In an ac circuit, the current in an inductor
A) leads the voltage by 90°.
B) lags the voltage by 90°.
C) is in phase with the voltage.
D) leads the voltage by π radians.
E) lags the voltage by π radians.

Question

Quizplus · Accepted Answer

In an AC circuit, the current in an inductor lags the voltage by 90°. This is because an inductor resists changes in current, so when the voltage alternates, the current takes some time to build up and follow it. This delay causes the current to lag behind the voltage by 90°. This phase difference between current and voltage in an inductor is represented as a negative imaginary number in complex notation (jωL).

In an Ac Circuit, the Current in an Inductor