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Elastic collisions

With elastic collisions, energy is also conserved. The only really good examples of elastic collisions involve atomic particles and the like. But you can get pretty close in ordinary life, say with pool balls or a superball.

Lets say we start with two balls with masses tex2html_wrap_inline1069 and tex2html_wrap_inline1071 having initial velocities tex2html_wrap_inline1375 and tex2html_wrap_inline1377 respectively. They collide and end up with velocities tex2html_wrap_inline1379 and tex2html_wrap_inline1381

  figure367

Before:
The total momentum tex2html_wrap_inline1383 . The total energy is tex2html_wrap_inline1385 .
After:
The total momentum tex2html_wrap_inline1387 . The total energy is tex2html_wrap_inline1389 .

Equating the total momentum and energy before and after the collision

  eqnarray383

Let's try to analyze the collision of two balls in one dimension.





Joshua Deutsch
Fri Jan 17 12:19:41 PST 1997