Assertion (A): If the frequency of the applied AC is doubled, then the power factor of a…
Physics · Class 12 · CBSE — Alternating Current
Assertion (A): If the frequency of the applied AC is doubled, then the power factor of a series R-L circuit decreases.
Reason (R): Power factor of series R-L circuit is given by \(\cos \phi=\frac{2 R}{R^{2}+\omega^{2} L^{2}}\) .
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Answer
(C) A is true but R is false.
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