This article describes a unit on oscillations, determinism and chaos developed for calculus-based introductory physics students as part of the laboratory-centered Workshop Physics curriculum. Students begin by observing the motion of a simple pendulum with a paper clip bob with and without magnets in its vicinity. This observation provides an introduction to the contrasting concepts of Laplacian determinism and chaos. The rest of the unit involves a step-by-step study of a pendulum system that becomes increasingly complex until it is driven into chaotic motion. The time series graphs and phase plots of various configurations of the pendulum are created using a computer data acquisition system with a rotary motion sensor. These experimental results are compared to iterative spreadsheet models developed by students based on the nature of the torques the system experiences. The suitability of the unit for introductory physics students in traditional laboratory settings is discussed.

Topics
Chaotic systems, Data acquisition, Pendulum system, Operator theory, Education
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An excellent introduction to numerical integration can be found in R. Feynman, R. Leighton, and M. Sands, The Feynman Lectures on Physics (Addison–Wesley, Reading, MA, 1963), Vol. 1, Chap. 9, pp. 9-4–9-8.
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© 2004 American Association of Physics Teachers.
2004
American Association of Physics Teachers
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