Question

In nuclear reactors, in order to slow
down the fast nuetrons the largest
material should contain​

Answer 1

Explanation:

A moderator is used in nuclear reactors in order to slow down the speed of neutrons.

In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, thereby turning them into thermal neutrons capable of sustaining a nuclear chain reaction involving uranium-235 or a similar fissile nuclide.

Clearly, an obvious way to make a reactor work, and to make use of this characteristic of the 235U(n,f) cross-section, is to slow down the fast, fission neutrons. This can be accomplished, for example, when the neutrons collide with nuclei and scatter in some substance (a moderator).

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