(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Deriving the head-on collision equation in terms of v2' and v1'

I think I'm having an algebra issue here, but how is the momentum equation (where v2=0):

m1(v1-v1')=m2v2'

combined with v1+v1'=v2'

to give:

v2' = v1 [ 2m1/(m1+m2)]

and

v1' = v1 [(m1-m2)/(m1+m2)]

I'm realizing this must be an elementary question since my book doesn't actually show how they derive those equations, but I'm not seeing it.

Help someone?

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# Homework Help: Deriving the head-on collision equation in terms of v2' and v1'

**Physics Forums | Science Articles, Homework Help, Discussion**