Average power in AC LCR circuit:
AV_rms² / R
BV_rms × I_rms × cos φ (where φ is phase difference)
CV_rms × I_rms
DV × I / 2
Answer & Solution
Correct answer: B. V_rms × I_rms × cos φ (where φ is phase difference)
P_avg = V_rms × I_rms × cos φ. cos φ is the 'power factor'. Pure resistor: cos φ = 1. Pure L or C: cos φ = 0 (wattless current — only reactive power, no average power consumed).
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