Question

In the following figure, the magnet is moved towards the coil with a speed v and induced emf is e. If magnet and coil recede away from one another each moving with speed v, the induced emf in the coil will be

• A. e
• B. 2e
• C. e/2
• D. 4e

Answer 1

The correct option is B 2e

${\left(\frac{d\varphi }{dt}\right)}_{Infirstcase}=e$
${\left(\frac{d\varphi }{dt}\right)}_{relativevelocity2v}=2{\left(\frac{d\varphi }{dt}\right)}_{Icase}=2e$