Magnetism And Matter

$\frac{\mu_0}{4 \pi} \frac{m}{r^3}$

$\frac{\mu_0}{8 \pi} \frac{m}{r^3}$

$\frac{\mu_0}{2 \pi} \frac{m}{r^3}$

$\frac{\mu_0}{\pi} \frac{m}{r^3}$