Assertion : When ac circuit contain resistor only, its power is m… - Vidyadip

Question

Assertion : When ac circuit contain resistor only, its power is minimum.
Reason : Power of a circuit is independent of phase angle.

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Answer

(d) The power of a ac circuit is given by $P=E I \cos \phi$where $\cos \phi$ is power factor and $\phi$ is phase angle. In case of circuit containing resistance only, phase angle is zero and power factor is equal to one. Therefore power is maximum in case of circuit containing resistor only.

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