If a change in current of $0.01\, A$ in one coil produces a change in magnetic flux of $1.2 \times {10^{ - 2}}\,Wb$ in the other coil, then the mutual inductance of the two coils in henries is.....$H$

A small square loop of wire of side $l$ is placed inside a large square loop of wire $L(L \gg l)$. Both loops are coplanar and their centres coincide at point $O$ as shown in figure. The mutual inductance of the system is.

If the current $30 \,A$ flowing in the primary coil is made zero in $0.1 \,sec$. The $e.m.f.$ induced in the secondary coil is $1.5 \,volt$. The mutual inductance between the coil is.....$H$

Mutual inductance of two coils can be increased by

The mutual inductance of an induction coil is $5\,H$. In the primary coil, the current reduces from $5\,A$ to zero in ${10^{ - 3}}\,s$. What is the induced emf in the secondary coil......$V$

Two conducting circular loops $A $and $B$ are placed in the same plane with their centres coinciding as shown in figure. The mutual inductance between them $1$s: