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A magnetic needle is placed in a magnetic field that is not uniform. What will it experience?

1. No force and no torque
2. Torque only, not force
3. Force only, not torque
4. Both force and torque

Correct answer: Both force and torque

Solution

In a non-uniform magnetic field, the magnetic needle experiences a gradient in the magnetic field strength, which results in both a force acting on it and a torque that tends to align it with the field. The force arises from the variation in magnetic field strength across the needle, while the torque is due to the interaction of the needle's magnetic moment with the field.

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