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प्रश्न
Reactance of a coil is 157 Ω. On connecting the coil across a source of frequency 100 Hz, the current lags behind e.m.f. by 45°. The inductance of the coil is ...........
(a) 0·25 H
(b) 0·5 H
(c) 4 H
(d) 314H
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उत्तर
(a) 0·25 H
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