Q6.8  Current in a circuit falls from $5.0A$ to $0.0A$  in $0.1s$ . If an average emf  of $200V$  induced, give an estimate of the self-inductance of the circuit.

Given

Initial current $I_{initial}=5A$

Final current $I_{final}=0A$

Change in time $I_{final}=\Delta t=0.1s$

Average emf $e=200V$

Now,

As we know, in an inductor

$e=L\frac{di}{dt}=L\frac{\Delta I}{\Delta t}=L\frac{I_{final}-I_{initial}}{\Delta t}$

$L= \frac{e\Delta t}{I_{final}-I_{initial}}=\frac{200*0.1}{5-0}=4H$

Hence self-inductance of the circuit is 4H.

Exams
Articles
Questions