part 1 of 2
A neutron in a reactor makes an elastic
head-on collision with the nucleus of an atom
initially at rest.
Assume: The mass of the atomic nucleus is
about 11.1 the mass of the neutron.
What fraction of the neutron's kinetic en-
ergy is transferred to the atomic nucleus?

part 2 of 2
In the initial kinetic energy of the neutron
is 1.77 x 10^-13 J. find its final kinetic energy.
Answer in units of J.