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dgjfiv
how do programmers know where to look when updating apps?
For example the latest Reddit update is this one. “Fixed an issue where clicking links would cause the app to crush” how would they know where to look to find the code that is causing issues ???
Technology
explainlikeimfive
{ "a_id": [ "f3c4h5q", "f3c51wx", "f3c5kef" ], "text": [ "They start by looking at the clicking links section of the code and reading it for potential issues. Then they make a change and see if that fixed it.", "System generated crash reports, user submitted bug reports, internal testing teams...
[ "url" ]
[ "url" ]
dgjxa3
Do people who edit videos (to remove something on the scene, for example) need to work at each individual frame/second?
Technology
explainlikeimfive
{ "a_id": [ "f3cbew9" ], "text": [ "Most of the tools you use in photo editing you can use in video. The difference is you need to animate the effect over time. So if a part you're painting out changes from the beginning or the shot to the end of the shot, you move the effect, or the edges of the effect, ...
[ "url" ]
[ "url" ]
dglfyx
Why can houses being built be rained in and on and it not be a problem?
Technology
explainlikeimfive
{ "a_id": [ "f3d3aja" ], "text": [ "Assuming you're talking about the wood-frame construction typical of the United States and Canada (which is used to some extent all over the world), the answer is that all the materials used in that phase of construction are rated for exposure to the elements (for a lim...
[ "url" ]
[ "url" ]
dgnwhb
How do barcodes work?
Technology
explainlikeimfive
{ "a_id": [ "f3dmrhz" ], "text": [ "They’re Morse code for scanners. The width of the bar and the amount of space between them can give information. There are many types and styles, but at their most used (products at the store) they send the UPC # of the product. The computer does the task of looking up ...
[ "url" ]
[ "url" ]
dgpyqp
How are millimetres of rain measured?
Title. 10mm isn't much but 10mm of rain is a fair amount. How is this measured?
Technology
explainlikeimfive
{ "a_id": [ "f3e0fiu", "f3e0u1m", "f3e0zu6" ], "text": [ "Any straight sided mm-gradiated cylinder. Diameter wont matter provided it is straight and not funneled/flared. A wider container catches more but needs more to fill to the same depth, as this relationship is linear for this shape ,we ignor...
[ "url" ]
[ "url" ]
dgq0xn
When modern computers connect to Wi-Fi, do they still essentially do the same screeching thing as dialup, only quicker and silently?
Technology
explainlikeimfive
{ "a_id": [ "f3e0m2x", "f3e1wiy", "f3e25gc", "f3e0imz" ], "text": [ "Sort of yes and sort of no. That was essentially a handshake: the two systems negotiating what connection characteristics, communication protocols, etc., they could use to talk to one another. That still happens, but the proc...
[ "url" ]
[ "url" ]
dgq21o
How was the electron beam in CRT televisions aimed and moved with such speed and pinpoint accuracy?
Technology
explainlikeimfive
{ "a_id": [ "f3e0g5k" ], "text": [ "This is really interesting, actually. The timing was driven by the 60hz ac power supplied to the TV set itself (50hz in PAL countries). Analog circuitry took this timing and, in conjunction with the analog radio waves received, scanned lines and frames (called fields)."...
[ "url" ]
[ "url" ]
dgs35l
Can fighter aircraft detect when they’ve been “locked on” like in the movies, if they can, how do they know?
Technology
explainlikeimfive
{ "a_id": [ "f3ebedz", "f3eeynw", "f3eh00o", "f3eg6jz", "f3em7z8", "f3ejccm", "f3f1gyf", "f3eg65o" ], "text": [ "Yes, it's absolutely possible for a fighter craft to know it's been locked onto. In order to home in on something, you have to know where it is, and one way to know ...
[ "url" ]
[ "url" ]
dgvlty
When my car is turned off, the gas gauge needle is well below the empty line. Does this position of the needle represent “true” emptiness of the tank, or does the line represent this?
Technology
explainlikeimfive
{ "a_id": [ "f3f828n" ], "text": [ "To know the fuel level. A float, like in the back tank of a toilet is used. It send a electrical signal to the needle on the dash of the car depending where the level of fuel is in the tank. Once the car is turned off the electric signal stop & the needle goes to let's ...
[ "url" ]
[ "url" ]
dgvnqs
How to use the M (memory) buttons on a basic calculator.
I use pretty basic calculators at work to do a lot of simple statistics and I’m always writing down the numbers I get after each part of the equation. I’m pretty sure there is a way to do all of this without having to write anything down, but I was never taught and never learned how to fully use the other functions of ...
Technology
explainlikeimfive
{ "a_id": [ "f3f6c7k" ], "text": [ "It depends on the calculator, but some work like this: The memory can store a single value. This value starts off as zero. The M+ button adds the currently displayed value to the memory. That means if the memory was previously clear, it now stores that value. M & minus;...
[ "url" ]
[ "url" ]
dgz5w6
Why is there a delay with connecting a Bluetooth device to a different device?
If you connect for example a speaker to a phone regularly. It will pair in 2-3 seconds. If you try and connect it to a laptop afterwards, the speaker will pair in 6-7 seconds. Now if you suddenly change and regularly connect the speaker to a laptop instead of the phone. Vice versa will happen. Why is this?
Technology
explainlikeimfive
{ "a_id": [ "f3g1fxt" ], "text": [ "When a device changes Bluetooth association like you describe, two things are happening. It's terminating the connection to the first device, and performing the handshaking protocols to connect to the new one. If it isn't actively connected to a different device, there'...
[ "url" ]
[ "url" ]
dgzoc7
How does fiber optic internet work?
How is data turned into light and how can data be transmitted with light?
Technology
explainlikeimfive
{ "a_id": [ "f3g9k6i" ], "text": [ "Fiber is just a transport medium for light, just like how copper is a transport medium for electricity. Within some manufacturing specs, intrared light will travel down a fiber optical cable as it snakes and bends through (typically) underground conduits and comes out t...
[ "url" ]
[ "url" ]
dh2fj6
Why do antivirus programs "quarantine" threats instead of just removing them?
Technology
explainlikeimfive
{ "a_id": [ "f3hcf8y", "f3hd3e4", "f3hcnq2" ], "text": [ "It basically comes down to: *they could be wrong*. AV programs use predictions as one form of detection. In case this prediction fails, the program does not delete the file. Allowing the user a chance to recover it.", "No program works ...
[ "url" ]
[ "url" ]
dh4qcj
How are "binned" CPU's or GPU's different from their "lower-quality" counterparts?
When a chip manufacturer makes a chip like a CPU, they occasionally "bin" these chips. Some of them are inherently better than others. What about those binned chips makes them better, though? If I were to take two CPUs with the same make and model and crack them open and smack them down under a microscope, what about t...
Technology
explainlikeimfive
{ "a_id": [ "f3iecm3", "f3ii6tw", "f3ijga4", "f3ie0fo", "f3ibhyr", "f3ilyds", "f3isjl6" ], "text": [ "CPU making isn't a perfect process. A lot of it relies on purity of the silicon wafer that's grown in a lab. Impurities in the wafer may degrade performance. Secondly, the lithogra...
[ "url" ]
[ "url" ]
dh4sxx
How are sports broadcasters able to pull accurate and very oddly specific stats instantly about what has happened on screen?
Technology
explainlikeimfive
{ "a_id": [ "f3ibb3k", "f3ibn8i", "f3idihe" ], "text": [ "They have a pretty significant (and good!) research team working for them behind the scenes before and during the game that feed them this type of info. They also have lists of players, stats, and all sorts of stuff sitting in front of them...
[ "url" ]
[ "url" ]
dhbe7u
How does the “overhead car view” camera work?
Technology
explainlikeimfive
{ "a_id": [ "f3lomiq", "f3m3thk", "f3m5r94", "f3n0icc" ], "text": [ "Some software stitches together all of the other camera views to make a view of the whole area around the car.", "Look carefully, you can't actually see anything on top of the car (it's just a stock image to add perspecti...
[ "url" ]
[ "url" ]
dhd4s8
how exactly a digital camera works. I understand that it's a lens that reflects light but then, how does that get out through wires then into a piece of digital file?
Technology
explainlikeimfive
{ "a_id": [ "f3mdyca" ], "text": [ "A lens refracts light. It creates a small upside down image. It does so on to a sensor. Which is actually a whole collection of small sensors. 16megapixels = 16,000,000 individual sensors. Each one reads the piece of the image that falls on it, recording its brightness ...
[ "url" ]
[ "url" ]
dhe2aq
Why are most coins in the world circular?
Technology
explainlikeimfive
{ "a_id": [ "f3mm9ee", "f3nkqrr", "f3mx79n", "f3ne3kq", "f3nsgvz", "f3nqllq", "f3nt4d7", "f3nyb37", "f3nrat6", "f3nwwg7", "f3o14te", "f3nq86z" ], "text": [ "It is a convenient shape, for stacking, for machines (counting and vending). A circle is the same size in...
[ "url" ]
[ "url" ]
dhjf61
How do electric cars save so much pollution even though majority of the power used to charge the cars are generated by coal or other natural gases?
The ratio? How much better are the cars even if they are being charged by those power sources and are they even better?
Technology
explainlikeimfive
{ "a_id": [ "f3oe76t", "f3oehe1", "f3of1rv", "f3ol1pi", "f3oye5j" ], "text": [ "A cars engine is way, way less efficient than a giant power plant. Even if it's ultimately powered by coal, an electric engine is way cleaner than a gasoline one simply because of the scale and the increased ef...
[ "url" ]
[ "url" ]
dhjqbd
How come smart devices like Alexa, Google, and iPhones (Siri) aren't triggered by TV commercials that say "Hey Google..." Or "Hey Siri..."?
Technology
explainlikeimfive
{ "a_id": [ "f3oghnl", "f3ogby8" ], "text": [ "Your \"smart\" device is actually pretty dumb. It's brain power is all in the cloud, so it's relatively easy for it's manufacturer to manipulate. A great real world example is Alexa and South Park's episode about it. The creators of South Park really went...
[ "url" ]
[ "url" ]
dho6ao
What are the differences between TN, VA, and IPS panels?
Technology
explainlikeimfive
{ "a_id": [ "f3p9i58" ], "text": [ "[See here] ( URL_0 ), not sure if there's a more up to date post." ], "score": [ 5 ], "text_urls": [ [ "https://www.reddit.com/r/buildapc/comments/92mb7r/updated_monitor_buying_guide/?utm_medium=android_app&utm_source=share" ] ] }
[ "url" ]
[ "url" ]
dhopvw
How does your phone know what time it is if it's battery dies?
Technology
explainlikeimfive
{ "a_id": [ "f3p8oji", "f3p8j21", "f3p8knv" ], "text": [ "In general, a dead phone battery isn't completely dead. It's just very low. The battery still has a bit more power in it, but using it damages the chemistry, so the phone doesn't. Besides that, phones can get the time from the phone network...
[ "url" ]
[ "url" ]
dhpzdt
why are there WiFi networks that still don't provide internet, even at full signal; and what is the point of such networks if not to connect to the internet?
Technology
explainlikeimfive
{ "a_id": [ "f3pehgc", "f3pel3g" ], "text": [ "Some devices use a temporary WiFi network so others can connect to them wirelessly to set them up. Or it might just be a malfunctioning router that can't connect to any wider network.", "Communication between devices inside the network. If you have 10...
[ "url" ]
[ "url" ]
dhsgm6
How do character models in video games nowadays move so fluently and realistically?
I can tell they probably aren't animated traditionally, so what do the makers of the game do to achieve that realistic movement? GTA and the latest Guitar Hero games are good examples.
Technology
explainlikeimfive
{ "a_id": [ "f3q237k", "f3q9fne", "f3q289n" ], "text": [ "Many use motion capture software to get a very precise idea of the movements and then just add small adjustments later. Other than that advanced hardware just made fluent and realistic animations easier to achieve.", "It isn't just moti...
[ "url" ]
[ "url" ]
dhuqdp
What makes video game snipers feel so different from game to game?
In Overwatch, I have very little problem aiming as Ana (hitting enemies, I know allies have larger hitboxes), and I can hit bodyshots easily as Widow. In Warframe, I can be flying around as Volt or Zephyr, and can hit headshots on most enemies while going faster than a smart car. In Team Fortress 2, I can't hit anythin...
Technology
explainlikeimfive
{ "a_id": [ "f3qnjn6", "f3qpqhh", "f3qz9er", "f3qnlnq" ], "text": [ "Hit boxes, default sensitivity, some snipers have bullet drop off, verticality, and different guns .. lots of factors play a role in how comfortable it is to snipe in one game vs another game", "It comes down to many fact...
[ "url" ]
[ "url" ]
dhyfo7
Why using RFID on IDs considered a bad idea?
Technology
explainlikeimfive
{ "a_id": [ "f3rx0ya" ], "text": [ "An RFID circuit doesn't have an on/off button, so it is always triggerable when your reader is in a 1 to 1.5 meter distance from it. It's like you are always holding up your passport for everybody to see." ], "score": [ 7 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
di1mfj
Why does speeding up a video cause the audio to become high pitched?
Technology
explainlikeimfive
{ "a_id": [ "f3ssk3k" ], "text": [ "Sound is waves. Sound pitch is determined by how many of those waves hit you every second. Double the speed of the video, double the waves every second, double the pitch." ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
di9vk4
How does capital letters in username not matter?
As title, password is capital & lowercase letter sensitive. Why is username different?
Technology
explainlikeimfive
{ "a_id": [ "f3u8kwz" ], "text": [ "a developer can set if they want something to be case sensitive or not. Login and user names (not passwords) are usually not case sensitive to make it easy on the user logging in and so that there is no confusion among users of the site about user names. For example, th...
[ "url" ]
[ "url" ]
diarpn
How do software developers name their builds?
Technology
explainlikeimfive
{ "a_id": [ "f3ufdr9" ], "text": [ "Anybody can pick whatever format they want, but in general, versions follow the major.minor.revision scheme. Major: Major, incompatible releases. 0 is for a product not done yet, 1 is the first official release, 2 happens when they basically revamp the product in such a...
[ "url" ]
[ "url" ]
dic37k
What is the importance of 7nm processors?
I’m usually really on top of things like this (I’m really into new tech and consumer electronics), but I must have gotten lost somewhere. I see a lot of companies like Apple and Microsoft as well as Youtubers like Linus Tech Tips talk about the importance of the introduction of 7nm (or below) processors, but I have no ...
Technology
explainlikeimfive
{ "a_id": [ "f3uro6l", "f3uornz" ], "text": [ "it's self explanatory. fit more transistors on a wafer and you can make more chips per wafer (each one becomes cheaper) or you can put more transistors on each chip and thus increase processing power while passively reducing heat production and energy con...
[ "url" ]
[ "url" ]
difkyt
Why is the presence of speed cameras always announced by speed limit signs around them? Isn't the point to secretly catch people speeding?
Technology
explainlikeimfive
{ "a_id": [ "f3vksyj", "f3vkp0p", "f3vlb10" ], "text": [ "The initial purpose of the police is not to catch as many people as possible but to prevent crimes from happening in the first place. When they tell you in advance that there will be speed cameras, you're less likely to drive too fast, whic...
[ "url" ]
[ "url" ]
difmn9
Why do the cameras at self checkout isles make the person look 10x worse than they do in real life?
Technology
explainlikeimfive
{ "a_id": [ "f3vlht4", "f3vpsuy", "f3vt51d", "f3vy5w6" ], "text": [ "They're slightly curved, to expand their field of view. That fish-eye lens distorts the image a bit and makes our features look exaggerated. With humans, just a little bit of distortion can make a person look pretty weird, be...
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difnyb
How do phones know the difference between just pressure being applied to the screen, or a finger?
Technology
explainlikeimfive
{ "a_id": [ "f3vn1mg" ], "text": [ "the way a modern phone touch screen works is by measuring the change in capacitance caused by the presence of your finger near the screen. Capacitance is a measure of the ability for 2 conductors to store some electrical charge between them. For example, if you have two...
[ "url" ]
[ "url" ]
dih3y8
Why do AM radio stations pause for ‘station identification’ periodically? If they just have to say the station number and call sign, why the need for the extended pause?
Technology
explainlikeimfive
{ "a_id": [ "f3vxedc" ], "text": [ "FCC regulations require radio transmission to identify themselves regularly. But why the pause? A lot of AM programming is syndicated nationally, more than one radio station is broadcasting the feed. The pause is used to allow local stations to override the feed and com...
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[ "url" ]
dihtoj
Algorithmic door locks, how do they generate specific door codes based off of a day and time?
I work in the hospitality industry, and my company is looking into using algorithmic door locks for our more remote properties. When the door locks are set up, you enter the current time and date, so there is an internal calendar and clock. These locks will generate a code based off of a customers check in day, time an...
Technology
explainlikeimfive
{ "a_id": [ "f3w1ayj" ], "text": [ "It doesn't generate a random code for the customer's multiday stay, but instead gives the customer a series of numbers, one for each day, so that when their stay is over their numbers are also up and so can't use the lock anymore." ], "score": [ 3 ], "text_u...
[ "url" ]
[ "url" ]
dij2er
How does a single wire control every pixel an entire TV screen. How can it convey enough information for that many pixels, sixty times per second?
Technology
explainlikeimfive
{ "a_id": [ "f3wc215", "f3w9h13", "f3wae32", "f3wb4ov" ], "text": [ "If you're talking about HDMI, there are many wires inside, with three separate pairs of wire operating together to carry the image information. The original (2002) spec had each pair carrying 1.65 billion bits per second for ...
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[ "url" ]
dijjty
Why do phones lose connection when flying? Isn't airplane altitude well within cell tower range?
Technology
explainlikeimfive
{ "a_id": [ "f3wd4mk", "f3whx9h", "f3wcxn4" ], "text": [ "For a couple reasons. 1. As u/AllReligionsAreTrue guessed, towers focus their antennas towards the ground, so they send and receive less well to things at high altitude. 2. Your phone is a relatively low power transmitter, and you're inside...
[ "url" ]
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dipgdv
Why can’t displays/monitors show the color true cyan?
Technology
explainlikeimfive
{ "a_id": [ "f3xaalo", "f3xnxrh", "f3y0a9w" ], "text": [ "The term \"true cyan\" is a little misleading. Cyan is a color, and there is a narrow range that's called cyan, and part of that range isn't displayable on monitors. [This graph]( URL_0 ) shows the overall space of colors and the triangles ...
[ "url" ]
[ "url" ]
dirl6n
How are IMEI numbers tracked?
> Someone mentioned IMEI pings do not carry location data with it so it seems that someone can avoid tracking as long as they keep location off. Of course you can use nearby cellular towers to figure out a general location as well but what happens in the case where location and cellular data are turned off + there is n...
Technology
explainlikeimfive
{ "a_id": [ "f3y82o3", "f3xrtdf", "f3xycgr" ], "text": [ "okay so I am just going to answer your questions and not go much further then that.... IMEI's are only, by default transmitted through cellular. If you have wifi on you will likely still broadcast to the cell tower unless you specifically t...
[ "url" ]
[ "url" ]
dix2l9
How can web browsers securely store passwords, if other browsers can import them easily?
For example, I save passwords for web sites on Google Chrome, and installing Firefox offers to import those passwords. If Chrome was storing them securely, surely Firefox shouldn't be able to access them so easily?
Technology
explainlikeimfive
{ "a_id": [ "f3zechb" ], "text": [ "They are not stored securely. But, they are stored conveniently. If your security risk is from someone with physical access to your computer, **you are screwed**. If your security problem is some script kiddie in Belarus, then the key is to have long, random, unique pas...
[ "url" ]
[ "url" ]
dj58zq
Asymmetric cryptography
Hello everyone, I'm currently trying to understand the system behind asymmetric cryptography or public-key cryptography. I know how it basically works, but so far I'm not really understanding it in depth. The metaphor I stumpled mostly upon ist the one with the lock and the key. A sends out his public key - the lock - ...
Technology
explainlikeimfive
{ "a_id": [ "f41c86n", "f41chfe" ], "text": [ "The lock analogy is an analogy, that's not how it works (which is actually the case with all analogies). Some problems in math are easier than others. If I have two numbers A and B, the best algorithm for multiplying them to calculate C is much easier tha...
[ "url" ]
[ "url" ]
dj5icd
Why aren't electric cars being developed so that depleted batteries can be swapped out for charged ones?
Technology
explainlikeimfive
{ "a_id": [ "f415c7s", "f4157cd" ], "text": [ "There are all sorts of issues with this. First of all battery technology is evolving very quickly. Your swap out idea imagines that these very expensive batteries can just sit around for a while and it won't really matter. But the reality is that a five y...
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[ "url" ]
dj74s6
What's the point of CVC or CVV om Credit Card?
If online transaction only need card number and CVC/CVV, then when the card is stolen there's no additional security layer?
Technology
explainlikeimfive
{ "a_id": [ "f41qot1", "f41ra9f", "f428aei", "f41rp6j" ], "text": [ "Probably to prevent the card from being used if you only got a stolen number from a website without CVV", "The CVV/CVC is there to protect against people who get the card number/account information without getting the phy...
[ "url" ]
[ "url" ]
dj76j8
How do a handful of GPS satellites handle the millions of users every day?
Technology
explainlikeimfive
{ "a_id": [ "f41qyrp", "f41rass", "f41r1bu", "f41yl2h", "f427m5m" ], "text": [ "GPS is a one-way technology. The satellites do not get requests from GPS devices; they broadcast a precise signal that all devices can listen to. Devices can then compare the signals from multiple satellites to...
[ "url" ]
[ "url" ]
dj8wdr
In graphics programming; what exactly is a texture?
Technology
explainlikeimfive
{ "a_id": [ "f42dr22" ], "text": [ "A texture is a 2D image that is applied to a 3D object (could be a 2D object depending on the style of your game but usually 2D uses objects called \"sprites\") to give it some appearance desired by the developer. There's a lot of more intricate details such as texture ...
[ "url" ]
[ "url" ]
djbapk
Vector Graphics
I understand that the beam is manipulated directly, and that’s what makes it different from raster, but I don’t understand how that would work or why it works and how it knows what order to do things in or why it requires different hardware or anything.
Technology
explainlikeimfive
{ "a_id": [ "f43cay4" ], "text": [ "Do you mean the old oscilloscope-style vector graphics or the modern of vector graphics?" ], "score": [ 3 ], "text_urls": [ [] ] }
[ "url" ]
[ "url" ]
djdr31
How were TV broadcasts able to be hijacked and why don’t/can’t they happen anymore? Instances such as the infamous ‘Vrillon’, ‘Max Headroom’ and ‘Captain Midnight’ incidents.
Technology
explainlikeimfive
{ "a_id": [ "f44e1zu", "f44eodo" ], "text": [ "When TV was analog radio waves, an analog transmitter of sufficient power could send a signal to nearby receivers. This was called \"pirate TV\". Today, TV is digital, and for the most part constrained to cable TV company fibers. You could transmit, and m...
[ "url" ]
[ "url" ]
djerwt
How do touchscreens "know" when skin is touching them, and/or how do they know it's just a conductive glove?
Technology
explainlikeimfive
{ "a_id": [ "f44ngkz" ], "text": [ "Touch screens typically detect capacitance. A metal glove will have way more capacitance than your finger, and so the screen knows that something is not right. Capacitance is basically an object's ability to hold electric charge. Large, conductive things have the best c...
[ "url" ]
[ "url" ]
djjk6n
How do rocket scientists know for sure that the payload is not going to crash into a space junk while being deployed to space ?
Technology
explainlikeimfive
{ "a_id": [ "f45kebj", "f45kpmi" ], "text": [ "They track every piece of junk they know of. But once you are out of orbit, space is beyond huge. Here's a example. When putting a probe out into space, and it has to pass through the asteroid field, they don't even have to check they just launch it throu...
[ "url" ]
[ "url" ]
djkonh
how does google earth have such sharp images and 3d buildings correct to the number of windows if satellites are so high up?
Technology
explainlikeimfive
{ "a_id": [ "f45pjhd", "f45pvdj", "f45s0il", "f45qf9l" ], "text": [ "When you use Google Earth satellite view and zoom in, what you're actually seeing is images from various different altitudes. Once you're close enough to see building details, this is likely an image taken by airplane or heli...
[ "url" ]
[ "url" ]
djkx7k
Why is a .zip file smaller than the file that gets extracted from it.
Technology
explainlikeimfive
{ "a_id": [ "f45qsd5", "f45r0sa" ], "text": [ "Because redundant data is compressed. The algorithm recognizes patterns and describes the patterns instead of spelling them out. An easy example: Imagine there is a file with this content: `10101010101010101010101010101010101010101010` You can replace thi...
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[ "url" ]
djmg4d
I've been told that satellite radio, some TV broadcasting, GPS, etc. all "bounce their signals off a satellite". But if satellites are in Earth's orbit, how does the signal bounce off then if they are on the other side of the earth or out of a clear path?
Technology
explainlikeimfive
{ "a_id": [ "f45y5iw" ], "text": [ "Simplest answer first - There's more than one There's not just one (for example) DishTV satellite. They have enough satellites to ensure coverage for the areas where they offer services. Secondly, for the services that offer coverage in specific area, their satellites a...
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djnb0b
How were VHS tapes mass produced?
Technology
explainlikeimfive
{ "a_id": [ "f46cbp2", "f46zbbm", "f46i0t1" ], "text": [ "Pretty much the same way that you would duplicate a tape at home: Read the video from one tape, and write it onto an empty casette. However, they were using automated machinery for this process. Since reading and writing tape also degrades ...
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djntjq
How does the flash bang work and what's the feeling being flash banged? Does it really work like in FPS games?
Technology
explainlikeimfive
{ "a_id": [ "f46tsxt", "f46cm6h", "f46dovx", "f46dgvj" ], "text": [ "> Does it really work like in FPS games? During army basic training I was, accidentally, flash-banged. The platoon had set up a bivouac for the night and we expected to be 'attacked'. I got to sleep for the first watch so nat...
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djo3iw
Why media system in cars is like 10 years behind the rest of software world, even in a completely new cars with new media systems.
Technology
explainlikeimfive
{ "a_id": [ "f46i3ch", "f46gq14" ], "text": [ "Well, for one, your vectors for software update are limited. Not a lot of head units allow software updates and those that do usually you can't just slap a USB stick in.... wait, theres no USB slot.... and press a button to update. Usually its restricted ...
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djomt3
Why do traditional alarm clocks snooze for 9 minutes each time, why not 10?
Technology
explainlikeimfive
{ "a_id": [ "f46lzqo" ], "text": [ "URL_0 Because some people a long time ago decided ten minutes was too long, so they geared the snooze to 9 minutes" ], "score": [ 6 ], "text_urls": [ [ "https://www.google.com/amp/s/www.southernliving.com/healthy-living/alarm-clock-snooze-9-minutes...
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[ "url" ]
djukpo
Why some portions of software installs take longer than others?
ELI5 Why some portions of software installs take longer than others? Today I was doing a software update for my phone. The first 32% installed really fast (matter of seconds) but then the rest seemed to crawl and move really slow. Whole install probably took 10 minutes. But based on the first 32% I was expecting it to ...
Technology
explainlikeimfive
{ "a_id": [ "f48ctxe" ], "text": [ "That's because not every install is as simple as just copying data from a compressed file from one location to another. Sometimes it needs to schedule updates of files that are open, sometimes it needs to decompress large files that are far larger than their compressed ...
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dk06c3
For what reason do banks not employ two-factor authentication to ensure the authenticity of transactions?
Technology
explainlikeimfive
{ "a_id": [ "f49jlhy" ], "text": [ "Some banks do offer 2FA tokens. My mother is an administrator for a small business and has one on her keyring for all work transactions. The administrator for a small business that I work for has one on her keyring for work transactions also. Both businesses are with di...
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dk06k4
When money is exchanged and stored electronically, what stops one from hacking this system to create virtual money?
Technology
explainlikeimfive
{ "a_id": [ "f49kpg8" ], "text": [ "The Fed has a register of how much money every bank has as well as how much money changed hands between banks every day. Every bank has a register of how much money it has, as well as every transaction it had with another bank. At the end of every day the Fed checks wit...
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dk2l23
How does a computer restart on its own?
Technology
explainlikeimfive
{ "a_id": [ "f49xtxe" ], "text": [ "Your motherboard contains a crude operating system referred to as the BIOS or Basic Input/Output System. You often see the actions of this when your computer first starts as it sometimes displays information about your computer hardware, or manufacturer logos. The respo...
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dk5eym
How does a pulse oximeter measure the blood oxygen levels without actually taking blood?
Technology
explainlikeimfive
{ "a_id": [ "f4at6uq", "f4b8u8e", "f4awcsu", "f4bmrr6", "f4bpmjm", "f4bnvpi", "f4bbffy" ], "text": [ "One side of the clip has a light and the other has a sensor. When you clip it on your finger, it shines both red visible light and infrared light through you finger and it hits the...
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dk71lr
Why are phone screens so hard to see when you film them?
We can see them very well, but cameras seem to have a hard time capturing them. Why?
Technology
explainlikeimfive
{ "a_id": [ "f4bjgx5" ], "text": [ "The screens have a refresh rate, where the entire screen is converted from one image to another like a flip book. The faster the pages flip, the better it looks to us. Cameras record in a similar way, taking pictures at a quick pace. Which when shown rapidly makes a mov...
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dk94po
How does Spotify's "Discover Weekly" work?
The title. Basically is it custom tailored on what I listen to? Is there a lag time from when I listen to music to when it will affect the playlist? What all factors into the playlist? I assume its made via an algorithm but I wonder what all goes into it and how it works, simply speaking. I have some background in codi...
Technology
explainlikeimfive
{ "a_id": [ "f4ck6cd" ], "text": [ "So I’ve heard a few things about it, but this is still just my best guess. Spotify tries to recommend you music you’d like based on what other people are listening to. Through their playlists functions and general listening stats, they can assign value to songs with res...
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dk9vo4
Why do gaming apps like Steam and Origin update so often?
Often times, there's no visible change to the app. I realize content needs to change, new games are added, etc... but I feel this can be done via a simple config file or database. If it's for bug fixes, why can't they bundle them together and release them once every few months?
Technology
explainlikeimfive
{ "a_id": [ "f4c1igl", "f4c56l1", "f4c1uwk" ], "text": [ "because software is complicated. and it runs on a wide variety of environments. some customers run in environments where they encounter bugs. other customers don't run in those environments. a release is made to fix the program so it runs b...
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dkjbfn
How does 4k video transfer work
This kept me awake all morning. If 4k video is approximately 8 million pixels and each pixel is approx 3 bytes of data, them that is about 24MB of data. If most movies are 30fps, them that is about 720MB per second bandwidth needed to transfer just the video. But somehow a 4k movie is transferred over Netflix at less t...
Technology
explainlikeimfive
{ "a_id": [ "f4g2n14", "f4g49tm", "f4g33p7", "f4g9uvg" ], "text": [ "If you were transferring 30 unrelated images per second, that would be the case. But videos are not a bunch of unrelated pictures. Videos are s sequence of lightly changed pictures. So, what we do is compare the first picture...
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dkl0ks
If all we had to do to get better TVs is fit more pixels into one screen, why did it take up so long to get up to 4K? Couldn’t we have started squeezing in those extra pixels way sooner?
Technology
explainlikeimfive
{ "a_id": [ "f4h9prm", "f4gww1g" ], "text": [ "Absolute maximum resolution isn't a useful metric for televisions Affordable resolution and screen size is a far more useful metric. You can buy an 8k TV today but the cheapest one is only 65\" and will cost you $3k. We could make a 16k TV but if it costs...
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dkphy7
Why can't 32-bit programs be run on a purely 64-bit machine i.e. macOS Catalina?
If 32-bit programs are run on less data, why does that prevent it from running on a machine with higher capabilities?
Technology
explainlikeimfive
{ "a_id": [ "f4ihjaw", "f4iwxbt", "f4iis0a", "f4imme4" ], "text": [ "Since I never had trouble running a 32-bit program on 64-bit Windows or Linux I assume that would be just MacOS then", "64-bit operating systems need a compatibility layer to run 32-bit software. On Windows this is called...
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dkqpgh
x64 means 64-bit but x86 means 32-bit?
Technology
explainlikeimfive
{ "a_id": [ "f4ivnmi", "f4jcayc", "f4iuwxs", "f4iwhtf" ], "text": [ "Back in the 70s Intel released a CPU called the 8086. They followed that up with the 80186, then the 286, 386 and 486. Each one used an instruction set built on the previous one, which meant for the most part software written...
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dkr118
How do grocery carts KNOW and lock upon leaving the premise/crossing the "yellow line"?
Technology
explainlikeimfive
{ "a_id": [ "f4j1vuy" ], "text": [ "There are lots of different mechanisms. The two common are: 1. for those that use a marker in the road to indicate, there is typically something giving of a signal buried beneath that line that when in proximity of the cart causes the cart to lock. 2. some use an RF sig...
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dku3dc
How do cable companies or satellite services get their program descriptions into their online guide and who writes them?
Technology
explainlikeimfive
{ "a_id": [ "f4k5hfr", "f4kkjvk" ], "text": [ "Most use an company like Gracenote (think a commercial version of IMDB without ratings but has future programming) as a base. It has program names with descriptions, when it will show, what channel, and even art. Then for services like DirecTV and Dish th...
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dkvs7o
How does Noise Canceling work?
Technology
explainlikeimfive
{ "a_id": [ "f4k56q0" ], "text": [ "Sound travels in waves, with a certain amplitude and frequency, which dictates the pitch and volume. Active noise cancelling, like you seem to be describing, has an external microphone that picks up what sounds are approaching the headphones. Then it generates a (usuall...
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dkwcjv
What is the problem with IPv6? The IT crowd doesn’t seem to like it.
Technology
explainlikeimfive
{ "a_id": [ "f4kafis" ], "text": [ "That's because the IT Crowd is a TV show and not a networking team. Before everything was standardized on IPv4, the world ran on Thicknet, TokenRing, FDDI, ArcNet, Ethernet and on SNA, IPX/SPX, IPv4, DecNet, OSI (for the short time that it existed). And everybody who wa...
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dkyw45
How do you "dumb down" an IA to play games on easier settings ?
Hi there ! Say you are playing or Age of Empires, against the computer. What mechanisms are used to ensure that the computer doesn't win everytime ? It knows where every unit is, can give WAY more commands per second than you, calculate the outcome of moves faster, and unlike SOME human player won't fumble around tryin...
Technology
explainlikeimfive
{ "a_id": [ "f4kqq6h" ], "text": [ "You can limit the number of actions it can execute in a time frame. I.e. \"hard = it can send 1 action per second, Easy = it can send 1 action per 2 seconds\". You can limit the resources it gets. I.e. \"Hard = every worker brings back 15 gold, Easy = every worker bring...
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dl0nvu
How exactly do “Binaural Beats” or “brain music” work? Is there real science behind this?
Technology
explainlikeimfive
{ "a_id": [ "f4lyeh7", "f4mz58f", "f4mgiuh", "f4lse1q", "f4mn7f6", "f4neezy", "f4nlumc", "f4n395g", "f4lya6f", "f4nbp7c", "f4nib4u", "f4moye0" ], "text": [ "They don't. And there isn't. It's all placebo, basically. URL_0 \"So, in summary, binaural beats certainl...
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dl1r78
What are neural networks and deep learning?
Technology
explainlikeimfive
{ "a_id": [ "f4lt65r", "f4uqlmc" ], "text": [ "Deep learning is a type of artificial intelligence and neural networks are mathematical models used to facilitate deep learning and other types of machine learning. At a very basic level, a neural network is a map of mathematical functions called nodes co...
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dl64kw
What is AWS and what sort of work is involved?
Technology
explainlikeimfive
{ "a_id": [ "f4ody01", "f4o07qe" ], "text": [ "Alcohol withdrawal syndrome is a set of symptoms that can occur following a reduction in alcohol use after a period of excessive use. Symptoms typically include anxiety, shakiness, sweating, vomiting, fast heart rate, and a mild fever. More severe symptom...
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dl6guu
What is the difference between a load balancer and a reverse proxy server?
Technology
explainlikeimfive
{ "a_id": [ "f4nn5yb" ], "text": [ "A load balancer directs incoming traffic/sessions to different nodes in a cluster or other grouping of similar servers in order to keep the load on any given server to a reasonable level. A reverse proxy server directs traffic to different servers based on what kind of ...
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dl788e
In 3D video games, why do character models start to stretch way out and spaz around when they're corrupted?
I see this 3D modeling phenomena in glitch and corruption streams all the time. At some point, the character models will begin to stretch out way more than they are supposed to, sometimes going off camera. Not to mention sometimes they look like they're seizing. Why does this happen?
Technology
explainlikeimfive
{ "a_id": [ "f4o0eqw" ], "text": [ "They don't always, bugs can manifest in very different ways. So, this can be one of a couple of things, to my knowledge. First, it could be an animation bug. It'd be really impractical to build a 3D character from a series of 2D images, so they don't. Instead, 3D models...
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dl7ve0
When inside a large group of people (at a stadium, concert, festival), why does your phones internet data stop working despite having full bars? Why does such a large presence of phones in one area limit every phones’ usability and ability to even simply send a text message?
Technology
explainlikeimfive
{ "a_id": [ "f4o4c5q", "f4o415v", "f4ojgi1", "f4oianw", "f4os97g", "f4oj1g2", "f4orwnl", "f4oll04", "f4ojepg", "f4ok0ro", "f4piylj", "f4ot8w8", "f4oq3cs", "f4p9fei" ], "text": [ "Here's another stadium related analogy... the stadium is designed to accomm...
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dl8c4m
Google Stadia
Technology
explainlikeimfive
{ "a_id": [ "f4oajqc", "f4ob6jk" ], "text": [ "It's a video game streaming application/ console. If you don't have really good internet it won't work properly. You play the game directly from the cloud instead of downloading it to a console.", "The goal is that you can effectively stream games, re...
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dlb0zx
Do products like Nespresso machines actually need to be regularly "descaled?"
Is this just a marketing tactic for consumers to purchase "descaling solution?" Is every 6 months or so actually how often a machine like this needs to be descaled?
Technology
explainlikeimfive
{ "a_id": [ "f4oxlmy" ], "text": [ "I use diluted vinegar in my coffee maker. Cheap and easy. I don’t know about those that have pods." ], "score": [ 5 ], "text_urls": [ [] ] }
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dlbuz1
Who is the owner of all the .com domain names? When I'm paying for one, what does the company actually do in order to generate it for me? It's not like they've already have it and they'll just hand it over to me. It never existed in the first place.
Technology
explainlikeimfive
{ "a_id": [ "f4p5njg", "f4p5uu0", "f4p5cqf", "f4pat35", "f4pk7qe" ], "text": [ "Websites are just files on a computer somewhere. That computer has an address, just like your house. But people would rather use a word in the browser to go directly to the site, not the series of numbers which...
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dlj067
What causes physics to appear realistic in animations / CGI?
Subtle things like how does one convey weight in movement, jumps, gait etc.? How does the human eye identify something as being readily computer generated (when done badly) w.r.t movement?
Technology
explainlikeimfive
{ "a_id": [ "f4qp2u2" ], "text": [ "There are basically three ways you can try to make something appear realistic: 1. Take what we know about how the things behave, use (or create) mathematical formulas that describe that movement, and implement those things in a computer program: Pros: Can be quick, easy...
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dlmb0l
Why are there still BLACK BARS on the top and bottom of some TV shows and movies despite viewing them on a widescreen TV?
Technology
explainlikeimfive
{ "a_id": [ "f4rolky", "f4ro6st", "f4s13o4", "f4s2b5c", "f4ropgi", "f4s7mt3", "f4rpyat", "f4s83ww", "f4s7z51", "f4skfds" ], "text": [ "The aspect ratio of the source material doesn't fit or match the aspect ratio of your screen. A widescreen HD TV is 16:9. Old non HD TV...
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dln6ik
How do domain servers (like at a company) and subdomains in Active Directory overlap with website domains/subdomains and DNS servers?
This question may sound dumb but I’m trying to understand this concept. I just assumed these two things aren’t related but I’ve been reading an introduction to networking concepts and apparently “domain trees” include subdomains and involve DNS servers. My understanding gets about as complex as this: Domains are websit...
Technology
explainlikeimfive
{ "a_id": [ "f4see9b" ], "text": [ "Ok, so basically, it works like this: When you register a domain, they enter a record for that domain that points towards your DNS server. That DNS server lists the IP addresses for the various services and subdomains you hold. AD is more than DNS, but it is a necessary...
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dlo3v7
Why do computers beep? What causes the noise, and what made beeps the universal sound of computer?
They're everywhere, seeming since the advent of electronics beeps have been used. Why?
Technology
explainlikeimfive
{ "a_id": [ "f4sfacf", "f4sf584", "f4sfbff" ], "text": [ "They are made by a tiny speaker, either on the motherboard of the device itself, or in the case itself (wired to the motherboard). Originally, beeps were used because they are very easy to create. Run voltage through a speaker wire at a spe...
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dlo52p
why do some regular bedside digital alarm clocks go out of sync by a minute or two over th eperiod of time?
Technology
explainlikeimfive
{ "a_id": [ "f4sh3fr", "f4spidi" ], "text": [ "Cheap crystal oscillators I bet. The easiest way to get an oscillating frequency wave (that can be squared into pulses used as a digital circuit 'clock' is to use a quartz crystal. If you put a voltage across one it sends out a wave at its resonant freque...
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dlp3wh
why are display sizes constantly increasing?
Technology
explainlikeimfive
{ "a_id": [ "f4svygw" ], "text": [ "Cost and demand. The cost to produce high quality large screens (and high quality very small screens) has drastically declined, in addition the types of screens we have now, such as LCD/LED screens can be made much better (And smaller) for consumers than the giant CRT s...
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dlq9vp
Browsers sometimes won't load page because there's problem with certificate. What are these certificates and who issues them? Why it's dangerous to open page with invalid one?
Technology
explainlikeimfive
{ "a_id": [ "f4tbclw", "f4tbt1h", "f4tnatc", "f4tq4vj" ], "text": [ "Certificates are basically ID's for websites. They are issued by a certificate authority that is trusted by other organizations, like the DMV with your driver's license. Your browser knows what companies it can trust to issue...
[ "url" ]
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dlr5fk
What exactly is happening when an ISP sends a refresh signal to your modem? Why does it sometimes improve the connection speed?
Technology
explainlikeimfive
{ "a_id": [ "f4twml7" ], "text": [ "Over time, the modems at both your end and the ISP end react to noise on the line by slowing down to maintain a stable connection. Resetting the calibration settings on a noisy line can temporarily make the speed faster when it goes back to the default starting speed, b...
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dltkm3
What is happening behind the scenes when a commercial on television is suddenly cut short after a few seconds before it even finishes? Is someone somewhere deciding to switch to a different commercial for time reasons?
Technology
explainlikeimfive
{ "a_id": [ "f4u9rod" ], "text": [ "Most commercials, both on TV and radio, are now automated. Trigger signals are sent using a subcarrier (part of the audio feed or video feed that is not normally visible or audible) and that triggers a computer. Most shows you see on TV have a mix of both national and l...
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dlwywf
why aren’t keyboards just abc etc, and instead qwerty?
Technology
explainlikeimfive
{ "a_id": [ "f4uqxcd", "f4ur4xn", "f4ur4un" ], "text": [ "It's a leftover from typewriters. The [Sholes and Glidden typewriter]( URL_0 ) used a ring form with typebars on them for each letter. When you hit two letters next to each other rapidly however, the typebars would collide with each other a...
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dlxk5m
What does it mean to achieve Quantum Supremacy?
How is it different that the current Super Computers?
Technology
explainlikeimfive
{ "a_id": [ "f4uxsl5", "f4uwlau" ], "text": [ "In short, they performed a calculation that would have been impossible on a regular supercomputer in any reasonable time frame. Regular computers work on data stored as 0's and 1's, precisely, and must do one operation at a time per processor. Quantum com...
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dlxs9g
What does this chip do?
Technology
explainlikeimfive
{ "a_id": [ "f4uuilg" ], "text": [ "It looks like one of those stupid mugs that play music or say something when you lift it up. It’s a simple circuit board that has a tiny piezo electric speaker. Nothing nefarious, just tacky. Let me guess the mug is like Christmas themed or birthday themed or something"...
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dlxwoi
Why is the sound quality of waiting music on phones worse than quality of spoken voice when theoretically it shouldn’t even involve any analog to digital kind of conversion ?
Technology
explainlikeimfive
{ "a_id": [ "f4uv5tn", "f4uw8mx", "f4uvqm7" ], "text": [ "Phones are optimised for frequencies in normal human speech. Music often falls outside of that range.", "The answer was posted in r/bestof five days ago: URL_0 URL_1", "Phone calls use only enough bandwidth to make speech reasonably...
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[ "url" ]
dm59k0
Why do big V8 drag cars make that constant revving noise when they are idling?
kind of sounds like the engine is revving up a little bit at regular intervals of~1 sec?
Technology
explainlikeimfive
{ "a_id": [ "f4x93i7" ], "text": [ "Its the result of having something called a radical camshaft. URL_0" ], "score": [ 4 ], "text_urls": [ [ "https://www.answers.com/Q/What_is_a_radical_camshaft" ] ] }
[ "url" ]
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dm833r
How does 'fuel efficiency' work with electric cars? I keep seeing Wh/Mi, but what does that mean? Is a high wh/mi better than a low, or is it the other way around?
Technology
explainlikeimfive
{ "a_id": [ "f4ydl1i" ], "text": [ "Watt hours are like gas. If you had a battery with 100Wh then you could hook a 100 Watt light bulb to it and the bulb would run for 1 hour. 200 Wh battery would last 2 hours in the same setup. 100Wh/mi means that you can drive 1 mile on that 100Wh battery. 200Wh/mi mean...
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dm9ksj
Why does taking an old battery in and out of the remote usually makes it work again a while longer?
Technology
explainlikeimfive
{ "a_id": [ "f4yqowv" ], "text": [ "It could also be a dirty contact that is cleaned by removing the battery, or there might be a microprocessor in the RC that needs to be reset by removing the power supply" ], "score": [ 11 ], "text_urls": [ [] ] }
[ "url" ]
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dm9vwd
. Why does slapping the remote make it work?
Technology
explainlikeimfive
{ "a_id": [ "f4ytfia", "f4yw4xi" ], "text": [ "There are flexible metal contacts holding the batteries in place and transferring electricity. These wear over time and become less flexible and/or get covered with leaking battery acid and build up corrosion. Hitting the remote may reestablish electrical...
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[ "url" ]
dmb1l0
How are compact cameras able to deliver a better optical zoom with similar quality than a dslr camera?
I jumped on the dslr train about 7 years ago but was disappointed by the lack of versatility, unless you dump thousands of dollars into lenses. My mother, on the other hand, bought a $400 compact Sony camera and it vastly outshines my Nikon DSLR. She gets 30x optical zoom whereas to get something similar for my camera,...
Technology
explainlikeimfive
{ "a_id": [ "f4z0m35" ], "text": [ "Smaller sensor. Compact cameras usually have a 2/3 inch sensor while DSLRs usually have an APS-C sensor or larger, which is 3-4 times wider and taller than a 2/3 inch sensor. The smaller the sensor, the smaller the other optical parts of the camera need to be, mainly th...
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