(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An electron traveling at 0.8c annihilates with a positron that is at rest, producing two photons. One of the produced photons travels in the direction of the electron. Determine the energy of each of the photons.

2. Relevant equations

[tex]p_{photon} = \frac{E}{c}[/tex]

[tex]P_{electron} = \frac{m_e v}{\sqrt{1-v^2/c^2}}[/tex]

3. The attempt at a solution

[tex]p_i = p_f[/tex]

[tex]\frac{m_e v}{\sqrt{1-v^2/c^2}} = 2p_{photon}[/tex]

[tex]E = \frac{m_e 0.9 c^2}{2 \sqrt{1-0.81}} = 8.46 \times 10^{-14} J[/tex]

First of all, I already searched about this frequent topic, but didn't manage to solve the issues. My "issue" is regarding the final momentum. I assume that both photons will have the same momentum, but I don't think that's right.

Thank You ;)

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# Homework Help: Electron and Positron Annihilation

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