An uncharged conductor has a hollow cavity inside of it.Within this cavity there is a charge of +10 µC that does not touch the conductor.There are no other charges in the vicinity.Which statement about this conductor is true? (There may be more than one correct choice.)
A) The inner surface of the conductor carries a charge of -10 µC and its outer surface carries no excess charge.
B) The inner and outer surfaces of the conductor each contain charges of -5 µC.
C) The net electric field within the material of the conductor points away from the +10 µC charge.
D) The outer surface of the conductor contains +10 µC of charge and the inner surface contains -10 µC.
E) Both surfaces of the conductor carry no excess charge because the conductor is uncharged.

Question

Quizplus · Accepted Answer

The presence of a charge inside the conductor induces opposite charges on its inner and outer surface. As the charge inside is +10 µC, the inner surface will have a net charge of -10 µC, and the outer surface will have a net charge of +10 µC to maintain the electrostatic equilibrium. Therefore, choice D is correct. Choices A and B are incorrect because the inner and outer surfaces carry opposite charges, not the same charge. Choice C is incorrect because the net electric field inside a conductor is always zero (otherwise, charges would move until it is zero). Choice E is incorrect because while the conductor as a whole is uncharged, there are charges on its surfaces due to the presence of the internal charge.

An Uncharged Conductor Has a Hollow Cavity Inside of It