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Question #42966
The Question
A rectangular container of length is placed along the -axis from to . It is filled with an incompressible diamagnetic fluid of density and magnetic susceptibility (where ). The system is permeated by a non-uniform magnetic field , where is a positive constant and is the unit vector in the vertically upward -direction. The container is given a constant horizontal acceleration (). In the steady state, the free surface of the fluid is observed to be perfectly horizontal at the edge . Assuming the fluid does not spill, what is the difference in height of the fluid surface between the edges and , given by ? (Here is the acceleration due to gravity and is the vacuum permeability).
Options
- A.
- B.
- C.
- D.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Multi-Concept_Bridge
Master problems that require linking physics and math concepts to solve complex competitive questions.
Concepts Behind This Question
Diamagnetic Property of Materials|Accelerated Frame Hydrostatics|Vector Cross-Products
Why This Question Is Tricky
Common Mistakes
This question tests the student's ability to synthesize fluid statics in an accelerated frame with the magnetic body force on a diamagnetic fluid.
A common trap is miscalculating the magnetic force density by either forgetting the factor of 1/2 in the formula or incorrectly using instead of , which leads to Option B.
Furthermore, students often fail to recognize that the 'horizontal' condition at is a boundary condition on the pressure gradient that fixes the unknown pseudo-force.
Ignoring the pseudo-force entirely leads to a sign-flipped, incorrect magnitude (Option C).
Quick Facts About This Question
Question Information
| Subject | Physics |
| Chapter | Magnetism and Matter - Class 12 |
| Concept | Diamagnetic Property of Materials |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |