The length of side of a square loop is 4 m . This loop is placed in an uniform magnetic field of 2 . 5 T . Outside the loop, the magnetic field is zero and it is coming out side from magnetic field perpendicularly with velocity 2 m s . Find the value of induced emf in loop after one second.

Given, length of square=4m Magnetic field=2.5 T Initial flux, ϕ 1 = 2 . 5 × 4 × 4 ϕ 1 = 40 w e b e r After 1 second flux ϕ = 2 . 5 × 4 × 2 ϕ = 20 w e b e r Change in flux, ∆ ϕ = ϕ - ϕ 1 ∆ ϕ = - 20 ε = - ∆ ϕ ∆ t ε = - - 20 w e b e r 1 s e c ε = 20 v o l t s