One of entropy’s puzzling aspects is its dimensions of energy/temperature. A review of thermodynamics and statistical mechanics leads to six conclusions: (1) Entropy’s dimensions are linked to the definition of the Kelvin temperature scale. (2) Entropy can be defined to be dimensionless when temperature T is defined as an energy (dubbed tempergy). (3) Dimensionless entropy per particle typically is between 0 and ∼80. Its value facilitates comparisons among materials and estimates of the number of accessible states. (4) Using dimensionless entropy and tempergy, Boltzmann’s constant k is unnecessary. (5) Tempergy, kT, does not generally represent a stored system energy. (6) When the (extensive) heat capacity tempergy is the energy transfer required to increase the dimensionless entropy by unity.
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December 1999
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December 01 1999
What if entropy were dimensionless?
Harvey S. Leff
Harvey S. Leff
Physics Department, California State Polytechnic University, Pomona, 3801 West Temple Avenue, Pomona, California 91768
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Am. J. Phys. 67, 1114–1122 (1999)
Article history
Received:
July 23 1998
Accepted:
March 02 1999
Citation
Harvey S. Leff; What if entropy were dimensionless?. Am. J. Phys. 1 December 1999; 67 (12): 1114–1122. https://doi.org/10.1119/1.19094
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