The plates of a parallel-plate capacitor are maintained with constant potential by a battery as they are pulled apart. During this process, the amount of charge on the plates
A) must increase.
B) must remain constant.
C) must decrease.
D) could either increase or decrease. There is no way to tell from the information given.

Question

Quizplus · Accepted Answer

When the plates of a parallel-plate capacitor are pulled apart while maintaining a constant potential, the capacitance decreases. Since capacitance is defined as C = Q/V, where Q is the charge and V is the potential, and V is constant, the charge Q must decrease as C decreases.

The Plates of a Parallel-Plate Capacitor Are Maintained with Constant