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A solenoid is connected to a battery so ...

A solenoid is connected to a battery so that a steady current flows through it. If an iron core is inserted into the solenoid, then

A

will increase

B

will decrease

C

will not change

D

may increase or decrease depending upon the direction of the current

Text Solution

Verified by Experts

The correct Answer is:
B
The iron core is magnetised. Hence the magnetic field and magnetic flux are increased. As per Lenz's law, the e.m.f. produced opposes the increase in flux. This is done by decreasing the current. Option (b).
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MARVEL PUBLICATION-ELECTROMAGNETIC INDUCTION AND ALTERNATING CURRENTS -TEST YOUR GRASP - 16
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