Mutual Energy of Relative Motions

Wei-Hua Chieng

《Proceedings of the 14th IFToMM World Congress》 14th-3 (2015/10) Pp. 79-82

https://doi.org/10.6567/IFToMM.14TH.WC.OS11.019

並列摘要

A gun with it explosive energy can accelerate the bullet ball, with mass m, from zero velocity to velocity △v. After the gun shoots a ball into the wall, the wall receives an energy of 1/2m(△v)^2 which is converted from the explosive energy to the kinetic energy of the ball and then to heat and/or deformation energy of the wall. When a person carries the same gun on board of a high speed train in the speed V, the observer on the earth will see the kinetic energy change as 1/2m(V+△v)^2 - 1/2 mV^2 = 1/2m(△v)^2 + mV△v when the gun on the train shoots the bullet ball. Where does the extra energy mV△v come from? Is the gun powder explosive energy a frame-of-reference dependent quantity? Does it concern the theory of relativity by Albert Einstein? In this paper, the extra energy mV△v is defined as the mutual energy of the relative motion which is a frame-of-reference dependent energy and may be transferred from one reference frame to the other.

並列關鍵字

Momentum conservation ； Energy Conservation