Can molten metal be suspended in air?

Question

I wondered if magnets could be used to hold a drop of molten liquid metal in air (not for any particular reason just because it could be done), but was disappointed when a quick Google search showed the metal would lose its magnetic traits before it melted. Are there any other forces that could be used to suspend a drop of molten liquid metal in air such as sound waves, high pressure air, electric currents, or anything else?

Answer 1

Any material that responds to a magnetic field can---IN PRINCIPLE--be suspended. Here is the problem: The magnetic force depends on the distance to the magnet. This means that---when the object gets closer--the force increases, which in turn causes it to go even closer (and faster).

This situation is called "unstable equilibrium". In theory, you can place an object at a point where the magnetic force matches the weight of the object. In practice, the slightest distubance causes the object to either fall or to accellerate towards the source of the magnetic pull.

It is analogous to the problem of balancing a billiard ball on the point of a pin. It is theoretically possible, but very difficult in practice.