In an $AC$ generator,a coil with $N$ turns,all of the same area $A$ and total resistance $R$,rotates with frequency $\omega$ in a magnetic field $B$. The maximum value of emf generated in the coil is

$A$ 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 . . . . . .

$A$ coil of area $A$ and $N$ turns is rotating with angular velocity $\omega$ in a uniform magnetic field $\overrightarrow{B}$ about an axis perpendicular to $\vec{B}$. Magnetic flux $\varphi$ and induced emf $\varepsilon$ across it,at an instant when $\overrightarrow{B}$ is parallel to the plane of the coil,are:

What is the phase difference between the flux linked with a coil rotating in a magnetic field and the induced emf produced in it?

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

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