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

A mass m with initial velocity v0 collides head on with a mass 2m initially at rest. What is the final velocity of the smaller mass, as a ratio to v0?

What is the final velocity of the larger mass, as a ratio to v0?

2. Relevant equations

Pi=Pf

KE=.5mv^2

3. The attempt at a solution

for part a I am confused as to what I am doing wrong:

mv_{o}=mv_{1}+2mv_{2}

it wants to find v1 in terms of vo so:

v_{2}=.5(v_{o}+v_{1})

then plug into KE equation:

v_{o}^{2}=v_{1}^{2}+.25(v_{1}^{2}+v_{o}^{2})

and simplify to get

(3/4)v_{o}^{2}=(5/4)v_{1}^{2}

then v_{1}=(3/5)^{1/2}v_{o}

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# Two masses colliding

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