RT Journal Article T1 A simple example illustrating the application of thermodynamic extremum principles A1 Velasco Maíllo, Santiago A1 Fernández Pineda, Cristóbal AB A composite system consisting of two identical ideal gases separated by a movable, frictionless, diathermic piston is used to illustrate the application of different extremum principles in thermodynamics. The time evolution of the system from an initial constrained equilibrium state to the final equilibrium state is analysed by means of a very simple phenomenological model. PB IOP Publishing Ltd. SN 0143-0807 YR 2002 FD 2002-09 LK https://hdl.handle.net/20.500.14352/58863 UL https://hdl.handle.net/20.500.14352/58863 LA eng NO SV thanks the Comisión Interministerial de Ciencia y Tecnología (CICYT) of Spain for financial support under grant nº PB 98-0261 and the Junta de CyL-FSE of Spain for financial support under grant nº SA097/01. NO Comisión Interministerial de Ciencia y Tecnología (CICYT) of Spain NO Junta de CyL-FSE of Spain DS Docta Complutense RD 19 abr 2025