Question

A paramagnetic material has $10^{28} \, atoms \, m^{- 3}$ . Its magnetic susceptibility at temperature $350 \, K$ is $2.8\times 10^{- 4}$ . Its susceptibility at $300 \, K$ is

• A. $3.726\times 10^{- 4}$
• B. $2.672\times 10^{- 4}$
• C. $3.267\times 10^{- 4}$
• D. $3.672\times 10^{- 4}$

Answer 1

Answer: (C)

From Curie's law
$\chi \propto \frac{1}{T}$
$\frac{\chi_{2}}{\chi_{1}}=\frac{T_{1}}{T_{2}}$
$\chi_{2}=\chi_{1}\cdot \frac{T_{1}}{T_{2}}=\text{2.8}\times 10^{- 4}\times \frac{350}{300}=\text{3.267}\times 10^{- 4}$