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- collisionequalmassastroacademy.mp4

Credits

Author: video by Tim Peake, Robin Mobbs, Anu Ojha, Andy McMurry, and Sophie Allan , model by lookang
Contact: This email address is being protected from spambots. You need JavaScript enabled to view it.

Title: "Elastic Collision with Same Mass: A Tracker Analysis by Astro Academy"

This document explores the principles of elastic collisions using Tracker software. By analyzing collisions between objects of equal mass, it emphasizes the conservation laws of momentum and kinetic energy, offering practical insights into fundamental physics concepts.

Study Guide:

Objective:

• Understand elastic collisions through the motion analysis of objects with equal mass.
• Use Tracker to model and validate conservation laws in a controlled setup.

Key Concepts:

1. Elastic Collision:

   • A collision where no kinetic energy is lost; both momentum and kinetic energy are conserved.

2. Conservation of Momentum:

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

3. Conservation of Kinetic Energy:

   • The total kinetic energy of the system is conserved in an elastic collision.

Experiment Setup:

• Materials:

  • Two objects of identical mass.
  • A low-friction surface or a setup that minimizes external forces.
  • Tracker software for motion analysis.

• Procedure:

  1. Arrange the two objects, ensuring one is stationary.
  2. Propel the moving object towards the stationary one.
  3. Record the collision using a high-frame-rate camera.
  4. Import the video into Tracker.
  5. Mark the positions of both objects frame by frame to analyze their velocities before and after the collision.

Expected Observations:

• The moving object transfers its velocity to the stationary object.
• The total momentum and kinetic energy of the system remain unchanged.

Questions to Consider:

1. How is momentum conserved in the collision?

   • Answer: The momentum of the moving object is transferred to the stationary object, maintaining the total system momentum.

2. What happens to the velocities of the two objects?

   • Answer: The velocities are exchanged if the collision is perfectly elastic and both masses are equal.

3. How does Tracker verify energy conservation?

   • Answer: By calculating and comparing the total kinetic energy before and after the collision.

4. What assumptions are made in this model?

   • Answer: No energy is lost to friction, heat, or sound; the collision is perfectly elastic.

5. What real-world applications rely on elastic collisions?

   • Answer: Atomic and molecular interactions, sports physics, and certain types of material testing.

http://astroacademy.org.uk/resources/collisions/
http://www.opensourcephysics.org/items/detail.cfm?ID=14162

sources of errors

1. Tracker model builder has systemic error?
2. video is taken sideways with a slight perspective error that can result in the discrepant data
3. motion is not perfectly in x direction?

i need to analyse the video more in depth.

]

FAQ:

1. Why use objects of equal mass for this experiment?

   • To simplify the analysis and directly observe the velocity exchange principle.

2. What challenges might arise during data collection?

   • Friction and air resistance could introduce energy losses, making the collision less elastic.

3. Can this experiment be extended?

   • Yes, by introducing objects of different masses or analyzing inelastic collisions.

4. How does Tracker enhance learning in this experiment?

   • Tracker provides precise position and velocity data, allowing for detailed analysis of conservation laws.

5. What is the significance of elastic collisions in physics?

   • They exemplify fundamental conservation laws and are essential for understanding particle physics and material behaviors.