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(c) 3 H
(d) 0.67 H
-5
6. A coil of 100 turns carries a current of 5 mA and creates a magnetic flux of 10 weber. The
inductance is
(a) 0.2 mH
(b) 2.0 mH
(c) 0.02 mH
(d) 0.002 H
7. In a coil of self-induction 5 H, the rate of change of current is 2 As-1. Then emf induced in the coil
is
(a) 10 V
(b) -10 V
(c) 5 V
(d) -5 V
8. A solenoid is connected to a battery so that a steady current flows through it. If an iron core is
inserted into the solenoid, the current will
(a) increase
(b) decrease
(c) remain same
(d) first increase then decrease
9. If number of turns in primary and secondary coils is increased to two times each, the mutual
inductance
(a) becomes 4 times
(b) becomes 2 times
(c) becomes A times
(d) remains unchanged 4
10. When the rate of change oic current is unity, the induced emf is equal to
(a) thickness of coil
(b) number of turns in coil
(c) coefficient of self inductance
(d) total flux linked with coil