$A$ 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 $\text{ Wb}$)?

Two coils have a mutual inductance of $0.01 \ H$. The current in the first coil changes according to the equation $I = 5 \sin(200 \pi t)$. The maximum value of the e.m.f. induced in the second coil is:

The mutual inductance between a primary and secondary circuit is $0.5 \, H$. The resistances of the primary and the secondary circuits are $20 \, \Omega$ and $5 \, \Omega$ respectively. To generate a current of $0.4 \, A$ in the secondary,the current in the primary must be changed at the rate of . . . . . . $A/s$.

Two coils of self-inductances $2\, mH$ 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......$mH$.

The number of turns of primary and secondary coils of a transformer are $5$ and $10$ respectively and the mutual inductance of the transformer is $25\,H$. Now,the number of turns in the primary and secondary of the transformer are made $10$ and $5$ respectively. The mutual inductance of the transformer in henry will be:

$A$ coil of radius '$r$' is placed on another coil (whose radius is '$R$' and current flowing through it is changing) so that their centres coincide $(R \gg r)$. If both the coils are coplanar,then the mutual inductance between them is $(\mu_0 = \text{permeability of free space})$