00:01
Okay, find the kinetic energies of the two product particles and the following decays.
00:05
So since the masses of a pi plus and a pi minus are the same, so are their energies.
00:15
So using conservation of energy, the energy of the k -on is equal to, since they're equal to times the energy of just, let's just call it the pion.
00:27
So finding the energy of a pion, since we know the energy of the kion is 498 mega electron volts.
00:40
That means the pions have an energy of 249 mega electron volts.
00:48
And the kinetic energy is the energy minus the rest mass energy.
00:56
So we just found e pi.
00:58
The rest mass energy is 140 mega electron volts, and so we get a kinetic energy of 109 mega electron volts.
01:12
So for part b, because of conservation of momentum, the momentum of the neutron is equal to the momentum of the pion, which means by conservation of energy, the energy of the neutron plus the energy of the pi on is equal to the energy of the sigma particle.
01:50
And we know that these two energies are the square root of pnc squared plus m c squared plus the square root of the momentum of the pion and the rest mass energy...