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

A 6 gram ball moving north at a rate of 3 m/s collides head on with an identical ball moving south at 2.0 m/s. The collision is elastic and the first ball moves south at 1 m/s. What is the velocity of the second ball?

2. Relevant equations

Law of conservation of momentum.

p=mv

3. The attempt at a solution

The question makes no sense to me. According to my solution guide, the other ball moves off at 2.0 m/s. But of the collision is elastic, then no energy should be wasted. So...2.0m/s worth of energy from the first ball is sucked into an abyss? Can anyone shed light on this?

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# Elastic Collision Problem

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