Same chapter3 marksDifficulty: Medium
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What is the power factor of an a.c. circuit, and what is it in a purely inductive circuit?
Original Khojo Papers practice question — not from a past board paper.
Answer
The power factor is the cosine of the phase angle between the voltage and the current, and the average power is Vrms × Irms × cos φ. In a purely inductive circuit the current lags the voltage by 90°, so cos φ is zero and no power is consumed on average.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Such a current is called a wattless current.
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