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

"A white pool ball (m1 = .3kg) moving at a speed of Vo1 = 3m/s collisdes head-on with a red pool ball (m2 = .4kg) initially moving at a speed of Vo2 = -2m/s. Neglecting friction and assuming the collision is perfectly elastic, what is the velocity of each ball after the collision?"

Underneath the question are two diagrams, a diagram labeled before (shows a white and red ball moving towards one another) and a diagram labeled after (shows the collision and the balls moving in opposite directions).

2. Relevant equations

p before = p after

3. The attempt at a solution

p before = p after

p1 + p2 = p1' + p2'

m1v1 + m2v2 = m1v1' + m2v2'

(.3kg)(3m/s) + (.4kg)(-2m/s) = (.3kg)v1' + (.4kg)v2'

.1 Ns = .3v1' + .4v2'

This is where i'm getting stuck...Since the balls have different masses, the velocities v1' and v2' will be different, but how can you make the two variables into one, and solve for the speeds?

Any help will be appreciated.

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# Momentum question

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