Question

Assertion: The properties of paramagnetic and ferromagnetic substances are not affected by heating.
Reason: As temperature rises, the alignment of molecular magnets gradually decreases.

• A. Both A and R are true and R is the correct explanation of A
• B. Both A and R are true and R is not correct explanation of A
• C. A is true, but R is false
• D. A is false, but R is true

Answer 1

The correct option is D A is false, but R is true

Magnetic properties of para and ferromagnetic substances are affected by temperature.
$\chi =\frac{C{\mu }_0}{T}$
$\chi =\frac{C{\mu }_0}{T-T_c}$and
$T$ is absolute temperature and $T_c$ is curie's temperature for ferromagnetic substances and $C$ is Curie's constant.
According to curie's law,as temperature rises the alignment of atomic moment gradually decreases .