Question

If a current of $5A$ in a coil of self inductance $2mH$ is cut-off in time $0.1s,$ the induced emf in the coil is

• A. 0.1 V
• B. 0.01 V
• C. 0.2 V
• D. 0.02 V

Answer 1

Answer: (A)

Induced emf $e=L\frac{di}{dt}=2\times 10^{-3}\times \frac{5}{0.1}$
$=0.1V$