Title

Human Food Consumption: a Primer on Nonequilibrium Thermodynamics for College Physics

Document Type

Article

Publication Date

11-1-2008

Publication Title

European Journal of Physics

Abstract

Students often have great difficulties with applications of the energy principle, especially those from biology, although most introductory physics texts include a brief discussion of metabolism. We point out that many of these discussions are unsatisfactory, since they often fail to mention how biological systems are thermal systems in stationary nonequilibrium states. This has important implications: in particular, that energy input is in the form of work (i.e., change of potential energy) and that energy outflux is in the form of heat, which is necessary to maintain a stationary state. We focus on some key aspects of metabolism by using a mechanical analogue: energy input is the work done by the gravitational force on an object with mass m, and heat production is modelled as the energy dissipated by turbulent air flow around the object.

Original Citation

Zürcher, U. (2008). Human food consumption: a primer on nonequilibrium thermodynamics for college physics. European Journal of Physics, 29(6), 1183-1190.

DOI

10.1088/0143-0807/29/6/007

Volume

29

Issue

6