In an AC circuit, V rms = 200 V, I rms = 5 A and the power factor is 0.8. The average power consumed is:

⚛️ Physics · Alternating Current · NEET & JEE

In an AC circuit, Vrms = 200 V, Irms = 5 A and the power factor is 0.8. The average power consumed is:

Answer: 800 W.

A 500 W
B 640 W
C 800 W
D 1000 W

Correct answer: C. 800 W

Explanation: P = Vrms·Irms·cosφ = 200·5·0.8 = 800 W.

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.

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In an AC circuit, V<sub>rms</sub> = 200 V, I<sub>rms</sub> = 5 A and the power factor is 0.8. The average power consumed is:

Concept context

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