An $e.m.f.$ of $100\,millivolts$ is induced in a coil when the current in another nearby coil becomes $10\, ampere$ from zero in $0.1\,second$ . The coefficient of mutual induction between the two coils will be.....$millihenry$

$AB$ is an infinitely long wire placed in the plane of rectangular coil of dimensions as shown in the figure. Calculate the mutual inductance of wire $AB$ and coil $PQRS$

The induction coil works on the principle of

A circular loop of radius $0.3\, cm$ lies parallel to a much bigger circular loop of radius $20 \,cm$. The centre of the small loop on the axis of the bigger loop. The distance between their centres is $15\, cm$. If a current of $20\, A$ flows through the smaller loop, then the flux linked with bigger loop is

In a $dc$ motor, induced $e.m.f.$ will be maximum

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.