2003 AIPMT Magnetism and MatterDiamagnetism Easy Question 36 of 38 in Magnetism and Matter

Diamagnetic material in a magnetic field moves :

A from stronger to the weaker parts of the field
B from weaker to the stronger parts of the field
C perpendicular to the field
D in none of the above directions

The answer is A.

Solution

In a diamagnetic material, the external field induces a magnetisation opposite to the field (negative susceptibility).
In a non-uniform field, such a material is repelled by the stronger part of the field.
So a diamagnetic material moves from the stronger to the weaker parts of the field. (Paramagnetic and ferromagnetic materials move from weaker to stronger parts.)
Example: a diamagnetic liquid in a U-tube between magnet poles shows a fall in level in the arm placed in the strong field.

Concept Behaviour of diamagnetic substances

Magnetism and Matter in past papers

38 questions from this chapter have appeared across 21 exam years.