Correction: sign convention for work done

Hi all,

There is another correction. There is an error in the earlier post about the sign convention used for calculating work done.

The sign convention for work done, as adopted in class and in the book (pg. 9) is expressed as:
dW = - P dV

For example, for an ideal gas, going from V1 to V2 in a mechanically reversible isothermal process,
W = -RT ln(V2/V1) = RT ln(V1/V2)
W = -RT ln(P1/P2) = RT ln(P2/P1)

Hence a compression process results in positive work, and expansion process results in negative work.

Sorry for the error in the earlier post. The solutions to HW 4 as posted use the correct sign convention, so you can refer to those and you should be OK.

thanks
badri