Graphic Representation of Quasi-Static Heat Exchange

• Roberto Rojas ^[2] ; Patricio Robles ^[1]
  1. [1] Pontificia Universidad Católica de Valparaíso

     Pontificia Universidad Católica de Valparaíso

     Valparaíso, Chile

     
  2. [2] Universidad Técnica Federico Santa María
• Localización: The Physics Teacher, ISSN 0031-921X, Vol. 56, Nº. 6, 2018, págs. 386-388
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Two bodies initially at different temperatures gathered into an isolated container exchange heat and reach an equilibrium state with a common final temperature. During the process, the system is out of equilibrium and its intermediate temperature is not well defined. By conceiving a quasi-static process with infinitesimal steps from the initial to the final state, a graphic representation of the intermediate temperatures is possible. We imagine an isolated container with the bodies in compartments separated by a wall, as shown in Fig. 1. If the conductivity of the wall is controlled, the heat exchange is made gradually through a sequence of very small portions of heat flowing from one body to the other. Each step is followed by a “dead time” in order to reach a momentary equilibrium state. These graphs are useful for students who need to analyze a phase change.