As per Einstein's relation of relativity
[tex]m = \frac{m_0}{\sqrt{1 - \frac{v^2}{c^2}}}[/tex]
here we know that
[tex]m_0 = 207 m_e = 207 \times 9.11 \times 10^{-31} kg[/tex]
[tex]m_0 = 1.88 \times 10^{-28} kg[/tex]
now here we know that
[tex]v = 0.988 c[/tex]
now from above equation mass of the muon is given as
[tex]m = \frac{1.88 \times 10^{-28}}{\sqrt{1 - 0.988^2}}[/tex]
[tex]m = 1.22 \times 10^{-27} kg[/tex]
now for the momentum of muon we can use
[tex]P = mv[/tex]
[tex]P = 1.22 \times 10^{-27} \times 0.988(3 \times 10^8)[/tex]
[tex]P = 3.62 \times 10^{-19} kg m/s[/tex]
so above is the momentum of muon
