Ncert Exercises & Solutions

The value of the magnetic moment is zero in the case of antiferromagnetic substances because the domains -

I.	Get oriented in the direction of the applied magnetic field
II.	Get oriented opposite to the direction of the applied magnetic field
III.	Are oppositely oriented with respect to each other without the application of magnetic field
IV.	Cancel out each other’s magnetic moment

The correct choice among the given is -

1. (I, II)

2. (II, III)

3. (III, IV)

4. (I, IV)

Hint: Anti-ferromagnetism domains are oppositely oriented and cancel out each other's magnetic moment.

In the case of antiferromagnetic substances, the magnetic moment becomes zero because the domains are oppositely oriented

with respect to each other without the application of magnetic field which cancel out each other.