An air-filled parallel-plate capacitor is connected to a battery and allowed to charge up.Now a slab of dielectric material is placed between the plates of the capacitor while the capacitor is still connected to the battery.After this is done,we find that
A)the energy stored in the capacitor had decreased.
B)the voltage across the capacitor had increased.
C)the charge on the capacitor had increased.
D)the charge on the capacitor had not changed.
E)None of these choices is true.

Question

Quizplus · Accepted Answer

When a dielectric material is inserted into a capacitor that is connected to a battery, the capacitance of the capacitor increases. Since the voltage across the capacitor remains constant (because it is connected to a battery), the charge on the capacitor increases according to the formula Q = CV, where Q is the charge, C is the capacitance, and V is the voltage.

An Air-Filled Parallel-Plate Capacitor Is Connected to a Battery and Allowed