Question

27. For a chain nuclear fission of U$^{235}$ the moderation of neutron is a must because very high energy neutron: (1) will collide inelastically with the nucleus and so there is no fission (2) will collide elastically with the nucleus and so there is no fission (3) will be trapped in the nucleus and hence no fission (4) repelled by nucleus

          27. For a chain nuclear fission of U$^{235}$ the moderation of
neutron is a must because very high energy neutron:
(1) will collide inelastically with the nucleus and so there
is no fission
(2) will collide elastically with the nucleus and so there
is no fission
(3) will be trapped in the nucleus and hence no fission
(4) repelled by nucleus

27. For a chain nuclear fission of U^235 the moderation of
neutron is a must because very high energy neutron:
(1) will collide inelastically with the nucleus and so there
is no fission
(2) will collide elastically with the nucleus and so there
is no fission
(3) will be trapped in the nucleus and hence no fission
(4) repelled by nucleus

Added by Francisco Jose G.

University Physics with Modern Physics

Hugh D. Young 14th Edition

Thanks for your feedback!

For a chain nuclear fission of U-235, the moderation of neutrons is a must because very high-energy neutrons will not undergo fission. They will collide elastically with the nucleus, resulting in no fission. If the neutrons are trapped in the nucleus, there will also be no fission. Additionally, if the neutrons are repelled by the nucleus, fission will not occur.