Question

Energy required to establish a current of $4A$ in a coil of self-inductance $L=200mH$ is

• A. $0.16J$
• B. $0.18J$
• C. $0.40J$
• D. $1.6J$

Answer 1

Answer: (D)

$1.6J$

Energy stored in a self-inductor, $E=\frac{1}{2}L{i}^2$
$=\frac{1}{2}\times 200\times {10}^{-3}[4{]}^2=1.6J$.