Re: beyond the valley of the pseudowork (episode VI)

[Bob Sciamanda <trebor@VELOCITY.NET>]

JD writes:
"You can't separate kinetic energy into a center-of-mass piece distinct
from the other pieces; it's too nonlinear for that."

You can *always* write the KE of a system as the "CM KE" plus the KE
relative to the CM frame:

.5 MV^2  + SUM .5mi vi^2

where M=total system mass
V=CM speed
mi= individual mass
vi == speed of mi as measured from the CM frame.

Bob Sciamanda (W3NLV)
Physics, Edinboro Univ of PA (em)
trebor@velocity.net
http://www.velocity.net/~trebor
----- Original Message -----
From: "John S. Denker" <jsd@MONMOUTH.COM>
To: <PHYS-L@lists.nau.edu>
Sent: Friday, February 08, 2002 10:45 AM
Subject: beyond the valley of the pseudowork (episode VI)


> Hi --
>
> I've worked out a fairly complete description of why
> I think the so-called pseudowork has little to do with
> work, little to do with energy, and everything to do
> with momentum.  Momentum squared, to be precise.
>
> The writeup is at
>   http://www.monmouth.com/~jsd/physics/momentum-squared.htm