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Question
A ferromagnetic material is placed in an external magnetic field. The magnetic domains ______________ .
Options
increase in size
decrease in size
may increase or decrease in size
have no relation with the field
Solution
may increase or decrease in size
Atoms of ferromagnetic material in unmagnetised state form domains inside the ferromagnetic material. These domains have large magnetic moments due to the 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.
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