Moderator in nuclear plants is used to
Reduce temperature
Extract heat from nuclear reaction
Control the reaction
Cause collision with the fast moving neutrons to reduce their speed
Correct Answer :
D. Cause collision with the fast moving neutrons to reduce their speed
Related Questions
Reflector in nuclear power plants _________ neutron leakage.
Increases
Decreases
Have no effect on
None of these
Which of the following particles is the lightest?
Nucleus
Electron
Proton
Meson
U233 is produced
As basic raw material
By neutron irradiation of Uz
By neutron irradiation of thorium
Artificially
Boiling water reactor uses the following as moderator, coolant and working fluid
Ordinary fluid
Heavy water
Molten lead
Hydrogen gas
Enriched uranium is required as a fuel in a nuclear reactor, if light water is used as moderator and coolant, because light water has
High neutron absorption cross-section
Low moderating efficiency
High neutron scatter cross-section
Low neutron absorption cross-section
In boiling water reactor, moderator is
Coolant itself
Ferrite rod
Graphite rod
Liquid sodium metal
A fast breeder reactor uses following as fuel
Enriched uranium
Plutonium
Thorium
U₂₃₅
Plutonium (Pu₂₃₉) is produced
Artificially
By fission of Th₂₃₂
When U₂₃₈ is irradiated by neutrons
As basic raw material
Which of the following statement is correct regarding the features of a Breeder reactor?
It produces more fuel than it consumes.
It requires highly enriched fuel.
It requires liquid sodium metal as moderator.
All of the above
Ferrite material is
The most fissionable material
The basic fuel for nuclear paints
Basic raw material for nuclear plants
The material which absorbs neutrons and undergoes spontaneous changes leading to the formation of fissionable material
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
A fission chain reaction in uranium can be developed
By increasing the contents of U₂₃₅
By slowing down fast neutrons so that U₂₃₅ fission continues by slow neutron
Both (A) and (B)
None of these
Reflector in nuclear plants is used to
Return the neutrons back into the core
Shield the radioactivity completely
Check pollution
Conserve energy
U238 will undergo fission by
High energy (fast) neutrons alone
Low energy (slow) neutrons alone
Either fast or slow neutrons
Medium energy neutrons
The breeding gain in case of thermal breeder reactor as compared to fast breeder reactor is
Same
Lower
Higher
Unity
Pick up the wrong statement
In a heterogeneous or solid fuel reactor, the fuel is mixed in a regular pattern within moderator.
Slow or thermal neutrons have energy of the order or 0.025 eV
Fast neutrons have energies above 1000 eV
Fast reactor uses moderator
The predominant isotope of the naturally occuring element is
U₂₃₅
U₂₃₈
Pu₂₃₃
Pu₂₃₉
Hydrogen is preferred as better coolant in comparison to CO₂ because former
Is lighter
Is inert
Has high specific heat
Is a good conductor
The process by which a heavy nucleus is spitted into two light nuclei is known as
Splitting
Fission
Fusion
Disintegration
The primary fuel used in nuclear power plants is
U₂₃₅
U₂₃₈
Pu₂₃₉
Pu₂₃₃
Natural uranium is made up of
99.282% U₂₃₈, 0.712% U₂₃₅, 0.006% U₂₃₄
99.282% U₂₃₅, 0.712% U₂₃₈, 0.06%' U₂₃₄
99.282% U₂₃₄, 0.712% U₂₃₈, 0.006% U₂₃₅
99.282% U₂₃₅, 0.712% U₂₃₄, 0.006% U₂₃₈
Which of the following are ferrite materials?
U₂₃₃ and Pu₂₃₉
U
U₂₃₈ and Pu₂₃₉
U₂₃₈ and Th₂₃₉
Boiling water reactor employs
Boiler
Direct cycle of coolant system
Double circuit system of coolant cycle
Multi passes system
The nuclear radiators produced in a reactor which must be shielded are
Electrons
α, β and γ rays
Neutron and gamma rays
None of these
Each fission of U₂₃₅ produces following number of fast neutrons per fission
1 neutron
3 neutrons
1, 2 neutrons
2 neutrons
A moderator generally used in nuclear power plants is
Graphite
Heavy water
Concrete
Graphite and concrete
Pick up the wrong statement fast breeder reactors
Operate at extremely high power densities.
Are liquid metal cooled
Produce more fuel than they consume
Use water as coolant
Artificial radioactive isotopes find application in
Power generation
Nucleonic devices
Nuclear fission
Medical field
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
The control rods in the control system of nuclear reactors are used to
Absorb excess neutrons
Control fuel consumption
Control temperature
All of these