Question

Which one of the following is used as a moderator in nuclear reaction?

• A. Uranium
• B. Heavy water
• C. Cadmium
• D. Plutonium

Answer 1

The correct option is B Heavy water

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.

Heavy water can serve as a neutron moderator in a nuclear reactor, which slows down fast particles and encourages the fission reaction

Explanation:

Neutrons in a fission reaction travel either fast or slowly. The fast neutrons tend to be absorbed by certain isotopes of uranium rather than continuing the fission reaction, but the larger deuterium atoms in heavy water help slow down these fast neutrons, ensuring they continue the chain reaction.