Metal rings $P$ and $Q$ are lying in the same plane where current $I$ is increasing steadily. The induced current in the metal rings is shown correctly in which figure?

The network shown in the figure is part of a complete circuit. If at a certain instant,the current $I$ is $5 \ A$ and it is decreasing at a rate of $10^3 \ A \ s^{-1}$,then $V_B - V_A$ equals.....$V$.

The physical quantity which is measured in the unit of $\text{wb A}^{-1}$ is

In a coil of resistance $10\,\Omega$,the induced current developed by changing magnetic flux through it is shown in the figure as a function of time. The magnitude of change in flux through the coil in weber is:

Write down the names of two devices which work on the principle of electromagnetic induction.

Shown in the figure is a circular loop of radius $r$ and resistance $R$. $A$ variable magnetic field of induction $B = B_0 e^{-t}$ is established inside the coil. If the key $K$ is closed,the electrical power developed right after closing the switch is equal to