519. Boiling water reactor uses the following as moderator, coolant and working fluid
A.Ordinary fluid
B.Heavy water
C.Molten lead
D.Hydrogen gas

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520. Ideally the neutron flux in reactor should be
A.Maximum in centre and zero at side
B.Maximum at side and zero in centre
C.Uniform throughout
D.Zero throughout

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521. Enriched uranium may contain fissionable contents of the order of
A.1-99%
B.1-25%
C.1-50%
D.1-75%

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522. U235 will undergo fission by
A.High energy (fast) neutrons alone
B.Low energy (slow) neutrons alone
C.Either fast or slow neutrons
D.Medium energy neutrons

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523. U238 will undergo fission by
A.In a heterogeneous or solid-fuel reactor, the fuel is mixed in a regular pattern within moderator.
B.(a) high energy (fast) neutrons alone
C.(b) low energy (slow) neutrons alone
D.(c) either fast or slow neutrons

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524. A reactor capable of converting a ferrite material into fissile isotopes is called
A.Regenerative reactor
B.Fast breeder reactor
C.Breeder reactor
D.Boiling water reactor

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525. Natural uranium is made up of
A.99.282% U238, 0.712% U235, 0.006% u234
B.99.282% U235, 0.712% U238, 0.06% u234
C.99.282% U234, 0.712% U238, 0.006% U235
D.99.282% U235, 0.712% U234, 0.006% U238

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