In a nuclear reactor, moderators slow down the neutrons which come out in a fission process. The moderator used have light nuclei. Heavy nuclei will not serve the purpose, because
(a) They will break up
(b) Elastic collision of neutrons with heavy nuclei will not slow them down
(c) The net weight of the reactor would be unbearably high
(d) Substances with heavy nuclei do not occur in liquid or gaseous state at room temperature

1 Views|Posted 8 months ago

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Alok Kumar Singh | Contributor-Level 10

8 months ago

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- (b)

Explanation- the moderator used have light nuclei . because when we use heavy nuclei then there will be collision of proton which does not slow down the process.

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Physics Ncert Solutions Class 12th 2023

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