Gravity train of variable mass

Authors

  • Yuji Kajiyama Gifu Shotoku Gakuen University

DOI:

https://doi.org/10.31349/RevMexFisE.21.020213

Keywords:

Gravity train, Gravity tunnel, variable mass system

Abstract

The gravity train is a virtual vehicle that travels in a tunnel across Earth, and its motion due to only gravity is a simple harmonic oscillator. It can run at a constant velocity by appropriately exhausting fuel. In this case, the train obeys the equation of motion for a variable mass system. We discuss the mass and energy reduction of the gravity train during travel and find the optimal conditions for economical travel. This study is suitable for university students in physics classes.

References

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Published

2024-07-01

How to Cite

[1]
Y. Kajiyama, “Gravity train of variable mass”, Rev. Mex. Fis. E, vol. 21, no. 2 Jul-Dec, pp. 020213 1–, Jul. 2024.

Issue

Vol. 21 No. 2 Jul-Dec (2024): Revista Mexicana de Física E

Section

02 Education in Physics

License

Copyright (c) 2024 Yuji Kajiyama

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Authors retain copyright and grant the Revista Mexicana de Física E right of first publication with the work simultaneously licensed under a CC BY-NC-ND 4.0 that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.