2. Entropy = Measures the energy that has lost its capacity to do work

5. Example…

6. … of the First Type: (Motion with out energy being furnished) Perpetuum Mobile by Villard de Honnecourt (circa 1230). =

8. Example…

9. ...of the Second Type: (movement from only one heat source) Heat Work

10. Instead of… Heat (Hot) Work Cold

11. Joule’s Experiment

13. But, on the other hand, when transforming caloric energy to mechanical, contrary to the inverse process, part of the high temperature energy is always transformed in low temperature energy. Heat (High Temperature) Work Heat (Low Temperature)

14. An Assymetry in Nature is Found

18. Sadi Carnot (1876 – 1832)

19. Carnot’s Cycle (Represents an Ideal Engine) It’s a reversible process: Whereas working as a motor (I to IV) or as a refrigerator (IV to I), the processes are equivalent.

21. Carnot´s Engine Efficiency

23. Enters Rudolf Clausius (1822 – 1888)

25. … and determines that both transformations are equivalent Transformation of Energy, Q, into Work, between T 1 and T (T 1 greater than T) Transformation of Energy, Q between T 2 and T (T 2 greater than T),w/o performing Work i.e, by conduction.

29. … because procesess in Nature are not reversible, Entropy always increases… For a ireversible process

30. Enters Ludwig Boltzman (1844 – 1906)

33. Millon pounds metafor

34. A million pounds together can do more “Work” that the same quantity distributed among a million persons; in this last case, money has increased its “Entropy”.

35. The End Please look for references in the next slide