Question

A metal disc of radius 200cm is rotated at a constant angular speed of 60rad per sec in a plane at right angles to an external uniform magnetic field of magnetic induction 0.05wb per metre square. Find emf induced b/w the centre and a point in the rim

Answer 1

$$\begin{gathered} Forceonthechargeparticlegivesthedirectionofthecurrentinduced. \\ Velocityofthechargeparticlein\tan genttothediscandmagneticfieldisperpendiculartotheplane,socurrentwillinducedbetweencentreandtheedge. \\ Inducedemfisgivenby: \\ e=\frac{B{r}^2\omega }{2} \\ e=\frac{0.05\times 200\times 200\times {10}^{-4}\times 60}{2} \\ e=6V \end{gathered}$$