The coefficient of mutual inductance of two coils is $6\, mH$. If the current flowing in one is $2\, A$,then the induced $e.m.f.$ in the second coil will be:

$A$ transformer works on the principle of

The mutual inductance of a system of two coils does not depend on . . . . . . .

Two circuits have a coefficient of mutual induction of $0.09 \ H$. The average $e.m.f.$ induced in the secondary circuit due to a change of current from $0 \ A$ to $20 \ A$ in $0.006 \ s$ in the primary circuit will be:

Two coils $P$ and $S$ have a mutual inductance of $3 \times 10^{-3} \ H$. If the current in the coil $P$ is $I = 20 \sin(50 \pi t) \ A$,then the maximum value of the e.m.f. induced in coil $S$ is (in $V$)

If a current of $3.0 \ A$ flowing in the primary coil is reduced to zero in $0.001 \ s$,then the induced $e.m.f.$ in the secondary coil is $15000 \ V$. The mutual inductance between the two coils is (in $H$):