Electrical component used to store electrical energy in the form of an electrostatic field.

Electrical component used to store electrical energy in the form of an electrostatic field.

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

Answer: (B)

Storing energy in an electrostatic field is what a capacitor does. A capacitor consists of two conductors separated by a dielectric. When a voltage is applied, charge collects on the plates, creating an electric field between them. The energy stored in that field is 1/2 C V^2, with C (the capacitance) depending on plate area, distance between plates, and the dielectric material. This is different from a battery, which stores energy chemically and releases it as electrical energy, and from an inductor, which stores energy in a magnetic field when current flows. A resistor simply converts energy to heat and does not store energy.

Storing energy in an electrostatic field is what a capacitor does. A capacitor consists of two conductors separated by a dielectric. When a voltage is applied, charge collects on the plates, creating an electric field between them. The energy stored in that field is 1/2 C V^2, with C (the capacitance) depending on plate area, distance between plates, and the dielectric material.

This is different from a battery, which stores energy chemically and releases it as electrical energy, and from an inductor, which stores energy in a magnetic field when current flows. A resistor simply converts energy to heat and does not store energy.