Question

The relation connecting magnetic susceptibility $ \chi_{m} $ and relative permeability $ \mu _{r} $ is

• A. $ \chi _{m}=\mu_{r}+1 $
• B. $ \chi _{m}=\mu _{r}-1 $
• C. $ \chi _{m}=\frac{1}{\mu _{r}} $
• D. $ \chi _{m}=3(1+\mu _{r}) $

Answer 1

Answer: (B)

Total magnetic flux density $B$ in a material is the sum of magnetic flux density in vacuum $ B_{0} $
produced by magnetising force and magnetic flux density due to magnetisation of material
$ B_{m}$ ie, $ B=B_{0}+B_{m} $
$ \Rightarrow $ $ B=\mu _{0}H+\mu_{0}I=\mu _{0}(H+I) $
$ =\mu _{0}H(1+\chi _{m}) $
Also $ \mu _{r}=(1+\chi _{m}) $