Question

Question 6.8: Current in a circuit falls from 5.0 A to 0.0 A in 0.1 s. If an average emf of 200 V induced, give an estimate of the self-inductance of the circuit.

Class 12 - Physics - Electromagnetic Induction Electromagnetic Induction Page-230

Answer 1

Given,
Initial current $i_i$ = 5.0 A
Final current $i_2$ = 0.0 A
Time,t = 0.1 seconds
Average e.m.f = 200 V
Change in the current can be calculated as ,di  = 5.0A – 0.0A
di = 5 A

The self-conductance of the circuit is calculated using the formula,
$e=L\frac{di}{dt}\\L=\frac{e}{\frac{di}{dt}}$
Now, L = (200V ×0.1)/5 =4H