Question

In an AC circuit, power is lost in only:

• A. resistance
• B. inductance
• C. capacitance
• D. all of these

Hint:

Only resistance causes real power loss; inductance and capacitance cause reactive power, which oscillates between source and reactive elements.

Answer 1

The Correct Option is A

In an alternating current (AC) circuit, power loss, which is the energy dissipated as heat, occurs only in resistive components because resistors convert electrical energy into thermal energy continuously. Inductors and capacitors, on the other hand, store energy temporarily in their magnetic and electric fields respectively, and release it back to the circuit without dissipating it as heat. As a result, ideal inductors and capacitors do not cause any power loss. The average power dissipated in these reactive components over a full AC cycle is zero. Therefore, power loss in an AC circuit is solely due to the resistive parts.