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

5. A ball of mass M travelling at non-relativistic speed v elastically collides with a

stationary ball of mass m. Show that the maximum speed which the second ball can

have after the collision is

2M/(M+m) v

What is the minimum speed?

2. Relevant equations

3. The attempt at a solution

Ok well i know it's an elastic collision so I know that momentum and energy are conserved... So if i label the final velocities of the two masses v1 and v2 I can write;

Mv = Mv1+ mv2

and 1/2Mv^2 = 1/2 M v1^2 + 1/2 mv2^2

But how do i now work out the maximum and minimum possible values for v2?

I know that the minimum speed would imply they stick together, but then the collision would no longer be elastic..So is it asking for maximum and minimum speeds GIVEN the collision is elastic - in which case I don't understand why there should be a range of possible speeds? Surely the system is determined..? Confused :S

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# Homework Help: Quick Collision Problem

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