A small cube of side 1 mm is placed at the centre of a circular loop of radius 10 cm carrying a current of 2 A. The magnetic energy stored inside the…

A small cube of side $\displaystyle 1$ mm is placed at the centre of a circular loop of radius $\displaystyle 10$ cm carrying a current of $\displaystyle 2$ A . The magnetic energy stored inside the cube is $\displaystyle \alpha \times 10^{-14} \mathrm{~J}$. The value of $\displaystyle \alpha$ is $\displaystyle \_\_\_\_$. ( $\displaystyle \mu_{\mathrm{o}}=4 \pi \times 10^{-7} \mathrm{Tm} / \mathrm{A}, \pi=3.14$ )