Re: [Phys-l] workable versus unworkable energy

[Brian Whatcott <betwys1@sbcglobal.net>]

At 11:48 AM 1/11/2007,  Rick T., you wrote:

> ....I could choose to look at the fact that
> the average, translational kinetic energy per molecule has increased.

 I acknowledge John D.'s riposte about the energy mode
of a molecule in a solid being largely vibratory or rotary rather than
translational, I found Rick's insight below, about
thermal to kinetic transfers fresh and helpful.

> the great technological advance that lead to the
> industrial revolution was when we figured how to convert _some_ thermalized
> (thermal) energy into useful work.  Prior to the steam engine we only knew
> how to transfer kinetic and potential energy into thermal energy, or thermal
> energy from one object to another.  The ability to go from thermal to
> kinetic is a defining point in human development. ....
>
> Rick

No matter how often I discount minor temperature differences
 as being inaccessible to providing useful work, I do recall that
"drinking bird" thermal engines, and a variety of Stirling engines
can turn very small  delta T's to advantage.




Brian Whatcott    Altus OK    Eureka!