Abstract
In thermodynamics, various sign conventions are used for energy transfers in the form of heat and work. Regardless of the sign convention introduced, thermodynamics texts subsequently abandon their established conventions in favor of magnitudes or absolute values. This article illustrates the importance of consistent use of a sign convention throughout a text and applies it to power-producing and power-consuming engineering devices. Additionally, using a selected sign convention, a substantive proof is presented showing why the ratio of energy added/rejected in the form of heat equals the ratio of the absolute temperatures of the energy source/sink, respectively.
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