Two identical metallic square loops $L_1$ and $L_2$ are placed next to each other with their sides parallel on a smooth horizontal table. Loop $L_1$ is fixed and a current which increases as a function of time is passed through it. Then,loop $L_2$ is

$A$ long solenoid of diameter $0.1\, m$ has $2 \times 10^4$ turns per meter. At the centre of the solenoid,a coil of $100$ turns and radius $0.01\, m$ is placed with its axis coinciding with the solenoid axis. The current in the solenoid reduces at a constant rate to $0\, A$ from $4\, A$ in $0.05\, s$. If the resistance of the coil is $10\pi^2\, \Omega$,the total charge flowing through the coil during this time is:

Consider a metal ring kept (supported by a cardboard) on top of a fixed solenoid carrying a current $I$ as per the figure. The centre of the ring coincides with the axis of the solenoid. If the current in the solenoid is switched off,what will happen to the ring?

$A$ rectangular loop of wire is coplanar with a long wire carrying current $I$. The loop is pulled to the right as indicated. What are the directions of the induced current in the loop and the magnetic forces on the left and the right sides of the loop?

The magnetic flux linked with a coil at any instant $t$ is given by $\phi = 5t^3 - 100t + 300$. The $e.m.f.$ induced in the coil at $t = 2 \ s$ is $....... \ V$.

The magnetic flux $\phi$ through a coil varies with time $t$ as shown in the diagram. Which graph best represents the variation of the induced electromotive force (e.m.f.) $E$ in the coil with time $t$?