Question

A solenoid of inductance $2H$ carries a current $2A$. What is the magnetic energy stored in a solenoid?

• A. $2J$
• B. $1J$
• C. $4J$
• D. $5J$

Answer 1

The correct option is B

$1J$

Step 1. Given Data,

Inductance $L=2H$,

Current $I=2A$,

Step 2. We have to calculate the Magnetic Energy stored,

We know that,

Magnetic energy stored $U=\frac{1}{2}L{I}^2$

$$\begin{gathered} \Rightarrow U=\frac{1}{2}\times 2\times {\left(1\right)}^2 \\ \Rightarrow U=1J \end{gathered}$$

Therefore magnetic energy stored, $U=1J$.

Hence, the correct option is $\text{'}B\text{'}$.