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arXiv · 1306.4952

Hertz Beyond Belief

Andong He·John S. Wettlaufer
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Abstract

We examine the validity of Hertz's linear elastic theory for central collisions using a viscoelastic model. This model explains why Hertz's theory is accurate in predicting the collision time and maximum contact area even when $40\%$ of the kinetic energy is lost due to viscous dissipation. The main reason is that both the collision time and maximum contact area have a very weak dependence on the impact velocity. Moreover, we show that colliding objects exhibit an apparent size dependent yield strength, which results from larger objects dissipating less energy at a given impact velocity.

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Andong He, John S. Wettlaufer. 2013-06-20. Hertz Beyond Belief. https://arxiv.org/abs/1306.4952

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