Reversible Adiabatic or Isentropic Volume Changes

To plot the course of this expansion on a P-V diagram we need to have a function for (dP/dV)s and be able to integrate it. This function is (using Table 2.1) 

To calculate the work done during the isentropic expansion between these two points, we calculate the change in apparent internal energy, AU, between the two points, which is 

This is less than half the work that an ideal gas would do under the same conditions. 

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