The mechanical energy change of a system in an inertial frame of reference equals work done by the total nonconservative force in the same frame. This relation is covariant under the Galilean transformations from inertial frame S to S′, where S′ moves with constant velocity relative to S. In the presence of nonconservative forces, such as normal and tension forces, the mechanical energy of a system can be conserved in S and not be conserved in S′. In this paper we find useful relations between the mechanical energy changes in two inertial frames of reference.

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See [supplementary material] available under the “References” tab at TPT Online, http://dx.doi.org/10.1119/1.4961180 .

Supplementary Material

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