$A$ pair of adjacent coils has a mutual inductance of $2 \text{H}$. If the current in one coil changes from $0 \text{A}$ to $30 \text{A}$ in $0.15 \text{s}$, what is the change of flux linkage with the other coil (in $\text{ Wb}$)?

$A$ small square loop of side $a$ and one turn is placed inside a larger square loop of side $b$ and one turn $(b \gg a)$. The two loops are coplanar with their centres coinciding. If a current $I$ is passed in the square loop of side $b$,then the coefficient of mutual inductance between the two loops is

Two coils of self-inductance $25 \ mH$ and $9 \ mH$ are placed close together such that the effective flux in one coil is completely linked with the other. The mutual inductance between these coils is (in $mH$)

$A$ transformer works on the principle of

Two coils $P$ and $S$ have a mutual inductance of $\pi \text{ mH}$. The secondary coil $S$ has resistance $4 \text{ } \Omega$ and self-inductance $(60/\pi) \text{ mH}$. If the current in the primary is $I_p = 12 \sin(50\pi t)$, then the maximum value of the current induced in coil $S$ is [Take $\pi^2 = 10$] (in $\text{ A}$)

Two coils $A$ and $B$ have a coefficient of mutual inductance $M = 2 \ H$. The magnetic flux passing through coil $A$ changes by $4 \ Wb$ in $10 \ s$ due to the change in current in coil $B$. Then: