A voltage has a value of V = 180 cos (t + 12°) and current

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A voltage has a value of V = 180 cos (t + 12°) and current – i = 2.5 cos (t + 5°) the power factor of the circuit is—

1. 0.978
2. 0.996
3. 0.993 lead
4. 0.993 lag

Correct Option: D

Power factor = cos (12° – 5º) = cos 7° = 0.993
The power factor is lagging because the current i = 2.5 cos (ωt + 5º) lag to the voltage,
V = 180 cos (ωt + 12º) by 7°.