Question

A $2cm$ long bar slides along metal rails at a speed of $1cm/s$ towards the right side. The magnetic field inside the bar and rails is $2T$, pointing out of the page. Find out the induced emf in the bar and rails?

• A. $2\times {10}^{-5}V$
• B. $2\times {10}^{-4}V$
• C. $4\times {10}^{-4}V$
• D. $2\times {10}^{-3}V$
• E. $4\times {10}^{-3}V$

Answer 1

Answer: (C)

$4\times {10}^{-4}V$

Given : $L=2cm=0.02$ m $v=1cm/s=0.01$ $m/s$ $B=2T$

$\therefore$ Induced emf $E=BvL=2\times 0.01\times 0.02=4\times {10}^{-4}$ $V$