Question

A paramagnetic material has ${10}^{28}$${\text{atoms/m}}^3$. Its magnetic susceptibility at temperature $400\text{K}$ is $3\times {10}^{-4}$. Its susceptibility at $300\text{K}$ is $n\times {10}^{-5}$. The value of $n$ is

Answer 1

According to the Curie's law,

$\chi \propto \frac{1}{T}$

$\Rightarrow \frac{{\chi }_2}{{\chi }_1}=\frac{T_1}{T_2}$

Given,

$T_1=400\text{K};{\chi }_1=3\times {10}^{-4};T_2=300\text{K};{\chi }_2=n\times {10}^{-5}$

$\Rightarrow n\times {10}^{-5}=\frac{400}{300}\times (3\times {10}^{-4})$

$\therefore n=40$

Accepted answers:$40,40.040.00$