A magnetic field of `4 xx 10^(-4)"wbm"^(-2)` is acting at right angle to a coil of area
`8 xx 10^(2)"cm"^(2)` having 50 turns. The coil is removed from the field in 0.2 second, Calculate the
magnitude of emf induced in the coil.

Explanation

`B=4 xx 10^(-4)"wbm"^(-2)`
`A=8 xx 10^(2)"cm"^(2)=8 xx 10^(2) xx 10^(-4)m^(2)`
`A=8 xx 10^(-2)m^(2)`
Number of turns = N = 50
dt = 0.2 s
Induced emf = e = ?
`phi_(1)=NBA cos 0^(@)`
When magnetic field is at right angle to area of the coil
then angle between `overset rarr Band overset rarr A" is"" "0^(@)`
`phi_(1)=50 xx 4 xx 10^(-4) xx 8 xx 10^(-2)xx 1`
`=0.6 xx 10^(-3)"wb"`
When coil is removed from the magnetic field then
`phi_(2)=0`
`e=((phi_(2)-phi_(1)))/(dt)`
`= - ((0-1.6 xx 10^(-3)))/(0.2)`
`implies e = 8 xx 10^(-3)` volt