The main purpose of a moderator in a nuclear reactor is to
A)absorb the neutrons and thereby decrease the reaction rate.
B)absorb the neutrons and thereby increase the reaction rate.
C)slow the neutrons and thereby decrease the reaction rate.
D)slow the neutrons and thereby increase the reaction rate.
E)cool the reactor chamber.

Question

Quizplus · Accepted Answer

The main purpose of a moderator in a nuclear reactor is to slow down the neutrons without absorbing them. This increases the likelihood of these neutrons causing further fission reactions in the fuel, thereby increasing the reaction rate. Fast neutrons are less likely to cause fission in many fuel types, so slowing them down makes the reactor more efficient.

The Main Purpose of a Moderator in a Nuclear Reactor