Re: [Phys-l] heat +- impulse

["LaMontagne, Bob" <RLAMONT@providence.edu>]

> -----Original Message-----
> From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-
> bounces@carnot.physics.buffalo.edu] On Behalf Of John Denker
>
> There is one school of thought that says
>      -P dV _is_ the work and
>       T dS _is_ the heat
> in this context.  Just the other day I saw somebody write
>       dE = heat + work
> with this meaning.  

I don't really follow this way of formulating work - what if we have a
resistor immersed in water? Usually the rise in the internal energy of
the water is attributed to electrical "work" being done because a
temperature difference is not involved (since the resistor is basically
kept at the same temperature as the water bath).

> In my experience, instead of trying to quantify "heat", it has
> always been easier to quantify other things instead, usually
> energy and entropy.  

Do you have a macroscopic definition of S2 - S1 that does not involve
the heat associated with reversible processes connecting the end states?

Bob at PC