Finding the velocities of two balls before they touch each other

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The discussion centers on calculating the velocities of two balls with different masses before they touch, given their initial distance and radii. The derived velocities are Vm=√(GM/R) for the lighter ball and V2m=0.5√(GM/R) for the heavier ball. Participants suggest using conservation of energy and momentum as a simpler approach to solve the problem. The original poster expresses uncertainty about applying these principles, thinking they might not be relevant. The conversation highlights the importance of conservation laws in solving physics problems effectively.
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Homework Statement


Two balls are given, the distance between their centers is 8R. Both have a radius of R.[/B]
One ball has a mass of 2m and the other has a mass of m.
The question is: What will be their velocities right before they touch each other
Answer: Vm=√(GM/R), V2m=0.5√(GM/R)

Homework Equations


F=GMm/r2

The Attempt at a Solution


I tried this equation:
9QEWW
https://imgur.com/a/9QEWW , but I don't know how to continue.
Thanks a lot![/B]
 
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Have you tried using conservation of energy and momentum?
 
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Chandra Prayaga said:
Have you tried using conservation of energy and momentum?
Ohhhh, I thought those questions don't include them, so this is the only way to solve it?
 
That is certainly a very simple way.
 

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