(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Two balls fall one above the other from height h= 5m. The bottom one has m= .1kg and the top one has m= .01kg. What will be the maximum elevation of the TOP ball after the balls hit the floor? Assume that collisions with the floor and between the balls are elastic.

2. Relevant equations

I tried this with: V1f= V1i* ((m1-m2)/(m1+m2)) + ((2m2)/(m1+m2))*V2i

V2f= V1i* ((2m1)/(m1+m2)) + ((m2-m1)/(m1+m2))*V2i

Then use: h= (1/2 m(V2)^2)/(mg)

3. The attempt at a solution

The issue is, the Vf is when the bottom ball has hit the floor and has changed directions and the m2 ball is still falling down... They collide and then the m2 ball changes direction.

I am so confused on what to do next. I appreciate any help possible! Thanks

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# Homework Help: Conservation of momentum

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