A neutron of mass 1.7 × 10-27 kg, travelling at
2.2 km/s, hits a stationary helium nucleus of mass
6.6 x 10-27 kg. After the collision, the velocity
of the helium nucleus is 0.53 km/s at 52° to the
original direction of motion of the neutron.
Determine the final velocity of the neutron
