The number of turns in the coil of an $AC$ generator is $5000$ and the area of the coil is $0.25\,m^2$. The coil is rotated at the rate of $100\,cycles/sec$ in a magnetic field of $0.2\,Wb/m^2$. The peak value of the electromotive force $(EMF)$ generated is nearly......$kV$.

At the centre of a fixed large circular coil of radius $R$,a much smaller circular coil of radius $r$ is placed. The two coils are concentric and are in the same plane. The larger coil carries a current $I$. The smaller coil is set to rotate with a constant angular velocity $\omega$ about an axis along their common diameter. Calculate the $emf$ induced in the smaller coil after a time $t$ of its start of rotation.

When a magnet is pushed in and out of a circular coil $C$ connected to a very sensitive galvanometer $G$ as shown in the adjoining diagram with a frequency $\nu$,then

Which statement is correct for the phenomenon of periodic electromagnetic induction?

$A$ square-shaped coil of area $70 \, cm^2$ having $600$ turns rotates in a magnetic field of $0.4 \, Wb/m^2$,about an axis which is parallel to one of the sides of the coil and perpendicular to the direction of the field. If the coil completes $500$ revolutions in a minute,the instantaneous emf when the plane of the coil is inclined at $60^{\circ}$ with the field will be $..........V$. (Take $\pi = \frac{22}{7}$)

In a uniform magnetic field of induction $B$,a wire in the form of a semicircle of radius $r$ rotates about the diameter of the circle with angular frequency $\omega$. The axis of rotation is perpendicular to the field. If the total resistance of the circuit is $R$,the mean power generated per period of rotation is