Question

Draw a labelled diagram of an alternating current Generator. Determine the induced electromotive force by the rotation of coil in it.

Answer 1

The angle the plane of coil makes with the magnetic field is $\theta =\omega t$.

Hence the flux passing through the coil at a given time is given as

$\varphi =\overrightarrow{B}.\overrightarrow{A}$

$=BAcos\left(\omega t\right)$

Hence the emf induced in the coil at an instant of time is given as

$EMF=-\frac{d\varphi }{dt}$

$=BA\omega sin\left(\omega t\right)$