Nuclear and particle physics

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Question 1

a.

Explain the functions of the moderator and the coolant in a nuclear fission reactor.

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b.

Some nuclear fission reactors use uranium-235 as fuel. In the future, there is a possibility of using a deuterium-tritium mixture as fuel in fusion reactors.

Here is some information and data on these fission and fusion reactions:

	Fission reactor	Fusion reactor
Typical reaction	$01n^{1}_{0}\text{n} + {}^{235}_{92}\text{U} \to {}^{141}_{56}\text{Ba} + {}^{92}_{36}\text{Kr} + 3\,^{1}_{0}\text{n}$	$12H+13H→24He+01n^{2}_{1}\text{H} + {}^{3}_{1}\text{H} \to {}^{4}_{2}\text{He} + ^{1}_{0}\text{n}$
Approximate energy produced in each reaction	$MeV180\text{ MeV}$	$MeV17.6\text{ MeV}$
Molar mass of fuel	uranium-235: $mol−10.235\text{ kg mol}^{-1}$	D-T reacting pair: $mol−10.005\text{ kg mol}^{-1}$

Describe the similarities and the differences between fission and fusion reactions.
Explain, with the help of calculations, which fuel produces more energy per kilogram.

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