I have recently bought Einstein's book on the General and Special theory of Relativity and I have finished reading the first half (STR). I understood the ideas and concepts being discussed, as well as the Lorentz transformation, but I have only on question, how did he obtain the relativistic formula for kinetic force ([itex]\frac{mc^2}{\sqrt{1-\frac{v^2}{c^2}}}[/itex]) ?(adsbygoogle = window.adsbygoogle || []).push({});

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# Inquiry about kinetic force in STR

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