$A$ coil having $1000$ turns and an area of $0.10 \ m^2$ rotates at half a revolution per second and is placed in a uniform magnetic field of $0.01 \ T$ perpendicular to the axis of rotation of the coil. The maximum emf voltage generated in the coil is . . . . . . $V$.

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

$A$ coil of $200$ turns and area $0.20 \ m^2$ is rotated at half a revolution per second and is placed in a uniform magnetic field of $0.01 \ T$ perpendicular to the axis of rotation of the coil. The maximum voltage generated in the coil is $\frac{2 \pi}{\beta} \ V$. The value of $\beta$ is . . . . . .

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 wire loop is rotated in a magnetic field,the direction of induced $emf$ changes in every

Discuss the characteristics of the induced $emf$ in an $AC$ generator.