Question

At a temperature of ${30}^{o}C$, the susceptibility of a ferromagnetic material is found to be $\chi$. its susceptibility at ${333}^{o}C$ is

• A. $\chi$
• B. $0.5\chi$
• C. $2\chi$
• D. $11.1\chi$

Answer 1

The correct option is B $0.5\chi$

According to Curie's law, ${\chi }_m=\frac{{\mu }_{0}C}{T}$

where $C$ is Curie constant, $T=$temperature

$\therefore {\chi }_m\alpha \frac{1}{T}$

$\frac{{\chi }_{m_1}}{{\chi }_{m_2}}=\frac{T_2}{T_1}=\frac{273+333}{273+30}=\frac{606}{303}=2$

$\therefore {\chi }_{m_2}=\frac{{\chi }_{m_1}}{2}=0.5{\chi }_{m_1}=0.5\chi (\because {\chi }_{m_1}=\chi )$