# Homework Help: Schroeder, Thermal Physics: impossible refrigerator?

1. Apr 4, 2010

### nonequilibrium

1. The problem statement, all variables and given/known data
Schroeder, Thermal Physics, p.129, Problem 4.12:
2. Relevant equations
COP = Qc/W

3. The attempt at a solution
I honestly have no idea why it shouldn't be possible. As for the COP, I get COP = cp/R * Pmin/$$\Delta$$P + cv/R * Vmax/$$\Delta$$V but not that it really matters, I think. It must a conceptual solution, I just have no clue...

All help appreciated,
Thank you