Question 75: Magnetism and Matter

Question

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:

Accepted Answer

According to curies law
$$\chi $$ $$ = {{C{B_{ext}}} \over T}$$
$$ \Rightarrow $$ $$6 = {{C 	imes 0.4} \over 4}$$
$$ \Rightarrow C = 60$$
$$ 	herefore $$ Case - II : $$\chi $$ $$ = {{60 	imes 0.3} \over {24}}$$ $$ = {{60 	imes 3} \over {240}} = {3 \over 4} = 0.75\,A/m$$

Answer

4 A/m

Answer

1 A/m

Answer

0.75 A/m

Answer

2.25 A/m

Magnetism and Matter

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:

Choose the correct answer: