Two coils $P$ and $Q$ are separated by some distance. When a current of $3\, A$ flows through coil $P$ a magnetic flux of $10^{-3}\, Wb$ passes through $Q$. No current is passed through $Q$. When no current passes through $P$ and a current of $2\, A$ passes through $Q$, the flux through $P$ is

The mutual inductance of a pair of coils, each of $N\,turns$, is $M\,henry$. If a current of $I\, ampere$ in one of the coils is brought to zero in $t$ $second$ , the $emf$ induced per turn in the other coil, in volt, will be

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....$millihenry$

A coil of radius $1\, cm$ and of turns $100$ is placed in the middle of a long solenoid of  radius $5\, cm$. and having $5\, turns/cm$. parallel to the axis of solenoid The mutual  inductance in millihenery will be

A small circular loop of wire of radius $a$ is located at the centre of a much larger circular wire loop of radius $b$. The two loops are in the same plane. The outer loop of radius $b$ carries an alternating current $I = I_0\, cos\, (\omega t)$ . The emf induced in the smaller inner loop is nearly

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.....$H$