How does an inductor function in an AC circuit?

An inductor functions by storing energy in a magnetic field when electrical current passes through it. In an AC circuit, the direction and magnitude of the current change periodically. As the current changes, the magnetic field around the inductor also changes, allowing it to store energy when the current increases and release that energy when the current decreases. This property of inductors is crucial in various applications, such as filters, energy storage devices, and in managing current flow in AC systems.

The ability of inductors to oppose changes in current is known as inductance, which leads to the phenomenon of "back EMF" (electromotive force), influencing the circuit's overall impedance. This behavior distinguishes inductors from resistors, capacitors, and other circuit components, making their role in controlling current and voltage in AC circuits fundamental to the design and functionality of electrical systems.