Potential Energy of an Elastic System

Keywords: Thermodynamics, Partial Derivatives, Partial Derivative Machine, Interlude, Potential Energy

Highlights of the activity

This integrated lab activity is designed to provide upper-division undergraduate students with the means to experimentally determine state variables and the potential energy of an elastic system (PDM).
Students use the Partial Derivative Machine (PDM) to verify experimentally that the forces and dimensions of their system are state variables as well as measure the relationships between these quantities to compute the potential energy of their system.
The whole class discussion focuses on how many independent variables there are in the PDM, and which variables the potential energy is a function of.

Reasons to spend class time on the activity

This activity occurs during the “Interlude”, a brief course on the basic mathematics used in the “Energy and Entropy” Paradigm. This course primarily focuses on an introduction to partial derivatives and total differentials. We would like our students to have an understanding of how to measure partial derivatives and their relation to real physical quantities. This lab exercise uses the Partial Derivative Machine (PDM) to experimentally verify the state properties of an elastic system (i.e. the PDM). Using the PDM, the students measure the relationships between the state variables in such a way that they may determine the potential energy of the system.

For a description of the Partial Derivative Machine visit this page.