Question

A parallel-plate capacitor is connected to a battery and then disconnected. If a dielectric is inserted between the plates, what happens to (a) the capacitance and (b) the voltage?

Answer 1

a)

As the capacitor is disconnected from the battery, the charge stored inside the capacitor will remain constant.

Capacitance of the capacitor increases as dielectric is inserted inside the capacitor

, where k>1

b)

As the capacitance increases, to keep the charge inside the capacitor constant, the voltage across the capacitor will decrease.