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
Correct Answer :
D. Decreased leakage of neutrons
Related Questions
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
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
Gas cooled reactor uses following materials as moderator, and coolant
Graphite, CO2
Graphite, air
Heavy water, CO2
Lead, H2
The energy released during the fission of one atom of Uranium 235 in million electron volts is about
100
200
300
400
The fuel needed, with reflector in nuclear power plant, in order to generate sufficient neutrons to sustain a chain reaction, would be
More
Less
Same
Zero
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
In nuclear fission
The original elements change into completely different elements
The electrons of the element change
The molecules rearrange themselves to form other molecules
None 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 nuclear energy is measured as
MeV
Curie
Farads
MW
A nuclear fission is initiated when the critical energy as compared to neutron binding energy of the atoms is
Same
More
Less
There is no such criterion
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
A fast breeder reactor
Uses graphite rods as moderator
Has powerful moderator
Has no moderator
Uses ferrite material as moderator
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
Reactors for propulsion applications use
Natural uranium
Molten lead
Any form of uranium
Thorium
A fast breeder reactor uses following as fuel
Enriched uranium
Plutonium
Thorium
U₂₃₅
Reactors designed for propulsion applications are designed for
Natural uranium
Enriched uranium
Pure uranium
Any type of uranium
In boiling water reactor, moderator is
Coolant itself
Ferrite rod
Graphite rod
Liquid sodium metal
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
A pressurised water reactor employs pressurises for the following application
To maintain constant pressure in primary circuit under varying load
To Supply high pressure steam
To increase pressure of water in primary circuit
To provide sub cooled water at high pressure
Effective moderators are those materials which contain
Light weight atoms
Heavy weight atoms
Critical atoms
Zero weight atoms
The material most commonly used for shielding is
Carbon
Lead
Concrete
All of these
The primary fuel used in nuclear power plants is
U₂₃₅
U₂₃₈
Pu₂₃₉
Pu₂₃₃
Plutonium (Pu239) is produced
Artificially
When U238 is irradiated by neutrons
By fission of Th232
As basic raw material
Fast breeder reactor uses
Boiler
Direct cycle of coolant system
Double circuit system of coolant cycle
Multi passes system
The commonly used material for shielding is
Lead or concrete
Lead and tin
Graphite or cadmium
Thick galvanised sheets
U₂₃₃ is produced
Artificially
As basic raw material
When thorium is irradiated by neutrons
By fission of U₂₃₈
Nuclear reactors are used
To produce heat for thermoelectric power
To produce fissionable material
To propel ships, submarines, aircrafts
All of these
Which of the following is more appropriate for a moderator? One which
Does not absorb neutrons
Absorbs neutrons
Accelerates neutrons
Eats up neutrons
The most practical fuel for a thermonuclear reactor, both from economical and nuclear consideration is
Plutonium
Uranium
Deuterium
Thorium
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