Two pool balls of equall mass have a perfectly elastic headon collision.The fist ball is traveling at 2m/s and the second at 3m/s in the opposite direction.what are thier speeds immediately after impact? I'm lost on what equation to use here. Does the faster velocity transfer to the slower ball?

Question

Two pool balls of equall mass have a perfectly elastic headon collision.The fist ball is traveling at 2m/s and the second at 3m/s in the opposite direction.what are thier speeds immediately after impact?   I'm lost on what equation to use here. Does the faster velocity transfer to the slower ball?

drwls · Answer

In this situation, the balls exchange speeds and reverse direction. That keeps botht ehe kinetic energy and the linear momentum the same.
V1(final) = 3 m/s
V2(final) = 2 m/s

You set up the momentum and kinetic energy equations and solve them, and you would get this result. It only works for elastic collsions of equal masses.

Mark · Answer

Thanks