A moderator generally used in nuclear power plants is
Graphite
Heavy water
Concrete
Graphite and concrete
Correct Answer :
D. Graphite and concrete
Related Questions
The efficiency of a nuclear power plant in comparison to conventional and nuclear consideration is
Higher cost of nuclear fuel
High initial cost
High heat rejection in condenser
Lower temperature and pressure conditions
Isotopes of same elements have
Same atomic number and different masses
Same chemical properties but different atomic numbers
Different masses and different atomic numbers
Different chemical properties and same atomic numbers
Hydrogen is preferred as better coolant in comparison to CO₂ because former
Is lighter
Is inert
Has high specific heat
Is a good conductor
Solid fuel for nuclear reactions may be fabricated into various small shapes such as
Plates
Pallets
Pins
Any one of the above
The control rods in the control system of nuclear reactors are used to
Absorb excess neutrons
Control fuel consumption
Control temperature
All of these
Which is not identical for an atom and an isotope?
Mass number
Atomic number
Chemical properties
Position in periodic table
Plutonium is produced
As basic raw material
By neutron irradiation of Uz
By neutron irradiation of thorium
Artificially
A fast breeder reactor uses following as fuel
Enriched uranium
Plutonium
Thorium
U₂₃₅
Each fission of U₂₃₅ produces on the average _________ fast neutrons as a product of reaction.
2.46
24.6
246
2460
Which of the following is more appropriate for a moderator? One which
Does not absorb neutrons
Absorbs neutrons
Accelerates neutrons
Eats up neutrons
The size of the reactor is said to be critical when
Chain reaction can be initiated
It becomes uncontrollable
It explodes
It produces no power
A moderator generally used in nuclear power plants is
Graphite
Heavy water
Concrete
Graphite and concrete
Which of the following particles is the lightest?
Nucleus
Electron
Proton
Meson
A nuclear reactor is said to be critical when the neutron population in the reactor core is
Rapidly increasing leading to the point of explosion
Decreasing from the specified value
Reduced to zero
Constant
The total energy released in fission of U is
5 MeV
10 MeV
199 MeV
168 MeV
Which of the following are ferrite materials?
U₂₃₃ and Pu₂₃₉
U
U₂₃₈ and Pu₂₃₉
U₂₃₈ and Th₂₃₉
The function of control rods in nuclear plants is to
Control temperature
Control radioactive pollution
Control absorption of neutron
Control fuel consumption
Enriched uranium is one in which
Percentage of U₂₃₅ has been artificially increased
Percentage of U has been artificially increased
Percentage of U₂₃₄ has been artificially increased
Extra energy is pumped from outside
In natural uranium, the constituents of three naturally occuring isotopes are
U₂₃₄ = 0.006%, U₂₃₅ = 0.712% and U₂₃₈ = 99.282%
U₂₃₄ = 0.712%, U₂₃₅ = 0.006% and U₂₃₈ = 99.282%
U₂₃₄ = 99.282%, U₂₃₅ = 0.006% and U₂₃₈ = 0.712%
U₂₃₄ = 0.006%, U₂₃₅ = 99.282% and U₂₃₈ = 0.712%
A boiling water reactor uses following as fuel
Enriched uranium
Plutonium
Thorium
U
U233 is produced
As basic raw material
By neutron irradiation of Uz
By neutron irradiation of thorium
Artificially
Fast breeder reactor uses
Boiler
Direct cycle of coolant system
Double circuit system of coolant cycle
Multi passes system
Breeder reactor has a conversion ratio of
Unity
More than unity
Less than unity
Zero
Which of the following nuclear reactor does not need a heat exchanger for generation of steam?
Gas cooled
Liquid metal cooled
Pressurised water
Boiling water
The most practical fuel for a thermonuclear reactor, both from economical and nuclear consideration is
Plutonium
Uranium
Deuterium
Thorium
The predominant isotope of the naturally occuring element is
U₂₃₅
U₂₃₈
Pu₂₃₃
Pu₂₃₉
A moderator, apart from its high neutron slowing power, and low non-productive neutron, should be
Stable under nuclear radiation
Corrosion resistant
Good thermal conductor
All of these
Enriched uranium may contain fissionable contents of the order of
1-99 %
1-25 %
1-50 %
1-75 %
In a fission process, maximum percentage of energy is released as
Kinetic energy of neutrons
Kinetic energy of fission products
Instantaneous release of gamma rays
Gradual radioactive decay of fission products
A moderator, in nuclear power plants, is a medium introduced into the fuel mass in order to
Slow down the speed of fast moving neutrons
Control the reaction
Reduce the temperature
Extracts heat from nuclear reaction