http://sites.science.oregonstate.edu/portfolioswiki/ 2020-01-26T23:02:41-08:00 http://sites.science.oregonstate.edu/portfolioswiki/ http://sites.science.oregonstate.edu/portfolioswiki/lib/images/favicon.ico text/html 2016-06-10T15:13:32-08:00 http://sites.science.oregonstate.edu/portfolioswiki/whitepapers:pdm:start?rev=1465596812 The Partial Derivative Machine [The Partial Derivative Machine in all its glory.] We have designed an apparatus, which we have called a Partial Derivative Machine (PDM), that serves as a mechanical analogue of a thermodynamic system. Using this device, students have a tangible way to wrestle with issues related to partial derivatives and thermodynamics, such as which variables are held fixed, how many variables are independent, and how energy can be added to a system.