal steel and galvanized steel? | Galvanizing is a process of adding a zinc coat to the steel. It should make the nuts last longer and prevents rust.
The actual process is slightly more complicated but this is essentially it. | c60bf8be-d4ab-4aca-a22f-73b60350f76a |
cfidip | How do archeologists and paleontologists look at a specific bone and figure out what animal it belongs to? | It's a game of elimination really. Scientists can date a bone so you know roughly white time period any given fossil is from. That excludes any known animal not around in that time period.
You can compare the bone to any known animals alive or dead. If you find a close match, you can start looking into more detail to see if it's an exact match. Even if you can't find a match, bones are shaped by their function. If this bone is not a match but similar to bones of existing or other extinct animals. You can get an idea of the function and placement of this bone in the animal's body.
There's a lof of animals that we have no clear idea of what they looked like because all we found is a single bone. If we ever find more, we can expand on that knowledge but until then, they're a mystery. There's more than a few dinosaurs that have cryptic names that refer to the one body part we found of them. Animals whose names translate to 'terrible claw' and things like that.
And to make it even more complicated, animals sometimes undergo significant change as they mature for from juveniles to adults. It happens that we adjust our expectations and two different species actually turn out to be the same species. Just with significant differences between male and female or juvenile and adult. | 6ce49fc8-7eaa-4751-a8b7-47bda50119a2 |
cfiueq | Why do TV shows and movies have opening credits if the credits are shown at the end? | Opening credits are advertising, both for the major companies producing it and for the movie or show itself. It's part of the 'star system' where big names are promoted, and used to promote future works.
End credits are more about documenting the rest of the cast and crew. | 4fbfd980-21ed-4539-85b4-91f08ab71fd0 |
cfjdf6 | Why does cold water intakes more CO2 than warmer water and it holds it better? | It's true of most gases and most solvents.One of the best ways when it is necessary to degas liquids for lab use is to agitate while heating to a little below boiling point.
> Increased temperature causes an increase in kinetic energy. The higher kinetic energy causes more motion in molecules which break [bonds holding the gas molecules and they] escape from solution.
> _URL_0_
> _URL_1_ | d5c4894d-6aac-48ed-96e7-40a04c375818 |
cfjlr2 | How do cows get their nutrients if all they eat is grass? | So someone asked this earlier and then deleted their account so here we go again. The grass. We don't get any because our digestive system can't break it down into a useful form but because cows have 4 stomachs they can | c4a59a4b-2a9a-4bad-a2e4-f32f11f1375c |
cfjq8r | How and why does milk help soothe the burning sensation after eating spicy food? Why does water make it worse? | It actually has more to do with the chemical that makes food spicy, capsaicin, being soluble in fat. It dissolves into it and gets pulled away from your pain receptors in your mouth. There are many other fatty and oily foods that work too.
_URL_0_ | 12aac5ae-882a-4158-8b3a-cbaf8eec01d0 |
cfk2pt | Why, despite all milk producing mammals did human chose cow's milk? | Domesicatability.
Humans consume several different species milk including goat and sheep, but cow milk is particularly popular because of cows predilection for domestication. Cows are easy to farm, therefore they are cheap to farm, therefore cow milk is cheap source of protein and nutrients, therefore we consume lots of cow milk. | e780ada7-fd21-4c1c-8029-4dc06712897f |
cfkjm3 | Why do they say not to use your phone while gas is being filled in the car? | Static charge and electromagnetic radiation (radio waves) *can* cause fuel to ignite. But your phone is not putting out a very high amount of energy at all, and the fuel pump systems these days are very well protected, so the chances of that happening are probably worse than the chances of winning the lottery.
This idea is much more serious at military bases where high-power radar poses a hazard to certain types of jet fuel. | 529eb8da-3b87-4e40-8514-6c240e998040 |
cfl2ju | Why does soap clean your body and yet make the shower filthy with grime at the same time? | Soap dissolves fat, making it easier to wash of. However soap dosent magically teleport away fat. The fat is still there. It's instead dissolved in a mixture of dead skin cells, soap and water. Which gets stuck to the ceramic | 2c74eaf1-4129-480f-be4a-f2238986da74 |
cfl9hs | How does flicking a switch on a bicycle's handlebars cause it to change gear? What mechanism moves the chain to a larger/ smaller gear? | If you take a look at your bike, you'll see cables snaking from the switches on the handlebars down to each set of gears -- specifically, to a little thing attached to each set called a *derailleur.*
Assuming a mechanical derailleur (there are some that use motors to achieve the same effect), pushing the button causes the cable to either release or take up more slack; that slack (or lack thereof) causes the derailleur to slide from side to side. This, combined with the physical act of pedaling, causes the derailleur to nudge the chain until it either falls off the gear, or slides up onto the larger gear. | 8d621280-7096-4afd-a9d9-0ccc0714ec86 |
cflh33 | We can tell the age of trees by the rings in the trunk and fish by the rings on their scales. What's a scientific way to tell the age of humans? | Generally teeth are a rough indicator of age, and things such as skull and pelvis size are used postmortem to determine age. None of these are 100% accurate though.
Sorry that's a bit of a non answer but I tried. | ac545b73-afde-4385-8191-0f94b3d5cc7e |
cflifu | Why does fog only appear in certain areas and not others; e.g. fog appears every night at one end of a local street but not the other? | Fog means you can see water droplets = condensed moisture in the air, as fine droplets
It implies there's no wind (it would blow away) ; And the temperature is low enough for the moisture to condense into water droplets
At one end of the street it may be too windy (fog cannot accumulate fast enough to see it) ; or the temperature isn't low enough for the fog to actually form yet | 0146d69e-ba1b-43bd-8d41-9238f324e833 |
cflqc8 | Why can't surgeons just pull out huge chunks of body fat at a time with a glove or a modified vacuum hose? | The fat isn't just floating inside you. Its attached to your organs and blood vessels. Tearing at it is gonna cause issues. | 29452c5c-cae1-4f31-b767-534580faac49 |
cflt54 | Why do they say it roses are red violets are blue when violets are not blue? | For most of history there was an English word dedicated to violet, it was just called royal blue. I don't remember why we got the word violet, but the rhyme didn't use violet because violet didn't exist as a word. It's like how dinosaurs weren't called dinosaurs before we invented the word dinosaurs. | d9435a99-c801-4a70-ac5a-311f27ec6ea2 |
cfltxv | How could single payer public healthcare, and the increased taxes incurred, ultimately cost less for individuals than private insurance in the US? | The insurance companies sit between people and medical services. Single payer reduced the number of middle men who process claims and all that. Let’s middle men = less money being paid to them = cheaper overall cost
Also the idea is to get more people and corporations to pay in (taxes) thus spreading the cost.
Last I think there’s something about more competition. Right now I can only see certain doctors because of insurance. If I could see anyone it means doctors/hospitals have to be competitive (I may have imagined this one so fact check me) | 36d58929-493e-46ca-8c2e-f57782442178 |
cflvn5 | How does limiting withdrawals to $10,000 help prevent money laundering? | As far as I understand, the law doesn't *prevent* you from withdrawing more than $10,000 in cash. It just obligates banks to report to the government that you did. Also, the same "anti-money-laundering" law established reporting standards for both deposits and withdrawals. It's more obvious why mandatory reporting on large cash *deposits* would help to prevent money laundering.
In general, the government wants to make it hard for people who work in illegal industries to make use of conventional banking. Even if you have a very effective money laundering scheme, withdrawal rules will still make it difficult to use that money for further illegal activity. If you plan on paying $20k for a shipment of drugs, you want to keep that money as cash rather than laundering it. | 7f86d8ea-614a-4f9e-ab56-d132df735c33 |
cfm4o3 | Why are honeycombs hexagonal? Why not triangular, circular, etc.? | All cells start out circular when the bee draws it out with her wax. Once it has been joined with an adjacent circular cell, the wax is heated and it melts into a flattened shape, becoming hexagonal.
[Study done on this subject](_URL_0_)
The cells on the open edges of honeycomb are rounded.
I'm a beekeeper and a while back, I wondered about this too. | b3f329fc-7244-4cf2-9e77-2e4bb20636cd |
cfm6lx | if e.coli is already present in ones colon, why does it make you sick to ingest? | There's harmless e. coli and there's harmful e. coli. The ones chilling in your intestines is harmless. The ones that make you sick are harmful. | 09a39e1d-ac3f-4599-b0e2-9a10fd0aadd7 |
cfmg9x | How do the manufacturing companies ensure that the insides of the food packaging packets are thoroughly cleaned ? | Depends on the package, but there is usually some sort of cleansing step right before filling and sealing.
Take bottles for instance. On the bottling line I worked at a brewery, empty bottles first entered a sanitizing machine that flipped them upside down and blasted them out with peroxide and water, then were filled and sealed within seconds.
Plastic bag type packages usually come off a huge roll of what is basically a plastic tube. It was manufactured in a fairly clean environment, and it is pretty much impossible for stuff to get inside until it comes off the roll and is cut, filled, and sealed in seconds. | 32dfe0d5-39a1-4b32-981e-409c5e411a18 |
cfmkz9 | Why do us humans eat less during a hot summer day? | Digestion requires your body to some work, which generates heat. Carbohydrates (starches and sugars) are easy to digest and don't produce much heat, proteins are harder and produce more heat, fats are in between. | 63439fa0-af5c-484c-a661-142ca0139fc8 |
cfmmtl | why do your ears pop when you're on the highway and roll up the windows? | I'm fairly sure it's because having the windows down creates negative pressure in the car, and closing them equalizes it?
Something to that effect. It has to do with a change in pressure from the air moving past the car and pulling air out from inside, and closing the windows blocks off that suction | f9f22ca0-e9d8-439f-9aab-6c0b0da777ea |
cfmqbb | how does your body tell you that you are hungry? | do you mean the symptoms of being hungry or the mechanics of the sense of hunger (yes hunger can be scientifically classified as a sense, we apparently have somewhere between like 10-50~ senses...) | cee1ec4d-2b8c-4a6a-89d3-f62282df6c6b |
cfmqsm | Why are bleach bottle caps so loose? | Are you talking about the child-safety feature, where there is an inner cap and an outer cap and you have to squeeze or push down on the outer cap in order to make the inner cap turn (in the loosening direction)? If so, that is a child safety feature. | bec851ad-e335-4f12-a617-2d76ecac1076 |
cfn1sv | What happens the the white/clear puss that fills a pimple if you refrain from popping it? | it either bursts on its own at some point, often when you are asleep. Or it gets slowly broken down by your immune system at a rate it can handle safely, at which point the extra material making up the pimple slowly shrinks, dries up and falls off. | 7f2b27bc-0d54-4b0c-83a3-4e77ab7db74d |
cfn4gq | why can a high speed 4g signal reach me anywhere but wifi has trouble reaching me in the next room? | There are 2 factors to consider.
First is your surroundings. Radio waves, like a 4g signal or wifi are just electromagnetic radiation, like light. They pass through some things well, but are blocked by others. Having multiple walls, or a big HVAC unit, or a metal building between you and the transmitter can block either signal. Compare that to being outside, where your phone might be on direct line of sight with the 4g tower.
The other thing to consider is the size and power of the cell tower transmitter vs your wifi router. A cell tower transmitter can be bigger than a person, with a dedicated high voltage line supplying enough power to transmit signal for miles. Your wifi router is much smaller, plugged into a wall outlet, and only designed to transmit 100 feet or so. | 6bbf2dc5-c8df-4218-97bb-1cfe0db1b08c |
cfnm29 | How do vinyl record players know what sounds to make just by running over the grooves? | Think about phones: when you talk into a phone, a membrane inside the phone vibrates according to your voice, and uses a special electric circuit to transform these vibrations into an electric signal. There are many ways to make this kind of circuit, but the general idea is that you can transform specific movements into a specific signal. Then you just have to reverse the process and voila, you got sound again!
Record players work very similarly, but the tiny movements are recorded by the grooves on the record. When the needle passes on the grooves, its other side vibrates in the exact way required to make the sound you want.
So how would you make a record? Well, just put it through the reversed process! Feed the signal into the machine and led the needle “carve” the correct grooves into the record.
While this isn’t the exact process, it gets the gist of what’s happening.
The cool thing is that there isn’t anything special about record players and vinyl: this works with pretty much any reversible process. | f6357347-2d83-44c7-a0a0-1d62102f6b58 |
cfnu5f | why do magnets lose their magnetism over time? | Keep in mind that perfect magnets do not lose magnetism over time or use (for the same reason Earth does not "lose gravity" if you jump). It is not an intrinsic property of permanent magnets.
Magnets losing magnetism instead has to do with imperfections in their construction, and mechanical and thermal wear-n-tear. | 022cd3ad-9daf-4902-aa1b-d004eed32791 |
cfnuc5 | During the Apollo missions, what is the purpose of the "beep" you hear regularly in the background? | They are called Quindar tones and they served to turn the transmitter on and off such as with push-to-talk. The issue is that to keep track of the astronauts from a rotating Earth required a worldwide network and frequent switching between transmitters and receivers. The tones mediated all that, so they should in general follow when people are talking. | ec3d70ae-94b9-45ac-895e-c9d89e45dbd2 |
cfo2u4 | How can we determine about dinosaurs' looks just by their skeletal remains? For example, one cannot imagine humans having boneless parts like ears just by looking at their skeleton. | Very possible. For example, it took quite a while before we realized many dinosaurs were feathered precisely because there wasn't a ton of fossil evidence for that being the case for quite a while. Nobody really knows for sure what dinosaurs looked like. What we have now are educated guesses. The guesses get more refined and closer to the truth all the time, but in the end there are likely always going to be blind spots we can't fill in the gaps for.
Looking at their closest reletives does tell is what traits they probably didn't have though. For example, most reptiles and birds don't have boneless "earlike" structures in the way mammals do. We can pretty safely assume they likely didn't have such structures. | ce668441-92d8-4f1a-ba9a-a86f1ef3c1d9 |
cfo3fy | Why do pigeons not get dizzy when shaking their head. | They're actually keeping their heads still while they're bobbing!
If you focus on their heads, between the bobs, their head and thus eyes are fixed in the same position while their body moves. When they move too far, they have to bob their heads to the next fixed position.This is to keep their vision still to detect any movement. If they moved their heads with their body, everything will blur when they move so they can't tell if the movement is motion blur or a predator. | 5ee6fad5-8e6b-4462-b26a-cd8c06f9a7e9 |
cfo90m | If you were able to shoot a bullet perfectly straight in the air , would it come down at the same spot or would the earth's rotation effect it? | Let's isolate the variable from confounding factors. Let's fly to another planet, with no atmosphere, which is not rotating. On this planet, you can fire a bullet directly up, and it will fall directly down. No questions asked.
Let's fly to another such planet, but one that is indeed rotating. From that surface, we can shoot a bullet directly up, and it will attain an altitude before it begins to fall. At this altitude it will achieve zero vertical speed for just a moment, in between its rise and fall. But it will still have a horizontal speed caused by the horizontal rotation of the shooter-and-gun-and-bullet on the surface of the planet. In the absence of an atmosphere, this horizontal speed **will not change**.
But a circle around the planet at that altitude is not the same circumference as a circle around the planet's surface. Therefore, though the horizontal speed of the bullet did not change, the *angular speed* of the bullet (degrees/second or radians/second) **will not** remain the same. The angular speed is decreased at this altitude.
The angular speed of the bullet will lag behind that of the shooter, beginning as soon as it rises above him. This lag will be greatest at the bullet's highest altitude. And the angular speed will equal that of the shooter when it returns to his altitude, but the bullet has already lagged behind the shooter, and won't be able to catch up. | 9fbeee93-3bc6-476a-a12a-c583353cc8e5 |
cfo933 | Why do ceiling fans that are used more often collect dust quicker than ceiling fans that aren’t used much? | Air flowing over a surface builds up static charge. The static buildup attracts dust to stick to the moving fan blade.
Also, a spinning blade will pick up any oil or grease residue launched into the air from cooking. The dust will stick to the sticky residue and can build up over time. Same thing for tar residue from smoking. | f845e74c-2125-4194-b3a9-7d818e744b7b |
cfoih7 | Why does pouring hydrogen peroxide on wounds sterilize them and sting? | The hydrogen peroxide kills germs and living cells. It can delay healing and leave scars, so it isn't recommended for cleaning wounds. It is a powerful oxidizer and if undiluted, it would cause severe burns. | e43c680d-ee2c-40bc-9d36-fd44c33a67a3 |
cfondc | What would happen to the earth if all the whales were gone? | ELI5 does not allow hypotheticals. Questions like this are better in r/asksciencediscussion. | 1969e817-ff47-42d4-b1ee-b3c610a8beac |
cfopqe | Inmune privilege of the eye | In the event of an infection, most parts of the body send blood to those areas, causing what you know as swelling. This blood carries white blood cells and oxygen to the area in effect to help kill off the infection and kickstart the healing process. The eye, however has a special circumstance, in that intraoccular (inside the eye) swelling would cause loss of vision. This is where that immune privilege comes in. While the mechanics of it all are still not yet understood, even under circumstance of infection, the eye will not swell up, as part of some other related mechanism which intentionally works to keep vision working ‘at all costs’ if you will.
What is known about this are three basic mechanisms.
First: physical barriers which limit or suppress the free flow of cells (blood cells and other immune-competent cells) into and out of the eye.
Second: The ‘inhibitory microenvironment’ of the eye, which contains immunosuppressive (limits or decreases immunity/immune reaction) cells and other properties.
Finally: The eye itself regulates localized immune response.
[Here is a non-eli5 article ](_URL_0_) if you’d like to read into it further. | 3ffd8f2d-0ebe-4b67-b764-bd3e018a55e4 |
cfovzb | how exactly do some antibiotics and other drugs make you more sensitive to sunlight | These drugs have certain structures that absorb radiant energy (UVA or UVB from sunlight) so when photo-activation of this drug occur there will be excitation of electrons in your body (from stable to excited state), after returning back of electrons from the excited state to the original stable state they transfer the energy they acquired to oxygen which leads to formation of reactive oxygen intermediates that can damage DNA and cell membrane, there will also be activation of some pathways that leads to formation of cytokines and other inflammatory mediators which results in an inflammatory response that appears as an exaggerated sunburn reaction. | be09a984-77ca-486c-905f-231b934a1f44 |
cfp5z5 | if identical twins are genetically the same, how do they get different fingerprints? | Fingerprints are not generated genetically. Fingerprints are generated when we are in the womb from pressures present on the fingers.
2 people can have similar to even nearly identical fingerprints as well, in fact the chance of 2 people having the same fingerprints is about 1 in 64 million but when you have billions of people on the planet, well, it becomes pretty much bound to happen. | 137f0bfd-5fc2-45c7-a521-f5bd4bd8db29 |
cfpaaz | Could you angle series of lasers and fire them into an object, mirrors, prisms, or something to focus and then combine them into one powerful beam? | No, because the reflection of light is by its nature reversible. If you shine a beam into a prism and measure its output angle, shining a different beam back into that same path will come out the same direction as the original input beam.
If you COULD convert multiple beams into a single coherent beam, it wouldn't be possible to reverse each portion of the output back into its individual source beams.
You can focus them so they all land on a specific point, but only at a specific distance, like how a magnifying glass has an "optimum" viewing distance from an object before it comes out of focus. But you can't make a magnifying glass, binoculars or telescope that never needs focusing. | 1ac2cc24-bb98-4a96-b07d-55e3766eb9d3 |
cfpaby | What’re the good and bad things that came from the Affordable Care Act and why is it such a landmark of politics? | **The good:** People without insurance got insurance, and insurance companies are no longer allowed to fuck people who have 'pre-existing conditions.' You have to understand that in the past, a person could pay their insurance premiums for years and then when they got a real illness (such as cancer) the company would go digging through their records and use any imaginable excuse to prove that it was 'pre-existing.' (eg: "Oh, you complained of fatigue five years ago? We won't cover this bill. Have fun with bankruptcy.") It was also extremely common for people to get care denied when they were travelling. Or for no reason at all. They would literally deny a claim for no reason and make the patient to go to court to force the company to pay. It was insane.
**The bad:** First, for an insurance program to work the healthy people have to pay for the sick people. Then, one day, those healthy people will get sick and need someone else to help them. For this to work, the ACA mandated that EVERYONE has to buy insurance or pay a tax to defray the cost of healthcare. It's really the only sane solution, but people got mad about it anyway. Additionally, health insurance costs are based on risk assessment. When the government began dictating that insurers could no longer fuck people, this threw their assessments off. So prices became volatile and people saw unaffordable rate hikes.
So if you are a healthy or wealthy person or an insurance company, you probably weren't happy. If you were a person with low income and dire medical conditions, you were probably very happy. But then...
**The ugly:** When the ACA was passed, Republicans lost their goddamned minds. It wasn't a matter of sharing costs or fixing the health care industry. It was an attack on our FREEDUM! It was EVIL and UNAMERICAN and TREASON! Never mind the fact that it was a Republican idea to begin with, the Republicans HAD to oppose it because they had already decided to oppose anything Obama ever did. So they spent YEARS voting to rescind the law in symbolic votes, but when they finally had the power to actually change the law, they had NOTHING. Absolutely NOTHING. Not one goddamned thing. Even when they had a majority, they STILL couldn't get enough votes to repeal it. Which proves they had been lying the entire time, and their resistance to the law was a giant steaming load of bullshit. | b0f837f6-f722-4fd3-8650-044e738790c8 |
cfpalb | why do goats have horizontal pupils? | Wider field of view, I believe. It's like how predators have vertical pupils, it narrows the light coming in so they don't get distracted as bad since their periphery vision is so small.
Goats are the opposite, and having wide set, wide pupil eyes means they have a maximized horizontal field of vision, which means they can best see if a predator is sneaking up on them from any angle. | 00671647-37f8-45c8-9e1a-cde56ff57dbd |
cfpem6 | Do wasps inject the same amount of venom with each sting? | Yes they do run out. They have a sack of venom near the stinger. The amount it releases in each sting will varry until the sack is empty. Usually its empty after 2, 3 stings | 4e3be5a2-b74d-443b-b1ce-c4d9af215794 |
cfpeq5 | Why do some birds mimic the songs of different birds? Wouldn't that make it harder to find a compatible mate? | Some highly intelligent birds will mimic any sound they hear. I used to work in animal care and we had an African Gray that used to be next to a pool, it started mimicking the lifeguards whistles and calls and had to be moved because it was causing false emergencies. It was moved to a merchandise location and was soon mimicking the sounds of the cash register.
Mimicry in nature is often used to represent a animal that is larger or more aggressive. For instance a parrot can still be preyed upon by hawks but if the make the calls of an Eagle or a crow (flock animal, that protects its territory) it may scare the hawk off. When a potential mate is around or being sought out they easily switch back to their normal calls. | 03c2dca9-d893-4680-aa70-ff51f28f803c |
cfpn12 | How chemical sunscreen absorbs UV ?light? | Instead of physically deflecting UV light, these molecules absorb UV radiation through their chemical bonds. As the bonds absorb UV radiation, the components of thesunscreen slowly break down and release heat.
~_URL_0_~ | 35af1774-ba07-4129-9d5b-b6a76de8882a |
cfpr1p | What's the hissing sounds made by semi trucks when they stop? | The brakes are air assisted. The hissing sound is when the driver lets go of the brake pedal | 83dfd218-58b1-40e8-b70f-4d52e81ff9ad |
cfpruz | How do you know how much cash it will take to fill up your car and what will happen if you give the clerk too much cash? | They refund the overage amount. So if you give them 20 but your car holds 10. Go back inside and they'll give you the other 10 back. | c3b2282e-c5d3-4606-b1af-db852dd4058b |
cfpsqh | Is strength reliant on volume of muscle within the body? If not, how does the strength to volume ratio work? | Also how that volume of muscle is distributed along the skeletal frame is important. The physics of leverage and hinge points is definitely a consideration when it’s comes to applicable strength. | fffa9d17-4b8a-42e9-a66b-c2540d5164f3 |
cfpssq | Why does brake fluid need to be changed even though it never really "runs out"? | Brake fluid absorbs water. When water gets in to it and the brake line pressurizes, the brake brake fluid can get hot enough to turn the water to steam. Steam can compress more than the brake fluid, it can cause your brakes to fail when water is in the brake fluid. It usually happens when you brake really hard. | 8528abd1-efab-4993-8fd4-584626a8aff3 |
cfpszg | In old CRT's why does physical damage to the tv cause the picture to rise, disappear, and then reappear in that order constantly? | The picture on a CRT is made by a beam of electrons from an electron gun hitting the screen and making tiny dots on the screen glow. The beam scans left to right for each row of the image, and then jumps down to the next row, until it reaches the bottom of the screen and starts over again.
At the same time, the beam constantly changes in strength: more electrons make a brighter spot on the screen. There is a short period of time between when the beam hits the bottom of the screen and when it hits the top again during which no electrons are shot out of the gun.
In order for the image to appear properly centered on the screen, the moving of the beam has to be synchronized with the strength of the beam. In older TVs, this is done entirely with analog circuits having adjustable components. Hitting a TV can knock one of these adjustable components a little, causing the TV to lose sync. On these old TVs, there is sometimes small screw adjustors on the back: V-sync and H-sync. turning the V-sync will fix the problem. | e0517ae2-bbad-4b93-99bd-66cb5aa6f859 |
cfpu4i | How can a neutron decay into an electron and a proton? | Particles are perturbations of the underlying fields, and many physical processes produce or destroy particles via one of the interactions interacting with one or more fields while preserving total energy. The weak interaction allows quarks of different charges to be transformed into each other. The neutron decay process is `n - > p + e- + νe`, with a down quark turning into an up quark. This process conserves all the required quantities. The inertial plus kinetic energy of the decay particles are equivalent to the energy of the neutron, as a neutron is slightly more massive than a proton. In fact, free neutrons decay with a half life in minutes.
& #x200B;
If you want to get a bit more in depth, neutron decay is actually two steps: a neutron decays into a proton and a W^(-) boson, a process mediated by the weak interaction. Then the very short lived W^(-) boson decays into (generally) an electron and electron neutrino also by the weak interaction. It can be represented pictorially as a Feynman diagram: [\[1\]](_URL_0_). | bd7595ba-3a92-4112-a402-e5a85e8799d2 |
cfqbxi | Does recycling plastic really make much of a difference? | My interpretation of this is that though the costs of sorting, melting, and recasting the plastic are roughly equivalent to (if not greater than) making it fresh, the real green effect is from the waste plastic not being tossed willy nilly and damaging the oceans and whatnot.
However, when the oil starts getting really scarce, recycling will be very effective as we won't have the complex hydrocarbons required.
As a fellow redditor pointed out, aluminium is much better for recycling! | b95eb103-6bda-4c37-a920-8373a770c83f |
cfqcbp | what is a normal day of food for you? | Google greek food or mediterranean food...
Basically no or little processed stuff or sugar. Lots of veggies and lean meat. | 6fdfc910-02c9-451f-ba53-79fdbcdfb0ed |
cfqmwj | Why do cargo planes such as the C130 and the A400M use propellers instead of jet engines? Wouldn't jet engines be more powerful and allow more weight to be carried over a larger distance? | They do use turboprop engines which are turbine engines that turn a propeller. The turboprop is more efficient at lower speeds and altitudes than the turbojet. | 0581d9f2-b587-4cc9-8ad4-bfbe15a0e519 |
cfqpka | How come when we float, is easier to float face down, then face up? | The biggest areas of low mass, the lungs, are closer to your front. With front down they displace more water and seem to push you up more. | 6eb87d17-b001-4355-9875-77ee04cbb05e |
cfr4aq | If mammal brains all have roughly the same structure and systems, why do drugs work so differently between families and species? | When it comes to the brain, effects come down to the receptor physiology (aka the exact shape and function) of the neurotransmitter receptors on neurons.
Even slight differences in receptor physiology can have huge effects. For example, if one person has a dopamine receptor that lets dopamine bind slightly better than in another person, chances are that these neurons will be stimulated easier. Following this narrative (again, totally hypothetical), it may make this person more susceptible to addiction because more stimulation by dopamine is more pleasurable.
This is why all people respond to things (meds, drugs, stress, etc.) differently despite having extremely similarly sized and shaped brains. It's also why many neurological and psychiatric diseases (epilepsy, OCD, depression, etc.) exist. It's unfortunately also why many of these conditions are so difficult to treat; we have a finite number of medications but a near infinite number of potential receptor physiologies to account for.
Hope this helps. | 6080a06c-f2a2-49a6-a228-d27e96874bbb |
cfr4u3 | What are the differences between Patriot air defence system variants? | GEM stands for Guidance Enhanced Missile.
GEM/T - the T stands for TBM (Theater Ballistic Missile). The missile has been optimized to shoot down ballistic missiles.
GEM/C - the C stands for cruise missiles. The missile has been optimized to shoot down cruise missiles.
GEM+ - an upgraded missile capable of targeting both ballistic and cruise missiles | fa426f65-df1a-4a3b-8603-b67e9b07da5c |
cfs227 | What are the differences between different types of toothpaste (eg whitening vs enamel strength vs gum repair) and why doesn’t one toothpaste just do everything? | Dentist here. It's the additives. Pretty much all toothpastes are an abrasive and fluoride. The abrasive is to amplify the efficiency of your brushing and the fluoride to help fix the damage caused by the acid erosion from the bacteria. Under the enamel is the shock absorber of the tooth, dentin. The dentin has a matrix of water tubes originating from the root of nerve and blood supply of the tooth.
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Everyone has a different thickness of enamel, sensitivity of the dentin, size of the pulp chamber etc.
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The different toothpastes are made to focus on the individual's marketed advantage. Do you have gum disease? How about a toothpaste with an additive that will kill more fun disease bacteria? Want whiter teeth without paying for whitening? Want that old wives baking soda clean that got grew up knowing worked? Maybe a cool mint before bed because the strong mint wakes you up? Do cold things bother you? How about a toothpaste that will seal up those dentin tubules to make the tooth less sensitive?
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As you can see they have made a toothpaste for pretty much every preference. As a dentist, they all work great, except the charcoal. That will ruin your teeth. | 8c67dfa6-f118-4d0b-b959-ffbdad4c16bf |
cfs9im | Physiologically, what is strength and where does it come from? For example, there are two men who are the same height and weight with almost identical builds. Why can one of the men bench 250 Lbs. and the other can bench 300 Lbs? | Strength is a measure of how many muscle fibers you have. Muscles are built from little repeating units and stronger muscles have more of them and can generate more force | 1ccf69d4-42e7-4306-acc7-c5ffa3c8d1cb |
cfsbsl | If the clitoris' only function is giving pleasure, was its development a mere biological accident? | Not necessarily, by making sex and therefore reproduction more pleasurable it could help incentives early humans to reproduce more which would then pass on the genes etc. etc. etc. | 82463674-70a2-4905-996d-ccbf3f8d638d |
cfsdu4 | Why have supersonic flights such as the Concorde been abolished completely? | Supersonic flight atill happens regularly. The concorde was the only commercial supersonic aircraft in use, and it was not a moneymaker. That huge accident made them retire the plane, and commercial supersonic service went with it. | ef4105d3-bab9-4cdc-8e67-6a3a7c663ee7 |
cfsdvd | Why a car’s usage is measured in distance (mi/km) but boats are measured in hours? | Boats encounter a different kind of resistance in travel. It can not be measured the same way as something with wheels. | 1d07c0df-c484-4332-ad26-e17ffa605a91 |
cfsezk | How does the 5th amendment work and why is it not taken as an automatic admission of guilt? | You are innocent until **proven** guilty.
Thats pretty important. They have to prove that you're guilty. You can't be forced to implicate yourself, the government needs to actually prove their case.
It also prevents a situation where you may be forced or compelled by some reason to confess to a crime you did not commit. If you can take the fifth, you always have the right to not confess and even just having that ability should limit someone trying to force you to take blame for not committing a crime.
One of the ideas the founding fathers had was that they would rather make guilty men go free than an innocent man go to jail. While the fifth circles around this issue without directly hitting it, you can see the ideas that to be guilty of a crime it absolutely needs to be proven, not just said. | 7586665f-04ae-4308-8548-5755b447c440 |
cfsisu | Why do cucumbers taste so mild while you're eating them, but taste so strongly when you burp afterward? | It's the cucurbitacin in them. It's a chemical that they have to help prevent certain animals from eating them (too much and there wouldn't be any to make more-hey nature!)
It's mostly in the stem end so if you don't eat that part it will cut down on it too. Also can deseed them and they will help prevent excess gas from coming up. Also the "American" slicing cucumbers have more in it and the Asian/English types have less. | 0e5c4d88-9603-4dc8-af4d-7abc0fa70454 |
cfsr1d | why are women not prone to baldness? | Actually baldness is carried on the X chromosome by the female, but she is usually protected from baldness, whereas guy do not have another X to counteract it's effect.
On the aetiology side of things, it's to do with too high testosterone levels that again girls don't have. | 95ba85f4-57a2-4153-a84a-7a9a91ba4b5a |
cfswnm | Why does the taste of something change with the temperature? | Taste is its own sense, but a good portion of how we taste food is by the way it smells.
So think of heat as movement. Something hot has molecules that are moving all over the place (think steam). Something cold has slower moving molecules (think ice).
The faster moving molecule means there’s more of them free floating around the food, producing a stronger smell. That hot plate of fresh spaghetti seems to be more flavorful, because it’s literally throwing its smell molecules (which I’ve just now dubbed smellecules™️) at your face as you chomp down on it. Whereas the day-old fridged spaghetti has fewer smellecules™️, so it ends up tasting like sadness. | 872495ed-c13e-469c-a274-3036815b1b5c |
cft8dm | Why do many insects under complete metamorphosis? Isn't it a huge waste of energy, not to mention leaving it extremely vulnerable? | The energy is worth it if it allows the animal to change its environment to better suit the goals of the different life stages.
For example: the goal of a caterpillar is to eat and grow. That's it. Crawling around is just fine. It doesn't need to be flashy and brightly colored. It can stay camouflaged among the vegetation, or build up poisonous chemicals within itself, or grow unwieldy but dangerous spikes to ward of predators. The only places it needs to get to are new food sources, but that's fine because they're going to be in places where food is plentiful.
On the other hand, the butterfly needs to find a mate - preferably one that is as unrelated to itself as possible. It might need to be very brightly colorful so to attract the attention of potential mates. That will also attract the attention of predators, so it needs to find mates *quickly*. Flying is a great way to get away from its cousins and siblings and find a mate quickly. Flying also means that it can move away from an area that doesn't have food (you know, since it ate all the food as a caterpillar).
Similarly, cicadas can live happily underground, unnoticed and inaccessible to most predators. They have access to food and shelter, and don't need to travel far. But at some point, they need to reproduce and finding a mate underground is difficult when they're all trying to be unnoticeable. On the other hand, being [loud AF](_URL_1_) attracts a lot of attention. So some cicadas evolved the strategy of *everyone bones at the same time* so predators are [so overwhelmed with cicadas](_URL_2_) that they can't possibly eat them all.
So the two different life stages are designed to do two things. Even animals like us mammals do similar things: children go through a "metamorphosis" of sorts during puberty. As children we're really only meant to do two things: figure ourselves out enough to function, and get big. Once we've had time to do that, we hit puberty and change so that we can get busy makin' babies. It's certainly not as drastic as the changes that many insects go through, the idea is the same.
EDIT: That is to say, from our human perspective it seems like the adult form is the important part, since we spend so much time in it. For many other animals, it's still the "most important" part because it's when genes get spread, which is kind of the point of living, but for many animals it's the shortest part of their life. They do most of their living in an early but perfectly functional life stage and the adult stage exists solely to make a baby. For some animals this is so intense they [don't have mouths as adults](_URL_0_), because they are never meant to live long enough as an adult that having a mouth is necessary. | 35c58261-0942-4550-b016-09daf4cc8cb2 |
cftdzd | Are you taking in fresh oxygen when you breathe in near a tree? | You are taking in oxygen wherever you breathe. There is no such thing as 'fresh oxygen'. Oxygen we breathe is simply a molecule that is produced via many natural occurrences. The tree will produce oxygen as a result of photosynthesis, but it's a very small amount compared with what aready exists in the air you're breathing. | ddd5e587-6485-45b7-9ec1-cd0b3d8fa128 |
cftk3w | Why do people catch diseases like the flu or strep throat multiple times when diseases like measles are very difficult to catch after you have already gotten it once? | The flu and strep are very broad categories. Many diseases are called "the flu" and new ones form every day, so your body can fend off any you've already had but there are so many out there that you still end up catching a different strain later. | 09816de0-9459-44a2-9363-0be8c8a89f90 |
cftpdd | why do some stars look brighter when you are looking away from them than when looking directly at them? | you eye has two different kinds of sensors. One senses light (on or off, called a rod) and the other senses colors, called cones. The cones are concentrated around the center of the back of your eye so the main focus of your sight has good colors, and the "edges" have better black and white sensitivity. So when you look just to the left or right of a star, it seems brighter. | 8dca71e5-5224-44b8-80cc-d16255410941 |
cftsdf | why did light skin appear in Europeans and not in native North Americans? And how long did the process take? | There is evidence that humans expanded to Europe as much as 150,000 years ago. Being so far north they would have less sunlight to worry about and would have adapted with lighter skin pigmentation.
Whereas humans expanded to north America only 20000 years ago by crossing the land bridge from Russia to Alaska. So they have had significantly less time to adapt to the conditions.
Native Americans also expanded from eastern Asian ancestors whereas Europeans expanded from western Asian/African ancestors. So there would have already been a big difference between the two populations. | 77bd3fa1-87d4-4c63-b420-37b939e70095 |
cftz9c | Sauna Heat | Adding to what other commenters said, going outside exposes you to much more radiant heat, in addition to the convective heat in a normal steam sauna with a more traditional heating element.
You used the example of going outside when it is 105 and it being hotter than a sauna at 105. These are not equivalent. A better equivalence would be sitting in 105 degree shade compared to sitting in a sauna. In sunlight, the radiation from the sun is heating the surface of your skin, plus the convective heating of the air outside, versus just the convection heating of the hot air in the sauna. | 3731d0c1-d338-4876-92ed-9c76d7bf8483 |
cfu3ab | Why can some plants grow roots from a cutting, yet Florist flowers cannot? | Florist flowers do not grow roots after being bought because of two things. First, and most commonly, they are not fresh. They have probably sat for weeks in fertilizer infused water, which makes them look and smell fresh, but kills the buds of the roots IIRC. If you bought them specifically fresh, and they don't sprout roots, it is either that they are annual, or have been cut too high in order to fit into a shallow vase. | 91e82c0e-b29f-41e5-9795-2e31c8edf33d |
cfubt7 | Why do drops of liquid still stick to a container if the liquid is poured out? | It's not surface tension, it's adhesion. Water has the quality of adhesion that causes it to stick to things other than itself, as well as cohesion which causes it to stick to itself as seen in surface tension. Simply put, water is sticky. | 5a0e4ff6-373e-41a8-a105-b701065d0a75 |
cfuniv | Why do candles slowly disappear on a candle warmer? They aren't burning. | Candles burn by first melting wax, sucking it up the wick, then boiling it and burning the vapor. Candle warmers only do the melting part, and the wax slowly evaporates just like liquid water would when left out. | 6f4e86c1-210b-4604-b8f2-7d4d1ae22652 |
cfuon1 | How do paintings get their value? For instance a Picasso painting may be worth 1M. How is artwork value measured? | It’s demand. If enough of the right people want it, it’s priceless. If no one wants it, it’s worthless | 79a19351-6a11-4a15-a329-0173e6f803d4 |
cfvnfc | How can the same meteor showers occur every year and not run out of meteors falling to earth or other passing planets? | So there is a lot of debris in space. We are not running out of it any time soon. Comets leave a lot of debris when they orbit as well.
_URL_1_
This website gives a good visualization of that.
Also don't forget about all the junk we put up there.
_URL_0_ | 484eec88-89f6-4e88-a9d8-b9a8d79c0f9e |
cfvpmt | what's the meaning and difference between "Workforce Participation rate" and "Unemployment rate"? | Unemployment only counts people who are actively trying and failing to find a job.
Workforce participation includes people who have chosen not to work for whatever reason (they are already rich, they are a stay at home spouse, they are disabled, retired, etc.) | c1990eb9-1500-4df9-a54f-e0204ca86f02 |
cfvr0z | what is meant by streamlining governance? For example if we say there is a need to streamline corporate governance, what would it entail? | If you have a business that has a management structure that looks like this.
1 CEO
5 Regional managers
30 Area managers
300 Local Managers
300 Assistant Local managers
And you cut the amount of managers down by keeping the most capable. Getting them to do more, making the the less capable redundant you could end up with a structure like this.
1 CEO
2 Regional managers
10 Area Managers
100 Local Managers
300 Assistant Local managers
You can maintain good control, save on millions in salaries and have each remaining manager more directly answerable. | f102deb6-63a6-4a41-bbc1-dd0494a3dce4 |
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