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|---|---|---|---|---|---|---|---|---|---|---|
5w46jc
|
Why is running on a treadmill easier than running in the street?
|
Physics
|
explainlikeimfive
|
[
"de74smk"
] |
[
"For one, there is no air resistance when running on a treadmill. When running outside, your body has to physically push the air you move through out of the way. It may not seem like much, but try running outside with a tailwind (or conversely into a headwind) and you quickly notice the difference air can make."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
n3ttrd
|
How did people start using currency?
|
I know that there are many other posts on this topic but all the replies are about why people made the change and not about how the change actually took place. Say I'm the ruler of a certain area, where people do different jobs and use the barter system. Since the barter system sucks, I want the people to use gold and silver as currency(gold and silver do not have any value yet). All the gold in the area is inside my treasury. Now how do I put the gold and the silver into circulation? One solution I can think of is exchanging the resources that people have for my new currency but that way I, at any given moment will have to keep either resources or currency, but in real life, both currency and resources exist in the market and the government keeps neither. Please give another solution or correct my solution in some way. P.S please point out my grammatical mistakes so that I can improve.
|
Economics
|
explainlikeimfive
|
[
"gwrrznu",
"gwrsgdz"
] |
[
"In some areas that the British tool over, they wanted people to work in the fields so they offered to pay them 10 crowns a day for work, they also imposed a hut tax of 200 crowns per month, which if it wasn't paid the hut was burnt down. So imposing a tax obligation and then paying in currency is one way it happened."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
g3rmdn
|
How can robots not beat captchas when some are as simple as clicking a button?
|
Technology
|
explainlikeimfive
|
[
"fnt12np",
"fnt0kc1"
] |
[
"The button clicking captcha is deceptively complex. It's really a masterpiece of design to be so simple for a human and yet still be effective. With the button clicking captcha you've already 90% passed the test before you ever see the button. They've looked at the various metadata that your computer sends, like what your browser is, and seen that it matches patterns associated with real people. They've seen that this is the first request from your IP address, or perhaps they check that you're logging in from an IP address that's already associated with the account you're logging into. By the time you see the button they're already pretty sure you're a human. Then you click the button, but it's not just a click. They watch your mouse motion. They check to see if the mouse jumped straight to the button and issued a click event. They check to see if the mouse moved in a perfectly straight line, or with other improbable uniformity. Ultimately the button clicking itself isn't that hard to design a robot to beat, but it would take some time. Once you perfect the button clicking robot and start using it you start failing all the checks that led to you getting the button clicking problem in the first place. Perhaps you make a simplified web browser that doesn't register properly as being Chrome/Firefox/IE/whatever. Perhaps you make too many requests in a short period. Perhaps you try too many times to log into accounts that don't actually exist. You quickly wind up flagged as probably a bot, so you get sent to the \"hard\" captcha like image labeling. Image recognition is one of those fun problems where the software to do it is increasingly well understood (it's an active area of research, but computers have been out-performing humans for several years now). The challenge in making an image labeling program is that you need a lot of human-labeled data to train it off of. It's costly and time-consuming to gather that data (which is the other service that companies like recaptcha offer—they're using your clicks to help big companies train machine learning algorithms for tasks like self driving cars). In the end the process for developing a bot to defeat captchas is straightforward enough, but the effort it would take to do so is greater than the effort it would take to just hire a bunch of people to solve the captchas for you. That's the threshold for \"good enough\" for a captcha."
] |
[
25
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
kiwrir
|
Why is autism such a broad spectrum?
|
Someone with autism who has a severe intellectual disability and is non-verbal has significantly different needs from a person who was formally labeled as having Asperger’s, so why are they considered the same disability?
|
Biology
|
explainlikeimfive
|
[
"ggt9uvc",
"ggtgpag"
] |
[
"Basically, all of the issues/symptoms that individuals on the spectrum have are related to the same groups of executive functions. Executive functions are things like self-control, short term memory, emotions, planning, etc. So you have a group of executive functions that are deficient in some way, and they all can have different levels of deficiency. Executive functions themselves are complicated things that can have huge variations in how much or how little they impact an individual. There are too many combinations of executive functions and severity to assign each a different name, especially given that the treatments are very similar for several different levels of an executive function. So, it makes the most sense to group everything under one heading \"Autism Spectrum Disorder\" and tailor treatment to that particular individual's needs. What you're really doing is just creating a label for the individual that can be used to get them the assistance they need. The assistance is going to be individualized, but the need for that assistance is global across the group."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
a953ry
|
Why is it, when you say a certain word so many times it starts to become alien and almost unfamiliar to the point where you can hardly understand it?
|
Other
|
explainlikeimfive
|
[
"ecgfrbz",
"ecgo9d7",
"ecgq0kt"
] |
[
"It's called \"semantic satiation\". The reason it happens is that the neurons of your brain that recognise the meaning of the word essentially \"tire out\" and so the word stops meaning anything until they've had time to recover. Source: URL_0"
] |
[
1428
] |
[
[
"https://en.wikipedia.org/wiki/Semantic_satiation"
],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6bsdzr
|
Why do scars and previously broken bones ache when there is a change in weather?
|
Repost
|
explainlikeimfive
|
[
"dhp6hzd",
"dhp6q8n",
"dhp6dl2"
] |
[
"Orthopaedic surgeon here... The real answer is that we have no idea. Some people will say that it has to do with pressure changes in the atmosphere and how that effects scar tissue or healing fractures. However, this doesn't pan out when you actually try to look at it. Not everyone gets this sort of pain, and even people who do get this pain don't always get it with pressure changes. Such as airplanes, traveling to the mountains, etc. It's completely unpredictable. However, it is totally a thing. It is absolutely a real phenomenon that people experience. We just have absolutely no idea as to exactly why."
] |
[
424
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
61y529
|
The concept of 'We are all made of star dust'.
|
I realise that the Sun's gravity is enough to create helium from hydrogen, causing heat and light to be released. How are the other elements created and how are we all made up of them?
|
Physics
|
explainlikeimfive
|
[
"dfi7l0i",
"dfi7yp5",
"dfi7mhl",
"dfieila",
"dfi7gej"
] |
[
"As stars die they start producing heavier and heavier elements. Then when they go supernova these elements are flung into space as dust and gas (star dust). This then coalesces to form planets, just as Earth did. You are made from matter from the earth, hence you are made of stardust."
] |
[
177
] |
[
[],
[],
[
"https://www.youtube.com/watch?v=7KYTJ8tBoZ8"
],
[],
[
"https://www.quantamagazine.org/20170323-where-did-gold-come-from-neutron-stars-or-supernovas/"
]
] |
[
"url"
] |
[
"url"
] |
6kecnx
|
How do some people simply switch off and fall right asleep where others it takes a longer time?
|
Biology
|
explainlikeimfive
|
[
"djleig3"
] |
[
"There are a lot of factors to the body falling asleep. First off its related to natural sleep patterns. If one is more of a night owl then they will have a hard trouble falling asleep at night as they naturally want to be awake at that time. The technical term for this is social jet-lag if you want to search it up. Then there is how tired a person feels. If one has been in bed all day and not been doing much activity then they won't be tiered and so wont go to sleep as fast. If one has been really active all day they will happily go to sleep on rocky ground. There is also how active one's mind is. Your brain being very active will lead to going to sleep later as you are kept awake by thoughts, your brain feels as if its solving a problem and so keeps itself awake. People who have mastered the art of clearing the mind get to sleep far quicker as the brain has nothing to solve so goes straight to sleep. There are various other things that are put of one's control entirely like the secretion of hormones and how good the body is at doing that/how sensitive the receptors are. High cortisol levels causes one not to sleep as well. However high dopamine or serotonin levels will cause one to go to sleep faster"
] |
[
15
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
641dsd
|
The role of the 72 virgins in Islam's version of Heaven.
|
Other
|
explainlikeimfive
|
[
"dfym3yc",
"dfyn9ww",
"dfz5qtj"
] |
[
"While they are commonly referred to as virgins, they are actually *houris*. Beautiful, deferential, heavenly beings that each believer receives...the more righteous the believer, the more they get. They are \"pure\" and for the exclusive use of that believer, which is why they are simplistically referred to as virgins."
] |
[
25
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5znvf0
|
Why is it that unplugging the WiFi router can fix the problem with slow internet, and what happens to cause it to becomes slower than it should be?
|
Repost
|
explainlikeimfive
|
[
"dezm22e"
] |
[
"The router has something called a translation table. It's a list of all connections currently going on. When a computer using the router wants to connect to something on the internet, the router writes it down in the translation table so that when a response arrives the router knows what to do with it and to which computer to send it. The router is supposed to know when connections end and remove them from the table, but like all programs, router software can have bugs, and sometimes those bugs cause connections to stay in the table forever. Eventually, the table fills up, and when your computer tries to make a new connection, it fails because the router has nowhere to write it down. This makes your internet work erratically, because most of the time it won't work, but sometimes some space in the table frees up and briefly you can make connections again. Restarting the router empties the table and solves the problem until it fills up again. There are some other possible reasons for this - maybe the router's software crashed, or there is a problem with the connection between it and the internet that will be solved by starting it from scratch - but I think this is the most likely, and the others are too specific to know about or explain anyway."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
iuz6re
|
Why can some birds like duck be served medium rare, but chicken can not?
|
Biology
|
explainlikeimfive
|
[
"g5o7k3z",
"g5o7k50",
"g5o7fer"
] |
[
"It comes down to microbes. On a steak, microbes only exist on the surface of the meat and not inside it (hence why ground meat needs to be cocked more. However, in chicken, there are microbes that are spread throughout the meat, not just the surface."
] |
[
6
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
c6vj2p
|
CBD full spectrum
|
Can it get you high or just relaxed?
|
Biology
|
explainlikeimfive
|
[
"esbhcew"
] |
[
"I have a feeling that there are people who can do a better job of describing it then I can but oh well, here it goes. So if you know anything about marijuana, you know about THC or tetrahydrocannabinol. It's the active ingredient that makes you high which can include sleepiness, increased appetite, visual and auditory hallucintations, nausea (in large amounts, think being \"greened out\"), and euphoria. THC is the part that contributes to weed being a psychoactive drug (just like acid and shrooms). Marijuana also has more than just THC as an active ingredient. CBD is another cannabinoid in marijuana, and it's the second active ingredient. CBD is non-intoxicating, which means that it will not give you any euphoria, alter your mind state (actively), and none of the other crazy effects that smoking marijuana does. It does however have many potential health benefits (studies being done still). These potential health benefits can include reducing anxiety, help reduce soreness, sleep, and even to help against seizures. Now for a direct answer to your question from personal experience. Currently, (as in literally while writing this) I vape CBD and I dont really actively feel anything, and that's normal. Since it's not psychoactive, it's not supposed to be felt like a high. So no, it definitely will not get you high. However that being said, my anxiety is definitely reduced a noticeable amount and my usual back pain is not as bad. I do fall asleep easier and I feel that it actively helps. Hopefully I helped answer your question TL,DR: No it will not make you high in the way you think and the relaxation is a lot more subtle than most people think."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
ia24im
|
What is entropy?
|
Physics
|
explainlikeimfive
|
[
"g1jfvfk",
"g1jw9k9"
] |
[
"Entropy is basically one of the rules of how the world works. Things are not naturally ordered and will naturally return to their disordered state given enough time. We can mix things that we find in the natural world together to make incredible things like buildings or planes, but given a long enough amount of time, all of those things will wear away and become disorganised. Think of it like your house. Unless you actively go out of your way to clean it, it probably tends towards getting messy. Things get spilled, or left out or dusty. The universe is just like that, given time, things that are purposely ordered will stop being ordered, as disorder is natural."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
7cfa0q
|
Why do images burn in to tv screens when you leave them there for too long?
|
Technology
|
explainlikeimfive
|
[
"dppf32z"
] |
[
"That used to be the case with CRT (cathod ray tube) displays on older TVs. Here each pixel was generated by beaming it onto the screen, and leaving the same image for too long would literally burn the screen. Nowadays with LED technologies this is no longer a problem."
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
jfb37f
|
How does investing work, and what reasons would you have to encourage more people to do it?
|
Economics
|
explainlikeimfive
|
[
"g9j5ggm"
] |
[
"You basically put money into investment goods. You buy parts of a company, or so called derivates, that are for example options to buy something later. The reason why so many people try to encourage it has 3 aspects. First the platforms make money by taking fees. Then other traders enjoy inexperienced competition they can draw money from, and third companies like investments because it helps them expand."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6hu0cz
|
Since a national government can implement a socialist program only national, isn't all socialism national socialism?
|
Other
|
explainlikeimfive
|
[
"dj1a4t0"
] |
[
"National Socialism - as in the context of Nazi Germany - was just a name. North Korea is officially called the Democratic People's Republic of Korea - and it certainly isn't democratic or a people's republic. Whilst semantically you may be correct, in reality you cannot say the words 'national socialism' without it automatically having connotations of Nazism"
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
b1edmr
|
How do scientists aboard the ISS ensure no water ingress on electrical equipment?
|
As the title suggests, I just watched this video [ URL_0 ]( URL_1 ) & #x200B; And I was curious as to what precautions were taken for the blobs of water that would break away and I can assume would hit the walls of the room they're in. I know they're only small blobs, but I've seen videos with Mr Hadfield and larger volumes of water (wet towels, how they wash etc.) and I wondered if they coat the walls with absorbent material or anything like that.
|
Engineering
|
explainlikeimfive
|
[
"eil1877",
"eil84j3"
] |
[
"They do try to seal up electrical components. Not only from water ingress but also dust. However it is not a much bigger issue on ISS then on Earth and a lot of the equipment they have is regular off the shelf components that you likely have at home. They do have a ventilation system that they have turned on quite high and most of the water droplets and dust tends to float towards the ventilation ducts. They can regulate the humidity quite accurately and will set it comfortably low to make the water evaporate quickly."
] |
[
43
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
ewu8h0
|
A mongooses immunity to cobra venom
|
Biology
|
explainlikeimfive
|
[
"fg4gvn2"
] |
[
"Your nerves are covered in protein receptors that function like little locks. They also produce proteins, called neurotransmitters, that function like little keys which perfectly match the keyhole that the receptors have. When the correct neurotransmitter goes into a receptor, it \"twists\" and briefly causes a small hole to open up in the cell. This hole allows a small amount of electrolyte into the cell, which causes the cell to briefly turn on. To prevent the cell from staying on perpetually, it has enzymes that break neurotransmitters down shortly after they enter a receptor. This causes the hole to close so electrolytes stops flowing in. The cell, meanwhile, is constantly pumping electrolytes out. Now that electrolytes can't flow in, electrolyte levels in the cell go back to normal and it turns off. Cobra venom contains a protein that fits into the \"lock\" on one of the important protein receptors on animal nerves. However, despite fitting the lock, the cobra venom protein doesn't twist so no hole gets opened and the nerve doesn't activate. The cobra venom protein is also different enough from the normal neurotransmitter that the nerve cell can't break it down. This means that the cobra venom protein just sits in the protein receptor without doing anything - blocking it from being used by neurotransmitters. If enough of this protein gets into an animal's body, it blocks all of that animal's neurotransmitters. When all of an animal's neurotransmitters are blocked, its nervous system turns off. When an animal's nervous system turns off, it stops breathing and dies. Mongooses are immune to cobra venom because they have protein receptors with a very slightly different keyhole shape than other animals. That keyhole is still similar enough that the mongoose's neurotransmitters can fit in it to function normally. However, its also different enough that cobra venom now just slightly doesn't fit. Because the cobra venom can't get into the mongoose's protein receptors, it doesn't have an effect on the mongoose."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
7al6co
|
Noise Isolating headphones vs Noise Cancelling
|
I see lots of headphones that are Noise Cancelling or Noise Isolating. What's the difference and how do they work?
|
Technology
|
explainlikeimfive
|
[
"dpatihz",
"dpatawl",
"dpbamu8",
"dpawtiz",
"dpaxxtu",
"dpaxh8r",
"dpbb8f0",
"dpbhjr2",
"dpbopww"
] |
[
"noise isolating. consider this ear plugs that have earbuds in them. THey block outside noise by providing a noise reducing barrier. In fact my isolation earbuds are so good I use them as Earplugs when using a circular saw or mowing the lawn. NO music and not even plugged in. Noise Cancelling Headphones that essentially listen to ambient noise and produce an opposite sound wave to blank out the unwanted sound. Fill your bathtub with water. Drop two rocks into the tub one at each end. When the waves collide you will see a spot where the water seems calm because the waves are cancelling each other out. Noise cancelling headphones produce this negative wave by listening in to the outside noise and producing the opposite wave to cancel out the wave just like in the water."
] |
[
8230
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
9to53h
|
How can I calculate the number of unemployed people, given the "unemployment rate" and number of employable people?
|
Economics
|
explainlikeimfive
|
[
"e8xsfse"
] |
[
"Are you assuming every one is adult and working age? What about retired people and kids?"
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
69z1hf
|
why does the beer have bubbles coming from the bottom of the glass?
|
Chemistry
|
explainlikeimfive
|
[
"dhaevbw"
] |
[
"Bubbles need a small pit or imperfection in the surface of the glass to form. Even a speck of dust or fiber in the bottom of the glass can be a place for bubbles to start. Champagne glasses are often scored in the bottom so that the bubbles want to form there. The bottom of the beer glass is probably more likely to have such an imperfection."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
7kowjb
|
Now that it’s back in season, where’s the flu been?
|
How do viruses just appear again?
|
Biology
|
explainlikeimfive
|
[
"drg0w0l",
"drg0q7e",
"drgbjc6",
"drg0shx",
"drg6elb",
"drg9fo6"
] |
[
"There are many different explanation as to why there's a flu season (a surge in influenza cases around a certain time of year), such as: * People spending more time indoors, and subsequently in closer proximity to one another. * Less exposure to ultraviolet light that could damage/destroy the influenza virus before it can infect someone. * Cold temperatures drying up mucous membranes (reduces body's effectiveness against respiratory viruses) * Cold temperatures preserve the virus longer on surfaces people come in contact with. * Less Vitamin D production in the body leading to a reduced immune system. Research in Guinea Pigs has shown that the virus is more efficiently transmitted in cold, dry air than in warm/humid air, and that it has a casing that hardens in colder temperatures (the casing typically melts in your lungs, but obviously it is degraded in higher temperatures, too). Also, there's no hard start date for the \"flu season\", it's just a general term to describe the time frame in which doctors and scientists observe an uptick in flu activity. It's not attached to any set calendar date."
] |
[
149
] |
[
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
8239n0
|
Why does it hurt to pee with an erection?
|
Biology
|
explainlikeimfive
|
[
"dv77y6j",
"dv758rd"
] |
[
"Uh, it does? Last time I did it it wasn't uncomfortable. I always sit down in that case though, maybe that's why."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
jkndft
|
If I bought a brand new laptop and didn’t use it at all, how many years later would I still be able to plug it in and have it work? What causes laptops to degrade in just a few years as we use them?
|
Technology
|
explainlikeimfive
|
[
"gak2sz2",
"gak24r2",
"gak39oz",
"gak9vx0",
"gakarx9",
"gakmbfw",
"galom72",
"gakarg8",
"gakatpy",
"gakdjjp"
] |
[
"I have a 2009 asus laptop that still works, can still run team fortress 2 and counter strike. Only the battery stopped working. Just wanted to pump up asus"
] |
[
46
] |
[
[],
[],
[],
[],
[],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
gmqb37
|
How does the body become heavier when you exercise for the first time in a while when you should be losing weight?
|
Biology
|
explainlikeimfive
|
[
"fr52589",
"fr58chi"
] |
[
"It's pretty much a collection of some water weight that then gets shed. You still will lose weight as you lose fat content, but for the process of muscle usage to occur, water is needed for those chemical processes. Glycogen fuels the body during exercise, and needs water to bind with and generate energy for muscle use."
] |
[
18
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
lci6lj
|
Why do we crave sweets after a meal?
|
Biology
|
explainlikeimfive
|
[
"gm0dekb",
"gm10f0s"
] |
[
"Sugar cravings that strike after a meal may be due to serotonin, a feel-good brain chemical that's associated with an elevated mood. Eating a sugary dessert causes serotonin levels to rise in the brain, which can make you feel calmer and happier."
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
bux9zb
|
How did the United States become a world powerhouse in such a short time?
|
Other
|
explainlikeimfive
|
[
"epix343"
] |
[
"Back to back world wars is the short answer. The major world powers before WW1 were the British Empire, France, the German Empire, and Russia. All of those nations were heavily impacted by both world wars. The USA was in a fine position, especially after WW2, to essentially take over from all of those countries just by virtue of having a lot more money to spend, and suffering a lot less damage."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
lg1ipq
|
what happens when inflation gets so large that even for the strongest currency, a loaf of bread costs 100s of whatever?
|
Economics
|
explainlikeimfive
|
[
"gmot8mg",
"gmotouw",
"gmou93z",
"gmowheg"
] |
[
"People start burning the cash or finding other practical uses for it because the paper it is made of is worth more than its face value. Also the economy typically collapses and you see a lot of barter."
] |
[
9
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
bkljzz
|
What makes it impossible for us to reach the core of the Earth in any way and how are do we know whats underneath us, if were unable to get even remotly close to it?
|
Physics
|
explainlikeimfive
|
[
"emhkdss",
"emhktrf",
"emhs922",
"emhixob"
] |
[
"It’s impossible for us to reach the core of the Earth because we don’t have the engineering capability to tunnel into places at such high pressures and temperatures. The temperature will melt any equipment we use and the pressure will close any gap that we make. Mines in the crust require various methods of support and bracing to keep the cavity open and they are still dangerous places to due to mine collapses. To give you a sense of scale of the Earth, the apple analogy is a fairly good one. If the Earth was the size of an apple, the crust would be approximate to the skin of the apple in terms of its thickness. Now that you can picture this, know that we have never tunnelled beyond the crust. All of the coal and minerals and precious metals we have ever mined have been from the crust. The deepest hole we have ever drilled when the Russians were specifically trying to reach the mantle was a little over 12 km deep (the Kola-Superdeep borehole), and they had to give up due to temperatures overheating the drilling equipment. At this spot in the continental crust, it was about halfway to the mantle. Below the crust there is still **another 2850 km or so** of mantle before you reach the outer core. This is all solid rock, though the mantle behaves more like an extremely viscous plastic-y solid, so would likely be much more challenging to drill through even if we overcame the temperature issue. Even invisaging fantastical future technologies, it is *extremely* unlikely that we will ever drill anywhere near the Earth’s core."
] |
[
31
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6l3vvr
|
How are Cities created/made
|
I was talking to a friend about building new houses in the UK, and we asked ourselves how are Cities made? Is it just a collection of buildings which become a city. Or are they planned and set out. And If so, how do they get there name and layout? For example, I think Milton Keynes is the newest city in the UK. But how was it made and how did it get where it is and layed out like it did?
|
Engineering
|
explainlikeimfive
|
[
"djqzqzp",
"djr4qis",
"djr5927"
] |
[
"Well, it's interesting that you ask that from the UK. Historically, most cities arose as a result of humans wanting to live in a location that provided some economic advantage. Examples include a crossroads on trading routes, port cities, and areas with some natural resource to be exploited. Many of these cities grew up organically based on function and common modes of travel at the time. With European colonialism, cities were 'founded' in the New World and elsewhere. These communities were often planned by a royal governor and laid out according to the best practice of the time. When the Spanish settled the Americas, for example, the [Law of the Indies]( URL_0 ) established rules for where cities should be built and how they should be laid out. In the same vein, various US cities were planned and built by a single visionary 'planner'. Examples include Philadelphia (William Penn), Savannah Georgia (James Oglethorpe), and Washington DC (Pierre L'Enfant). In all of these instances, the city streets were laid out, and spaces such as parks and squares where reserved for the public. The private sector, individual homeowners and commercial developers, built the buildings along the streets according to the established plan. In 1902, a man named Ebenezer Howard proposed a new concept for creating cities: the [Garden City]( URL_1 ). The basic idea was that a city should contain all the elements that you needed, housing, industry, commercial district, etc. in a compact area that was separated by a greenbelt from the next compact community. He actually built a few of these towns in the UK: Garden City of Letchworth and Welwyn Garden. After WWII, the British government adapted this idea to deal with the crowded conditions in cities and the need for more housing, and sets out to build a series of new communities based loosely on the Garden City model. [Milton Keynes]( URL_2 ) is one of those 'New Towns' built by the government. I hope that answers your question. Some cities grow up organically because there was an advantage to settling there and others are planned and executed from a single vision."
] |
[
27
] |
[
[
"https://en.wikipedia.org/wiki/Laws_of_the_Indies",
"https://en.wikipedia.org/wiki/Garden_city_movement",
"https://en.wikipedia.org/wiki/Milton_Keynes"
],
[],
[]
] |
[
"url"
] |
[
"url"
] |
60t713
|
Why does residual coffee/tea in a cup generally only stain in a ring where the liquid meets the air? Is this some sort of reduction/oxidation product?
|
Chemistry
|
explainlikeimfive
|
[
"df948bx",
"df948e3"
] |
[
"Someone else might have a better answer, but I think the reason is simply that at the edge is the only contact point of liquid & mug where the water is evaporating, and it leaves behind a deposit of tea/coffee as it does."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
kdffqh
|
why is it that nowadays we have painters/artists that can make almost photographically real drawings but portraits from(for example)the 1600s look so strange?
|
Other
|
explainlikeimfive
|
[
"gfw799r",
"gfw7lsc",
"gfw97k2",
"gfw7ina"
] |
[
"Well, for starters nowadays people can use photographs as a reference. In the past, this was much harder. The best examples are going to be [Vermeer]( URL_0 ) you might also know this [one]( URL_2 ) I highly recommend the documentary URL_1"
] |
[
42
] |
[
[
"https://cdn.britannica.com/73/190473-050-28D1DEBA/Milkmaid-oil-canvas-Johannes-Vermeer-Rijksmuseum-Amsterdam-1660.jpg",
"https://en.wikipedia.org/wiki/Tim%27s_Vermeer",
"https://upload.wikimedia.org/wikipedia/commons/thumb/d/d7/Meisje_met_de_parel.jpg/1280px-Meisje_met_de_parel.jpg"
],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
o33xhx
|
Why is physical harm, like a slap on the back, more painful when you’re wet than when you’re dry?
|
Biology
|
explainlikeimfive
|
[
"h2ag825",
"h2a8g6d"
] |
[
"Under normal conditions, water isn't compressible, air is (this is why hydraulic tools are a thing). Also, water is denser, so it's harder to move out of the way of incoming force. These property have the effect of transmitting the force more efficiently. For a scaled up example of this principle at work, read about [Operation Crossroads]( URL_3 ). This atomic bomb test used decommissioned warships in 1945 at Bikini Atoll. Three bombs of identical yield were planned, to test ideal weapon deployment against a naval formation. The first bomb, shot Abel, was detonated 520 feet above the surface of the water. Here's footage of the [test]( URL_1 ) from the 1995 movie, '[Trinity and Beyond: The Atomic Bomb Movie]( URL_0 ). The second bomb was detonated 90 below the water, and, well... I'll let my man Bill Shatner [tell]( URL_2 ) you, he does it better than me. (Warning: Disturbing footage, live animals were used during the test). The same principle is why depth charges can sink a submarine without actually making contact with the hull of the sub. The pressure wave from the explosion is enough to crumple steel. It's also why falling from a great height into water is deadly. The water can't get out of your way fast enough, and the impact is therefore forceful enough to crush bones."
] |
[
35
] |
[
[
"https://www.imdb.com/title/tt0114728/",
"https://www.youtube.com/watch?v=KUD0l-7J4Ms",
"https://www.youtube.com/watch?v=gy6-ZKWCoH0",
"https://en.wikipedia.org/wiki/Operation_Crossroads"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
gdz9oy
|
Why do old jazz recordings sound better than other records that have been released later on?
|
It seems to me as if most jazz records of the 50's and 60's sound way better in recording quality than most of the other music at that time (e.g. blues, country, rock, etc.) or even later on. Why is that?
|
Technology
|
explainlikeimfive
|
[
"fpkns8c",
"fpkbzig",
"fpkuzyh",
"fpkq594"
] |
[
"**Why do they sound better than most of the other music at that time?** Jazz music, including its crooner singers and big bands, was some of the most popular mainstream music at the time. As a result, they had more budget and resources for good recordings. **Why do old jazz recordings still sound better than newer music?** From a music perspective, many of the musicians who were playing on the jazz records of the 50s and 60s were seasoned live performers and session musicians. The way records were recorded back then involved the whole band to be in the same space performing the music. As a result, a lot of these musicians had lots of experience and good chemistry with each other, which meant they could groove better and bounce off each other musically. In later times, as studio technology evolved there was less of an emphasis of capturing the perfect recording of the performance in the room, as session musicians could be swapped in and out and record on completely different days, multiple performances could be cut together and edited to fix mistakes, etc. Some people would regard say that as a result, some of the soul and imperfection was removed in favour of higher fidelity and perfect performances. Speaking of music technology, the actual equipment was very different in the 50s and 60s. Because they couldn't record lots of microphones at once, often bands would have to perform around one or two microphones and members would have to physically move back and forth in the room to adjust their volume. This made the sound of the room a very important basis of the sound. Modern recording methods favour multiple microphones allowing for the complete isolation of each member of the band, meaning that only the pure instrument is captured, allowing for greater fidelity, but without the character of the shared sonic space being in the record."
] |
[
27
] |
[
[],
[],
[
"https://youtu.be/lz3WR-F_pnM"
],
[]
] |
[
"url"
] |
[
"url"
] |
ifmk1p
|
Can someone explain the concept of Dissociative Identity Disorder to me?
|
Biology
|
explainlikeimfive
|
[
"g2ogfbh"
] |
[
"Basically, you psychologically distance yourself (dissociation), often via memory loss, from your identity to the point that your identity seems like an entirely different person to you. You fill in the blanks of your memory and personality with other aspects of your memory and personality to create a new identity. Both (it can be more than 2) identities persist and you switch between them. It's often triggered by severe trauma. Dissociation often features a detachment from reality as well, so often times people with DID also fabricate aspects of their personality, which is how they can have multiple personalities."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
gwxois
|
How come during a frightening incident, everything seems to go in slow motion?
|
Biology
|
explainlikeimfive
|
[
"fsxu6un"
] |
[
"Mainly adrenaline Your body surges with adrenaline which has a lot of effects on the body. Your muscles are able to oxygenate better, your heart rate increases. Your lungs ability to transfer oxygen to blood increases. Your nerves relay information more efficiently (not faster, but less important functions are downgraded... like feeling a feather across your skin is given lower priority to sensing danger) All those effects lead to your brain prioritizing information differently. You aren't really faster in any substantial way but you prioritize fight or flight responses above non essential things which devotes more brain power to the thing frightening you making it seem like you sense it slower. It's more of a hyper awareness then a speed thing"
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
fs3po8
|
Why is a greenscreen green?
|
Technology
|
explainlikeimfive
|
[
"flz9k22"
] |
[
"Cameras have red, green and blue sensors and you get the sharpest image out from a color that just stimulates one color. You could use any color to do what has the general name chroma keying but red, green or blue has the best result Human skin color contains a lot of red so it is not used with humans subjects but can be used for other stuff. That leave blue and green and both common to use. On the reason that you see green more then blue is that is an uncommon color in our clothes but blue is common. Another is that because human vision is most sensitive to green light because we have evolved in areas with lots of green plants that we needed to distinguish. So most cameras have 2 green sensors for each red and blue and the result is that green results in the sharpest edges."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
8gzr88
|
What happens with the senses of a person who is hallucinating? Do they get "overwritten" by the brain or do they actually report erroneously?
|
Biology
|
explainlikeimfive
|
[
"dyg0kmz",
"dyfy861"
] |
[
"We are pretty much hallucinating all the time. What you see and hear is highly processed, your brain is filling in a lot of blanks, using memory and deduction. When someone you know is in your peripheral vision, you brains \"sees\" details your eyes do not. When you are listening to your favorite song in your car, you will still \"hear\" lyrics muffled by noisy traffic. Your brain is good like that. When mental illness or drugs make you hallucinate, that part of your brain gets out of control. In much the same way you can see a bunny rabbit in a cloud, your brain seizes on the wrong details, applies the wrong memories and makes the wrong deductions, and you are seeing things that really aren't there. In addition, there is a part of your brain that tests reality. If you see someone and your brain registers them as having three arms, that part says \"wait a minute, that can't be right, we need to take a closer look\", so you do, and realize it is two people standing at a weird angle. It is the same part of your brain that gets suppressed when you dream, that's why just accept being an adult in elementary school or having to leave work to go pitch for the Yankees, without looking at it more closely. The mental illnesses and drugs that cause hallucinations are doing the same thing."
] |
[
86
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
jzf6qr
|
Why do 18 year olds in photos from 100 years ago look like the 30 year olds in photos today?
|
Biology
|
explainlikeimfive
|
[
"gdbj7f6",
"gdbiqx7",
"gdbj42l"
] |
[
"I think it's probably something to do with hair and clothing styling, preferred body-shape of the time. Watching Karate Kid from the 80s (about 40 years ago) with Elizabeth Shue and my kids were saying she was dressed and styled like a grandmother also she had a much more \"solid\" body-shape. She was the \"hot girl\" at the time. Afterwards, watching Cobra Kai, the modern girls' styling is completely different (hair and clothes) and they have the super slim body-shape of (general) preference today. 100 years ago there was no teenage fashion - just clothes for kids or clothes for adults - it's hard to look young when your wearing old lady clothes. I guess it's similar with boys/men."
] |
[
15
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
gkidof
|
Observable Universe means that there's is a universe we cant observe. Why is that and is there a way to observe it someday?
|
Other
|
explainlikeimfive
|
[
"fqrluuy"
] |
[
"The observable universe is the part of the universe we can see. It is a sphere with a diameter of 93 billion light years. The unobservable universe is the space outside this sphere which we can't see and never will be able to see. This is because any object farther away from us than light could travel in the age of the universe will never reach Earth. There isn't a way to see past it."
] |
[
8
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
i2vfch
|
How does automatic Hover Mode in Helicopters detect wether you are flying or standing still relative to the ground beneath you?
|
Technology
|
explainlikeimfive
|
[
"g07zkz8",
"g093m2x"
] |
[
"The Tello has vertical computer-vision sensors; it remembers what it looked like 'before' and if the image is offset it knows how to move it back into alignment. It works best when there is some high-contrast item within view -- if it is over a flat matte surface it doesn't work well. & #x200B; Which as I say that sounds quite a bit like the homing sensors of a missile; my how technology has advanced."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
iuh3oj
|
why do we see those colorful (red,blue green) spots in our eyes after looking into the flash from camera?
|
Biology
|
explainlikeimfive
|
[
"g5kqiua"
] |
[
"From what I know about how the retina (optical sensor of the eye), it will mildly desensitized after staring at a bright light source. Now because camera flash is usually very bright (compared to background light level) and flashing at a very short amount of time the effect of desensitization is very pronounced, resulting in the complimentary color spot In your vision. Now what I meant about complimentary color is the inverse of the color your eyes are exposed to (e.g. a bright flash in warm tone may result in a bluish spot). You can also experience this effect by staring at a bright screen/lamp and then suddenly close your eyes. You'll see a sort of shadow image when your eyes are closed."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
i7m9qh
|
How do aimbots in first person shooter video games work?
|
Technology
|
explainlikeimfive
|
[
"g12tnt1"
] |
[
"The most rudimentary bots take a screenshot, process the pixels and look for a cluster which looks very much like what the bot has been told 'an enemy head' should looks like. They aren't accurate, but they are almost impossible to detect by anti-cheat software. The bot works completely outside the confines of the video game boundaries. Then you have aim bots which work based on the aiming system. In a lot of games, you have what's called a \"hit scan\" system. The software knows where the enemy is on your screen. The software knows where your crosshair is pointing. When you press the trigger, the software checks if you are pointing at \"an enemy\". Since the software knows where \"an enemy is\", the aim bot can dig up this information from the computer memory. It can then convert it to X,Y coordinates on your screen and snap your crosshair to it. This is easier to detect by anti-cheat systems because the game's memory will show as being accessed by foreign software."
] |
[
14
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
88gq81
|
Why are AR-15’s so controversial while many other semi-automatic rifles and handguns with lower round capacities have almost identical lethality capabilities if multiple magazines are utilized that only take a second or so to swap out?
|
Other
|
explainlikeimfive
|
[
"dwkhryu",
"dwkhrr1"
] |
[
"It's not so much that the other guns are considered ok, but AR-15's are just well known, so they're kind of the poster boy. Like, if you asked someone what a semi-automatic was, the first thing that pops into their head is an AR-15. It's an extremely popular gun, both in sales and pop culture. It's also been used in a lot of the recent mass shootings (7 out of 10, according to [source]( URL_0 ) ). It's basically become a symbol. The same way when you say \"soda\", odds are the first thing most people think of is Coca Cola. Some regions in the US literally refer to sodas/pop as \"coke\" regardless of what kind of soda it actually is. Tissue = Kleenex, Teflon, Oreo's, Nike's, Dorito's, those are all examples where a specific brand became synonymous with the actual product. (and hell, stuff like AK47's/Kalishnikov's as well)"
] |
[
9
] |
[
[
"https://www.seattletimes.com/nation-world/latest-mass-shootings-all-have-ar-15-in-common/"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
8vggxr
|
Where goes my sixpack in the evening
|
I'm into sports and healthy nutrition. My bodyfat is low enough to have a defined sixpack in the morning. But I noticed, that in the evening I kind of bloat up, skinfold increases and sixpack is still visible but a lot less than in the morning hours. Am I adding fat during the day and loose it during the night?
|
Biology
|
explainlikeimfive
|
[
"e1n7ujk",
"e1n7whz"
] |
[
"> Am I adding fat during the day and loose it during the night? You are dehydrating during the night and rehydrating during the day. Bodybuilders when preparing for their shows will avoid drinking anything so their skin is tighter to their muscles. It is perfectly normal and not really something you should try to stop."
] |
[
15
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
o6g3v4
|
- How do you contain the heat of a fusion fuel generator that reportedly reaches a temperature of 100 Million Degrees Celsius
|
Physics
|
explainlikeimfive
|
[
"h2s7ih6",
"h2s83oi"
] |
[
"There are two main things at play, 1. The density of the material at that heat is very low 2. You don't let it touch the container Most fusion experiments involve somehow confining the plasma so it can't touch the container walls, while this plasma is very hot the heat transfer to the container is relatively slow as there is effectively a vacuum between them. There are a few ways to confine the plasma, for example you can use a magnetic field because the plasma is made up of charged particles. Also this plasma isn't very dense, the pressure inside of these reactors is typically even less than atmospheric pressure. While it may be very hot there just isn't that much material to heat up the container."
] |
[
14
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
a5nc0o
|
Why does razor with several blade feels better than the one with only one blade ?
|
Physics
|
explainlikeimfive
|
[
"ebnytls"
] |
[
"Imagine standing on top of a nail. Ouch, that's no fun! All of your weight is pressing down on that single nail, so it's definitely going into your foot. You can kind of reverse the forces so instead of thinking your ~140 pounds is pushing down on a nail, it's one nail pushing against your foot with ~140 pounds. Now imagine instead laying your entire body across a densely packed bed of nails. Instead of a single nail pushing with your whole body weight, it's more like maybe 140 nails pushing with a pound each. Still ouch, probably but not as much. Or 280 nails pushing with half a pound each. Or 1000 nails pushing with 14 hundredths of a pound each. The more nails you have, the less pressure you put on any single nail. Similarly, the more blades you have on a razor, the less the pressure is on any individual blade. Alternatively, your blade could be longer, but since your body is curved a long blade will lose contact eventually so...yeah more blades that are reasonably sized. You also get smoother cutting because the blades can get progressively closer to your skin and trim the hair down instead of trying to cut the whole thing at once. On the other hand, more blades is more expensive and, like a ridiculously long blade, a fat razor with too many short blades just doesn't give you enough of a noticeable difference to be worth it. Which is why companies usually stop at 5, *maybe* six if they're feeling like they can market them, and why your bargain razors are going to be 2-3. EDIT: Some words"
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
g4cnai
|
I keep seeing posts, “I pointed my telescope here for 20 hours to give you this image.” Why does it have to be 20 hours of pointing? What’s happening exactly?
|
Technology
|
explainlikeimfive
|
[
"fnwpwtq",
"fnxcv9p"
] |
[
"Simple version, there are 2 kinds of light a telescope camera gets: signal, and noise. Signal is what you want; it is light that came from the object itself. Noise is what you don't want; light from the atmosphere, from interstellar dust, cosmic rays hitting the detector, etc. What you can see in a picture depends on how these two things compare: this is usually called the \"signal-to-noise ratio\", or SNR. A high SNR means that you can see a lot of detail, while a low SNR may even mean that you can't see the thing at all. A high SNR is like listening to a flute play in a silent concert hall. A low SNR is like listening to a flute play on the side of a busy highway. When a chunk of light hits the detector, it doesn't know which it is, which means that it can't really figure out which is which. There is, however, one difference between the two that we can use: Signal increases with time, noise increases as the square root of time. For example: imagine you have two identical telescopes pointed at the same object. Telescope A spends 1 minute pointed at that object, telescope B spends 4 minutes pointed at that object. Telescope B will have four times as much signal, but only twice as much noise. This means that as you spend more time pointing at a single target, the SNR increases, which lets you see more and better detail."
] |
[
48
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
atsssf
|
Why does it take so long for mood stabilizing drugs such as antidepressants to work?
|
Biology
|
explainlikeimfive
|
[
"eh3eutj",
"eh41ci1",
"eh3cq9a",
"eh3at9w",
"eh3smfk"
] |
[
"In the case of antidepressants, it's because their mechanism of action is neurogenesis in the hippocampus. This process takes roughly two weeks to have an effect on serotonin levels. The fact that antidepressants act via hippocampal neurogenesis is relatively recently discovered by science - within about the last ten years."
] |
[
74
] |
[
[],
[],
[],
[],
[
"https://en.wikipedia.org/wiki/Antipsychotic"
]
] |
[
"url"
] |
[
"url"
] |
|
jv74g5
|
How does the body decide when to wake up?
|
Biology
|
explainlikeimfive
|
[
"gchtsuj",
"gci5tlt",
"gci1k5k"
] |
[
"Depending on how tired you were/your conditions. Like if you're on fire you'll probably wake up"
] |
[
4
] |
[
[],
[
"https://www.sleepcycle.com/sleep-science/the-stages-of-sleep/"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
ij8jgi
|
How could ancient civilizations carve so finely inside volcanic rocks, granite or other type of tough rock?
|
Engineering
|
explainlikeimfive
|
[
"g3bx2ul",
"g3bwgd8"
] |
[
"Volcanic rock is generally tough, but iron chisels can dent it, or granite at least. You only need to cut it deep enough that you can insert wooden wedges into it. Then you soak those wedges in water so they expand, and the expansion of enough wedges causes the rock to crack. You can't carve granite until you have invented iron though, cos bronze tools are quite soft."
] |
[
8
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
8kay1d
|
With all the advances in computing, why are email servers still so limited on file attachemnt size?
|
Technology
|
explainlikeimfive
|
[
"dz68q5x",
"dz6s20l"
] |
[
"They're not. Your service provider or company imposes it's own limitations to conserve network bandwidth."
] |
[
17
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
mlj27p
|
How does something wind up becoming muscle memory after some time?
|
Biology
|
explainlikeimfive
|
[
"gtlplle"
] |
[
"There is a specific part of your brain (cerebellum) that does that specifically so you can take your higher mind off doing those things."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
dats8k
|
how do arm prosthetics work especially when you have almost your whole arm gone?
|
Technology
|
explainlikeimfive
|
[
"f1vezn8"
] |
[
"Sensors are placed to pick up signals both electronically and physically from remaining muscle structures left around the stump These are used to actuate the various artificial muscles of the prosthetic either through mechanical action or electronic/pneumatic actuators"
] |
[
14
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
80bt31
|
If heat rises, why do lakes and other bodies of water freeze on the top first?
|
Physics
|
explainlikeimfive
|
[
"duufero",
"duufojw"
] |
[
"Due to the black magic of water molecule structure, it's at its **most dense** around 4'C and **less dense** at 0'C. This means between 0 and 4'C the coldest water _rises_ and freezes at the surface. If it weren't for this one innocuous quirk life probably would not have evolved past the simple pond life stage as lakes would always freeze solid. As it is you get the frozen top and the fluid bottom."
] |
[
23
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5pkgcf
|
Why does an avalanche occur in snow but not in sand?
|
Chemistry
|
explainlikeimfive
|
[
"dcruxir",
"dcrx269"
] |
[
"One major reason is that snow falls from the sky, and can build up to a point where it's unstable. But sand is deposited by blowing wind, the force of which keeps sand dunes from building up too high, rather than just dropping out of the sky."
] |
[
3
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
h7bkef
|
Elementary Particles
|
Physics
|
explainlikeimfive
|
[
"ftrjhpw",
"ftrkxu3"
] |
[
"Bosons vs Fermions: Bosons are force carrier particles and can \"stack\" ontop of one another. You can have two or more of them in the exact same place at the exact same time. The most familiar of these is the Photon. Gluons are also bosons. Fermions are what we consider to be standard mass particles like quarks and electrons. These follow the Pauli Exclusion Principle in that they cannot stack ontop of one another. Quarks vs Leptons Quarks are what compose protons and neutrons, which themselves compose the nucleus of an atom. Quarks are fundamental particles in that we cannot seem to find anything that composes quarks. They just exist. They are very small. They posses fractional charges. There are two basic types - Up and Down, each of which have two heavy \"cousins\", however those versions are rare and unstable. Leptons are electrons, neutrinos, and their heavy cousins. Electrons have negative charge, their charge is stronger than quarks. Neutrinos are insanely small, barely interact with matter, and their existence is basically an accounting trick when turning neutrons into protons and electrons, or turning protons and electrons into neutrons. The Leptons are both fundamental particles as well. For a bit of a dive into what they are all made of, they are made of \"energy\" in different forms. We understand the workings of physics under the quantum field theory model, which suggests that there exist across all of space and time these fields, and particles are excitations in these fields. When we say a particle is fundamental, we are saying that there exists a field for that particular particle. There is an electron field, and all electrons are excitations in the electron field. Same with all the bosons and all of the fermions."
] |
[
6
] |
[
[],
[
"https://en.wikipedia.org/wiki/Standard_Model"
]
] |
[
"url"
] |
[
"url"
] |
|
fd2z0p
|
How the f*** are gameshows funded???
|
Economics
|
explainlikeimfive
|
[
"fjeo8qh",
"fjeo5rn",
"fjerde1",
"fjeogwg"
] |
[
"Same way all TV show are funded - ads. Game shows are actually some of the cheapest TV to produce. Aside from the host, who probably makes good money, there are no other highly paid people working on the show. The prizes may _seem_ large, but are nothing compared to the salaries of some actors; you can give away $30k all day long and never come close to the millions it costs to pay high profile sitcom actors _per episode_."
] |
[
11
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
9l80g7
|
What are the effects of THC being stored in fat cells for a long time?
|
Biology
|
explainlikeimfive
|
[
"e74qthy",
"e75dkq1",
"e757dlu"
] |
[
"You can fail a screening test for THC is you haven't used in a while but your body recently used the fat in those fat cells for energy, releasing the THC into your blood. You're not likely to notice, making the test result disappointing."
] |
[
21
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
931inx
|
Is there a reason cows have to be milked so goddamn early in the morning? Will their utters explode if they’re not?
|
Biology
|
explainlikeimfive
|
[
"e3a0xqa"
] |
[
"When the udders are full and not emptied, it triggers a release of a hormone that slows/stops the production of milk. A calf would naturally feed several times during the day, milking simulates that. Just like with humans, a woman who stops breast feeding or pumping regularly will stop lactating"
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
g0pgaf
|
How was experimental CGI rendered before the mid-eighties?
|
I've always been fascinated with computers from long before my time. 1980s CG animation in particular is something I've always found oddly soothing. But a lot puzzles me about how it worked. How were things like [Carla's Island]( URL_0 ) made as early as 1981? If I were working as an animator at the time, what kind of program would I have used to create things like that? Weren't computers at the time only capable of simple pixel images at most?
|
Technology
|
explainlikeimfive
|
[
"fnax9fl",
"fnaxyp0"
] |
[
"Those images were animated one frame at a time in a supercomputer at LLNL. Computers in 1980's were capable of working in 3D, just not in real time (I was at SIGGraph in 1980). Essentially you figured out each voxel (3D pixel) and color coded it. Then you rendered the 3D space to 2D with a camera algorithm. You printed the 2D image on a piece of paper and photographed it, or if you had one, directly to film. Then you developed the film and projected it. What's most \"breakthrough\" about Carla was that the water has a surface normal. This means that the moonlight can reflect off it based on the relative height of the water in two voxels. That's why the second half of the film is so dark, to show off the awesomeness of that algorithm."
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
a46tv5
|
How do Draw Bridges kmow when a boat is coming to pass by? How are the traffic lights programmed for this?
|
Technology
|
explainlikeimfive
|
[
"ebbzelf",
"ebc40uy"
] |
[
"Usually there's someone controlling the drawbridge, and when they open the bridge the lights turn red"
] |
[
10
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
awzffs
|
Why are some roads paved with asphalt and why are some roads paved with concrete?
|
Can some one explain the reasoning behind why some roads are laid with asphalt vs some being done with concrete? I know there is a difference in cost but are there any reasons besides that?
|
Engineering
|
explainlikeimfive
|
[
"ehq7gnt",
"ehqfbrx",
"ehq7ufa"
] |
[
"concrete is more durable, but it is also more expensive. asphalt costs less, but is less durable"
] |
[
52
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
kcur9m
|
why do game or website servers have to go down for maintenance? What’s being done during these times and why does it require them going offline?
|
Technology
|
explainlikeimfive
|
[
"gfsqy7r",
"gfstkks",
"gfsqzn2",
"gfsyxe4"
] |
[
"Seen many car mechanics fixing a car that is currently running?"
] |
[
11
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6mia52
|
why is coffee called joe?
|
Repost
|
explainlikeimfive
|
[
"dk1umjx"
] |
[
"There are two strong ideas but neither is verifiable. 1. A corruption of one of the slang words for coffee; **jamoke** (a compression of java and mocha). So **\"cup of jamoke\"** transitioned its way to \"cup of Joe\" or \"cuppa-Joe\". 2. *Joe* is jargon for \"fellow, guy, chap\" and so \"cup of joe\" means \"common man's drink\" or **\"cup of Joe's drink\"** (average Joe, etc). [Source: Snopes]( URL_0 )"
] |
[
11
] |
[
[
"http://www.snopes.com/language/eponyms/cupofjoe.asp"
]
] |
[
"url"
] |
[
"url"
] |
|
mmi223
|
Why is it that when lightning strikes land a person can still get electrocuted even after being 10+ feet away from the strike zone but when electricy hits a big body of water fish don’t float up to the surface dead?
|
Earth Science
|
explainlikeimfive
|
[
"gtrjih4"
] |
[
"Some do, but you should never be in the position to see them. Regardless, [most of the electricity is on the surface, so any fish beneath the first foot should be fine.]( URL_0 .)"
] |
[
6
] |
[
[
"https://www.weather.gov/safety/lightning-fish#:~:text=So%20why%20don't%20all,the%20surface%20and%20are%20unaffected"
]
] |
[
"url"
] |
[
"url"
] |
|
evdyfr
|
When a flying object moves from the equator due north, why does it drift east (right of intended path) as stated in the Coriolis effect?
|
Physics
|
explainlikeimfive
|
[
"ffv5kbb"
] |
[
"It is **not friction.** It is conservation of momentum. Think about the distance covered by something on the equator as the Earth rotates vs something at the rotational poles. Earth spins towards the East so as you move North there is excess momentum towards the East which translates to course drift."
] |
[
7
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
afx6h7
|
what allows warm-blooded animals to regulate their own body temperature while cold-blooded ones cannot?
|
Biology
|
explainlikeimfive
|
[
"ee1xsjc"
] |
[
"Warm-blooded animals will do things like shiver when they are cold or sweat when they are hot. This helps them maintain a constant body temperature but it also costs a lot of energy. Shivering forces your muscles to work which requires food to fuel them and sweating requires extra water. Warm-blooded animals have to eat and drink much more often than cold-blooded ones because they have to do more work to maintain their body temperature. That's why a snake can eat once every few weeks and be fine while a mammal needs to eat every day or more."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
hdnntv
|
Why/how do songs get stuck in our head? Why is it so much harder to get a song out of our heads than other thoughts?
|
Other
|
explainlikeimfive
|
[
"fvm98sj",
"fvmeu96"
] |
[
"It could be that if you cant finish the song ,your still trying to end it and cant stop until you end the song"
] |
[
5
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
5m7it9
|
What causes body aches when fighting a fever?
|
Currently ill with the flu and my whole body hurts. What causes this?
|
Biology
|
explainlikeimfive
|
[
"dc1ddaz"
] |
[
"When you have the flu, your immune system diverts the white blood cells to fight off the flu virus, thus leaving your muscles and joints feeling sore and achy. ... This causes inflammation in muscles and joints, resulting in pain in a similar way to mild arthritis or rheumatism. Copied from Google. Either way I hope you get feeling better soon and this gives you a little insight into what is happening inside your body."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
ep7try
|
How does the global average temperature cool down? For example shouldn't any given month be hotter than that month was during the previous year?
|
Physics
|
explainlikeimfive
|
[
"fehsljq"
] |
[
"The Earth emits light, particularly in the infrared spectrum. With that emitted light the Earth loses energy, and thus heat."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
k4x06a
|
why can't a hydrogen atom isotope have more than 2 neutron, or if it is possible, why is it unstable?
|
Chemistry
|
explainlikeimfive
|
[
"gebe1j5",
"gebf0o0"
] |
[
"Neutrons alone are fairly unstable, they happen to decay into protons with a half life of a few minutes. Inside an atom they tend to stabilize more. The necessity of neutrons in an atom is pretty clear, pure positive charges really do not like each other and don’t stick well to each other, but from what we see protons stabilize neutrons from decaying. This is why in atoms where there is an excess of neutrons, we typically see beta - decay that converts a neutron to a proton, similarly to how they would decay if a neutron was just alone in space What could be happening is that the neutrons are actually in a constant state of decay, neutron decay releases an electron but this electron doesn’t have enough energy to escape the nucleus because of proton attraction so it just recombines with another proton into a neutron. Too many neutrons and it can occasionally escape. The energy calculations at least support this and allows us to calculate decay for isotopes that we have not yet observed to exist."
] |
[
8
] |
[
[],
[
"https://en.wikipedia.org/wiki/Isotopes_of_hydrogen"
]
] |
[
"url"
] |
[
"url"
] |
|
ji6yr5
|
How is it that homework help websites such as Chegg and Coursehero are somehow able to remove all other answers from the internet?
|
Before these sites were around I would have no trouble googling my problem and finding help on a solution. Now, all of these answers are behind a paywall and rarely seem to be able to find anything anywhere else.
|
Other
|
explainlikeimfive
|
[
"ga4vp3f",
"ga5iq7s",
"ga5ttnv",
"ga5w40z",
"ga7e1ra",
"ga6uvrc",
"ga7fxzx",
"ga5af0d"
] |
[
"It is nearly impossible to remove something completely from the internet. Your answers are most likely still there. If they're not it could be because the hosting Website is no longer online. What's most likely happening is that pages like Chegg and Coursehero have a higher rank on the search engine and thus being displayed first. The \"old\" pages are being pushed further down as their rank isn't as high. Another explanation might be that those pages pay the search engines to get displayed on the first page (think of it like ads). Try to alter your search query in a way that it looks less like a homework related question. That increases your chances of getting to free answers. You can even try advanced search queries to exclude those homework pages from the search results."
] |
[
285
] |
[
[],
[],
[
"outline.com/"
],
[],
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
5z4n2q
|
Why do we know more about space than about our oceans?
|
Other
|
explainlikeimfive
|
[
"dev7l5g",
"dev8gnh",
"dev7kb3",
"dev7oh1"
] |
[
"I mean, that's a stylized fact. It's hard to literally write down a list of things about space and the deep sea that we know and literally compare their length. The point of it is that we can see space very easily and there are a bunch of giant light emitting structures (stars) that make it even easier. The bottom of the ocean is separated from us by miles of light absorbing water and isn't full of things that emit a ton of light to begin with, so it's tough to see. It's also only slightly less difficult to get to than space, technologically speaking, so it's not like we've had way more time to physically explore it."
] |
[
16
] |
[
[],
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6t7nn4
|
how do scat porn "performers" do what they do without throwing up on the spot or getting ill in the longer term?
|
Culture
|
explainlikeimfive
|
[
"dlij0xk",
"dliqxcq"
] |
[
"Fake pooooooo. No seriously. I read on reddit before that it's usually chocolate or something, and not actual shit."
] |
[
13
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
byprch
|
How hard would it be for the UK to just scrap its plans and stay in the EU?
|
Culture
|
explainlikeimfive
|
[
"eqk9e1m"
] |
[
"If parliament agreed to do it, it would be very simple. Straight vote, revoke article 50, cancel the process. Politically, it would be very fractious, probably political suicide for many MPs voting for it."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
jrgq6w
|
Please help me understand vector spaces and matrices
|
Hello I'm having trouble understanding the concept of vector spaces and matrices. Additionally I can't understand when the two vectors is part of the set V
|
Physics
|
explainlikeimfive
|
[
"gbt5g6m",
"gbt3wmk"
] |
[
"Let's look at a plane. The xy-plane. We are both happy with the xy-plane, because we know what (2,1) means. It means go 2 in the \"x\" direction and 1 in the \"y\" direction. The reason we are happy with this is that if we ever want to give a name to a random spot in the plane, we can always name it by saying \"start at the origin, walk in the x direction by this amount, and then walk in the y-direction by this other amount.\" But then some wild and crazy guy comes up to you and says \"what is this xy-plane nonsense? I call it the ab-plane!\" And he draws the \"a axis\" and the \"b axis\" for you. URL_0 You say, \"That's crazy nonsense, dude! What about my point (2,0)?\" And he says \"That's fine. If you go 2 in the a direction and 2 in the b direction, you end up at the same spot, so I call that point (2,2) in the ab-plane.\" After arguing for a bit, you realize that every point in the xy-plane can actually be given these crazy ab-coordinates. In fact the ab-coordinates turn out to be very useful if you want to make a hexagonal grid! Wild and crazy guy is not so crazy after all! The math behind this is: Call the vector of length one in the x direction \"x\" and the vector of length one in the y direction \"y\". These vectors x and y form a basis for the plane, but so do the vectors a and b of length one in the directions a and b. During the argument about the point (2,0), we found that the same vector could be expressed as a linear combination of x and y: 2x + 0y, or a linear combination* of a and b: 2a + 2b. The plane here was our vector space."
] |
[
8
] |
[
[
"http://i.imgur.com/JX9k1.png"
],
[
"https://www.youtube.com/playlist?list=PLZHQObOWTQDPD3MizzM2xVFitgF8hE_ab"
]
] |
[
"url"
] |
[
"url"
] |
c9ollm
|
When smoking cannabis, why do you only get high for a few hours even though THC remains in your body for 30 days?
|
Biology
|
explainlikeimfive
|
[
"et0lq5e"
] |
[
"The psychoactive effects wear off bc your brain flushes the THC. What doesn’t cross the blood brain barrier is stored in muscle and fat tissue after the body metabolizes it."
] |
[
6
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
eeece7
|
Why are human females generally smaller than males if they're the ones built for and have a wider space/hips for carrying a child?
|
Biology
|
explainlikeimfive
|
[
"fbt6wf3"
] |
[
"We likely evolved this way to support a traditional hunter gatherer lifestyle. Traditional gender roles are loosely based on how humans behaved in a hunter gatherer society. With Lions for example it's the female that does the majority of the hunting, with humans it's the opposite. Males typically were the hunters while females stayed nearer to camp to care for children. Women would forage, cook, and care for children while Men would go away from the camp to hunt. Males being larger is advantageous for hunting and chasing prey, while women being smaller conserves energy. Human children have a very long gestational period as well, so being smaller would mean having more energy available to grow a child. Despite existing for 10,000 years our society is a blink of an eye in evolutionary terms. Humans and our ancestors lived as hunter gatherers for hundreds of thousands of years because we became farmers. So evolution hasn't really had a chance to catch up yet."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
7wn314
|
Why are some genes not "activated"?
|
Many times I heard something like: humans have every gene to have feathers or chicken have genes thanks, other animals have teeth. Why we don't have feathers then and chicken doesn't have teeth? How does that work?
|
Biology
|
explainlikeimfive
|
[
"du1n1gm",
"du1p4og"
] |
[
"You have lots of genes that do lots of different things that all of your cells don't need. Your nerve cells don't need to grow hair and your eyelid cells probably shouldn't be making stomach acid. As cells become specialized, they deactivate the genes they don't need so only the proteins from the ones they do need get coded. Sometimes, over the course of evolution, a gene will get deactivated for all cells, and then it just becomes a leftover that isn't used anymore."
] |
[
10
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
li6noe
|
how does a mould (penicillium) become an antibiotic?
|
I don't exactly understand the step from the mould to the pill/medicine. I mean, you couldn't eat the mould and get the same result, or could you?
|
Biology
|
explainlikeimfive
|
[
"gn1ejv1",
"gn1emp2",
"gn1em5j"
] |
[
"Long story short, yes, you could - moldy bread has been used to combat disease for millennia. The distinction is essentially one of refinement/purification and dosage; the antibiotic is «cleaned» from other substances (such as rotten bread) and bits that might not be quite as good for you, and packed into an easier-to-swallow capsule that is less unappealing than old, moldy bread. :)"
] |
[
11
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
l8u7lg
|
- if diamonds are the hardest substance on earth, how do AND did people cut them into shapes for jewelry, especially the tiny tiny cut diamonds
|
What actually cuts the diamond, how do they make the tiny diamonds the same shape as big diamonds. How does it work if diamonds are the hardest material on earth???
|
Other
|
explainlikeimfive
|
[
"glej24r",
"glegqdr",
"gleh12m"
] |
[
"There are a couple of different methods used. Although diamonds are the hardest material on earth, they are not equally hard in all directions. The molecular structure is octahedral - think of two pyramids connected base-to-base. The molecules are tightly bound in the direction where the two pyramid bases join, but they're not as tightly bound in the planes parallel to the pyramid sides. So the first method is \"cleaving\" - you cut a shallow groove along one of those planes using a another diamond (or a diamond impregnated saw blade). You put a steel blade in that groove, whack it with a mallet, and voila - the diamond splits in two along that plane. The second method is sawing, which has two methods: you can use a diamond (or a diamond impregnated tool) to wear away material, or you can use a laser... because a diamond is just carbon, it burns quite easily, and there's no risk of shattering the stone, which can happen if you use a diamond tool (think of those cleavage planes as fault lines - the vibrations of a saw can set up an internal \"earthquake\" under the right circumstances. Up until about 40 years ago almost all diamonds were cut with diamond saws. Now they're almost all done with lasers, because it's cheaper, faster, and safer."
] |
[
12
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
bdfx9v
|
Why and how are dark bags formed around your eyes due to lack of sleep, and when rested enough, they go away?
|
Biology
|
explainlikeimfive
|
[
"eky15tq"
] |
[
"Bags under the eyes are normal fat deposits that help cushion and protect your eyes. Even if you don't have visible ones, we all have them. They can get swollen because of fluid retention (stress, hormones, age, genetics), loose skin (aging, rapid weight loss, genetics), or inflammation caused by allergies, lack of sleep, smoking, etc. Their colour is down to your blood. Part of this is genetic - the thickness of your skin there, the pattern of vascularisation, etc. Part of this could be inflammation."
] |
[
43
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
l897xs
|
What is dogecoin, for a beginner to stuff like this and willing to participate.
|
Economics
|
explainlikeimfive
|
[
"glbc8vw"
] |
[
"Doge coin is a prank. Some programmers were put off by the undefined basis of bitcoin. \"Anybody could do this\", they thought, and launched doge coin to prove their point. Now it seems that people have taken the prank seriously."
] |
[
11
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
k1q6sr
|
what happens when people stand up too quickly and their vision goes black and their body goes all jerky ?
|
Biology
|
explainlikeimfive
|
[
"gdpszp9",
"gdpskis"
] |
[
"Not sure about the jerkiness. The vision or lightheadedness is due to [Orthostatic hypotension — also called postural hypotension ]( URL_0 ) where your blood pressure drops when standing. Basically, your brain needs a bit more fresh blood than it's getting. This is similar to why fighter pilots wear g-suits (because g-strings would just hurt in this application)."
] |
[
13
] |
[
[
"https://www.mayoclinic.org/diseases-conditions/orthostatic-hypotension/symptoms-causes/syc-20352548"
],
[]
] |
[
"url"
] |
[
"url"
] |
|
a3jff0
|
The earliest sunset and latest sunrise doesn't happen on the winter solstice. Why is this?
|
Other
|
explainlikeimfive
|
[
"eb6s643"
] |
[
"How far the earth is tilted away from the sun and where the earth actually is in its orbit are two different measurements, and it's the second one that has more of an impact on when sunrise/sunset occur over the course of a year. If you took a camera and nailed it to a pole so it didn't move, and took a picture of the sun at the exact same time every day for a year, and then stitched the pictures together, you'd get something like this URL_0 It's called an *analemma* and it shows the effect of Earth's elliptical orbit. The top part of the figure-8 is when we're furthest from the sun, in May-June-July, and the bottom part is when we're closest to the sun in Nov-Dec-Jan. The two extreme points at either end are where the solstices are. It's where we're tilted the most toward/away from the sun. But as you can see, we're not yet at the top/bottom of the loops. In that winter loop on the right, the sun is furthest *right* in the analemma, but it's still got a little ways to go before it gets furthest *down*. When it hits that point, that's the latest sunrise, and it varies based on your latitude. Another way to look at it is to think of a day as the time it takes for the sun to get back to the same place in the sky. As you can see, it slips up and down, so what we'd need is for the sun to get back to the same *vertical* position. If you made your camera do that instead -- take a picture of the sun in the same place -- then the camera would be waiting more than 24 hours, or less than 24 hours, depending on where in the analemma the sun was. It's clear that there are parts of this figure-8 where the sun is crawling, and some parts where it's zipping."
] |
[
72
] |
[
[
"https://telescoper.files.wordpress.com/2016/12/maxresdefault.jpg"
]
] |
[
"url"
] |
[
"url"
] |
|
848n8s
|
Why do aeroplanes/airplanes have headlights?
|
Engineering
|
explainlikeimfive
|
[
"dvnmjc7",
"dvnmmde",
"dvnr8j8"
] |
[
"> Why do aeroplanes/airplanes have headlights? Aircraft commonly land at night when it is dark. Being able to see the ground when coming in for a landing is important because they need to touch down at a reasonable speed. So not to put too fine a point on it, they are so the pilots can see when it is dark. You know, like with regular car headlights."
] |
[
13
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
da1mcw
|
why does the need to pee increase 10x when you walk into your house?
|
Psychology
|
explainlikeimfive
|
[
"f1mnm72",
"f1mlkh7"
] |
[
"Classical conditioning. Your mind recognizes certain stimuli and associates those with the ability to urinate, so when those stimuli are present, your body beings to \"prepare\" you to urinate. It is just like Pavlov's dogs starting to salivate when they heard the bells."
] |
[
12
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
6ybthg
|
why did so many Slavic countries abolish their monarchies immediately following World War 2?
|
I recently saw this post ( URL_0 ) and noticed that most of the countries near Greece had theirs abolished around 1946. I was just wondering what caused all these countries to decide to remove them then and there.
|
Culture
|
explainlikeimfive
|
[
"dmm5o9z"
] |
[
"They didn't \"decide\" a damn thing. Each of those countries was occupied by the Soviets after the war, who supported the rise of communist governments. Those governments, in accordance with communist ideology, abolished the existing monarchies. Also, \"Slavic\" does not mean \"Eastern European\". Hungary, Romania, and Albania, 3 of the countries you were referring to, are not Slavic."
] |
[
11
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
cbf08b
|
The almost surely probability concept
|
Mathematics
|
explainlikeimfive
|
[
"etf0hjs"
] |
[
"Think about throwing an infinitely-pointy dart at a square poster that you can measure infinitely well, to an infinite precision and accuracy. This poster is half red and half blue, cut across in a diagonal line. You throw the dart perfectly at random, and you always hit one spot on the poster: the red side 50% of the time, and the blue side 50% of the time. What are the odds of getting your dart to land exactly on the diagonal? Well, it's zero. Not just super, super unlikely, like randomly shuffling two decks of cards of having them come out identically, but actually *zero* chance. The closer you zoomed in on your dartboard, the more you'd be able to see that the dart is on one side or the other, no matter how slightly. There is no point where the dart can hit the exact diagonal, because the exact diagonal has no area. It *exists* -- the blue half is the blue half, and the red half is the red half, and because there's no gradient between the two we can say it's a perfectly sharp transition between the two -- but because it has no area. The problem is, a dart landing on one of those points is in theory no less likely than it landing on any other specific point on the board, when looked at at the same scale. Mathematicians get around this by saying 'almost surely': there is a probability of 1 that the dart will land somewhere other than the border, but the border is still -- technically -- a valid place for the dart to land."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
6ywgip
|
How do you sell houses you haven't finished paying for?
|
When people are moving, they sell the house first, and then buy a new one. But how can you sell a house, for like $185,000 - when you haven't even finished paying off your mortgage?
|
Economics
|
explainlikeimfive
|
[
"dmqnywq",
"dmqq1og"
] |
[
"So say your house is worth $250000, and you still owe $185000. You have roughly $65000 in equity. You pay your realtor their cut and the rest is yours. Because when you sell your house, you sell it for what it is valued at, not for what you owe. So someone else wants to buy your house. They have 20% to put down, (lucky bastards) and their bank loans them the other $200k. They start paying their mortgage payment to their bank, and their bank cuts your bank a check, which pays off your mortgage, pays your realtor, and then whatever is left over goes to you."
] |
[
7
] |
[
[],
[]
] |
[
"url"
] |
[
"url"
] |
85dcqr
|
How do apps keep up with updates in OS(android,iOS etc.)
|
Technology
|
explainlikeimfive
|
[
"dvwkfkg"
] |
[
"Well often times they don't bother, but in general os updates are announced in advance and are fairly well documented so devs can get pre-release versions to test their app and keep up. OS updates aren't released as frequently - minor ones only a few times a year and the big ones less so - often times about once per year. Good devs interested in maintaining their app pay attention to whats happening and ensures that there aren't any show stoppers and they can release updates anytime they want."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
l5nsln
|
How does a gun work?
|
Engineering
|
explainlikeimfive
|
[
"gkvcrh7",
"gkvcb3n"
] |
[
"The basic idea is the same as shooting a spitball through a straw. High pressure in one end of a tube pushes something through the tube and out the other end. Pressure is created by burning gunpowder, an explosive that creates a lot of high pressure gas extremely quickly. A bullet is the blockage in the tube of the barrel and it is pushed out the other end at a high rate of speed. That is the basic concept. As guns became more complex and refined ideas like rifling, grooves that dig into the softer lead of the bullet and spin it to increase accuracy were invented. Cartridges were made that held the gunpowder and a pressure-sensitive igniter in place with a waterproof housing, and clips or magazines to hold multiple of them together for easy loading. Mechanisms to automatically insert, fire, and extract the cartridges add mechanical complexity to firearms. Ultimately though the same concept of action has held since the initial invention."
] |
[
8
] |
[
[],
[
"https://www.youtube.com/watch?v=MgYlFHY3WmA"
]
] |
[
"url"
] |
[
"url"
] |
|
crtoqs
|
What is the purpose of "cruise main" on a car, and should I avoid always having it on?
|
Engineering
|
explainlikeimfive
|
[
"ex985jj"
] |
[
"Cruise main just means your cruise control is on but not set to a speed. It doesn’t hurt to have it on, just means you only have to push the set button instead of turning it on then setting it to speed."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
9z5h4w
|
How does rain supposedly help with clearing smoke in the air?
|
Chemistry
|
explainlikeimfive
|
[
"ea6g7zj"
] |
[
"Smoke is made of fine particles floating in the air. If rain hits the particles, they fall to the ground. Rain also helps put out fire. Less fire = less smoke."
] |
[
5
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
656pig
|
How do allergies develop?
|
A student in our school has a severe egg allergy. She can't even be around desserts made with eggs or her throat closes up. It has made me completely curious.
|
Biology
|
explainlikeimfive
|
[
"dg7uou8"
] |
[
"Anatomy student here. Allergies are an immune response in cases where proteins (egg proteins in this case) aren't completely broken down, and the body treats it as an invasion. Symptoms such as swelling are part of the natural inflammation response in an effort to limit damage."
] |
[
3
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
etfs0y
|
How do tranquilizers work? Why can't we use tranquilizers on humans? What would happen if we did?
|
Biology
|
explainlikeimfive
|
[
"ffg28c1",
"ffg2nsk",
"ffg5k58"
] |
[
"If an animal accidentally dies due to tranquilizer it’s not really a crime if someone dies because you tranquilized them it’s man slaughter. Each persons dosage needed is different due to bodyweight so it will be easy to under or overdosed them. Meaning you can either kill them or do little to nothing most of the time. Also you run the risk of it reacting to drugs or medications they may be on. plus they are temperature sensitive so you have a very small window after you take them out of the case and you only get one shot because the gun shooting it makes the barrel hotter so the subsequent shot will get too hot."
] |
[
6
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
|
il5akg
|
why does sticking just one foot out from the duvet make ones whole body feel "cooler"?
|
Or two feet if they're lunatics.
|
Biology
|
explainlikeimfive
|
[
"g3ph3yv",
"g3pi5p7",
"g3phgi2"
] |
[
"Don't think of it as cool air coming towards your body, think of it as heat leaving your body. When you pop a foot out more heat escapes your body instantly, so it cools you down. I did a whole leg last night."
] |
[
13
] |
[
[],
[],
[]
] |
[
"url"
] |
[
"url"
] |
cq9bml
|
Does napping for a short amount of time actually help you catch up on sleep? If so, is there an ideal length of time to sleep that is the most beneficial besides just as long as you can?
|
Other
|
explainlikeimfive
|
[
"ewup38k"
] |
[
"Napping can definitely improve your focus and wakefulness, but it won't erase your sleep debt. A great number of studies have been done on napping efficacy, and it seems that the magic number is somewhere around 30 minutes. It's enough to give you a big boost, but not so much that you are able to get into REM sleep, which takes around an hour and a half to be effective and will just leave you more tired if you don't finish that cycle."
] |
[
4
] |
[
[]
] |
[
"url"
] |
[
"url"
] |
|
myb1jn
|
How do submarines navigate underwater
|
Physics
|
explainlikeimfive
|
[
"gvvh8jn"
] |
[
"Submarines, and all military ships, use an [Inertial Navigation System]( URL_0 ) that uses accelerators, gyroscopes, and a computer to accurately plot the course and location of the ship. A good INS can go months without radio or satellite contact and still be accurate."
] |
[
5
] |
[
[
"https://en.wikipedia.org/wiki/Inertial_navigation_system"
]
] |
[
"url"
] |
[
"url"
] |
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