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489
6mqbwz
Physics
how does having two eyes increase our depth perception? My depth perception seems the same whether I'm looking out of one eye or two.
So, having two eyes allows you to [triangulate]( URL_0 ) distance. Knowing the distance between your eyes and the angle to the object you're looking at from each eye, simple trigonometry allows you to calculate the distance. Your subconscious does this automatically. Your brain also uses other cues to judge distance: h...
2
kytl8u
Other
Why are there different variants of sign language? Couldn't one form become universal and be understood by all people regardless of language?
I was told of this but in Australia the deaf use Auslan. And a woman went into the local school for the deaf and asked if they had an American exchange teacher working with them. They said yes why. Apparently a bus load of small children past her signing out the song Twinkle twinkle little vagina. LOL. Apparently the s...
8
696bf7
Other
Why is it preferable to have illegally obtained evidence thrown out of court as opposed to keeping it and prosecuting the one who obtained it?
If the evidence was obtained illegally, there's good cause to suspect that it's been tampered with otherwise, or processed incorrectly, or perhaps not even valid evidence to the crime in the first place. Another way to look at it is that if the officer was willing to break the law to get the evidence, who's to say they...
20
6bb21w
Physics
Where do I end, and where does my bed begin? If I'm laying here... at a molecular level is there a clean divide or a gradient area where I'm part mattress?
I get that things never "touch" due to electron clouds, molecular bonds and all that jazz, but is that gap measureable? Can we see it with a powerful enough microscope? Id love to see the gap between 2 metal plates, sorta touching, but not really. If you take two hunks of large nucleus atom, or a large molecule, and pu...
6
9fq77u
Technology
Why do submarines have to surface at all? Can't they just operate underwater for the entire length of the mission, especially if they are nuclear-powered? I have heard that diesel engines cannot remain submerged for a long time, so they have to surface very frequently. But what is it they actually do by surfacing? Also...
Former Submariner here, and theoretically, without getting into too many details, they can. Technically the only thing that would keep them from staying at sea, submerged indefinitely is the amount of food they can carry to feed the crew.
24
5oumxi
Other
The French Foreign Legion and the Siege of Jadotville I just recently finished watching The Siege of Jadotville. I found the context interesting and wanted to do research on the actual events and story. I came cross a man named Roger (René) Faulques whom fought AGAINST the UN and Irish soldiers as a mercenary. Now I le...
So, let me begin by dispelling the common notion that UN resolutions carry some sort of weight of law. They do not. There is no law in international politics. Countries can and frequently do ignore UN resolutions when they feel those resolutions are in the slightest bit inconvenient. Rather than viewing a UN resolution...
1
62st77
Engineering
Why can't magnets create perpetual motion?
The first two laws of thermodynamics; 1) Energy cannot be created or destroyed in an isolated system. 2) Entropy of any isolated system always increases. Magnets can not add energy to the movement for they have no energy of there own that is coming in. They are a constant force. In this system the friction of the pendu...
9
9ffe02
Physics
Why do hurricanes hit the U.S. East Coast so often but never on the West Coast?
Hurricanes do hit the western US, its just happens significantly less. At least once every 2 or 3 years the remnants of a hurricane will pass through Arizona.
17
b8lvyr
Engineering
How does a helicopter pilot bail out if he is going down? Clearly they can’t use an ejector
Helicopters can autorotate, which means they use the big propeller on top to slow themselves down and land somewhat safely. To do that, they switch the way the blades are facing so the air going by as they fall makes the blade rotate, then switch them back to make them lift the helicopter. Some military helicopters, th...
8
768uzt
Biology
how can you get a bruise or a cut and not notice or feel it until you either use hand sanitizer or someone notices and tells you
Your skin has specific types of nerve cells to signal different sensations to your nervous system. For instance, when you put pressure onto your skin, that activates pressure sensitive nerves, which send the signal to your brain, and you feel pressure there. Likewise, there are specific nerve cells that signal pain, ca...
1
geia33
Economics
Keynesian economic theory Could someone explain it to me? I tried reading about it from various sources, but I'm not sure if I completely understand it. I need to be able to explain the theory in high school. Thanks in advance!
For high school level-economics, calculating a country's gross domestic product is usually done with this simple formula: GDP = C + I + G + (X – M) GDP = private consumption + gross investment + government investment + government spending + (exports – imports). In periods of economic downturn, private consumption and g...
4
l7ckr5
Economics
Stock Market Megathread There's a lot going on in the stock market this week and both ELI5 and Reddit in general are inundated with questions about it. This is an opportunity to ask for explanations for concepts related to the stock market. All other questions related to the stock market will be removed and users direc...
Ok, so they burrow the stock and sell it. But from whom do they borrow and where do they pay interest?
489
o0evad
Economics
Why have most prices been continuously increasing for several decades but wages haven’t been at the same rate?
Rich people used their money to bribe politicians into changing the rules so they could keep and make more money. Then they did it again. And again. Then they used that money to buy all the major media everythings and used THAT power to convince all the poor and middle class people to fight each other for the scraps le...
5
87s46l
Technology
How does CGI “age?” If something looked real “at the time” why does it look less real now?
Something other people haven't addressed is increased resolution; CGI made for a standard definition release looks garbage on a HD monitor, it's the same for HD to 4K too.
29
6f40be
Mathematics
Why does e (the number) come up in so many seemingly random applications?
It comes up a lot because it is a function whose derivative is proportional to its current value. Many differential equations that describe natural phenomena show this kind of dependence, making (e) inevitably show up in the solutions describing these natural phenomena. Another way to think of it is in terms of the Eul...
5
6wlo6e
Biology
Why do we feel the compulsion to do something physical (punch/scream/kick) when we get angry?
When you get angry you get stressed. When you get stressed your body reacts by releasing chemicals like adrenaline. It's like a fight or flight response, if fear is flight then anger is fight. All of the energy produced by these things has to go somewhere and you get the urge to do SOMETHING and due to the stimuli that...
1
did0zd
Mathematics
What makes "Median" a relevant metric?
Usually it's when you are concerned with distributions. In the case of median income, you'd rank everyone's income, and pick the person exactly halfway down the list from biggest to smallest incomes. Same with houses, if you made a list of houses from most expensive to least expensive, it would be the one halfway down ...
4
8ubaen
Technology
Why does having WiFi turned on improve location accuracy on iPhones?
WiFi access points help to triangulate the position of a device whose WiFi is turned on. Thus, all a phone needs to do is detect various WiFi hotspots in its range, and then its location accuracy improves, because the geographical location of millions of WiFi access points can be obtained from a centralized database
3
8psefh
Biology
If your muscles produce water as a waste product from burning glucose, why do you also need to drink water?
You lose water through other routes, whether its through sweating, or breathing out (condensation through your breath) or pee. The amount that your body generates through using glucose isn't enough to sustain you. Generally, you need to pee a certain amount out every day to get rid of the bad stuff that's in your body....
1
bv01bd
Biology
What happens to the body/brain when people faint at the sight of blood?
You get spooked and your arteries and veins dilate. Your heart can't keep the blood pressure up, so the blood pools in your legs and your blood pressure drops. So the blood can't get to your brain. This causes you to faint. It's called a [vasovagal response]( URL_0 ). And that's why sitting down and squatting will prev...
1
hny7vp
Other
- How does someone like Dominic Cummings achieve the level of influence his position in government affords him?
Dominic Cummings' political reputation comes from two main sources: campaigning and being a special advisor. His most prominent campaigning role was with the Vote Leave campaign. Obviously this campaign was successful, which is a strong point in his favour. The campaign also used quite distinctive tactics, such as a lo...
1
bldp09
Biology
what are prion diseases? Are they like other diseases or are they completely different?
Bacterial diseases are caused by bacteria, viral diseases are caused by viruses and prion diseases are caused by prions. Prions are proteins that can have two states (or more) one that is harmless, and one that is harmful. And unfortunately a prion in the harmful state, can cause other prions in the harmless state to s...
2
jp2x3k
Physics
What would you hear if you were travelling at the speed of sound towards/away from something making noise? What would you hear if you spoke?
If you're inside a cockpit you will hear yourself speak normally because the air in the cockpit travels with you. If you're not in a cockpit, well you won't hear anything beside the roaring of air ripping your skin off, but if you don't take that into account you'll still hear your voice because the sound propagates th...
3
nb3pjz
Engineering
Even if pipeline computers are hacked, can’t the valves be opened and closed manually to keep fuel flowing?
The pipeline operational controls weren't hacked, it was all of the ancillary systems. Customer management, orders, logistics, etc. The pipeline was shut down because they couldn't track who was buying what from where and for what price.
2
euz060
Other
Are there notes in-between the half steps of a piano? I'm sure this has been asked before, but I couldn't find anything online. Are there notes in-between the piano keys? And if so, why are they never used? Do they sound terrible? I'd love it if someone could clear it up. Thanks!
Charles Ives made quarter note pianos with the "notes" in between the usual keys. It's pretty interesting stuff! URL_0 The video features a video of said piano
6
6lmy1l
Economics
Could someone explain me why such thing as toll roads exist ?
[here's a video]( URL_0 ) of a toll road made by a private citizen to go around a damaged section of road. Before the toll road, the detour was 14miles. In the video the guy explains he had the road built by a construction company on credit - his house is the security in case the toll charges don't cover the costs. Ext...
4
fw6i0g
Chemistry
How does rocket fuel ignite and burn in space in the absence of oxygen?
An ordinary fireworks rocket would work just fine in space, its black powder propellant has its own oxidizer built in.
4
ggpjtl
Chemistry
What is the convention for naming new drugs? I mean they have all these weird unpronounceable names so they have to give them different names. What is the story on that?
The brand name is whatever the marketing department of the company comes up with. The generic names have some general guidelines to follow (like certain types of antiviral drugs ending in -vir, monoclonal antibodies end in -mab). Generally, the rest of the generic name is some sort of reference to a certain part of the...
1
8mdw4u
Culture
Amish are famous for barn-raising, but how often do they actually need to raise one?
Not often, it's just an interesting sight to see a hundred men build a barn in a day instead of the usual three men taking thirty days. Since they're not paying for the labor, they can pull of the brute force build that a typical construction firm cant.
3
8ti2ej
Engineering
Why do wine bottles have that huge indent at the bottom?
They're called 'punts' and are tradition at this point. Back in the era of glassblowing every bottle by hand, punts were the last section of the bottle to be formed.
2
nyg31l
Chemistry
How can edible things have zero calories? For example: mustard.
There is also the fact that if it is less than 5/calories per serving, they are allowed to round down to zero. This is why some packages that have both per serving and per container facts on it may say 0 calories per serving but 15 calories per box.
5
dwlfa5
Biology
If identical twins share the same DNA, why do their fingerprints differ?
Genes are more like a recipe than a blueprint. Two muffins from the same batch will look different close up.
3
gz5idy
Engineering
Why do ships have circular windows instead of square ones?
A circle has infinite points, a rectangle has 4. Less points = more stress. Hull warping and twisting = stress. Stress will find the easiest outlet to relieve itself.
15
f8gy46
Biology
How can Type 1 diabetes have any hereditary components if having it was a death sentence over 100 ago? Wouldn't all genetic traces of it had been destroyed prior to the 20th century?
Because people carrying it had complications or died from it AFTER they conceived children.
5
n4wljd
Biology
How is an animal or human able to sense where on its body something is touching its skin? I know there are topographical 'maps'in their brains, but how does this translate to an individual knowing where on its body the touch is being applied?
The individual touch-sensitive nerves all over your skin are connected to that "map" in your brain. Your brain knows "when this nerve lights up, that's my left index finger" (or whatever) because it's got a continuous nerve connection all the way out to that physical location. Areas with high nerve density (fingertips,...
1
9ukkxp
Chemistry
Can someone really O.D. from potassium, and if so, how much would someone have to have to cause negative side effects?
The LD50 (the dose that'll kill 50% of people) for potassium is 2.5 grams per kilogram of body weight. For a 80kg person, that is 200 grams. A banana contains around 0.8 grams of potassium. If a 80kg person were to eat 250 bananas, they'd have a 50% chance of dying. However, the body naturally excretes potassium. Assum...
1
dn1jgz
Biology
Why is it harder to swallow a pill or tablet than a piece of food the same size or bigger
Speech pathologist here (we treat dysphagia, or swallowing disorders, in addition to communication disorders). Taking pills is more difficult because the liquid we often take pills with moves much more quickly than the solid consistency of the pill. Therefore, we’ve already swallowed the liquid (or lubrication we’re us...
9
jjgfbo
Biology
What is a panic attack. Like what causes and what is happening during it
They're awful. You literally believe with every ounce of logic that you're actually dying. You literally couldn't be more afraid. It's your bodies "fight or fight" response turned up to 11. What triggers them varies. I get them from disappointing figures of authority in my life, like my employer or someone I really res...
5
g2274s
Biology
What do the “absolute threshold for touch” mean? I saw in another ELI5 comment thread that the absolute threshold for touch is a bee’s wing dropping onto a person’s cheek from one centimeter away. What does this mean and how did they determine it? Edit: does*
I believe that is the lightest sensation that can be perceived by our nervous system. How they figured it....I hope not through trial and....error.
1
71wzo4
Engineering
What is the science behind ICBMs?
The B stands for Ballistic, which means that the missile is boosted by rockets to a high altitude, then falls back down unpowered at an extremely high speed - something like 7 km (4.3 miles) per *second*. The sheer speed, combined with the lack of flames out the back, makes an ICBM extremely hard to track and intercept...
1
b9fpau
Technology
How do images get printed on cakes or beer foam?
Same with home inkjet printer. Just that the ink that's used is edible ink. Tiny nozzles spray high pressurized ink onto a print media, in this case a cake or coffee foam
1
a6acj0
Culture
Why is KFC a christmas thing over in Japan?
KFC put a lot into marketing. Christmas in Japan is a fun, commercial holiday. Closer to valentine's in its seen more as an adult and romantic holiday then religious or for kids. The marketing worked, they offered much higher quality meals on top of the normal stuff, and so people liked it and it became a thing.
6
9q5c3f
Technology
Why do some songs sound much louder/crisper than others on some music streaming services?
Before streaming services, music was mostly heard on the radio and on media like vinyl records, cassette tapes, and compact discs. Part of the process of producing music is a phase called "mastering" where the recorded songs are tweaked to sound the best on whatever format they are being sold in. So a version of a song...
1
7414mj
Biology
Voices usually sound tired early in the morning. What's the best way to "wake up" our voices quickly?
So I'm not sure there is a scientific way, but I'd say practice makes perfect, i tended to be late for things from time to time and get calls like "where are you, are you still in bed?" Kind of stuff. So before you answer the phone, Start off with a low growl and then raise it till you have kind of a shout. This should...
2
7ddqq1
Biology
why do scuba divers need to continually breath out when the take the regulator out of their moths but free divers do not When I was taking my diver training (I’m extremely new to this) my instructor told us that if for whatever reason you need to take the regulator out of your mouth you should exhale slowly. If this is...
Free divers have lungs full of surface air -- almost empty at depth as it compresses. Scuba divers have lungs full of compressed air -- several lungs' worth as it expands to surface pressure.
3
j0zo39
Chemistry
Why does MSG have such a bad reputation?
Alternative bonus answer: because the Knicks haven't been good for a while and the owner is a bad man. Edit: I used "bad man" because every other descriptor I thought of was not appropriate for a 5 year old.
11
8w1ti8
Technology
what is MIDI and how is it used?
[Wikipedia article]( URL_0 ). It's a set of standards (computer software, cables / connectors, etc.) for connecting musical instruments to a computer, in order to record or create music. You always have the option of using a microphone next to an acoustic instrument to record it, but this would result in recording the ...
2
6bl3op
Culture
What prevents someone from creating their own religion that practices drug use, and then doing those drugs in accordance with the First Amendment (Freedom of Religion)?
You would need to be prepared in court to prove that your religion was sincere and viable. It would be a hard and expensive fight. You would then still be liable for any drug use, or distribution, that could not be proven to be soley for ritual purposes Still, drugs would be easier to pass than say, a religion of robbe...
2
6c6xlt
Culture
What do pharmacists do besides count out pills and put them in a bottle? There's obviously way more to the job
I'm not a pharmacist, but I have worked as a pharmacy technician. Pharmacists communicate with doctors and patients to resolve issues with dosage and interactions. Techs and clerks in pharmacies are the ones who count and fill the prescriptions.
6
61ybnr
Biology
Why is the skin on our arms and legs generally clear and beautiful, while our faces and back tend to get acne and clogged pores?
Most people are kind of stating the obvious I think: your face has more/larger pores. Most of us can tell that just from looking at our arms and face. What I don't understand is why does our face have bigger pores? Is it because we need to sweat more there to keep our brain cool or something? Maybe because the sun hits...
13
il4pt7
Physics
Small dimensions? I once heard this quote on a YouTube video: "String theory suggests there's actually 11 spatial dimensions, but only 3 are big enough to notice" How can a dimension be big/small? AFAIK whenever we measure stuff (like distance/volume) it's always with respect to a (set of) dimension(s)...so this seems ...
The space doesn't have to be "flat" in a given dimension. It's actually a [major cosmological problem]( URL_0 ) whether our "normal" 3 dimensions are flat. It's theoretically possible for a dimension of space to be looped on itself, so if you travel far enough in a given direction, you'd end up where you started (like ...
2
cjovim
Economics
Why some factories runs 24/7 while others can do only dayshifts?
The cost of running a factory can be split into both fixed costs and unit costs. The fixed costs are costs of the equipment, tools, buildings and such which does not depend on how many actual units you produce. The ratio between fixed costs and unit costs varies a lot between different products. If you have more shifts...
2
gdqbrl
Technology
Why is it not recommended to have 2 antivirus programs running at the same time?
The same reason you don't have 2 chauffeurs. They fight over the wheel and eventually your car is gonna hit something.
6
a4ftky
Mathematics
is there a mathematical theory that explains/predicts ‘good’ music?
There’s a mathematical analysis by Dimitri Tymoczko that investigates cross-cultural similarities in tonal music.
22
d6fn2e
Technology
How can two videos of the same length and the same resoklution have different sizes?
Different encoding or compression protocols. Video isn't stored as raw data - those files would be massive for even short videos. Instead, the videos are encoded into different formats, which eliminate much of the raw data to reduce file size with differing effects of overall quality. Different protocols focus on diffe...
2
k4oub9
Technology
Why does a cracked TV screen show a whole bunch of colors while a cracked phone screen does not?
My phone screens have done that when they break. There are two layers though, a layer of just glass and a layer of actual screen underneath, or digitizer or something. If you only break the top glass it just looks like a crack, but if you break the underneath, it gets all colorful. I imagine it’s the touch screen aspec...
1
646hai
Other
Where did the "S" rating originate and why is it better than "A+"? I've searched on google to no avail.
In Solo & Ensamble an S ranking means Superior and is the highest achievable, or near perfect.
27
lyex9p
Technology
How do those walk-through scanners in libraries know if you're taking a book without borrowing it, especially if those books don't have metal inserts or anything like that? How does the library borrowing system work? and how come even if there is no obvious metal insert in the book those gates still know when and when ...
The most well-known anti-theft device for books is a tape of magnetic metal strip. The tapes are applied between the spine and the binding of a book (for hard covers) or deep inside in between some pages (for paperbacks). It's called **tattle-tape**.
11
l3k8r2
Chemistry
Why use wax paper to line a cake pan? It seems the wax would heat up in the oven and mix with the cake batter.
You do not use wax paper in baking. You use parchment paper. Wax paper is a divider for use in freezing things. It is not for open use.
4
ljnrc1
Mathematics
what is mathematics? I take no credit for this question - saw a thread on Twitter that started with the question: If a child asked you, “what is mathematics?”, how would you answer? Just thought it was such an interesting discussion that it would be great to ask here!
My view: Mathematics is about trying to find out what unexpected consequences a set of rules has. The best way is probably to contrast this to some things. If we compare to other sciences like chemistry or biology, they are trying to find the rules based on which our world works. No-one knows the rules in full, which m...
2
6xuejm
Other
Why does nobody play man to man defense in soccer? Watching soccer I notice nobody defends in a tight man to man defense (think basketball or ultimate Frisbee). I can see why man to man may not work with a slower team but you would think that with a very quick/physically gifted team man to man would put a lot of pressu...
For all the reasons everyone else has stated, but also due to the offside rule. If a defence was to play tight man-to-man, an intelligent attacking side could simply have one forward push his defender to the by-line (end of the field) and therefore open up the entire rest of the pitch for other attackers to exploit. Al...
5
72lpg5
Technology
why do touch screens fuck up in the rain?
They sense the presence of something touching the front of the screen that effects electric charge. The tip of your finger does this, but so do raindrops.
4
dy7zxy
Biology
How did people get enough food in pre-historic times I know that we've cultivated fruits, veg and berries to grow bigger and more nutritious over time, but how did people survive with so much more exertion and less beneficial foods.
Weren't as many people in pre-historic times so there wasn't as many mouths to feed. A forest could sustain a small tribe. Plus, they were nomadic and hunted for food.
3
c1jls2
Technology
How can apple trademark "apple"
Trademarks only apply within a specific industry or product type. They can trademark "apple" as a name for computer equipment because no one else was using it for that. They can't control its use for fruit, flavors or other unrelated stuff.
2
o2wngy
Technology
What do people mean when they say you don't actually own the games you buy digitally? I guess this comes under both technology and economics. But yeah I don't get it. You pay money for a game, you now own that game. That's how a transaction works. If I don't own it what on earth did I pay all that money for? How can co...
No, that's not how transactions work. For example, you pay to see a movie, you don't own that movie. You've paid for the right to see it once. You walk into an apartment and pay the landlord for an apartment, you don't own the apartment, you're renting it. It used to be you could go to the game store, buy the game and ...
6
gsza50
Physics
Why do dimpled golf balls go farther than smooth? I remember hearing that golf balls used to be smooth and people would actually play with old beat up balls because they would fly further than the new smooth ones. Why is this? What makes dimpled balls go further?
The dimples on a golf ball produce little pockets of turbulent air. These pockets of turbulent swirling air vortexes produce a boundary layer of air surrounding the ball that is _super smooth_ and slippery and this allows the ball+pockets+boundary layer to slip through the air. Boundary layers are fascinating stuff. Th...
2
5lf0p0
Culture
What was Nietzche's philosophy, exactly? I am at a loss as to what they mean. I'm having a hard time understanding concepts such as "God is Dead" or "Ubermensch" and only have a vague interpretation as to what they are. Any help will be gladly received so thank you in advance.
Nietzsche's "Ubermensch" is the goal that society should set for itself in the process of rejecting the morality of religion, particularly the Christian/Catholic Church. Nietzsche saw the Church's influence and power over society as the sick man's victory over the healthy man, as a real perversion, etc. In short, he wa...
11
6fqh4z
Biology
Why is it that every day at 2ish I hit a wall and feel so tired I could fall asleep in a trash compactor, but in 20 minutes I'm fine?
Do you drink coffee or take anything caffeinated in the morning? The same tiredness hits me as my morning coffee (8am) wears off around 2pm.
13
7kpmv2
Other
What's the difference between an anti-hero and a villain?
An antihero is a person who the audience or reader is supposed to identify with or support as a protagonist, but who doesn't have typical heroic qualities. Usually they're either doing the right thing for the wrong reasons or they're doing bad things for the greater good, whereas a typical hero is just doing the right ...
3
j4h1a3
Other
why can’t we domesticate all animals?
Saw a TV program on this issue some time ago. Turns out that for a certain especies to be domesticated it has to meet a few requirements. 1) They have to tolerate humans. If they are too stressed by our presence to carry out a normal life (feeding, mating, etc.) they are of no use. This should cover deer. 2) They need ...
14
6i97fi
Culture
Why are most songs that come out 3-4 minutes long?
Song length has changed over the years. I am not sure why but for some song contests (like the Eurovision song contest) every song must be of a certain length with very little wriggle room. This graph shows how song length has changed with time: URL_0
4
f4zrmw
Biology
What is the biological purpose of crying when you’re sad? Is there a purpose?
Someone has already mentioned the small dose palliatives in tears, but that’s only part of the answer. Crying comes before language, and is a way for infants to communicate that they need something.
6
78pnzo
Chemistry
Why do they say that the kitchen sink has more bacteria than your toilet?
Because ["The meat industry sued the federal government, winning the right to sell food known to be contaminated with food-poisoning bacteria."]( URL_1 ) edit: Why the down vote? Studies find more fecal bacteria in kitchens than in bathrooms precisely because our retail meat contains so much fecal bacteria: [Consumer r...
3
mydw4b
Physics
Would the Earth's rotation slow down if we got everyone on the planet to run to the east at the same time?
On a technical level yes the rotation of the earth would change but the amount would be so small as to be undetectable.
4
c1wkbe
Physics
How does “heat lightning” work? Why doesn’t it make thunder?
It does. You're just not close enough to hear it. "Heat lightning" is regular lightning seen from a distance, several miles away. You can still see the flash, but the sound dissipates before it gets to you.
3
6ez3ds
Biology
why do gamers especially find themselves staying up well into the early hours of the morning? I have played games for many years and I find that each time a holiday roles around i will get up in the afternoon and play games up until about 3-4am. Why is this. For my friends it is the same and even though during the day ...
I stay up anyway, (6PM-6AM shifts at work), and even on my days off, I keep to my work schedule; there's nothing to go out and do at 3AM, so games filled the gap :)
5
965lzf
Repost
Double Slit Experiment. I have a question about the double slit experiment, but I need to relay my current understanding of it first before I ask. ___ So here is my understanding of the double slit experiment: 1) Fire a "quantumn" particle, such as an electron, through a double slit. 2) Expect it to act like a particle...
Typically a photon is used rather than an electron, since that makes figuring out the wavelength (which determines the pattern) a lot easier, but otherwise you got it right. As far as why it works that way, we have no idea. Well, we have lots of ideas, but no solid answers. We do know that if you split a photon into tw...
11
a2e421
Technology
Why are electric cars more eco-friendly if electricity is still fossil-fuel powered? If a normal car burns gas, I get why that's bad for the environment, and an electric car doesn't. But doesn't the power that charges electric cars still come from power plants that also are bad for the environment? How big is the diffe...
Generally, electric cars use energy more efficiently than petrol cars. Also, coal and natural gas power plants usually implement expensive processes that clean up the by-products of burning fossil fuels before releasing the exhaust into the air. Petrol cars would be far too expensive if similar measures were implemente...
5
6audcf
Other
Why do we tend to view mammals and furry/soft animals, even predators, with a positive physical connotation (cute, pretty, regal, etc) but scaly animals, insects, arachnids etc are viewed with a negative physical connotation (gross, ugly, fearful)?
Not really even sure how to flair this because I don't know if it's biologically driven, culturally influenced, etc.
5
dbv6ui
Other
(At least in English) Why when followed by certain words (specifically I've noticed with anything that starts with "you") do words ending in "t" often end up sounding like "tch". For example; "I love that about you." often ends up sounding like "I love that aboutch you."?
It's the t to the y. Make a 't' noise in your mouth, your tongue is loosely at the roof of your mouth. Now make a 'y' noise; your tongue is on your front teeth. Now make a 'ch' noise, your tongue is midway between the two; as you transition from a 't' to a 'y' your tongue goes into the position to make a 'ch' and if yo...
5
7lai2x
Biology
Ketosis how does eating high fat diet make the body burn your own fat? i want to believe, but it's confusing..
Getting into ketosis isn't necessarily the addition of fats, but the lack of glucose. When glucose enters the body, it is stored as fat. With the lack of it, the body burns the fat your body has stored instead of glucose. Also, keep in mind, all fats aren't bad like everyone makes them out to be. Monounsaturated Fat an...
1
8cg0tb
Economics
In 1918, a $100 bill was worth about $1700 in today's dollars. What was the point of having such a large denomination bill?
Funnily enough, we actually did used to have thousand and 5 thousand dollar bills, back during the same time period. I imagine that they were primarily used internally in banks.
5