280kg ball has elastic collision with 2nd ball which is initially at rest. Then 2nd ball moves with .5 velocity of 1st ball - what is mass of the 2nd ball? what percentage of KE gets transfered to 2nd ball(adsbygoogle = window.adsbygoogle || []).push({});

2. Relevant equations

I believe i use m1v1 + m2v2 = m1v1 +m2v2 (before & after), conservation of momemtum

then i think i would use 1/2mv2 + 1/2mv2 = 1/2mv2 + 1/2mv2 (energy before = energy after) conservation of energy

Maybe my algebra is just rusty, but i'm very confused.

3. The attempt at a solution

but i am having trouble just solving this the first equation. so if the m's cancel out i have v1 = v1 + v2 (the initial velocity of m2 = 0)

and then v2 = .5v1 so i have v1 = v1 + .5v1 is any of this correct? i'm confused

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Elastic Collision help

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