Posted by Dan on .
Ball 1, with a mass of 100g and traveling at 12 m/s , collides head on with ball 2, which has a mass of 340g and is initially at rest.
What are the final velocities of each ball if the collision is perfectly elastic?
What are the final velocities of each ball if the collision is perfectly elastic?

physics 
bobpursley,
Use conservation of momentum
m1v1=m1*v1' + m2v2'
solve that for v1'
Then use conservation energy.
1/2 m1*v1^2=1/2 m2*v1'^2 + 1/2 m2*v2'^2
put the v1' expression in that, and turn the algebra cranks, put it in quadratic form, and solve the quadratic equation.