A  paramagnetic sample shown a net magnetisation of  8 A/m. When placed in an external magnetic field of 0.6T at a temperature of 4K. When placed in an external magnetic field of  0.3T  at a 16K ,  then find magnetisation ( in  A/m) at this temperature

From Curie’s Law we can deduce a formula for the relation between magnetic field Induction, temperature and magnetisation

                                                  $\begin{array}{l}I \propto \frac{B}{T}\\ \Rightarrow \frac{I_2}{I_1}=\frac{B_2}{B_1}\times \frac{T_1}{T_2}\\ Put I_1=8A/m , B_1=0.6 , T_1 = 4K , B_2=0.3T\\ T_2=16K\\ I_2=?\\ \therefore \frac{I_2}{8}=\frac{0.3}{0.6}\times \frac{4}{16}\\ \Rightarrow I_2=1A/m\end{array}$