Question

If the magnetisation of a material is M and the magnetic field in the material is B, then the magnetic intensity is: ($\mu_0$ = permeability of free space)

• A. $\frac{B}{\mu_0}$
• B. $\frac{B - \mu_0 M}{\mu_0}$
• C. $\frac{\mu_0 M}{B}$
• D. $\frac{\mu_0 M}{B}$

Hint:

Use the relation $B = \mu_0 (H + M)$ to find the magnetic intensity $H$ in a material, where $M$ is the magnetisation and $\mu_0$ is the permeability of free space.

Answer 1

The Correct Option is B

The magnetic field $B$ in a material is related to the magnetic intensity $H$ and magnetisation $M$ by: $B = \mu_0 (H + M)$.
Rearranging for $H$: $H = \frac{B - \mu_0 M}{\mu_0}$.
Thus, the magnetic intensity is $\frac{B - \mu_0 M}{\mu_0}$.