Question: A stationary particle having a rest mass energy of 1400MeV disintegrates into two particles called "pions," a π+ and a π-, that travel in opposite directions, as shown schematically in Fig. Each of the pions has a rest-mass energy of 140MeV.
Fig. - A particle disintegrate into two points
a. Find the kinetic energy, in appropriate units, of each outgoing particle.
b. What is the value of γ ("gamma") for either pion?
c. When the pions are at rest, they have a lifetime of 0.28ns. According to an observer in the laboratory, what is the lifetime of the moving pions (in ns)?