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- elastic different mass 2.mp4
- Conservation of momentum_ws_video_student.docx

Credits

Author: Leong Tze Kwang, Lim Beng Choo

Document Brief: Title: "Tracker 1/5 Elastic Collision with Different Masses by Leongster"

This document analyzes a 1/5 elastic collision scenario where two objects of different masses interact. The focus is on the principles of momentum conservation, energy transfer, and the characteristics of partially elastic collisions.

Study Guide:

Objective: Investigate the dynamics of a 1/5 elastic collision involving objects of unequal masses, examining momentum conservation and the coefficient of restitution.

Key Concepts:

1. Elastic Collisions:

   • Collisions where some kinetic energy is conserved, characterized by the coefficient of restitution . For a 1/5 elastic collision, .

2. Conservation of Momentum:

   • The total momentum before and after the collision remains constant: .

3. Energy Transfer:

   • A portion of the kinetic energy is converted to other forms, such as heat or deformation.

4. Coefficient of Restitution (e):

   • Defined as , where represents velocity, and subscripts and denote initial and final states, respectively.

Experiment Overview:

• Setup: Two objects of differing masses are allowed to collide on a frictionless surface. The motion is tracked using video analysis tools like Tracker.

• Procedure:

  • Record initial and final velocities of both objects.

  • Calculate momentum before and after collision to verify conservation.

  • Compute the coefficient of restitution and analyze the energy loss.

• Observation Points:

  • Change in velocity of each mass.

  • Percentage of kinetic energy conserved.

Questions to Consider:

1. What determines the post-collision velocities of the two objects?

   • Answer: The relative masses, initial velocities, and the coefficient of restitution .

2. How is momentum conservation verified?

   • Answer: By showing that the sum of momenta before the collision equals the sum after the collision.

3. What factors influence the amount of energy lost?

   • Answer: The coefficient of restitution and material properties of the colliding objects.

Applications:

• Understanding real-world collisions, such as vehicle impacts.

• Designing materials and systems to manage energy dissipation.

• Teaching momentum and energy principles in physics.

FAQ:

1. What is a 1/5 elastic collision? A collision where the coefficient of restitution is 0.2, indicating partial elasticity and significant energy loss.

2. Why use objects of different masses? This setup highlights the effect of mass disparity on velocity changes and energy transfer.

3. How is energy loss calculated? By comparing the total kinetic energy before and after the collision: .

4. What does the coefficient of restitution signify? It measures the elasticity of the collision, with 1 being perfectly elastic and 0 being perfectly inelastic.

5. Can this model be applied to real-world scenarios? Yes, it helps in understanding collisions in sports, vehicle safety, and material testing.