Rankers Physics

Bar Magnet: Practice Problem & Solution

A current loop in a magnetic field : (2013)
Can be in equilibrium in two orientations, one stable while the other is unstable
Experiences a torque whether the field is uniform or non-uniform in all orientations
Can be in equilibrium in one orientation
Can be in equilibrium in two orientations, both the equilibrium states are unstable

Solution Explained:

To solve this problem, we apply the core principles of Bar Magnet. Understanding the underlying formula is key to arriving at the correct answer below:

A current loop in a uniform magnetic field experiences zero net force and can be in equilibrium when its magnetic moment is parallel (stable equilibrium) or antiparallel (unstable equilibrium) to the field.

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