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
Correct Answer :
D. Fast reactor uses moderator
Related Questions
When a reactor becomes critical, then the production of neutrons is
Infinite
Zero
Exactly balanced by the loss of neutrons through leakage
Initiated
Breeder reactors employ liquid metal coolant because it
Acts as good moderator
Produces maximum steam
Transfers heat from core at a fast rate
Breeds neutrons
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
Hydrogen is preferred as better coolant in comparison to CO₂ because former
Is lighter
Is inert
Has high specific heat
Is a good conductor
Reactors for propulsion applications are designed for
Any form of uranium
Natural uranium
Enriched uranium
Plutonium
The total energy released in fission of U is
5 MeV
10 MeV
199 MeV
168 MeV
A fast breeder reactor uses
90% U₂₃₅
U₂₃₈
U₂₃₅
Pu₂₃₉
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%
For economical operation of a nuclear plant
Used fuel should be reprocessed
Moderator should be used
Coolant should be employed
Control rods should be used
In triggering fission, the following types of neutrons are desirable
Fast moving
Slow moving
Critical neutrons
Neutrons at rest
The primary fuel used in nuclear power plants is
U₂₃₅
U₂₃₈
Pu₂₃₉
Pu₂₃₃
In order to have constant chain reaction to produce a constant rate of heat output, the value of ratio of the number of neutrons in one generation to the number of neutrons in the immediately preceding generation must be
Greater than 1.0
Less than 1.0
Equal to zero
Equal to 1.0
Electron volt is the unit of
Atomic power
Energy
Voltage
Radio activity
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
Superheated steam is generated in following reactor
Boiling water
Gas cooled
Pressurised water
All of the above
A fast breeder reactor
Uses graphite rods as moderator
Has powerful moderator
Has no moderator
Uses ferrite material as moderator
The presence of reflector in nuclear power plants results in
Increased production of neutrons
Complete absorption of neutrons
Controlled production of neutrons
Decreased leakage of neutrons
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
Plutonium is produced
As basic raw material
By neutron irradiation of Uz
By neutron irradiation of thorium
Artificially
Which of the following is the heaviest?
Neutron
Proton
Atom
Electron
The function of control rods in nuclear plants is to
Control temperature
Control radioactive pollution
Control absorption of neutron
Control fuel consumption
Which is not identical for an atom and an isotope?
Mass number
Atomic number
Chemical properties
Position in periodic table
A reactor capable of converting a ferrite material into fissile isotopes is called
Regenerative reactor
Fast breeder reactor
Breeder reactor
Boiling water reactor
Reactors designed for propulsion applications are designed for
Natural uranium
Enriched uranium
Pure uranium
Any type of uranium
Breeder reactor has a conversion ratio of
Unity
More than unity
Less than unity
Zero
Each fission of U₂₃₅ produces following number of fast neutrons per fission
1 neutron
3 neutrons
1, 2 neutrons
2 neutrons
The material most commonly used for shielding is
Carbon
Lead
Concrete
All of these
In boiling water reactor, moderator is
Coolant itself
Ferrite rod
Graphite rod
Liquid sodium metal
Plutonium (Pu₂₃₉) is produced
Artificially
By fission of Th₂₃₂
When U₂₃₈ is irradiated by neutrons
As basic raw material
U238 will undergo fission by
High energy (fast) neutrons alone
Low energy (slow) neutrons alone
Either fast or slow neutrons
Medium energy neutrons