Impact-induced acceleration by obstacles

Abstract

We explore a surprising phenomenon in which an obstruction accelerates, rather than decelerates, a moving flexible object. It has been claimed that the right kind of discrete chain falling onto a table falls \emph{faster} than a free-falling body. We confirm and quantify this effect, reveal its complicated dependence on angle of incidence, and identify multiple operative mechanisms. Prior theories for direct impact onto flat surfaces, which involve a single constitutive parameter, match our data well if we account for a characteristic delay length that must impinge before the onset of excess acceleration. Our measurements provide a robust determination of this parameter. This supports the possibility of modeling such discrete structures as continuous bodies with a complicated constitutive law of impact that includes angle of incidence as an input.

arXiv commentsmall changes and corrections, added references

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Cited by in corpus (3)

• Understanding how a falling ball chain can be speeded up by impact onto a surface
• Understanding and enhancing the impact-induced tension of a falling chain
• A simple dynamical model of a freely-falling train of rigid segments