In terms of the thermodynamic identity:(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

dU = {\tau}d{\sigma} - pdV

[/tex]

the term for the work done on the system ([itex]-pdV[/itex]) must be positive if there is a compression, in which case dV would be negative, correct? If one wanted to write the identity in terms of the work done *by* the system, you would simply switch the sign.

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