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

The $e.m.f.$ induced in a coil of wire,which is rotating in a magnetic field,does not depend on

$A$ circular coil of radius $10\, cm$ is placed in a uniform magnetic field of $3.0 \times 10^{-5}\, T$ with its plane perpendicular to the field initially. It is rotated at a constant angular speed about an axis along the diameter of the coil and perpendicular to the magnetic field so that it undergoes half a rotation in $0.2\, s$. The maximum value of $EMF$ induced (in $\mu V$) in the coil will be close to the integer $....\mu V$.

Write down the formula for the induced $emf$ in an $AC$ generator and discuss how it varies with time.

In an $AC$ generator,a rectangular coil of $100$ turns each having area $14 \times 10^{-2} \, m^2$ is rotated at $360 \, rev/min$ about an axis perpendicular to a uniform magnetic field of magnitude $3.0 \, T$. The maximum value of the emf produced 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