Re: What Flows?

[jmclean@chem.ucsd.edu]

Leigh Palmer says:
> It seems to me that "thermal energy" must be connected somehow to heat.
> To illustrate the problems with this arbitrary partition of energy let me
> propose some questions and ask some more questions about the questions.
>
> 1. Take a quantity of gas in an insulated cylinder and allow it to expand
> a factor of two. It will cool off, of course. By how much has its thermal
> energy changed in this process?

What if instead you consider "thermal energy" to be connected somehow to
temperature?  That actually seems to me to be the more direct connection;
'heat' only gets into the question by way of the colloquial usage where
heat=temperature.

Now does it seem strange that the expanding gas looses "thermal energy"
even with no heat tansfer?

Note: Not that I prefer "thermal energy" over "internal energy"
necessarily, but I have to admit that it seems more descriptive.

-- 
--James McLean
jmclean@chem.ucsd.edu
post doc
UCSD