Question

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.

Answer 1

Here $V=20V,$

$di=i_2-i_1=2.5=\left(0.5\right)=5A,$

$dt=0.1s$

$V=L\frac{di}{dt}$

$\Rightarrow 20=L\left(\frac{5}{0.1}\right)$

$\Rightarrow 20=L\times 50$

$\Rightarrow L=\frac{20}{50}=\frac{4}{10}=0.4$ Henry.