QNEET-2024-Ph-163: NEET 2024 Physics - Class 12 NEET-2024-Ph-163 Solution: The magnetic potential energy when a magnetic bar of magnetic…

The magnetic potential energy U $U$ U of a magnetic dipole moment m _ $\vec{m}$ m in a magnetic field B _ $\vec{B}$ B is given by the formula: U = _ m _ _ B _ Here, the dot product m _ _ B _ $\vec{m} \cdot \vec{B}$ m _ B represents the scalar product of the vectors. When the magnetic moment m _ $\vec{m}$ m is placed perpendicular to the magnetic field B _ $\vec{B}$ B , the angle _ $\theta$ _ between these two vectors is 90 degrees. The dot product in this case can be written as: m _ _ B _ = m B cos _ _ Since _ = 90 _ $\theta = 90^\circ$ _ = 9 0 _ , we have cos _ 90 _ = 0 $\cos 90^\circ = 0$ cos 9 0 _ = 0 . Therefore, the magnetic potential energy U $U$ U becomes: U = _ m B cos _ 90 _ U = _ m B _ 0 U = 0 So, the magnetic potential energy when a magnetic bar of magnetic moment m _ $\vec{m}$ m is placed perpendicular to the magnetic field B _ $\vec{B}$ B is zero. The correct answer is: Option B "Zero".