A photon of energy E travelling in the +ve x direction collides elastically with an electron of mass m, moving in the opposite direction. After the collision the photon travels back along the -ve x direction with the same energy E.(adsbygoogle = window.adsbygoogle || []).push({});

Use the conservation of energy and momentum to demonstrate that the initial and final momenta of the electron are equal and opposite and of magnitude E/c.

This question is worth 10 marks and im kinda lost on what to do soany help at all would be greatly appreciated.

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# Homework Help: Relativity Question

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