Consider the following two cases. Case 1: A nonconducting sphere contains positive charge distributed uniformly throughout its volume. Which statements about the potential due to this sphere are true? All potentials are measured relative to infinity. (There may be more than one correct choice.)
a) The potential is highest at the center of the sphere.
b) The potential at the center of the sphere is the same as the potential at the surface.
c) The potential at the surface is higher than the potential at the center.
d) The potential at the center is the same as the potential at infinity.
e) The potential at the center of the sphere is zero.
Case 2: A conducting sphere contains a positive charge distributed uniformly over its surface. Which statements about the potential due to this sphere are true? All potentials are measured relative to infinity. Choose all that apply.
a. The potential at the center of the sphere is zero.
b. The potential is lowest, but not zero, at the center of the sphere.
c. The potential at the center is the same as the potential at infinity.
d. The potential at the surface is higher than the potential at the center.
e. The potential at the center of the sphere is the same as the potential at the surface.