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

Options

A. `e`
B. `2e`
C. `e//2`
D. `4e`

Answer

B

Explanation

`((dvarphi)/(dt))_("in first case")=e`
`((dvarphi)/(dt))_("relative velocity" 2v)=2((dvarphi)/(dt))_(1 case)=2e`