Question

What is meant by wattless current?

Hint:

Wattless current occurs in purely inductive or capacitive circuits where the current and voltage are 90 degrees out of phase, leading to zero power consumption.

Answer 1

Wattless current refers to the current that flows in an AC circuit when the voltage and current are out of phase with each other by 90 degrees. This happens in circuits that contain purely inductive or purely capacitive elements. In such cases, the power consumed by the circuit is zero because the current and voltage are not in phase, meaning that the energy supplied to the circuit is stored and returned (in the case of inductance or capacitance) without being dissipated as heat.
For example, in a purely inductive circuit, the current lags the voltage by 90° and the power factor is zero, meaning no real power is consumed. This results in wattless current, as the average power over a complete cycle is zero.