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arXiv · 1407.3689

The physics of articulated toys - a jumping and rotating kangaroo

J. Güémez·M. Fiolhais
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Abstract

We describe the physics of an articulated toy with an internal source of energy provided by a spiral spring. The toy is a funny low cost kangaroo which jumps and rotates. The study consists of a mechanical and a thermodynamical analysis which makes use of the Newton and center of mass equations, the rotational equations and the first law of thermodynamics. This amazing toy provides a nice demonstrative example how new physics insights can be brought about when links with thermodynamics are established in the study of mechanical systems.

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J. Güémez, M. Fiolhais. 2014-07-14. The physics of articulated toys - a jumping and rotating kangaroo. https://doi.org/10.1088/0143-0807%2F35%2F4%2F045018

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