Derive lorentz transform for energy

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gboff21
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Homework Statement


Derive the relation:
[itex]E' = \gamma (E + \beta p c)[/itex]

Homework Equations


[itex]p' = \gamma p \\<br /> E^{2} = p^{2} c^{2} + M^{2}c^{4}[/itex]

The Attempt at a Solution


start off with stationary frame S [itex]E=mc^{2}[/itex]
then in moving frame S' [itex]E'^{2} = p'^{2} c^{2} + E^{2}[/itex]:
lorent transform momentum:
[itex]E'^{2} = \gamma^{2} m^{2} v^{2}c^{2} + E^{2}[/itex]
and that's as far as I get!
 
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Yes the p is supposed to be unprimed.

I've solved it now. Thanks anyway.
Here it is for anyone who's having the same problem:
You start off (or derive it as I had to, to understand it) with the lorentz transform for velocities in two frames [itex]u = \frac{u'+v}{1+frac{uv}{c^{2}}}[/itex]
Know that [itex]E'=\gamma m_{0}c^{2}[/itex] because in the stationary frame S, only rest mass provides energy.
You expand out gamma with u' given above and recognise that [itex]p'=\gamma p[/itex]
simplify and you get an answer!