Define reactive power in an AC circuit.

Reactive power refers to the power in an alternating current (AC) circuit that is not consumed by resistive loads but is instead stored and released by inductors and capacitors. In an AC system, inductors and capacitors create a phase difference between the voltage and current. This phase difference leads to reactive power, which does not perform work but enables the functioning of devices that rely on magnetic and electric fields, such as motors and transformers.

Inductive loads, such as motors and transformers, draw reactive power to create magnetic fields, while capacitive loads generate reactive power. The alternating nature of AC allows power to flow back and forth between the source and these reactive components. Although reactive power does not contribute to the actual consumption of energy (as measured in kilowatt-hours), it is essential for maintaining voltage levels, improving stability, and ensuring efficient operation of the entire electrical system.

Understanding reactive power is crucial for optimizing power factor and ensuring that the power system runs smoothly, especially in industrial and commercial settings where large motors and other inductive loads are used.