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A circuit has a resistance of 12 ohm and an impendance of 15 ohm. The power factor of the circuit will be
(A) 0.4
(B) 0.8
(C) 0.125
(D) 1.25


Answer: B
(b)Power factor=\({\cos{\phi}}=\frac{{{R}}}{{{Z}}}=\frac{{12}}{{5}}=\frac{{4}}{{5}}={0.8}\).
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