Lecture
This lecture focuses on the relationship between entropy and the second principle of thermodynamics. The instructor begins by summarizing previous discussions on the Carnot cycle, emphasizing its reversible nature and the concept that the integral of delta-cuscurity over a cycle equals zero. This leads to the introduction of entropy as a state function, independent of the transformation path. The instructor clarifies the importance of calculating entropy using reversible transformations, even when dealing with irreversible processes. The lecture progresses to explore the calculation of entropy for perfect gases and introduces the Ts diagram, which relates temperature and entropy. The instructor illustrates how to calculate the yield of a Carnot cycle and discusses the implications of irreversible cycles. The lecture culminates in demonstrating the equivalence between the second principle of thermodynamics and entropy change, highlighting that for isolated systems, entropy must increase. The instructor reinforces these concepts through examples and exercises, ensuring a comprehensive understanding of the material.