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Re: COLLISION



Damn, John Denker is right -- I forgot the work done on the air and the
resultant energy resident there as internal energy -- including sound (if
you will)

Jim

At 11:47 AM 26-11-99 -0700, you wrote:
> >Now, my concern is, where has the kinetic energy 'gone'?

Here is a prime case of how mis-use of the language and.or
mis-understanding of physics leads to faulty questions:

Energy doesn't "go" anywhere anytime -- ie "energy" does not move -- We
have discussed this ad nauseam (so why don't we learn?) Energy is a
_property_ of the various components of the system and can _only_ be
changed by doing work on those components. In this case the cars do work
on their respective coupling mechanisms and the two coupling mechanisms do
work on each other. And the various energy levels change. The _total_ of
each of the various component energies -- including the internal energies
of those components -- remains constant.

The problem here as I see it is that we want to use supposedly convenient
shorthand language and then we forget it is short hand.

Jim Green
mailto:JMGreen@sisna.com
http://users.sisna.com/jmgreen