Solving Momentum and Kinetic Energy Relations

AI Thread Summary
The discussion focuses on a student's struggle to solve problems involving momentum and kinetic energy conservation. The student has specific values for two masses and their velocities but is unable to find the correct answers despite applying the relevant equations. They express frustration over repeated mistakes and seek guidance on how to approach the problem, particularly with two unknowns. The student has attempted substitution methods but remains confused about where they are going wrong. Assistance or alternative resources are requested to help clarify these concepts.
Garen
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Homework Statement


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Homework Equations


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[PLAIN]http://upload.wikimedia.org/math/7/7/4/7745116605c54295c6c3b696cea2d39f.png[/CENTER][/URL]

The Attempt at a Solution


I have gotten these problems wrong too many times. I know that I have to apply both the conservations of momentum and kinetic energy, but for some reason I can't come up with the right answer.

m1=21.3g v1=24.6cm/s
m2=11.6g v2=11.3cm/s

I don't know how to solve these relations with two unknowns. I've tried using substitution from the kinetic energy equation, but I still got it wrong for some reason. Any help for a desperate physics student?​
 
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Anyone know where I'm going wrong?
 
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No one? Really?
 
Maybe someone can refer me to another website to answer these questions?
 

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