Re: First Law

[brian whatcott <inet@INTELLISYS.NET>]

At 12:02 3/6/99 -0700, you wrote:
> I would like to update my First Law web page.  There I consider the effects
> of various actions on a system: piston, paddle wheel, propane torch, hot
> plate, etc.  I don't think I have included sufficient actions:  all except
> the hot plate and the piston are not reversible -- unless one invokes some
> magic.
>
> Can list members suggest a macroscopic (read mechanical) action beside the
> piston which one could realistically consider reversible??? ...

> Jim Green

I suppose I need to imagine some mechanism which can slowly exchange
pressure and volume without the agency of a piston, and without stirring up
bulk chaotic motion.
  One thinks of a u tube with a closed end and a liquid in the u bend.
Or a drinking bird. But that is nothing less than a piston.
   So I have to think big - very big.
  Take a planet and melt its icebergs - the water vapor augments the volume;
chill it and the atmospheric volume falls?

 No, this is not quite what is wanted, I fear.

Brian

brian whatcott <inet@intellisys.net>
Altus OK