Which component stores energy in a magnetic field?

Which component stores energy in a magnetic field?

• A. Resistors
• B. Capacitors
• C. Diodes
• D. Inductors

Answer: (D)

Energy is stored in a magnetic field by an inductor. When current flows through a coil, it creates a magnetic field, and the energy tied up in that field is W = 1/2 L I^2, where L is the inductance and I is the current. This stored magnetic energy can be released back into the circuit when the current changes, which explains why inductors resist sudden changes in current. Resistors don’t store energy—they convert it to heat. Capacitors store energy in an electric field between plates. Diodes control current flow and don’t store magnetic energy.

Energy is stored in a magnetic field by an inductor. When current flows through a coil, it creates a magnetic field, and the energy tied up in that field is W = 1/2 L I^2, where L is the inductance and I is the current. This stored magnetic energy can be released back into the circuit when the current changes, which explains why inductors resist sudden changes in current. Resistors don’t store energy—they convert it to heat. Capacitors store energy in an electric field between plates. Diodes control current flow and don’t store magnetic energy.