Question

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.

Answer 1

Initial current, I₁ = 5.0 A

Final current, I₂ = 0.0 A

Change in current,

Time taken for the change, t = 0.1 s

Average emf, e = 200 V

For self-inductance (L) of the coil, we have the relation for average emf as:

e = L

Hence, the self induction of the coil is 4 H.