Physics - Magnetism Question with Solution | TestHub

Given:
Magnetising field, $H=5000$ A/m
Magnetic flux, $\Phi =4\times 10^{-5}$ Wb
Cross-sectional area, $A=0.4{\text{ cm}}^2=4\times 10^{-5}{\text{ m}}^2$

Magnetic induction $B$ is given by:
$B=\frac{\Phi }{A}$

Substituting the values:
$B=\frac{4\times 10^{-5}}{4\times 10^{-5}}=1$ T

Permeability $\mu$ of the rod is given by:
$\mu =\frac{B}{H}$

$\mu =\frac{1}{5000}=2\times 10^{-4}$ Wb/Am

Answer: $2\times 10^{-4}$