Assertion: Heavy water is a better moderator | vedclass

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(C) moderator is a substance used in a nuclear reactor to slow down fast-moving neutrons to thermal energies through elastic collisions. Heavy water $

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If the Assertion is correct but Reason is incorrect.

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(C) moderator is a substance used in a nuclear reactor to slow down fast-moving neutrons to thermal energies through elastic collisions. Heavy water $(D_2O)$ is an excellent moderator because the mass of the deuterium nucleus is comparable to the mass of a neutron,allowing for efficient energy transfer during collisions. Furthermore,heavy water has a very low neutron absorption cross-section,meaning it does not absorb neutrons significantly. Normal water $(H_2O)$ also acts as a moderator but has a higher probability of absorbing neutrons compared to heavy water. Therefore,the Assertion is correct,but the Reason is incorrect because heavy water absorbs fewer neutrons,not more.

Assertion: Heavy water is a better moderator than normal water.
Reason: Heavy water absorbs neutrons more efficiently than normal water.

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Assertion: Heavy water is a better moderator than normal water.Reason: Heavy water absorbs neutrons more efficiently than normal water.