Discussion on the analogy between heat and electric conductions

Recently, the analogy between the processes of heating a solid body and charging an electric capacitor was deemed as heat-work analogy and argued that it was false and violated the second law of thermodynamics. It was claimed that the two processes were not analogous because the process of heating a solid body was classified as a purely thermal system, while that of charging an electric capacitor was classified as a purely mechanical system. In response, this note discusses the analogy between heat and electric conductions and that between heating a solid body and charging an electric capacitor. It is shown that the analogies have nothing to do with heat-work conversion, and never violate the second law of thermodynamics. The classification of charging an electric capacitor as a purely mechanical system is inappropriate. It is also shown that what we concern in the analogy analysis are the commonalities between the processes, rather than the differences. (C) 2018 Elsevier Ltd. All rights reserved.