The K^0 particle has a mass of 497.7 MeV/c2. It decays into a p- and p+, each having mass 139.6 MeV/c2. Following the decay of a ?0, one of the pions is at rest in the laboratory.
Determine the kinetic energy of the other pion after the decay.
Determine the kinetic energy of the K^0 prior to the decay.