Rod `PQ` of length `2l` is rotating about one end `P` in a uniform magnetic field `B` which is perpendicular to the plane of rotation of the rod . Point `M` is the mid- point of the rod. Find the induced emf between `M` and `Q` if the potential between `P` and `Q` is `100 V`.

Explanation

`E_(MQ)+E_(PM)=E_(PQ)`
`E_(PM)=(B omega l^(2))/2=100`
`E_(MQ)+(B omega(l/2)^(2))/2=B omega^(2)/2 rArr E_(MQ)=3/8Bomegal^(2)=3/4xx100 V=75 V`