Question

Write the properties of diamagnetic, paramagnetic, and ferromagnetic materials.

Hint:

Ferromagnetism is responsible for most permanent magnets used in everyday life.

Answer 1

Step 1: Diamagnetic materials are characterized by having all their electrons paired, resulting in no permanent magnetic moment. When an external magnetic field is applied, these materials induce a magnetic field in the opposite direction due to changes in the orbital motion of electrons. This causes a very weak repulsion from the applied magnetic field.
Step 2: Paramagnetic materials possess one or more unpaired electrons, giving rise to permanent but randomly oriented magnetic moments. When subjected to an external magnetic field, these magnetic moments tend to align weakly in the direction of the field, resulting in a slight attraction towards the magnetic source. However, this alignment is usually lost once the external field is removed.
Step 3: Ferromagnetic materials contain magnetic domains, which are regions where groups of atomic magnetic moments are strongly aligned in the same direction even without an external field. Upon applying a magnetic field, these domains align more uniformly, causing a strong attraction. Ferromagnetic materials can retain this alignment, exhibiting permanent magnetism, and are widely used in the fabrication of permanent magnets and magnetic storage devices.