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In a nuclear reactor, moderators slow do...

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.

Text Solution

Verified by Experts

In elastic collision, the velocities are exchanged. Heavy nuclei will not serve the purpose as elastic collisions of neutrons with heavy nuclei will not slow them down. The correct option is (b).
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