A 1.1-H solenoid is fed by a direct current of 25A. Then the power source is disconnected.Then the two ends of the solenoid are directly connected by a wire.How many Joules of heat are produced if all of the energy that was stored goes into heating the wire?
A)1.4 J
B)344 J
C)0 J
D)2.6 kJ

Question

Quizplus · Accepted Answer

The energy stored in an inductor (solenoid in this case) is given by the formula $E = \frac{1}{2}LI^2$, where $L$ is the inductance in henries and $I$ is the current in amperes. Substituting the given values, $E = \frac{1}{2} \times 1.1 \times 25^2 = 343.75$ Joules. Since all of this energy goes into heating the wire, the correct answer is 344 J, rounding to the nearest whole number.

A 11-H Solenoid Is Fed by a Direct Current of 25A