Question

A conducting rod of length $2\ell $ is rotating with constant angular speed $\omega $ about its perpendicular bisector. A uniform magnetic field $\overset{ \rightarrow }{B}$ exists parallel to the axis of rotation.The emf induced between two ends of the rod is:

• A. $B\omega \ell ^{2}$
• B. $\frac{1}{2}B\omega \ell ^{2}$
• C. $\frac{1}{8}B\omega \ell ^{2}$
• D. Zero

Answer 1

Answer: (D)

$V_{x}+\frac{B \omega l^{2}}{4}-\frac{B \omega l^{2}}{4}-V_{y}=0$
$\Rightarrow V_{x}-V_{y}=0$