question_answer

A thin semicircular conducting ring of radius R is falling with its plane vertical in a horizontal magnetic induction\[\vec{B}\]. At the position MNQ the speed of the ring is v and the potential difference developed across the ring is:             

A)  zero

B)  \[B\pi v{{R}^{2}}/2\] and M is at higher potential

C)  \[\pi BRv\] and Q is at higher potential

D)  \[2RBv\] and Q is at higher potential