Re: Energy as ability to do work

[Jim Green <JMGreen@SISNA.COM>]

> John, to expand the discussion; I'd agree with your point above; however,
> would you consider it wrong to view the center-of-mass kinetic energy of a
> rigid extensive object as being its ability to do work?

Joel & John -- yes there is always the work/energy theorem which would
agree with Joel, but I think that the advertised phrase is not helpful.

First, as John points out, it is not always correct.

And, the cart is before the horse - so to speak -- it is "work" which
changes the "energy" not the reverse.  One would not say that acceleration
is the ability to produce force would one?  Work is the "cause" and change
in energy is the "result".



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