Hidden Heat Reservoirs and Violations of the 2nd Law of Thermodynamics

AI Thread Summary
The discussion centers on the implications of the 2nd law of thermodynamics, specifically regarding the Clausius and Kelvin-Plank statements. A scenario is presented where two systems interact with the same thermal reservoirs, with one violating the Clausius statement while the other adheres to thermodynamic principles. The inquiry raises the possibility of redefining system boundaries to include a cold reservoir and a thermodynamically sound system, potentially leading to a net output of work that contradicts the Kelvin-Plank statement. The response suggests that the situation implies the existence of a hidden internal energy source within the system. This highlights the complexities of thermodynamic systems and the importance of proper boundary definitions in analyzing energy exchanges.
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I have a quick question concerning the 2nd law of thermodynamics. So my textbook uses an illustration to explain how the violation of the Clausius statement of the 2nd law implies a violation of the Kelvin-Plank. But while looking over the diagram I stated thinking about a certain situation. In the diagram two systems are shown communicating thermally with the same reservoirs. The on on the left is in violation of the Clausius statement while the one on the right is thermodynamicaly sound as its own system. But when you draw the boundary line around the two cycles and the cold reservoir, it violates the Kelvin-Plank statement, which is perfectly okay. However, what if a system boundary were drawn around the cycle to the right and the cold reservoir, making a system consisting of those two entities. It would seem that the system would be communication thermally with only one reservoir (the hot one) yet generate a net output of work, which violates the Kelvin-Plank statement. Any insight would be appreciated.
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I cannot see but it sounds like you have a system with a hidden internal energy source: the heat reservoir inside the box.
It still counts.
 
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