29. Which of the following can be used as a coolant in nuclear plant
A.Light or heavy water
B.Molten lead
C.Carbon dioxide
D.Freon

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30. Gas cooled reactor uses following materials as moderator, and coolant
A.Graphite, CO2
B.Graphite, air
C.Heavy water, CO2
D.Lead, H2

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31. When a reactor becomes critical, then the production of neutrons is
A.Infinite
B.Zero
C.Exactly balanced by the loss of neutrons through leakage
D.Initiated

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32. The following present serious difficulty in designing reactor shield
A.Alpha particles
B.Beta particles
C.Thermal neutrons
D.Fast neutrons and gamma rays

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33. Which of the following particles is the lightest
A.Nucleus
B.Electron
C.Proton
D.Meson

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34. The size of the reactor is said to be critical when
A.Chain reaction can be initiated
B.It becomes uncontrollable
C.It explodes
D.It produces no power

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35. In the breeder reactors the generation of new fissionable atom is
A.At the lower rate than the consumption
B.At a higher rate than the consumption
C.At an equal rate of the consumption
D.Depends on other considerations

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