Question

The magnetic induction in vacuum at a plane surface of a uniform isotropic magnetic is equal to $B$, the vector $B$ forming an angle $\alpha$ with the normal of the surface. The permeability of the magnetic is equal to $\mu$. Find the magnitude of the magnetic induction $B^{\prime }$ in the magnetic in the vicinity of its surface.

Answer 1

${B^{\prime }}_n=B\cos \alpha$,
${H^{\prime }}_t=\frac{1}{{\mu }_0}\sin \alpha$,
${B^{\prime }}_t=\mu B\sin \alpha$
so, $B^{\prime }=B\sqrt{{\mu }^2{\sin }^2\alpha +{\cos }^2\alpha }$