[amp_mcq option1=”react with U to release energy” option2=”produce neutrons” option3=”undergo combustion which triggers the nuclear fission” option4=”convert fast moving neutrons into thermal neutrons” correct=”option4″]
The correct answer is: D. convert fast moving neutrons into thermal neutrons.
Graphite rods are used in nuclear reactors to slow down fast-moving neutrons. This is important because nuclear fission can only occur when neutrons are moving slowly enough to be captured by the uranium-235 nuclei. The graphite rods do this by scattering the neutrons, which causes them to lose energy.
The other options are incorrect. Option A is incorrect because graphite does not react with uranium. Option B is incorrect because graphite does not produce neutrons. Option C is incorrect because graphite does not undergo combustion.
I hope this helps! Let me know if you have any other questions.