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Question #42614
The Question
A block of mass is attached to a fixed wall by a light spring of force constant . The block rests on a horizontal surface. The natural length of the spring is at . The surface is perfectly smooth for and rough for with a coefficient of kinetic friction . A stationary block of mass is placed exactly at the boundary . Block is pulled to and released from rest. When it reaches , it undergoes a perfectly inelastic collision with block , and they stick together. Find the maximum compression of the spring during the subsequent motion. (Take )
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
Energy Partitioning|Impulse-Momentum Theorem|Static Friction Threshold|Approximations
Why This Question Is Tricky
Common Mistakes
This problem tests the student's ability to correctly partition energy in a system interrupted by an inelastic 'stick' event (collision).
The primary trap is the erroneous application of the work-energy theorem over the entire interval from release to maximum compression.
Students often assume that the initial spring potential energy is simply dissipated by friction and converted into the final spring potential energy, completely missing the instantaneous, non-conservative kinetic energy loss during the perfectly inelastic collision at the boundary.
By forcing the student to use the impulse-momentum theorem to find the new state vector (velocity) post-collision, the problem transitions from a conservative SHM phase to a discontinuous energy decay phase.
Quick Facts About This Question
Question Information
| Subject | Physics |
| Chapter | Oscillations - Class 11 Part 2 |
| Concept | Energy Partitioning |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |