We describe an experiment involving a mass oscillating in a viscous fluid. The mechanical oscillator is tracked using a simple webcam, and an image processing algorithm records the position of the geometrical center as a function of time. Interesting information can be extracted from the displacement-time graphs, in particular, for the underdamped case. For example, we use these oscillations to determine the viscosity of the fluid. Our mean value of for distilled water is in good agreement with the accepted value at . The experiment has been successfully employed in an introductory laboratory setting.
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2010
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