[Phys-L] Re: collision question

[Scott Goelzer <s.goelzer@COMCAST.NET>]

On Feb 18, 2005, at 9:30 AM, Bob Sciamanda wrote:

> Two electrons flying by (while repelling) each other, generate E/M
> radiation
> fields which carry away momentum/energy.  This momentum/energy is lost
> to
> the two particle system and is ultimately absorbed and thermalized by
> the
> lab walls and/or other objects.  Why can I not say that
> momentum/energy has
> been dissipated by the two particle system?

I'll give it a shot.
Initially there was no momentum , then as the electrons pushed away
from each other there is still zero total momentum since p is a vector.
If the room is included in the system, then after the electrons
interact with the room, the total momentum remains zero and the CM is
not changed. Individual momentums did not dissipate , they cancelled.

Scott



**********************************
Scott Goelzer
Physics Teacher
Coe-Brown Northwood Academy
Northwood NH 03261
603-942-5531e218
sgoelzer@coebrownacademy.com
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