A 1m long calculating rod rotates with an angular frequency of 400 rad `s^(-1)` an axis normal to the rod passing through its one one end. The other end of the rod is contact with a circular metallic ring. A constant magnetic field of 0.5 T parallel to the axis everywhere. Calculate the e.m.f. developed between the centre and the ring.

Explanation

Given l = 1 m, `omega =" 400 rad" s^(-1)`
B = 0.5 T
We know that for a metallic rod rotating in a constant magnetic field, the emf induced across it is given by
`epsilon=(Bl^(2)omega)/(2)=(0.5 xx 1^(2) xx 400)/(2)`
`implies epsilon=100 V`