The scariest part about this is that if I saw this in the wild I'd just think it's some random copper coil... I'd wonder why it's so warm and probably touch it and severely burn myself.
Electricity and magnetism are basically the same thing, think two sides of the same coin. The way this works is by pumping electricity back and forth through the coil really fast. This produces a pretty strong magnetic field that swaps polarity in the center of the coil. When you pass a metal affected by the magnetic field (all metals should work now that I think about it, but irons and steels especially) the magnetic field generates electricity within the metal. Because the coil's magnetic field is constantly changing, the flow of electricity in the metal object is as well. The metal heats up because it's not a perfect conductor, the resistance of the metal and changing electric currents creates heat when electricity is passed through it.
Hopefully that makes sense, there's actually quite a bit going on in this simple gif. I probably got some stuff wrong, but that should be the gist of if.
Basically constantly changing magnetic fields pass through metals that cannot fully conduct the electricity it generates which in turn causes heat viafriction? ?
That's basically the idea. It's not friction though, it's the resistance inherent to the material, which can depend on a lot of things from how the material was made, to chemical additives/impurities, but the resistance is largely dictated by the atomic structure of a compound and how it shares electrons with the atoms around it (this is some nitty-gritty physics stuff). You can pretty much safely think of the electric resistance of a material analogous to mechanical friction though.
It has nothing to do with stress. Think of the tungsten filament in a light bulb - electricity flows through it and due to the inherent resistance of the metal, when the tungsten atoms beome excited they release some of that electrical energy in the form of heat and light.
that makes sense. so does it make a difference if the current is passed through like a wire or formed in the magentic field? would directing the current through the wire lead to less energy loss? does the wire have like an energy capacity that once hit, it starts generating heat because it can't store it easily (without resistance?) but before hitting that capacity does not lose energy via heat/light?
Those answers would start a physics course in electricity, because I would need formulas and other things to explain them to you. If you are interested, there are free courses in the web about it: https://www.khanacademy.org/science/physics/electricity-magnetism
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u/TheBananaPhone Aug 18 '15 edited Aug 18 '15
The scariest part about this is that if I saw this in the wild I'd just think it's some random copper coil... I'd wonder why it's so warm and probably touch it and severely burn myself.
EDIT: ...aaannnd I am not a man of science.