Question

An e.m.f. of 12 volts is induced in a given coil when the current in it changes at the rate of 48 amperes per minute. The self inductance of the coil is(a) 0.25 henry
(b) 15 henry(c) 1.5 henry(d) 9.6 henry

Answer 1

answer : option (b) 15 Henry

explanation : it is given that,

emf induced in a given coil , E = 12volts

rate of change of current , di/dt = 48 Amp/min = 48/60 = 4/5 amp/sec

we know, induced emf of a coil, E = L × di/dt

where L is self inductance of the given coil.

so, L = E/{di/dt} = 12/{3/5} = 15 Henry

hence, An e.m.f. of 12 volts is induced in a given coil when the current in it changes at the rate of 48 amperes per minute. The self inductance of the coil is 15 Henry