Gadgetory

so what's a voice coil is that one of those twisty cables on an older style telephone that you always seem to hit stuff with as you moved around the room no while voice coils are indeed coils of wire the term is typically used to refer to one of two things the wires that actuate the arm of a hard drive or the wires that make your speaker's go boom boom boom boom you know both of those applications benefit from the main strengths of voice coils extreme accuracy and high movement speed you see voice coils move by using something called the Lorentz force which is created by placing a coil of wire in a fixed magnetic field when current is put through the coil it turns into an electromagnet making it either be repelled or attracted to the fixed magnetic field giving you a force this force can actually be quite strong meaning that voice coils can speed up or slow down extremely quickly speakers for example can accelerate at rates in the ballpark of 800 meters per second squared or 80 G's put into context that is 16 times the acceleration required to make you lose consciousness 27 times quicker than a space shuttle launch and 211 times faster than my Lamborghini but how exactly does that make your speakers and your microphones work well for a microphone as we've covered in more depth here there's a membrane that moves back and forth as sound waves hit it these vibrations are turned into an electrical signal as a coil of wire on the back of the diaphragm moves over a magnet to turn this electrical signal back into sound the process is reversed so the electrical signal goes to the coil which moves the speaker to create your sweet sweet beats and it's the extraordinary acceleration and precision that we mentioned before that makes it possible for speakers to produce such a wide variety of sounds on demand what about computer hard drives then well you can learn more about them in an upcoming video because we realize we have to actually done one yet but in a nutshell on one side of the arm that hovers over the spinning disk like a record needle is the head which is responsible for reading or writing data on the platter and then on the other side is a voice coil this coil of wire is surrounded by a permanent magnet that yadda-yadda yoake giving you everything that you need to get your Lorentz force on so to move the arm current flows through the coil creating a force that causes it to pivot then just before the arm of the hard drive reaches its desired location the currents reversed bringing it to a stop exactly what exactly where it needs to be in fact thanks to this lightning-fast deceleration the arms of hard drives are able to be positioned within a millionth of an inch or 1/4 thousandths of a human hair Wow I got like 5 so now you might be thinking why not just use voice coil for everything that needs to move why don't we replace the Pistons in a car or use one to throw a ball for the dog well here come the downsides excessive magnetic force and excessive heat are kind of problems if you make a magnet too large it can be difficult to tame the magnetic field it generates I mean our massive voice coil wouldn't be that great if it ripped all the fillings out of your teeth or more realistically like not in a cartoon wiped the data off of everything in a 10-foot radius also anything that has a bunch of current going through a wire will tend to be a bit toasty if you've ever had your speakers emit the magic black smoke that's most likely why but this also doesn't mean that the applications and voice coils are limited to our two examples from before one of my favorite uses for them that you'll hopefully see more of in coming years our voice coil actuated camera stabilizers these are similar to gimbal image stabilizers but instead of using several rotating motors they use you guessed it voice coils to position the camera the two got it again extreme speed and accuracy this thing Wow uses badass voice coils and is so fast and so precise that it can create 2 30 FPS videos from a single 60fps camera repositioning the camera between each frame to give the illusion that there are actually two separate cameras pretty cool so to say that I'm amped to see where we're headed as they continue to develop voice coil technology would be an understatement though I can't say that I have my hopes up about a new speaker that will make Nickelback sound any more palatable do you enjoy your freelance work or you're running your small business but do you find the challenge of like managing your time and your expenses and invoicing clients and accounting overwhelming well you're in luck because in the age of the internet with there being so many opportunities for self-employed folks who don't have a full accounting background FreshBooks cloud accounting software is here to save the day it's the simplest easiest way to be more productive more organized and perhaps most importantly get paid quickly you can create and send professional-looking 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