According to Curie's Law,
χ∝T1
Therefore, χ1T1=χ2T2
Also, χ=BM
So,
B1M1T1=B2M2T2
On substituting the values,
0.46×4=0.3M2×24
Therefore, M2=0.75Am−1
JEE Main 2020 — Physics Electromagnetism
A paramagnetic sample shows a net magnetisation of 6A/m when it is placed in an external magnetic field of 0.4T at a temperature of 4K. When the sample is placed in an external magnetic field of 0.3T at a temperature of 24K, then the magnetisation will be :
Held on 4 Sept 2020 · Verified 6 Jul 2026.
1A/m
4A/m
2.25A/m
0.75A/m
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