A billiard ball traveling at 4.0 m/s has an elastic head-on collision with a billiard ball of equal mass that is initially at rest. The first ball is at rest after the collision. What is the speed of the second ball after the collision?(adsbygoogle = window.adsbygoogle || []).push({});

What equation should i use? Please post.

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# Homework Help: What is the speed of the second ball after the collision?

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