Answer: Zero (energy just oscillates).
- A Zero (energy just oscillates)
- B Maximum at resonance
- C Proportional to reactance
- D Equal to apparent power
Correct answer: A. Zero (energy just oscillates)
Explanation: Ideal L and C store and return energy each half-cycle. Net energy dissipated per full cycle = 0. This is why power factor = 0 for pure L or C.
In a pure inductor the current lags the voltage by 90° (energy is briefly stored in the magnetic field before current responds); in a pure capacitor the current leads the voltage by 90° (current must flow to build up charge before voltage rises) - the mnemonic "ELI the ICE man" keeps these straight.
Concept context
AC circuits, impedance, LCR series circuit, resonance, transformers, and power factor.