It might be a silly question, but one of my friends just got asked this question at an oral exam, and he could not answer it, and didn't receive the answer either (Or at least he forgot).
And I've been thinking a while, and I'm not sure what would really happen.
If I take, lets say a wedding ring, made from a conducting material, placed it on a table, and turned on an external electric field, what would happen ?
The inside of the ring is field free, right ? So does anything even happen, and if so, is it only on the surface of the ring ?