Question

A substance has magnetic permeability equal to $22\times {10}^{-4}\text{Tm/A}$. The value of magnetic susceptibility is

• A. $1750$
• B. $1751$
• C. $1752$
• D. $1749$

Answer 1

The correct option is D $1749$

The magnetic permeability of a substance is given as

$\mu ={\mu }_0{\mu }_r$

$\Rightarrow 22\times {10}^{-4}=4\pi \times {10}^{-7}\times {\mu }_r$

$\Rightarrow {\mu }_r=\frac{22\times {10}^{-4}}{4\times \frac{22}{7}\times {10}^{-7}}=\frac{7}{4}\times {10}^3=1750$

Relative permeability is related to magnetic susceptibility as:

${\mu }_r=1+\chi$

So, $\chi ={\mu }_r-1=1749$