i have studied my lecture notes back to front and looked high and low for a clue how to do this question but i tried in a) constructing an expression for u and came up with DU= +TDS -PDV - FDL BAUT I COULD BE MILES OUT. could anyone help.(adsbygoogle = window.adsbygoogle || []).push({});

thanks

here it goes:

A piece of rubber of length L is subject to work by a hydrostatic pressure P and also

by a tensional force F.

a)Construct the expression for dU.

[Hint: the usual expression will have an extra term added to it corresponding

to the increment of work performed by F

b)Generate (i.e. invent new) thermodynamic potentials that have as proper vari-

ables (S; V; F); (S; P; F) and (T; P; F).

[Note: the potential R has (S; V; F) as proper variables if dR = xdS+ydV +zdF

where x; y; z are to be found.]

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# Thermodynamic potential question,help!

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