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dx4l1f
What exactly are the crystals in an LCD an what happens to them when the screen is turned off?
Technology
explainlikeimfive
{ "a_id": [ "f7npnfx", "f7o78sy" ], "text": [ "Hey, i'm gonna try to explain this :) To understand how it works, you need to know light is like a wave, which vibrates in a fixed direction in space, it's called polarization. So when lights travel in a said direction, it can be polarized in any directio...
[ "url" ]
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dxbzti
What is the creaking/cracking noise TVs make after they’ve been turned off (put on standby)
Technology
explainlikeimfive
{ "a_id": [ "f7ovtxw" ], "text": [ "Most likely the body the of TV cooling off. The motherboard, backlighting and power supply in TVs generate a decent bit of heat. As I'm sure you know things expand and shrink with heat and cold respectively. My conclusion would be that the plastic body of the TV is just...
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dxdw3e
How do recommendation engines work?
By recommendation engines, I mean the systems that Netflix, Hulu, and Amazon employ. For example say on Netflix you finish a series on Star Trek. Netflix then presents you with the you may enjoy Black Mirror, Stranger, things etc. How is it able to compute that? Is it doing so via some machine learning clustering algor...
Technology
explainlikeimfive
{ "a_id": [ "f7p7j0x", "f7p9d9e" ], "text": [ "These are big money makers, so the exact mechanics are secret. But as to how it knows which movie are SF or rom coms - the movies all have meta data, bits of additional information, this includes genre, actors, director, themes etc. That helps the compute...
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dxh1b1
Why does division of floating point numbers take a lot more time than multiplication of floats in computers?
While working on a programming related project, I was told that code should always be optimized to multiply instead of divide floating-point numbers to achieve the same result, and it could take upwards of 6 times the time just to divide than multiply. For example, 5 \* 0.5 and 5 / 2 would give the same number, but the...
Technology
explainlikeimfive
{ "a_id": [ "f7q84qs" ], "text": [ "Divide is a much more difficult operation, the best algorithms like [Euclidean Division]( URL_0 ) take many times more steps than multiplication algorithms like the lattice." ], "score": [ 15 ], "text_urls": [ [ "https://en.wikipedia.org/wiki/Divis...
[ "url" ]
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dxifbr
How Neural Network works
I'm trying to understand the core of the NN, but getting confused with mathematics and how it learns.
Technology
explainlikeimfive
{ "a_id": [ "f7reoo5", "f7u4kuo" ], "text": [ "A simple type of neural network is the *feedforward neural network.* In this model, one creates a computational model that takes data (input layer), performs some math on that data, and then passes the result to another set of \"neurons\" (a \"hidden\" la...
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dxm9p0
Sometimes i don't touch my phone screen, like hover really close to it, but it still registers as a touch, why?
Technology
explainlikeimfive
{ "a_id": [ "f7taudq", "f7sn7hd" ], "text": [ "To answer this question, we have to understand how touch screens work. 99% of touch screens you encounter use a *capacitive* system. There's also a *resistive* system, but those have many disadvantages, like only being able to register one touch at a time...
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dxmbcq
5: Why is it so hard to replace plastics with another material with similar properties?
Technology
explainlikeimfive
{ "a_id": [ "f7soiee", "f7tpnwm", "f7tw9dj", "f7sonp6" ], "text": [ "Cost: plastic is extremely cheap to produce (also to recycle), currently nothing as cheap exists so companies will keep using what makes them the most money. Properties: there actually aren't many materials with similar prope...
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dxpio3
How is computer data "compressed" with programs like Winrar? What is there to be compressed, and what happens when it's decompressed?
Technology
explainlikeimfive
{ "a_id": [ "f7u7wqd" ], "text": [ "There are a lot of repetitive things on computer files. And one of the things that compression programs do is make a variable to replace all the duplicate parts of code. Something like x = the word \"the\" so every time the word \"the\" is in a document the program can ...
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dxqk1x
Why don’t we switch games from DVDs to UBSs so there is no download?
Technology
explainlikeimfive
{ "a_id": [ "f7upiag", "f7upnlb", "f7uqyix" ], "text": [ "Cost. It costs pennies to mass produce a dvd/Blu-ray, but much more to produce USB storage. Add the increasing prevalence of faster broadband around the world making the need for physical storage media redundant, and putting games onto phys...
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dxqz85
In the 2000s, you could tell that a cell phone was about to receive a call/message because it would cause interference to audio devices (TV, stereo etc) a few seconds before the message arrived. When did this interference stop happening and why?
Technology
explainlikeimfive
{ "a_id": [ "f7x6gi6", "f7uzxbt", "f7xpvo4", "f7xu1pl", "f7xzkw6", "f7xvuyl", "f7xvusz" ], "text": [ "Old 2G phones worked by each phone sending short bursts of signal, and then not transmitting for a time to allow other phones to talk. When the phone receives a text or sets up a t...
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[ "url" ]
dxtgd5
2012 Laptop vs 2019 Laptop with Same Specs
Why does a newer laptop with specs similar to an older laptop have significantly higher Geekbench scores? For example, 2012 laptop has the following specs: 2.6 ghz, 16gb ram, two cores i7. 2019 laptop has the following specs: 2.6 ghz, 16gb ram, 6 cores i9. Are the multiple cores really that influential on Geekbench sco...
Technology
explainlikeimfive
{ "a_id": [ "f7w3q74", "f7w10d7", "f7w0tyw", "f7w17r7" ], "text": [ "This car from 1950 is much slower than this car from 2019. Why? They both have a 3 litre engine, 4 wheels, a 5 speed gearbox and a windscreen.", "Basically: 1. The RAM is substantially faster 2. The CPU has more cores, mo...
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[ "url" ]
dxzyre
How does a computer know whether a set of binary should be a number or a letter?
How does a computer when reading a file know if "01100001" is an "a" or just 97?
Technology
explainlikeimfive
{ "a_id": [ "f7xlfpk", "f7xlziy" ], "text": [ "The program that reads the file is programmed that way. From the CPU's standpoint, there's no difference. The difference is what type of variable the program uses to store the data - for example if the type is \"Integer\" then the data is treated as a num...
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[ "url" ]
dy2nlf
Why do phones have a time limit to how long they can stay underwater for? What happens to the phone after the time limit?
Technology
explainlikeimfive
{ "a_id": [ "f7xz5bn", "f7xzdf2" ], "text": [ "Phones that are water resistant are designed to have as small cracks between components as they can make. But there is still some small cracks where water can seep through. But as they are small this takes time. How fast the water enters the phone depends...
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dy37sd
Why is it that most electronics and other appliances (i.e: televisions, smartphones, keyyboards) are colored in black?
Is there a practical reason as to why everyday electronics are painted with black?
Technology
explainlikeimfive
{ "a_id": [ "f7y29xu", "f7y4s5d" ], "text": [ "Black is a color which matches any other color, followed by white and gray. A black box would not be out of place in a red, green or blue room. However if you put a green box in a red room it does not look great. Therefore if you want to make something wi...
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dy3my8
Why does it seem that pirated streaming services are hardly ever taken down?
Technology
explainlikeimfive
{ "a_id": [ "f7y7lcv" ], "text": [ "Because many of them rely on torrenting P2P, so they don’t actually host any content. You’re actually streaming from other people who are also streaming, and as such there is no server to “take down” hosting the pirated materials." ], "score": [ 3 ], "text_u...
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dy67z6
Why are you required to wear specialized eyewear when welding, and in what way the light emitted differs from another light source?
Technology
explainlikeimfive
{ "a_id": [ "f7ynu8o", "f7ynyzu", "f7z09dk", "f7ynj0x" ], "text": [ "The brightness of the arc form an arc welder is bright enough to cause damage to your retina if you looked directly at it. How it differs from other light sources, is intensity. Like the sun, the brightness is so intense that...
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dy6isv
Why do (US) phone calls coming from your saved contacts sometimes appear Unknown, unsaved or a completely different number altogether?
Technology
explainlikeimfive
{ "a_id": [ "f7ysf3g" ], "text": [ "This sounds like a bug. I would make sure your contacts, images, music, etc. Is backed up and do a factory reset on your phone. If it continues to happen after that contact your provider." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
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dy7fos
How does a website know I mistyped my card number before I even click “place order”?
Technology
explainlikeimfive
{ "a_id": [ "f7yzju9", "f7z09zz", "f7yzug6", "f7zrbfp", "f7z3i37" ], "text": [ "Part of the card number identifies the type of card so it can tell immediately if you have tried to put a debit card instead of a credit card (or vice versa) or if that part of the number doesn't match any type...
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dyb2xd
How do stenographers catch every word in court?
Technology
explainlikeimfive
{ "a_id": [ "f80i9fp", "f7zyqaq", "f7zzhk8", "f807imp", "f80ub6u", "f80wp46", "f7zyseh", "f817et0", "f81alh3" ], "text": [ "My mom was a stenographer so I can help 1. The minimum speed for a license is 300 words per minute with less that one error per minute The average dec...
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[ "url" ]
dyf223
how do traffic lights work?
Is there someone nearby watching the traffic or is it a computer and if so, how does the computer know when to do what lights?
Technology
explainlikeimfive
{ "a_id": [ "f80rt6h", "f80t507", "f80tu0a", "f80xm9p" ], "text": [ "THere is a timer mechanism and an induction loop (magnetism based) mechanism. Your car is huge metal block of steel, which has iron, and iron is magnetic. In the road there are bundles of wiring (if you go to an intersection ...
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dyheyc
Normal Form in Databases?
I’m trying to piece together from my notes, and I’ve been looking at it too long too make sense at this point. What is the difference is 1, 2, 3. 4 normal form?
Technology
explainlikeimfive
{ "a_id": [ "f818c79" ], "text": [ "So: Let's get the fundamental idea out of the way. In a database, you'd like to store data in one place, and one place only. You don't want to have it so that a single piece of information appears in multiple places in the database, nor do you want your database to be u...
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dyhzb7
how serial number generators are made
Technology
explainlikeimfive
{ "a_id": [ "f81sce8" ], "text": [ "There is no \"that\" way, how a serial number generator is made. This ranges from a simple term (equotation) to completly random strings, which are checked against a database. **This here describes the Serial-Generator, which might be used by software-companies on legal...
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dymafh
How are Dentists able to fill cavities that are between your teeth with little space to perform the operation?
Technology
explainlikeimfive
{ "a_id": [ "f81xdyo", "f82jv7g" ], "text": [ "* Small precise tools designed specifically for that procedure * Mildly elastic nature of one's teeth being able to move slightly in place without breaking, offering a little more space * Magnifying mirrors to see the area better * Drilling out the bad po...
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dyw5bx
How does free WiFi work is large public places? How are they able to get it to stretch across whole airports, malls, etc, when my WiFi barely stretches across my house?
Technology
explainlikeimfive
{ "a_id": [ "f83veeg", "f83wjjh", "f83uc3i" ], "text": [ "A facility the size of an airport with have dozens if not well over a hundred Wireless Access Points (antennas) all managed by a centralized controller. Enterprise Grade wifi gear is also significantly more powerful and reliable than what y...
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dyxi1g
How does a motherboard work and what does it do for the computer?
I get just about everything else - CPU, GPU, RAM, etc. But for some reason I can't figure out what motherboards really do or how they work.
Technology
explainlikeimfive
{ "a_id": [ "f8457jp", "f842ivm" ], "text": [ "The primary function is to connect part together. The CPU has a lot of pins that are used to communicate with different parts. Some are for communication the RAM some are PCI-E lanes to the graphic card. Because the CPU is small and you need a cooler moun...
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dyz1dd
How do targeted ads from things you've searched on a computer get to your phone? How does the tracking process work?
For example yesterday I found myself in a website I'd never been to that sells furniture. I also visited some other furniture sites. Today on my phone all the ads on my apps are for furniture I viewed it the site I'd never heard of before yesterday. How does that work?
Technology
explainlikeimfive
{ "a_id": [ "f84a7b4", "f84amnr" ], "text": [ "Is your email attached to both devices? Do you have similar accounts between the two? That's how they do it. It's just spamming the devices attached to your accounts.", "Have you ever logged in to the same account of any site on both devices? That in ...
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dz24kc
why helicopter pilots can't escape in case of danger as they do in jet and save themselves?
Technology
explainlikeimfive
{ "a_id": [ "f84p9ta", "f84xuxc", "f84pux5", "f84pb81", "f84rlqm" ], "text": [ "They can't eject straight up or else they'd be torn up by the rotors, and helicopters usually fly much lower than airplanes, so ejecting sideways likely wouldn't give them enough altitude for their parachute to...
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dz3jfu
Why are phone batteries rated with mAh (milliamper hours), but car batteries with KW (kilowatts)?
Technology
explainlikeimfive
{ "a_id": [ "f850q6h", "f852iaj" ], "text": [ "First, a correction. Car batteries don't us kW, which is a measure of power. For an electric car, batteries are typically measured kWh (kilowatt-hours). This is a measure of energy (power x time). Essentially how much \"fuel\" it has. You are correct in n...
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dz535q
Why does toggling the power off and on for your internet modem fix connection issues?
Technology
explainlikeimfive
{ "a_id": [ "f859mya" ], "text": [ "The same reason that it can fix a bunch of computer issues: turning a device off dumps everything that is in memory currently. Turning it back on loads to a known stable state. This won't help the issue if, say, someone broke a carrier line going from your house to your...
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dz73bf
What's Dijkstra's Algorithm used for in Computer Science?
Technology
explainlikeimfive
{ "a_id": [ "f85nrca" ], "text": [ "Lots of things. It's also known as 'Shortest Path First'. I can be used for networking to find the shortest route(least number of router stops when sending a message). It can be used in databases to slowly optimize the location of data based on where it is needed most. ...
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dz7qoy
Why are tech companies concerned with the thoughts, actions, and beliefs of their users?
If you go to a store, restaurant, or hire someone for home repair, they do not consider whether your beliefs are hateful, whether you use harassing language against women or minorities, or whether you believe in fake news or conspiracy theories. However, if you sign up for an account on a web site, tech companies seem ...
Technology
explainlikeimfive
{ "a_id": [ "f85saij", "f85rsat", "f85rwl1", "f86wodt", "f86i9s2", "f8727wp" ], "text": [ "It's pretty much the same in real stores, they just don't tell you, as they have the right to deny service, and that doesn't require an agreement. It depends on the online service, but in the cas...
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dz89it
how online gaming processes fast paced decision making accurately.
How could servers that serve clients across the world share packets and make decisions in speed intensive games (ex:when two players aim and shoot at the same time) and still be accurate up to the millisecond?
Technology
explainlikeimfive
{ "a_id": [ "f85ws2x" ], "text": [ "It's not up to the millisecond, there's a lot of delay involved and servers rarely run higher than 60Hz. Human reaction time is around 150-300ms so as long as the total delay is less than that isn't really much of an issue. On the how, a lot of servers just do what they...
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dze6s9
What's the difference between Blu-ray and regular CDs?
Technology
explainlikeimfive
{ "a_id": [ "f870nk9" ], "text": [ "CDs and DVDs use a red laser to read data, and Blu-ray uses a blue laser. Since the blue laser has a shorter wavelength you can fit way more onto a Blu-ray disc than on a CD or a DVD, which means clearer sound, sharper video, and more bonus material for movies." ], ...
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dze9j2
How does colorization of old black and white footage work? Do certain gray tones translate to color or does someone have to edit everything manually?
Technology
explainlikeimfive
{ "a_id": [ "f871num" ], "text": [ "There’s been attempts at using AI and procedural calculations, as yes, different colors translate to different shades of grey based on the film used - but most all are done by hand. Early on each frame was colored entirely by hand but newer techniques use object detecti...
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dzexlq
When there are multiple bluetooth speakers/headphones/devices in use in an area, how do they keep from intercepting and playing back neighbouring bluetooth signals?
Technology
explainlikeimfive
{ "a_id": [ "f8759kp", "f87c2nh" ], "text": [ "When you first set up a Bluetooth device to connect to your phone/laptop, the connection is “paired.” Pairing establishes specific codes and both Bluetooth devices and computers/phones thereafter recognize properly paired devices. PC and phone should be s...
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dzg4m2
How are computers able to turn back on after when restarting? Eg: Once the computer is shut down how does it know that it is supposed to turn back on?
Technology
explainlikeimfive
{ "a_id": [ "f87bgtf", "f87bk09" ], "text": [ "There's a small battery inside your computer that runs a separate mini computer 24/7. This mini computer is what turns the main computer back on during a restart. It also contains the system clock, which is why you can turn off your computer, wait an hour...
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dzijzk
why do apps update regularly but nothing seems to change?
Technology
explainlikeimfive
{ "a_id": [ "f87p3wp", "f87p832", "f87p40m" ], "text": [ "Most of them are just minor reconfigurations, or getting rid of glitches nobody knows about.", "It usually has to do with small bugs faced by a minority of of users, updates of libraries used by the app or improvements for a given model...
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[ "url" ]
dzj3fp
Why is there a considerable time delay in sending and receiving emails but none in messaging apps like Whatsapp or Insta ?
Technology
explainlikeimfive
{ "a_id": [ "f87y8mr", "f886z59" ], "text": [ "Email protocols are as old the internet, and go through many servers before they arrive at their destination. Whatsapp for instance uses the XMPP protocol which address some of the issue faced with email. But it wasn't meant to replace email as such, it w...
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[ "url" ]
dzkcpo
Voyager 1 is nearly 12 billion miles from earth and is still able to communicate and transmit data to Earth. So how it's possible to lose cell connection by simply standing in the wrong part of a house it staggering.
Technology
explainlikeimfive
{ "a_id": [ "f883spm" ], "text": [ "There are antennas that are 70 meters in diameter listening for Voyager. There’s also not a bunch of buildings to block the signal. And there’s not 5000 other voyager probes competing for the same chunk of signal space." ], "score": [ 4 ], "text_urls": [ ...
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dzkd85
How does torrenting work? What's the difference between downloading a file with torrent and downloading a file with the web browser?
I have no background on I.T. Just really curious on how torrents work and its difference on downloads in web browsers like chrome, firefox, etc.
Technology
explainlikeimfive
{ "a_id": [ "f884j3w", "f8844u7", "f8a7p1y", "f8856mj", "f88ndmv" ], "text": [ "In the simplest sense instead of simply downloading the file in its entirety from a central server, torrents download bits and pieces of the file from other people who are after that torrent. In a normal downlo...
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dzoa1v
What is a webhook?
Technology
explainlikeimfive
{ "a_id": [ "f896pqj" ], "text": [ "Webhooks are one way that apps can send automated messages or information to other apps. They're a simple way your online accounts can \"speak\" to each other and get notified automatically when something new happens. There are two ways your apps can communicate with ea...
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dzp8hk
What is actually changing when Windows does an update, And why does it take so long?
I've just sat through a windows update that took around 40 minutes to install. What has actually been changed in my PC? Also, a couple of supplementary questions, why does it take so long and why did my PC have to re-start 3 or 4 times during the process?
Technology
explainlikeimfive
{ "a_id": [ "f896h14" ], "text": [ "It depends entirely on the specific update. If it's just some virus definition update for Windows Defender it probably doesn't need to reboot and can happen in the background without you knowing. If it's more integral to the operating system, it may be replacing core sy...
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[ "url" ]
dzpo0c
Why are screens flickering when you're trying to take a photo of them?
Technology
explainlikeimfive
{ "a_id": [ "f89a8jz", "f89jwkv", "f89poai", "f899qv3" ], "text": [ "The screens are flickering all the time. 50 or 60 or more times per second, that’s how you see movement on the screen. Our eyes however can’t see this; we can see a flicker of a few times to 10/12 times per second (and we see...
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dzr3v8
How do graphic card updates work? How do they increase effeciency?
Technology
explainlikeimfive
{ "a_id": [ "f89opiw", "f89p1bb", "f89p5tp" ], "text": [ "Among other reasons, sometimes new games expose bugs or limitations in the existing drivers, which the GPU manufacturer more or less has to fix to get the job done right.", "Turn off your PC, open the case, carfully remove all power cor...
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[ "url" ]
dzs3hn
Why are certain neighborhoods limited to specific ISPs?
In my search of ISPs, I discovered that my community is limited to only 3 different providers. Why is that? Do companies “own” specific areas?
Technology
explainlikeimfive
{ "a_id": [ "f89sdim", "f89uhrm" ], "text": [ "Sometimes it's as simple as the company not having the infrastructure to serve you yet. For instance, your neighborhood may have cable lines owned by Comcast, but fiber optic cables for AT & T have not been installed yet.", "In some (many?) cases, an ...
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[ "url" ]
dzyd65
How are films distributed to cinemas all over the world? I’m pretty sure they don’t use film reels anymore, so what do they use?
Technology
explainlikeimfive
{ "a_id": [ "f8ay361", "f8avyvu", "f8bfz93", "f8avso3", "f8b5r59", "f8axhxd", "f8bt0bf" ], "text": [ "The theater I work at gets sata hard drives from the distribution company that all the studios work with. There is only two companies in the US that we get flims from that I know o...
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dzznai
Does keeping my phone plugged in hurt the battery, and what is the best charging practice to keep my battery at maximum efficiency?
Technology
explainlikeimfive
{ "a_id": [ "f8b2rmu", "f8b0q4m" ], "text": [ "A lithium battery is happiest when it's cool and between 20% and 80% state of charge. So ideally you would slow-charge it to keep the temperature down, unplug it at 80% and plug it back in before it gets too low. Leaving it plugged in isn't great because ...
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e03nx2
Why do tires always look like they’re going backwards in videos of cars?
Technology
explainlikeimfive
{ "a_id": [ "f8bq685", "f8br57b", "f8bq6u6" ], "text": [ "The visual phenomenon of wheels going backwards in video has to do with the rotation of the wheel vs the frame rate of the video. The video is taken in frames per second, so there is not a continuous stream of video, and therefore the wheel...
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e05hdg
how is time measured electronically? Like if a circuit board times five seconds how does that physically work
Technology
explainlikeimfive
{ "a_id": [ "f8c04lv", "f8c185j", "f8c210y" ], "text": [ "If it is still the same as when I learned it (years ago), there is a crystal in the circuit board that has electricity pass through it. The energy causes the crystal to vibrate. Because it is known how fast it vibrates per second, any appli...
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[ "url" ]
e066ny
How do games display a millisecond counter if the max frame rate of a normal display is 60?
There’s simply not enough frames to display the millisecond digit but lots of timers do it anyways. Are numbers skipped? Are numbers blurred together? Is this hard coded by programmers or is it coded to just output milliseconds and whatever numbers happen to align with the refresh rate is whatever shows up?
Technology
explainlikeimfive
{ "a_id": [ "f8c4rpz", "f8c6539", "f8cfpa3" ], "text": [ "The clocks can count in milliseconds, the screen can't show it. So what you see is typically the time the frame started to draw.", "The timer keeps count, but the display only updates 60 times per second. The time itself is kept as accu...
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e07g7h
Why is the black of a TV not on a channel or in between programmes not as dark as a TV turned off?
Technology
explainlikeimfive
{ "a_id": [ "f8ccviw" ], "text": [ "Depends on what type of screen you have but many modern TVs have a backlight. The screen then blocks the light to produce a dark area most would consider to be black. The blockage is not 100% effective, so it is brighter than when the backlight is off." ], "score": ...
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[ "url" ]
e07zxe
How does active noise cancelling work?
Technology
explainlikeimfive
{ "a_id": [ "f8cgnh3" ], "text": [ "Noise cancelling headphones have a built-in microphone. This microphone catches the sounds that surround you, inverts them and plays the inverted sounds into your ears. The inverted sounds are the exact opposites of the surrounding sounds, and opposites cancel each othe...
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[ "url" ]
e089ns
how do lots of people in the same area’s Bluetooth devices work without interference?
Technology
explainlikeimfive
{ "a_id": [ "f8czj4c" ], "text": [ "One technique is by dividing the bit of the radio spectrum into channels, much like channels on a television. But there's only about a dozen channels, which isn't enough for 'lots of people'. So as well as channels, a technique called CDMA is used. Basically, you have a...
[ "url" ]
[ "url" ]
e0a1gy
Why does putting the air conditioner on 25°C in a cooling mode feel different from the same 25°C in heating mode?
Technology
explainlikeimfive
{ "a_id": [ "f8cu174", "f8ct7hk", "f8d0ams", "f8doh0j", "f8d7y28", "f8dhk97", "f8dv0hm", "f8e3q0i", "f8dt55p" ], "text": [ "The unit isn't putting out air at 25 C. If it's in cooling mode, it's putting out very cold air until the ambient temperature reaches 25 C. If it's in...
[ "url" ]
[ "url" ]
e0g57f
Keeping in mind the advancements in phone cameras and handheld cameras, why are cameras used in television studios still so bulky?
I was watching the US impeachment hearings and noticed the press videographers carrying bulky cameras, which prompted this question.
Technology
explainlikeimfive
{ "a_id": [ "f8ea53f", "f8dq4f3", "f8e5cw2", "f8ead0o" ], "text": [ "I’m a feature film camera man and advances have made our camera bodies pretty small (see the Alexa mini). However, by the time you add all the accessories we need it gets pretty big and heavy. These accessories include batter...
[ "url" ]
[ "url" ]
e0jh3p
Why skyhooks isn't a thing
Technology
explainlikeimfive
{ "a_id": [ "f8eck6y", "f8eczo4", "f8ebr99", "f8eer6k", "f8eim2o", "f8eej0k", "f8egs8h", "f8ehddx" ], "text": [ "Like many space technologies, the skyhook is a solved physics problem and is now a material science problem. Space elevators are in the exact same boat, we simply do...
[ "url" ]
[ "url" ]
e0ji72
Why are some batteries rechargeable, and some are only single use?
Also, what would happen if someone tried putting a single use battery onto a charging station?
Technology
explainlikeimfive
{ "a_id": [ "f8eg95z", "f8ezrb5", "f8ej25u", "f8etgg4" ], "text": [ "Basically, think of a battery like a balloon: it contains a bunch of air, which is like the energy in a battery, that wants to get out. With a regular battery, it is sealed completely closed and the only way to get the air ou...
[ "url" ]
[ "url" ]
e0jm3c
With all the technology, why can’t they make a vacuum quiet?
Technology
explainlikeimfive
{ "a_id": [ "f8ech5e", "f8ecnoi", "f8ed2c6", "f8f5axm" ], "text": [ "Actually, they can. The problem is that first this costs money (you'd have for instance to make a bigger vacuum to add material to dampen vibrations and noise), and second people think silent vacuums aren't powerful. There's ...
[ "url" ]
[ "url" ]
e0kpps
how do phones take your voice and make it come out of another phone?
Technology
explainlikeimfive
{ "a_id": [ "f8em8gz", "f8elblq" ], "text": [ "With modern technology, it goes like this: Your voice moves a diaphram/magnet in the microphone of your phone (or a similar technology). That magnet is inside of a coil of wire, and the moving magnet induces a small electrical current in the coil. That si...
[ "url" ]
[ "url" ]
e0n0xr
When you install a new browser it asks whether you want to transfer data from other browsers on the computer. If its that easy to retrieve data for all my accounts on a browser why stealing data is not as common as transfering files?
Technology
explainlikeimfive
{ "a_id": [ "f8f5un6", "f8f6rie", "f8fokx7" ], "text": [ "Because websites displayed *inside* your browser do not have permission to access all your files. The browser won't do it.", "All that transfer is doing is reading bookmarks, browsing history, cookies, saved form data (including usernam...
[ "url" ]
[ "url" ]
e0tc4v
Why do podcasters use headphones?
Technology
explainlikeimfive
{ "a_id": [ "f8h0l9d", "f8h0xcj" ], "text": [ "When you are working in an environment where you’re being recorded, you typically want to hear the entire program (Sfx, background music, reverb) Having speakers to do this is problematic, as they’d need to be in the same space as the folks being recorded...
[ "url" ]
[ "url" ]
e0tllm
Why, on some screens, do images appear dark and inverted when looked at from a certain angle?
Technology
explainlikeimfive
{ "a_id": [ "f8h5jtd", "f8h5t3b" ], "text": [ "All screens do is reflect light, so it will reflect light in a sudden angle. Also computer monitors have reflectors that make the light reflect in all directions to improve viewing angles.", "The screens you are talking about are called TN panels. TN ...
[ "url" ]
[ "url" ]
e0vahw
what happens if I plug a charger into my phone that's already wirelessly charging
Technology
explainlikeimfive
{ "a_id": [ "f8iu9np", "f8htf9h" ], "text": [ "The wired charger takes over. The power FET inside the phone prioritises the more effective charging method (wired, of course) and connects only to that source.", "It will continue to charge as you want it to. But you might also implode the universe s...
[ "url" ]
[ "url" ]
e0wyg7
Why is upload slower than dowload?
Technology
explainlikeimfive
{ "a_id": [ "f8iud28" ], "text": [ "Your money buys you a fixed amount of speed, which can be allocated to either upload or download. Most consumers download way more than they upload so most consumer internet is simply configured to allocate most of the speed you are buying to downloads. Business grade i...
[ "url" ]
[ "url" ]
e0zq0i
when a barcode or QR code is scanned,we get some numerical information like a multiple digit number or a few words. Isn't it more convenient and easy to write that info instead of making a bar code and then scan it to get the orignal??
Technology
explainlikeimfive
{ "a_id": [ "f8kaelz", "f8kbf3g" ], "text": [ "Barcodes are a font. Instead of seeing abcdABCD you see the bars. It's difficult for a human to read the bars, but extremely easy for a computer to read the bars, and that's what the font was designed for - input data into computers or cell phones. Typica...
[ "url" ]
[ "url" ]
e13lcy
What is a protobuf?
Technology
explainlikeimfive
{ "a_id": [ "f8m1xys" ], "text": [ "It's a standard and set of tools developed by Google for data serialization. Serialization is the process of taking structured data in a programming language and translating it into binary data that can be sent over a channel that wouldn't understand the structure, e.g....
[ "url" ]
[ "url" ]
e158rr
How can apps like Google Maps or Waze be so consistently accurate with their predictions for ETA?
I know they have satellites and data and whatnot, but I’m constantly surprised at how they’re able to predict with such high accuracy.
Technology
explainlikeimfive
{ "a_id": [ "f8mocy9", "f8mjcvr" ], "text": [ "they draw upon their large userbases to make this assumption: \"anywhere with any traffic will have at least a couple of our users caught in the traffic\". They can also take advantage of the fact that you can break down segments of a journey and make tim...
[ "url" ]
[ "url" ]
e16lss
How come you can still make emergency calls when there is no signal?
Technology
explainlikeimfive
{ "a_id": [ "f8mzrug", "f8nbd79", "f8odbf1" ], "text": [ "There is a signal if you can make emergency calls. It may not be your carrier's signal, so you can't check strength or make normal calls, but if you can make an emergency call there's a signal (there's few if any spots in the US where there...
[ "url" ]
[ "url" ]
e17vmx
What is actually being paid for when people purchase broadband or mobile data?
Not sure whether this belongs in technology or economics or both, but either way, the internet is not free to use. For people not in the know about the technical side of the internet, the whole thing seems pretty abstract, and the idea that there can be no WiFi but you can pay for magical extra internet in your phone s...
Technology
explainlikeimfive
{ "a_id": [ "f8nhk7n" ], "text": [ "It depends on what you call internet. Cell phone and wi-fi via cellular (or even old school analog) internet is a different set of technology at the customer level then home internet like cable, fibre or DSL etc. A cell phone vs. a cable connection to your house for exa...
[ "url" ]
[ "url" ]
e18e8n
Do blue-light-blocking glasses with completely clear/colorless lenses actually do anything? And if so, how?
Extra credit question: How should one shop for them if it would be so easy for a company to just sell ones that do nothing? Thanks for taking any time at all to read my curious questions and provide any answer! 😊
Technology
explainlikeimfive
{ "a_id": [ "f8nndy0", "f8oj5zf" ], "text": [ "There's not any proven evidence that blue light is harmful but if your looking for lenses with blue filter there's a product by essilor called an essential blue filter that filters 20% of blue light and if you add crizal prevencia anti glare it will give ...
[ "url" ]
[ "url" ]
e19tx1
What makes a port and connector on a computer’s limit for data transfer and why? (Ex. Usb, hdmi, thunderbolt)
Technology
explainlikeimfive
{ "a_id": [ "f8o7pk6", "f8nzmqg" ], "text": [ "Three things: 1. Physics. There is only so much information you can pump down a particular kind and length of cable and still have it be usable on the other end (bandwidth). To get more information across, you need a better cable (or multiple cables), whi...
[ "url" ]
[ "url" ]
e1cx61
Why do some street lights in America cast an orange light instead of a bright white light.
Technology
explainlikeimfive
{ "a_id": [ "f8o9z89", "f8oa151", "f8obtf6" ], "text": [ "They are called low-sodium lights, and have a warmer (more yellow) color of light. Metal Halide or LEDs are generally bluer (higher color temperature). Super ELI5, different types of materials make different colors of light.", "It's the...
[ "url" ]
[ "url" ]
e1db2b
How can mobile games support themselves by running ads for other mobile games?
I recently got into one of those shitty mobile games that runs ads between levels and I have noticed that every ad is for another mobile game. So... the more successful other app devs are at stealing your players, the more money they'll pay you. Am I the only one who sees the problem here?
Technology
explainlikeimfive
{ "a_id": [ "f8oblkk", "f8p44bg", "f8oj3gw", "f8of91l" ], "text": [ "welcome to the hyercasual game matrix where games are owned by same company. eg voodoo, ketchapp, lion studio, etc", "I think most people are missing the actual question here: a game is free, and makes its money by advert...
[ "url" ]
[ "url" ]
e1e6mz
Why are CPUs overclockable? Why don’t manufacturers just increase the base clock speed?
Technology
explainlikeimfive
{ "a_id": [ "f8of5zb", "f8olrzg", "f8oge2f", "f8of6o1", "f8og8qn", "f8ofaz2", "f8ohgi5", "f8ofclo", "f8oo5wi", "f8ofcu6", "f8p6d26", "f8pbgpd" ], "text": [ "They rate them at a clock speed that they feel meets a good balance of performance and reliability. By ov...
[ "url" ]
[ "url" ]
e1hfgz
How come a phone call still sounds kinda crispy in 2019? Isn’t there a better alternative
Technology
explainlikeimfive
{ "a_id": [ "f8p4w6z" ], "text": [ "Yes. They could easily make cellular calls as clear as a really good (heh) Skype or other VOIP connections. But there's a few things. Back when cell phones were starting to go digital there were still bandwidth (Im gonna skip over multiplexing and channels and stuff) is...
[ "url" ]
[ "url" ]
e1jdwt
How are space stations heated?
Technology
explainlikeimfive
{ "a_id": [ "f8pm406", "f8ppqp5", "f8r5wiu", "f8qhj9i", "f8qdmke", "f8qdpzt", "f8qf444", "f8qlmq7", "f8riklq", "f8r8ra9", "f8qp9v6", "f8rp2b0" ], "text": [ "The sun. Spacecraft are generally amost entirely in direct sunlight, and have no atmosphere or anything t...
[ "url" ]
[ "url" ]
e1jz5a
How do helicopters and planes fly in the dark?
Technology
explainlikeimfive
{ "a_id": [ "f8pqlz4", "f8prq8b" ], "text": [ "The benefit of being up in the sky means that by and large there aren't a lot of things to hit, so you don't really need to be able to see. When it comes to planes, air traffic control keeps them at different altitudes so that if everyone is doing what th...
[ "url" ]
[ "url" ]
e1k4v4
How can we tell a picture is taken zoomed-in even with the same framing as a regular picture taken closer?
Technology
explainlikeimfive
{ "a_id": [ "f8q61rt", "f8qp0oh" ], "text": [ "Zooming in is not the same as walking closer. When you walk closer, your perspective is also changing because you are viewing the subject from a different spot. When you zoom in, you are making the subject bigger without changing perspective, which is not...
[ "url" ]
[ "url" ]
e1kh52
How do GPS calculate the shortest route to a destination
Technology
explainlikeimfive
{ "a_id": [ "f8puogf", "f8pzlcj", "f8q1qsb" ], "text": [ "GPS only provides your position. Your device, smartphone, whatever, calculates the path. It does this through data, what Google calls \"map data\", which defines the time to go between each point in the road network where you have an opport...
[ "url" ]
[ "url" ]
e1novm
If we can stream 4k content over wifi, why aren't HDMI cables slowly getting replaced by wireless transmitters ?
Technology
explainlikeimfive
{ "a_id": [ "f8qma1e", "f8rbhf1", "f8qlycq", "f8qvr2e" ], "text": [ "Because the stream is compressed, where as display signal isn't. If it were you'd require a relatively powerful computer on the other end to decompress it, also there's the issue of image quality. Uncompressed 4k24fps movie s...
[ "url" ]
[ "url" ]
e1nvf6
What are the benefits of a chiplet design for microprocessors as opposed to a monolithic design?
AMD has been making waves in the past few years by popularizing the "chiplet" design in their consumer and enterprise CPUs, where there are multiple silicon dies on a package, each serving specific functions. What are the advantages and disadvantages of this compared to the traditional chip design philosophy of putting...
Technology
explainlikeimfive
{ "a_id": [ "f8qq4na", "f8qocn8" ], "text": [ "The manufacturing process of a CPU is not perfect. Dies are made from giant wafers that are slices of silicon crystals grown in a cylinder in a lab. Some of these crystals have imperfections on them and when you make a die out of one of these wafers with ...
[ "url" ]
[ "url" ]
e1nwka
How does WinRAR password encryption work?
I meant how does it encrypt my files, what does it do when I set a password?
Technology
explainlikeimfive
{ "a_id": [ "f8qunjq" ], "text": [ "File encryption can be done in a lot of different ways, but the most common is to run the files through an algorithm that changes each number. As I'm sure you know, a computer file is made of a bunch of numbers, designated as 1's and 0's. Each 1 or 0 is called a bit, an...
[ "url" ]
[ "url" ]
e1nzrt
what’s the difference between a data scientist and a data analyst?
Technology
explainlikeimfive
{ "a_id": [ "f8qoxis", "f8s71ff" ], "text": [ "At face value, an analyst would simply look at and interpret data. A scientist would collect data (experiment) and interpret it.", "Data science is a field of study that combines statistics, math, and computer science. Data scientists use complex algo...
[ "url" ]
[ "url" ]
e1o77v
How can Google display and monetize things like article snippets and images under copyright?
Technology
explainlikeimfive
{ "a_id": [ "f8qu1sl" ], "text": [ "Copyright laws allow for certain types of “fair use”, such as short clips from videos or songs to be played. A great example would be a Youtuber showing clips from somebody else’s video (or a news report) and adding their commentary about the other video. I’d imagine pa...
[ "url" ]
[ "url" ]
e1p0lp
Where do astronauts in space get their air from?
Everybody has to breathe and we on earth have an atmosphere, how is it done in space?
Technology
explainlikeimfive
{ "a_id": [ "f8qvile" ], "text": [ "They bring up water, which is converted into oxygen & hydrogen using electricity (from solar power). They also extract O2 from waste CO2." ], "score": [ 9 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
e1py0g
How Were Old Maps Drawn?
Technology
explainlikeimfive
{ "a_id": [ "f8r1slo" ], "text": [ "When you use a map or chart to navigate what you will tend to do is take bearings (measurements with a compass) which you can then draw as lines on your map/chart. Where the lines meet is where you are. You use features whose position is known (for example, spire of a c...
[ "url" ]
[ "url" ]
e1rl10
how would electric cars be any better than gasoline cars? If everyone has an car, they are going to want a lithium ion battery. Lithium is very pollutant to mine, and also we would have to throw away a ton of them when they die.
Technology
explainlikeimfive
{ "a_id": [ "f8rda1b", "f8rcj2d", "f8rdanv", "f8rh796" ], "text": [ "1. The mining of lithium is still far less pollution over the lifespan of the car/battery than burning gasoline or diesel is, and the mining for oil that it takes to make it. 1. Lithium based batteries can be recycled to a re...
[ "url" ]
[ "url" ]
e1s5yx
What is the difference between Git and Github
Technology
explainlikeimfive
{ "a_id": [ "f8rkmt5" ], "text": [ "Git is a software tool first made by the guy who made linux. It helps programmers work together. It needs someone to do computer stuff to run. GitHub is a company that does the computer stuff to run Git. They're probably the biggest company that does it. When they first...
[ "url" ]
[ "url" ]
e1ubru
What happened in the last few centuries that propelled us so far forward so quickly technology wise?
At the turn of the century we finally invent the tractor. We literally JUST invented the Tractor. 30 years later, teh automobile. roughly 40 years after that we get the first manned mission to the Moon. 20 some odd years later and the internet is born. What exactly was invented that caused this huge boom in technology?
Technology
explainlikeimfive
{ "a_id": [ "f8rttfw", "f8rtv4z", "f8ry6re", "f8rx0qo", "f8s10ge" ], "text": [ "There are three key things here First is that we learn from others and our past successes. If you invented a sled and I invented a wheel we can combine them into a cart without both of us having to invent the o...
[ "url" ]
[ "url" ]
e1w2td
Internet cookies and what happens if I don’t enable them?
Technology
explainlikeimfive
{ "a_id": [ "f8s1etd" ], "text": [ "A cookie is a piece of data that a website can ask your browser to store. Whenever you visit any page in the website, your browser will automatically send this data back to the site. Cookies are used for storing information about you. For example the first time you ente...
[ "url" ]
[ "url" ]
e1yn05
How does Disney's new "Stagecraft" technology work? How can it change the way we make and see movies?
I searched the sub and it seems like nobody else asked this question before, so here we are. Recently I've read a few articles about how Disney's new Mandalorian TV show is [using some fancy new tech]( URL_0 ) to make movies. I tried delving deeper, but the explanations seem to only make me more confused!
Technology
explainlikeimfive
{ "a_id": [ "f8seyzh" ], "text": [ "From what I understand Stagecraft just takes the concept of a green screen but realizes it via actual screens onset, and will actually move the background images to match camera movements. So traditionally when they’re shooting a movie in CG the actors are just in a big...
[ "url" ]
[ "url" ]
e1ytxo
Why and how do devices charge faster while in airplane mode?
Technology
explainlikeimfive
{ "a_id": [ "f8sfpwt" ], "text": [ "When in airplane mode (or when shut off) the device is draining less power from the power cord and battery so more energy goes to charging the battery as airplane mode disables certain services that can drain the battery. It's like if you are filling a bucket, if the bu...
[ "url" ]
[ "url" ]
e209a0
I get ads on Instagram for restaurants or products I’ve only talked about but never searched. How do they do this? Are they really listening in to me?
Technology
explainlikeimfive
{ "a_id": [ "f8svpzy", "f8sq62t", "f8sq1a8", "f8sxcvr", "f8svhkb" ], "text": [ "A lot of people will say that your phone is listening to you through the microphone. Facebook and other companies say they don't, and I'm inclined to believe them, *because they don't need to*. You say that you...
[ "url" ]
[ "url" ]
e20m60
Why is there a stereotype of it being better to developing applications inside Linux vs Windows?
Technology
explainlikeimfive
{ "a_id": [ "f8sseid", "f8sy8ji", "f90d550" ], "text": [ "Linux was historically a lot easier to develop for, I suppose. In Windows you had to find some tools, often illegally if you didn't have the money to pay for them. In Linux they're all there from the start, you install them the same way you...
[ "url" ]
[ "url" ]
e20rmk
What actually happens when we run out of IPv4 Addresses?
What happens when we run out of IPv4 addresses? < - Can no more devices connect to the internet?
Technology
explainlikeimfive
{ "a_id": [ "f8srxb7", "f8srxhx", "f8tciet", "f8st1ya" ], "text": [ "they've already implemented IPv6... per [Wikipedia]( URL_0 ), \"In IPv6, the address size was increased from 32 bits in IPv4 to 128 bits, thus providing up to 2^128 (approximately 3.403×1038) addresses. This is deemed suffici...
[ "url" ]
[ "url" ]
e25los
Why did Google let microsoft use chromium on edge?
Technology
explainlikeimfive
{ "a_id": [ "f8tmumt", "f8tvsy4" ], "text": [ "[Google is an advertising company, first and foremost]( URL_0 ). Everything that they do, they do to further the goal of selling more ads. Chrome, Drive, their MS Office knock-offs: their only purpose is to get people to use them and sink ever deeper into...
[ "url" ]
[ "url" ]
e26if7
What causes audio feedback, and why does it make that particular sound?
Technology
explainlikeimfive
{ "a_id": [ "f8tsic5", "f8tsgnp" ], "text": [ "When a microphone, connected to a speaker, picks up the audio that that speaker is broadcasting. Causes a loop: > Microphone detects sound > Speaker amplifies sound > Microphone detects amplified sound > Speaker further amplifies sound Rinse and repeat", ...
[ "url" ]
[ "url" ]
e27mfx
How do scientists fire something as small as a particle?
How is a scientist able to capture and observe something as impossibly small as a particle being fired at something else? The video I watched stated they do this to detect wave patterns.
Technology
explainlikeimfive
{ "a_id": [ "f8tzmrt" ], "text": [ "All you need to do is pop off an electron to make a charged ion. Then you can use magnetic fields to hold it and electric fields to accelerate it. (This is of course really hard, but I've oversimplified for ELI5.) If you're talking about a slit experiment, that's likely...
[ "url" ]
[ "url" ]
e29ubl
why Virtual Reality for PC has higher system requirements but PSVR on PS4 can support those kinds of games with allegedly underpowered hardware?
Technology
explainlikeimfive
{ "a_id": [ "f8ucaob", "f8ul1ng" ], "text": [ "It's about how well the hardware is optimized and how the software is designed. Notice that on the PS4, you're not going to get the same fidelity and smoothness that you would on a high end PC. This is because the port that's built to run on the PS4 is tu...
[ "url" ]
[ "url" ]
e2en59
why do GPUs need to support Graphics APIs (on a hardware level)
like for example "GPU XXX Suports DX12". which is touted as a feature on the retail box as well. from what I understand the API is standardized for a certain graphical pipeline to draw various stuff on screen (polygon pipeline, brightness of a pixel pipeline...etc.) and it's hardware agonistic, and it's up to GPU manuf...
Technology
explainlikeimfive
{ "a_id": [ "f8v8ncp", "f8v8r7p" ], "text": [ "A graphic API is indeed a standardized way to ask the GPU to do stuff (This includes drawing, as well as general computation). To support and API, GPUs have to be able to handle all the features that the API exposes to the programmer. This includes stuff ...
[ "url" ]
[ "url" ]