A small piece of metal wire is dragged across the gap between the pole pieces of a magnet in 10 s. The magnetic flux between the pole pieces is `8 xx 10^(-4)` Wb. Find the magnitude of induced e.m.f.

Options

A. `4xx10^(-3)` V
B. `8xx10^(-3)` V
C. `2xx10^(-3)V`
D. `6xx10^(-3)V`

Answer

C

Explanation

The charge of flux through the metal wire
`Deltaphi=8xx10^(-4) ` Wb
Time taken `Deltat=0.4` sec.
`therefore ` Induced emf, `e=(Deltaphi)/(Deltat)`
`=(8xx10^(-4))/(0.4)`
`=20xx10^(-3)V`