Question

A magnetic needle is kept in a non-uniform magnetic field. It experiences:

• A. neither a force nor a torque
• B. a torque but not a force
• C. a force but not a torque
• D. a force and a torque

Hint:

In a non-uniform magnetic field, the imbalance in forces on the poles of a magnetic dipole generates both a net force and a torque. The torque aligns the dipole with the field lines.

Answer 1

The Correct Option is D

In a non-uniform magnetic field, a magnetic needle is subjected to a net force and a torque.
The magnetic field exerts varying forces on the needle's poles due to its non-uniformity, creating an imbalance.
This imbalance leads to a net force on the needle.
Concurrently, these differing forces generate a torque that rotates the needle to align with the magnetic field lines.
Final Answer: \[\boxed{\text{a force and a torque}}\]