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Alternating Current — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsAlternating Current1 Mark
Question
Assertion : The alternating current lags behind the e.m.f. by a phase angle of $\pi / 2$, when ac flows through an inductor.
Reason : The inductive reactance increases as the frequency of ac source decreases.
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Answer

(c) When ac flows through an inductor current lags behind the emf., by phase of $\pi / 2$, inductive reactance, $X_L=\omega L=\pi \cdot 2 f . L$, so when frequency increases correspondingly inductive reactance also increases.

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