Question

Consider a metal ball of radius $r$ moving at a constant velocity $v$ in a uniform magnetic field of induction $\bar{B}$ . Assuming that the direction of velocity forms an angle ${}^{\prime }{\alpha }^{\prime }$ with the direction of $\bar{B}$ , the maximum potential difference between points on the ball is

• A. $r|\bar{B}||\bar{v}|\sin \alpha$
• B. $|\bar{B}||\bar{v}|\sin \alpha$
• C. $2r|\bar{B}||\bar{v}|\sin \alpha$
• D. $2r|\bar{B}||\bar{v}|\cos \alpha$

Answer 1

Answer: (C)

Given,
Radius of metal ball $=I$
Velocity $=V$
Angle between direction of velocity and magnetic field $(B)=\alpha$
We know that, $e=Blv\sin \alpha$
Here, $l=2re=2r|B\Vert v|\sin \alpha$