An average emf of 20 V is induced in an inductor when the current in it is changed from `2.5 A` in one direction to the same value in the opposite direction in 0.1 s. Find the self inductance of the inductor.

Explanation

Here V=20 V, `
`di=i_2-i_1 =2.5-(0.5)=5A,`
`dt=0.1 s`
`V=L(di)/(dt)`
` implies 20=L(5/0.1)`
`implies 20 = Lxx50`
`impliesL=(20)/(50)=(4)/(10)=0.4 Henry.