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Question #42827
The Question
A particle of mass and charge is constrained to move along a frictionless, non-conducting straight wire aligned with the -axis. The setup is permeated by an external electric field given by , where and are positive constants. The entire wire assembly is placed inside a rocket that accelerates along the positive -axis with a constant acceleration . In the reference frame of the rocket, the particle is released from rest at a position slightly displaced from its stable equilibrium point. Determine the position of the stable equilibrium point and the angular frequency of its small oscillations.
Options
- A.
- B.
- C.
- D.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Intuition_Breaker
Train your brain to resist "obvious" answers that are designed to deceive your intuition.
Concepts Behind This Question
Electric Field Line Geometry|Equilibrium Stability|Pseudo Force Directionality
Why This Question Is Tricky
Common Mistakes
This question tests the student's ability to analyze equilibrium and stability in a non-inertial reference frame.
A common trap is to either ignore the pseudo force entirely (leading to the purely electrostatic equilibrium at ) or to find the first root of the effective force equation () and blindly assume it is stable without performing the second derivative test on the effective potential.
Because the electric field magnitude decreases after , students relying purely on electrostatic intuition fail to realize that the constant pseudo force overtakes the weakening electric force, creating a stable potential well at where the net force gradient is negative.
Quick Facts About This Question
Question Information
| Subject | Physics |
| Chapter | Electric Charges and Fields - Class 12 |
| Concept | Electric Field Line Geometry |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |