# Elastic collisions between unequal masses. Is it enough to know 'λ,v and m1/m2' ?

1. Jul 18, 2011

### simpatico

1. The problem statement, all variables and given/known data
if m1 and m2 (m1= m2, (vm1 = 4m/s)) collide at an angle λ (60°) we can fully predict oucome:
angles (60° and 30°) and speeds (2 and 3.46)

can we predict the outcome if we know that m1/m2 = 3/ 5 ?

Last edited: Jul 18, 2011
2. Jul 18, 2011

### cupid.callin

we can break the motion into X-Y axis.
for this let particle 1 is coming along +Y axis so particle 2 2ill be at 60 degree from it.

3. Jul 18, 2011

### simpatico

If I got it right: it is possible.!

(I know it makes things easier to consider m1 as moving on one axis.I prefer +X)

I asked because in all sites they said
'if you know what is v'1 or v'2 you can calc all other data'
while I knew that it is very easy and simple and quick to get all data
knowing only

v(m1) = 4 m/s (along the X-axis)
m1/ m2 = 3/5 ( m1), angle 60°

Thank you sir!

Last edited: Jul 19, 2011