A 9-V battery is connected across a capacitor of 20 µF through a switch which is initially open.The amount of charge that flows from the battery to the capacitor when the switch is closed is

Question

Quizplus · Accepted Answer

The charge stored by a capacitor is given by the formula:

Q = CV

where Q is the charge, C is the capacitance, and V is the voltage across the capacitor.

When the switch is closed, the capacitor starts charging and the voltage across it increases. Since the battery supplies a constant voltage of 9 V, the voltage across the capacitor also becomes 9 V when the capacitor is fully charged.

Therefore, the charge that flows from the battery to the capacitor is:

Q = CV = (20 µF)(9 V) = 180 µC

Hence, the correct answer is D.

A 9-V Battery Is Connected Across a Capacitor of 20