I was trying to get to the equation E=mc^2, but I can't seem to.(adsbygoogle = window.adsbygoogle || []).push({});

I started with the example of a moving observer with a stationary observer with a beam of light.. (you know, c^2*t^2 = c^2*t'^2+t^2*v^2) and isolated v^2:

v^2 = c^2(t^2-t'^2)/t^2 = c^2(1-(t'/t)^2)

Then took the formula for kinetic energy: E(k) = mv^2/2 and replaced v^2:

E(k) = m*c^2*(1-(t'/t)^2)/2

Now.. I got the right equation except that for it to be correct (1-(t'/t)^2)/2 = 1 so 1-(t'/t)^2 = 2, (t'/t)^2 = -1, t'/t = sqr(-1)

...I think it's pretty obivous I made a mistake somewhere... but where?

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# Where is my error?

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