A paramagnetic sample shows a net magnetisation of 6 A/m when it is placed in an external magnetic field of 0.4 T at a temperature of 4 K. When the sample is placed in an external magnetic field of 0.3 T at a temperature of 24 K, then the magnetisation will be:
Solution
According to curies law
<br><br>$\chi$ $= {{C{B_{ext}}} \over T}$<br><br>$\Rightarrow$ $6 = {{C \times 0.4} \over 4}$<br><br>$\Rightarrow C = 60$<br><br>$\therefore$ Case - II : $\chi$ $= {{60 \times 0.3} \over {24}}$ $= {{60 \times 3} \over {240}} = {3 \over 4} = 0.75\,A/m$
About this question
Subject: Physics · Chapter: Magnetism · Topic: Bar Magnet and Magnetic Field
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