# Capacitor potential energy Formula

Capacitor potential energy Formula

The energy stored on a capacitor or potential energy can be expressed in terms of the work done by a battery, where the voltage represents energy per unit charge. The voltage V is proportional to the amount of charge which is already on the capacitor. It's expression is:

Capacitor energy = 1/2 (capacitance) * (voltage)2

The equation is:

U = 1/2 C V2

Where:

C: Capacitance

V: Voltage

U: Energy stored in the capacitor

Capacitor Potential Energy Formula Questions:

1) A capacitor is connected to a battery with a voltage of 5 V. Its capacitance is 2 μF. What is the energy stored in the capacitor?

From the energy capacitor formula:

U= 1/2 C V2 = 1/2 (2*10(-6) F)* (5 V)2

U= 25 * 10(-6) J

2) A capacitor is connected to a battery with a voltage of 5 V. It storage 0.5 μ J of energy. What is its capacitance?

From the energy capacitor formula:

U= 1/2 C V2 → C = 2 U /V2

C = 2* 0.5 *10(-6) J / (5 V)2

C= 0.04 * 10(-6) F = 0.04 μ F