Let's say I were to have made a train that travels at $60$ $mph$. Let's also say that I have another train inside of the first train that is also moving at $60$ $mph$ in the same direction. So from an observer standing outside of both trains, the interior train would be moving at $120$ $mph$ whereas the exterior train would be moving at $60$ $mph$. Theoretically, would you be able to have multiple trains moving inside one another eventually reaching the speed of light?
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2No, in STR "$60mph+60mph\neq 120mph$" https://en.wikipedia.org/wiki/Velocity-addition_formula – Umaxo Jul 05 '21 at 05:21
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3Does this answer your question? If I run along the aisle of a bus traveling at (almost) the speed of light, can I travel faster than the speed of light? – Nihar Karve Jul 05 '21 at 05:26
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Yeah, thanks for the link. – Kuplar Jul 05 '21 at 05:29
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2What part of NO, NAY, NEVER are people not getting? Should we all be shouting louder? – m4r35n357 Jul 05 '21 at 08:58
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See this: https://physics.stackexchange.com/questions/597492/nothing-can-exceed-the-speed-of-light-but-what-if-we-accelerate-a-particle-that/597497#597497 – Martin Vesely Jul 07 '21 at 13:00
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The velocity addition you have done pertains primarily to Newtonian mechanics. In special Relativity, we use a different velocity addition formula
$u = \frac{u'+v'}{1+\frac{u' v'}{c^2}}$
Here you can see that if there exists a train travelling at speed of light $0.8c$ and then shoots particle at 0.8c, Galilean velocity addition would give you $1.6c$ whereas the above formula would give you $0.97c$. This condition has arrived because no particle can travel faster than the speed of light. The speed of light being the speed limit is a primary postulate of Special relativity.
joseph h
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