Abstract The symmetry of Lagrangians of a holonomic variable mass system is studied. Firstly, the differential equations of motion of the system are established. Secondly, the definition and the criterion of the symmetry of the system are presented. Thirdly, the conditions under which there exists a conserved quantity deduced by the symmetry are obtained. The form of the conserved quantity is the same as that of the constant mass Lagrange system. Finally, an example is shown to illustrate the application of the result.
Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 10932002 and 10972031) and the Beijing Municipal Key Disciplines Fund for General Mechanics and Foundation of Mechanics.
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