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

[tex] p+^{7}Li \rightarrow ^{4}He +^{4}He[/tex]

Mass of 7Li = 6533.8 MeV/c^2

Calculate the kinetic energy of each helium nucleus if the incident proton has nearly zero kinetic energy. Answer: 8.68MeV

2. Relevant equations

[tex] E_{total}=\frac{mc^{2}}{\sqrt{1-(\frac{v}{c})^2}}[/tex]

3. The attempt at a solution

I tried to apply conservation of momentum here:

[tex]E_{iproton}=mc^{2}=938.27MeV[/tex]

[tex]E_{iLi} = 6533.8MeV[/tex]

By conservation, these quantities should be conserved, so I add them which gives me the wrong answer. I'm definitely missing some crucial concept here. If anyone could help me figure this out I would appreciate it greatly.

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# Homework Help: P+7Li->4He+4He energy of He nuclei

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