1. The problem statement, all variables and given/known data How do I prove that a sphere is a conductor? 2. Relevant equations E = kQ/r 3. The attempt at a solution In my mind, if a sphere is a conductor, the charges formed during induction will move to the surface of the sphere as they can move freely in the conductor, and the same polarity of the charges would cause them to move as far away from each other as possible. (Hence they would be more or less evenly distributed on the surface of the sphere. However, the suggested solution was that the proof that the conductor was a conductor would be that there would be the electric field strength inside the sphere is zero. I'm not quite sure how to work that out, but would it be because there's no charge in the centre of the sphere (due to the fact that it is a conductor) that the E would be zero? Thank you!