Two coils of self inductance $2\,\,mH$ and $8\,\,mH$ are placed so close together that the effective flux in one coil is completely linked with the other. The mutual inductance between these coils is......$  mH$

Two conducting circular loops of radii $R_{1}$ and $\mathrm{R}_{2}$ 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 a pair of coils, each of $N\,turns$, is $M\,henry$. If a current of $I\, ampere$ in one of the coils is brought to zero in $t$ $second$ , the $emf$ induced per turn in the other coil, in volt, will be

A pair of adjacent coils has a mutual inductance of $1.5\; H$. If the current in one coil changes from $0$ to $20\; A$ in $0.5\; s ,$ what is the change of flux (in $Wb$) linkage with the other coil?

The mutual inductance between the rectangular loop and the long straight wire as shown in figure is $M$.

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