Question

The permanent magnetic moment of the atoms of a material is not zero. The material :

• A. must be paramagnetic
• B. must be diamagnetic
• C. must be ferromagnetic
• D. may be paramagnetic

Answer 1

Answer: (C)

must be ferromagnetic

Unlike paramagnetic materials, the atomic moments in ferromagnetic materials exhibit very strong interactions. These interactions are produced by electronic exchange forces and result in a parallel or antiparallel alignment of atomic moments.

This results in permanent non-zero magnetic moment of atoms in these materials.