Question

A soft ferromagnetic material is placed in an external magnetic field. The magnetic domains:

• A. decrease in size and changes orientation.
• B. may increase or decrease in size and change its orientation.
• C. increase in size but no change in orientation.
• D. have no relation with external magnetic field.

Answer 1

The correct option is B may increase or decrease in size and change its orientation.

Atoms of ferromagnetic material in unmagnetized state form domains inside the ferromagnetic material. These domains have large magnetic moment of atoms. In the absence of magnetic field, these domains have magnetic moment in different directions. But when the magnetic field is applied, domains aligned in the direction of the field, grow in size and those aligned in the direction opposite to the field reduce in size and also its orientation changes.