Nuclear engineering (moderation): In a nuclear reactor, graphite rods serve which primary function in the chain reaction? Focus on the role of graphite in neutron energy control. Choose the correct option.

Difficulty: Easy

React with uranium to release energy
Produce neutrons
Undergo combustion to trigger fission
Convert fast neutrons into thermal neutrons (moderator)

Correct Answer: Convert fast neutrons into thermal neutrons (moderator)

Explanation:

Concept/Approach
Graphite is a moderator. It slows fast neutrons to thermal energies, increasing the probability of fission in certain fuels (e.g., U-235). It neither produces neutrons nor reacts chemically to trigger fission.

Final Answer
Convert fast neutrons into thermal neutrons (moderator)

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