Question

In an AC circuit the current ______.

Options

• Always leads the voltage

• Always lags behind the voltage

• Is always in phase with the voltage

• May lead or lag behind or be in phase with the voltage

Answer 1

In an AC circuit the current may lead or lag behind or be in phase with the voltage.

Explanation:

In an AC circuit, when the voltage across two terminals of resistance changes, the current changes immediately. If voltage rises, current also rises, and when voltage falls, current also falls; hence, current and voltage are in phase. Further, as voltage rises and falls, current rises and falls, after a fraction of a second; so current flowing through the inductor is always lagging behind the voltage and current and voltage are out of phase.