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When a coil is connected to a Leclanche ...

When a coil is connected to a Leclanche cell, its resistance is found to be R. What is the effect on its resistance, if it is conncected to an a.c. source?

A

it will decrease

B

it will remain the same

C

it will be zero

D

it will increase

Text Solution

Verified by Experts

The correct Answer is:
D
The coil has an inductance L and a resistance R. Hence with a.c. source its effective resistance (reactance) will be `sqrt(R^(2)+omega^(2)L^(2))`. Thus it is more than its d.c. resistance. (for d.c. L=0). With a Leclanche cell, we get its d.c. resistance .
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MARVEL PUBLICATION-ELECTROMAGNETIC INDUCTION AND ALTERNATING CURRENTS -TEST YOUR GRASP - 16
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