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- elastic collision same mass 2.mp4

Credits

Author: Leong Tze Kwang, Lim Beng Choo

Document Brief: Title: "Tracker 2/5 Elastic Collision with Same Masses by Leongster"

This document explores a 2/5 elastic collision scenario where two objects of equal masses interact. The focus is on momentum conservation, energy distribution, and the implications of partially elastic collisions with a coefficient of restitution of 0.4.

Study Guide:

Objective: Investigate the dynamics of a 2/5 elastic collision involving two objects of equal masses, emphasizing momentum conservation and partial energy retention.

Key Concepts:

1. Elastic Collisions:

   • Collisions characterized by partial energy conservation, defined by the coefficient of restitution .

2. Conservation of Momentum:

   • The total momentum before and after the collision remains constant: , where is the equal mass of both objects.

3. Energy Distribution:

   • A portion of the kinetic energy remains in the system, with some converted to heat, sound, or deformation.

4. Coefficient of Restitution (e):

   • Defined as , indicating the ratio of relative velocities before and after the collision.

Experiment Overview:

• Setup: Two objects of identical mass collide on a frictionless surface. Their motion is analyzed using video tracking software such as Tracker.

• Procedure:

  • Record initial and final velocities of both objects.

  • Verify conservation of momentum and calculate the coefficient of restitution.

  • Determine the percentage of kinetic energy retained post-collision.

• Observation Points:

  • Changes in velocity due to collision.

  • Energy lost as a fraction of initial kinetic energy.

Questions to Consider:

1. Why do objects of the same mass exchange velocities in elastic collisions? (Ideal case )

   • Answer: Due to symmetry and conservation laws; however, with , velocities are only partially exchanged.

2. How is energy retention calculated?

   • Answer: By comparing initial and final kinetic energy: .

3. What role does the coefficient of restitution play?

   • Answer: It determines the elasticity of the collision, affecting the post-collision velocities and energy distribution.

Applications:

• Understanding energy dynamics in sports collisions, such as billiards.

• Exploring material properties affecting elasticity.

• Demonstrating momentum conservation in classroom experiments.

FAQ:

1. What is a 2/5 elastic collision? A collision where the coefficient of restitution is 0.4, meaning 40% of the relative velocity is retained post-collision.

2. Why use objects of equal mass? To simplify calculations and highlight the effects of elasticity on collision dynamics.

3. How does the coefficient of restitution affect energy loss? A lower value indicates greater energy loss, with more energy converted to non-kinetic forms.

4. Is momentum always conserved? Yes, momentum conservation holds regardless of the collision's elasticity.

5. What practical insights does this study provide? It aids in designing systems requiring controlled energy dissipation, like crash barriers or sports equipment.