A current of 5 A is flowing in a 20 mH inductor. The energy stored in the magnetic field of this inductor is
A)1 J.
B)0.25 J.
C)0.50 J.
D)0.
E)dependent upon the resistance of the inductor.

Question

Quizplus · Accepted Answer

The energy stored in an inductor is given by the formula $ \frac{1}{2} L I^2 $. Substituting the given values, $ L = 20 \, \text{mH} = 0.02 \, \text{H} $ and $ I = 5 \, \text{A} $, the energy is $ \frac{1}{2} \times 0.02 \times 5^2 = 0.25 \, \text{J} $.

A Current of 5 a Is Flowing in a 20