Question

A small piece of metal of volume $10cm$ has a uniform magnetic field $4$ t inside it. The magnetic energy stored in the metal B is

Answer 1

We know that, magnetic energy stored in a metal is, $U_B=\frac{B^2}{2{\mu }_o}$

Here, ${\mu }_o=4\pi \times {10}^{-7}N/A^2$

$\therefore U_B=\frac{4^2}{2\times 4\pi \times {10}^{-7}}$

= $6.37\times {10}^{6}J$