Part 1/2 : A neutron in a reactor makes an elastic head- on collision with the nucleus of an atom ini- tially at rest.
Assume: The mass of the atomic nucleus is about 12.4 the mass of the neutron. What fraction of the neutron's kinetic energy is transferred to the atomic nucleus?

Part 2/2 : If the initial kinetic energy of the neutron is 6.97 x 10 ^-13 J, find its final kinetic energy. Answer in units of J.

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