A small piece of wire is passed through the gap between the poles of a magnet in 0.1 sec. An e.m.f. of `4 xx 10^(​–8)` ​volts is induced in the wire. The magnetic flux between the poles (in weber) is:

Options

A. 10
B. `4xx10^(-9)`
C. `4xx10^(-2)`
D. `0.1`

Answer

B

Explanation

`v=l/(Deltat)`
e=Bav
`e=(B)(a)(l/(Deltat))`
`e=phi(l/(Deltat))`