The coefficient of mutual induction is $2 \ H$ and the induced e.m.f. across the secondary coil is $2 \ kV$. The current in the primary coil is reduced from $6 \ A$ to $3 \ A$. The time required for the change of current is:

Two coils of self-inductance $100\,mH$ and $400\,mH$ are placed very close to each other. Find the maximum mutual inductance between the two. (The current value is irrelevant to the calculation of mutual inductance).

An alternating current with an angular frequency of $\omega = 200\,rad/s$ and a peak value of $I_0 = 1\,A$,as shown in the figure,is applied to the primary coil of a transformer. If the coefficient of mutual induction between the primary and the secondary coils is $M = 1.5\,H$,the magnitude of the induced voltage in the secondary coil will be.....$V$.

Two conducting circular loops of radii $R_{1}$ and $R_{2}$ are placed in the same plane with their centres coinciding. If $R_{1} >> R_{2}$,the mutual inductance $M$ between them will be directly proportional to:

The mutual inductance of two coils is $45 \ mH$. The self-inductance of the coils are $L_1 = 75 \ mH$ and $L_2 = 48 \ mH$. The coefficient of coupling between the two coils is

$A$ small square loop of wire of side $l$ is placed inside a large square loop of side $L$ $(L > l)$. If the loops are coplanar and their centers coincide,the mutual inductance of the system is directly proportional to