Which term describes a device that stores energy in an electrostatic field?

Which term describes a device that stores energy in an electrostatic field?

• A. Battery
• B. Diode
• C. Capacitor
• D. Resistor

Answer: (C)

A capacitor stores energy in the electric field between two conductors separated by a dielectric. When a voltage is applied, charges accumulate on the plates, creating an electrostatic field that holds the energy. The amount of energy stored is E = 1/2 C V^2, where C is the capacitance determined by plate area, separation, and the dielectric material. This makes capacitors ideal for applications like smoothing power supplies, filtering signals, and providing quick bursts of energy. The other devices don’t store energy electrostatically: a battery stores chemical energy, not just an electric field; a diode controls current, and a resistor dissipates energy as heat without storing it.

A capacitor stores energy in the electric field between two conductors separated by a dielectric. When a voltage is applied, charges accumulate on the plates, creating an electrostatic field that holds the energy. The amount of energy stored is E = 1/2 C V^2, where C is the capacitance determined by plate area, separation, and the dielectric material.

This makes capacitors ideal for applications like smoothing power supplies, filtering signals, and providing quick bursts of energy. The other devices don’t store energy electrostatically: a battery stores chemical energy, not just an electric field; a diode controls current, and a resistor dissipates energy as heat without storing it.