Question

The current in an inductor is changing at 110 A/s and the inductor emf is 45 V. What is the inductance of the inductor?

Answer 1

$$\Epsilon=L\dfrac{dI}{dt},$$ $$L=\dfrac{E}{\dfrac{dI}{dt}}=\dfrac{45\ V}{110\ \dfrac{A}{s}}=0.41\ H.$$