Calculating Impulse Without Mass: A Bouncing Ball Lab Dilemma

AI Thread Summary
The discussion centers on calculating kinetic energy (KE) and impulse for a bouncing ball without a given mass. The user successfully calculated KE by equating potential energy (PE) and KE at the midpoint of the bounce, using the height of 0.799 m to find PE as 3.92 J. However, confusion arises regarding how to derive impulse from this information, as impulse typically requires mass. It is noted that without mass or additional parameters, such as the ball's deformation upon impact, the impulse cannot be accurately determined. The conclusion emphasizes that the problem lacks sufficient data for a complete solution.
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Homework Statement


I am currently working on a lab that deals with a bouncing ball where I need to find the KE and impulse yet I have no mass given.


Homework Equations


PE=mgh
KE=1/2mv
p=mv

The Attempt at a Solution


I have calculated KE by first finding the PE in the middle of the bounce where they will be equal.
So half way from the highest point I calculated PE using PE=mgh. Then assumed KE was the exact same.

I am however confused as to how to calculate impulse since I have no mass, just a KE value.
 
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well what ARE you given?
 
The height of the first bounce was 0.799 m. Therefore half that distance is 0.3995 (Where KE and PE are equal). I then took this is used it in the PE equation. The mass of the ball is not changing however so I don't see that it's needed.
Therefore PE=mgh
PE=0.3995m x 9.8
PE=3.92
Therefore KE=3.92.

I don't know how to get impulse from this.
 
Ep isn't 3.92

if you take Ep=Ek at halfway point then:

mgh=(1/2)mv^2

therefore it is implied that

gh=(1/2)v^2

but it is not implied that Ep=gh...

I don't see what impulse you're looking for? If it's the impulse the ball has when it hits the ground it depends on how squishy the ball is.
 
If all you've been given is the height of the first bounce the question is not answerable.
 
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