Proving Conservation of Momentum

AI Thread Summary
The discussion revolves around proving the conservation of momentum in the context of a bouncing ball experiment. The original poster seeks guidance on measuring the initial and impact velocities, questioning whether the floor's velocity can be assumed to be zero and how to address the mass in this scenario. A participant suggests that before proving momentum conservation, one should consider the principles of mass and energy conservation, which are foundational but not easily proven. The conversation highlights the challenges of setting up the experiment and the theoretical underpinnings necessary for the proof. Overall, the thread emphasizes the complexities involved in demonstrating conservation laws in physics.
WillTheBassis
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Hey guys I've a theory that my physics lecturer wants me to prove, basically I have to prove the conservation of momentum which is easy enough but it's in a specific situation which happens to be a bouncing ball.

So obviously I know relevant SUVAT equations and I know how to work out change in momentum in collisions and other situations and as well as working it out I have to set up and show the experiment.

So the initial velocity of the ball will be 0ms-1 and I can measure the mass of the ball quite easily I can also measure the impact velocity using light gates but I then run into a problem can I assume that the velocity of the floor is 0ms-1 and what do I do for the mass?

And help you guys could offer would be fantastic because I've hit a little bit of a rut with it. Thanking you all in advance. :)
 
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WillTheBasis,

It appears to me that before you can prove the conservation of momentum, you first have to prove the conservation of mass and the conservation of energy. As far as I know, their working mechanism is unknown, but they have never been found to be wrong. They are too basic to prove, unless you have something like a quantum theory explanation that defines what is happening.

Ratch
 
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