Neutrons are born out of fission at a high energy and must beslowed down to the low energy region, called the “thermal energyâ€region, to cause another fission. A material called a “moderatorâ€is used to slow the neutrons down, or “moderate†them, by elasticscattering collisions.The average neutron energy coming out offission of thermal neutrons is 1.98 MeV in kinetic energy. What isthe number of collisions required to bring its average kineticenergy to 0.1 eV if it elastically scatters off of the followingmoderators:
a. Hydrogen-1
b. Hydrogen-2
c. Carbon-12
d. Uranium-238
