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arXiv · 1710.04481

A study on kinetic friction: the Timoshenko oscillator

Robin Henaff·Gabriel Le Doudic·Bertrand Pilette·Catherine Even·Jean-Marie Fischbach·Frédéric Bouquet·Julien Bobroff·Miguel Monteverde·Claire A. Marrache-Kikuchi
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Abstract

Friction is a complex phenomenon that is of paramount importance in everyday life. We present an easy-to-build and inexpensive experiment illustrating Coulomb's law of kinetic friction. The so-called friction, or Timoshenko, oscillator consists of a plate set into periodic motion through the competition between gravity and friction on its rotating supports. The period of such an oscillator gives a measurement of the coefficient of kinetic friction \mu_k between the plate and the supports. Our prototype is mainly composed of a motor, LEGO blocks, and a low-cost microcontroller, but despite its simplicity the results obtained are in good agreement with values of \mu_k found in the literature.

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Robin Henaff, Gabriel Le Doudic, Bertrand Pilette, Catherine Even, Jean-Marie Fischbach, Frédéric Bouquet, Julien Bobroff, Miguel Monteverde, Claire A. Marrache-Kikuchi. 2017-10-11. A study on kinetic friction: the Timoshenko oscillator. https://doi.org/10.1119/1.5008862

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