A square copper coil of each side 8 cm consists of 100 turns. The coil is initially in vertical plane, such that the plane of the coil is normal to uniform magnetic field of induction 0.4 `Wb m^(-2)`. The coil is turned throuugh `180^(@)` about a horzontal axis in 0.2 s. Find the induced e.m.f.

Explanation

Here, `A = 8 xx 8 = 64 cm^(2) = 64 xx 10^(-4) m^(2)`
`N = 100`
`theta_(1) = 0^(@), B = 0.4 Wb m^(-2), theta_(2) = 180^(@), t = 0.2 s`
`e = (- (phi_(2) = phi_(1)))/(t) = (- NAB (cos theta_(2) - cos theta_(1)))/(t)`
`= (- 100 xx 64 xx 10^(-4) xx 0.4 (cos 180^(@) - cos0^(@)))/(0.2)`
`= 2.56 V`