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arXiv · 2101.05632

The falling pencil: a "Divertimento" in four movements

Nicola Cufaro Petroni
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Abstract

The dynamics of a simple pencil with a tip laid on a rough table and set free to fall under the action of gravity is scrutinized as a pedagogic case study. The full inquiry is anticipated by a review of three other simplified movements foreshadowing its main features. A few exact and general results about the sliding angles and the critical static coefficient of friction are established.

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Nicola Cufaro Petroni. 2021-01-05. The falling pencil: a "Divertimento" in four movements. https://arxiv.org/abs/2101.05632

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