1. Mechanical Foundations of the Generalized Second Law and the Irreversibility Principle.
- Author
-
Gujrati, Purushottam Das
- Subjects
ANALYTICAL mechanics ,STATIC equilibrium (Physics) ,THERMODYNAMICS ,ENTROPY ,TEMPERATURE - Abstract
We follow the Boltzmann-Clausius-Maxwell (BCM) proposal to establish the generalized second law (GSL) that is applicable to a system of any size, including a single particle system as our example establishes, and that supercedes the celebrated second law (SL) of increase of entropy of an isolated system. It is merely a consequence of the mechanical equilibrium (stable or unstable) principle (Mec-EQ-P) of analytical mechanics and the first law. We justify an irreversibility priciple that covers all processes, spontaneous or not, and having both positive and negative nonequilibrium temperatures temperatures T defined by (d Q / d S) E . Our novel approach to establish GSL/SL is the inverse of the one used in classical thermodynamics and clarifies the concept of spontaneous processes so that d S ≥ 0 for T > 0 and d S < 0 for T < 0 . Nonspontaneous processes such as creation of internal constraints are not covered by GSL/SL. Our demonstration establishes that Mec-EQ-P controls spontaneous processes, and that temperature (positive and negative) must be considered an integral part of dissipation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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