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
$l / L$
${l^2}/L$
$L/l$
${L^2}/l$
Two circular coils can be arranged in any of the three situations shown in the figure. Their mutual inductance will be
The mutual inductance between two coils is $1.25$ $henry$. If the current in the primary changes at the rate of $80$ $ampere/second,$ then the induced $e.m.f$ in the secondary is......$V$
Explain mutual induction and derive equation of mutual $\mathrm{emf}$.
The induction coil works on the principle of
There are two coils $\mathrm{A}$ and $\mathrm{B}$ separated by some distance. If a current of $2\mathrm{A}$ flows through $\mathrm{A}$, a magnetic flux of $10^{-2}\mathrm{Wb}$ passes through $\mathrm{B}$ ( no current through $\mathrm{B}$ ). If no current passes through $\mathrm{A}$ and a current of $1\mathrm{A}$ passes through $\mathrm{B}$, what is the flux through $\mathrm{A}$ ?