$A$ coil of effective area $3 \text{ m}^2$ is placed at right angles to a magnetic field of induction $0.05 \text{ Wb/m}^2$. If the field is decreased to $20\%$ of its original value in $10 \text{ seconds}$, the e.m.f. induced in the coil will be (in $\text{ mV}$)

When a conducting wire $XY$ is moved towards the right,a current flows in the anti-clockwise direction in the loop. The direction of the magnetic field at point $O$ is

$A$ conducting circular coil is placed in a uniform magnetic field with the magnetic field initially directed perpendicular to the plane of the coil. In step $A$,the coil is rotated from its initial position by $60^{\circ}$ about its diameter in time $t$. In step $B$,the coil is further rotated about the same axis in the same sense by another $120^{\circ}$ in time $2t$. The ratio of the emf induced in the coil in step $A$ to that in step $B$ is:

If magnetic flux $\phi = (3t^2 - 2t + 5) \ Wb$,then what is the induced emf at $t = 2 \ s$?

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

The total charge induced in a conducting loop when it is moved in a uniform magnetic field depends on