I seem to be having trouble grasping a very basic principle in electromagnetism. I have been told, in numerous places, that the electric field inside a conductor is zero. (Electrostatics). Yet I keep coming across problems in the textbook like this one: "Use Gauss's Law to find the electric field inside a uniformly charged sphere (charge density 'ro')." where for Q[enclosed] = charge density * volume However, don't all the charges move to the surface of the sphere? and the electric field IN the sphere is subsequently zero?