The positive pion decays into a muon and a neutrino. The pion has rest mass [tex] m_\pi [/tex], the muon has [tex] m_\mu [/tex] , while the neutrino has [tex] m_v = 0[/tex]. Assuming the original pion was at rest, use conservation of momentum and energy to show that the speed of the muon is given by:(adsbygoogle = window.adsbygoogle || []).push({});

[tex] \frac{u}{c} = \frac{ (m_\pi/m_\mu)^2 - 1}{ (m_\pi/m_\mu)^2 + 1} [/tex]

I've tried [tex] m_\pi c^2 = \gamma m_\mu c^2 [/tex]. No success with that. I've also tried the relationship [tex] \beta = pmuc/E [/tex]. Still no. I know it SAYS to use conservation of energy and momentum, but I have yet to put together a correct relationship. Any help?

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# Homework Help: Speed of the muon

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