I’d like to think that the video below is a result of geeky experimentation. “Let’s suspend a chunk of metal like Magneto!” I imagine someone saying. But the metal begins to heat up, glow red, and what you end up with is the video below:
You just witnessed induction heating.
The metal in the video is floating because of the intense magnetic fields inside the coil. How do you make a magnetic field? Pass an electric current through a wire, and a magnetic field forms.
It’s a very cool bit of science that we figured out a long time ago, and since then we have learned that you can intensify and concentrate these generated fields if you bend the wires into a circular coil. Such a coil is the basis for every electromagnet you have ever heard of, some so strong that they can levitate frogs.
But this process also works in reverse too (kind of). Put some metal (or another conducting material) inside a changing magnetic field and you can actually create an electric current inside it–called induction.
What you are seeing in the video above is the result of this process of induction. With alternating current (AC) zipping through the wires, an alternating magnetic field permeates the chunk of metal. Induction occurs, and electricity begins to “flow” within it.
The electrons inside the metal bludgeon and bump each other as they flow, creating heat. Keep the process going for long enough and the heat is too much for the metal to take. The only thing holding it together is the strong magnetic field. Turn off the electricity, and you end up with a mess that you’ll need more than a paper towel for.