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Question #42738
The Question
A specialized liquid-electrolyte battery of EMF is connected across an external resistor . Due to pressure-induced viscosity changes, the average ion mobility in the electrolyte is inversely proportional to the hydrostatic pressure difference between the bottom and top of the electrolyte column. Consequently, the internal resistance of this battery depends on . When the battery is at rest on the ground, its internal resistance is . The entire setup is placed inside an elevator. If the elevator accelerates upwards with a constant acceleration , calculate the terminal voltage across the battery. (Assume the density of the electrolyte and the height of the column remain constant, and take ).
Options
- A.
- B.
- C.
- D.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Variable_Constraint
Develop pure symbolic logic skills by mastering algebraic constraints without relying on numerical data.
Concepts Behind This Question
Internal Resistance Variation|Apparent Weight in Accelerating Elevators|Work-Energy Theorem
Why This Question Is Tricky
Common Mistakes
This question tests the synthesis of non-inertial mechanics and electrodynamics.
Students often fall into the trap of treating a battery's internal resistance as a fixed constant, ignoring the mechanical environment of the liquid electrolyte.
By introducing a pressure-dependent mobility, the problem forces the application of the effective gravitational field () in an accelerating reference frame.
Common errors include ignoring the pseudo-force entirely (yielding 8 V), applying the pseudo-force in the wrong direction by subtracting acceleration (yielding 48/5 V), or incorrectly inverting the proportionality between resistance and pressure (yielding 9 V).
Quick Facts About This Question
Question Information
| Subject | Physics |
| Chapter | Current Electricity - Class 12 |
| Concept | Internal Resistance Variation |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |