Mastering Physics: The Electric Field and Surface Charge at a Conductor

Mastering Physics: The Electric Field and Surface Charge at a Conductor?

A conductor is placed in an external electrostatic field. The external field is uniform before the conductor is placed within it. The conductor is completely isolated from any source of current or charge.

Part A

Question: Which of the following describes the electric field inside this conductor?

Answer: It is always zero.

Part B

Question: The charge density inside the conductor is:

Answer: 0

Part C

Question: Assume that at some point just outside the surface of the conductor, the electric field has magnitude E and is directed toward the surface of the conductor. What is the charge density η on the surface of the conductor at that point?

Answer: η =  −Eϵ_0