Breeder reactor has a conversion ratio of
Unity
More than unity
Less than unity
Zero
Correct Answer :
B. More than unity
Related Questions
A fission chain reaction in uranium can be developed by
Slowing down fast neutrons so that Uz fission continues by slow motion neutrons
Accelerating fast neutrons
Absorbing all neutrons
Using moderator
Reflector in nuclear power plants _________ neutron leakage.
Increases
Decreases
Have no effect on
None of these
The total energy released in fission of U is
5 MeV
10 MeV
199 MeV
168 MeV
Plutonium (Pu₂₃₉) is produced
Artificially
By fission of Th₂₃₂
When U₂₃₈ is irradiated by neutrons
As basic raw material
A moderator generally used in nuclear power plants is
Graphite
Heavy water
Concrete
Graphite and concrete
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
U₂₃₃ is produced
Artificially
As basic raw material
When thorium is irradiated by neutrons
By fission of U₂₃₈
When a reactor becomes critical, then the production of neutrons is
Infinite
Zero
Exactly balanced by the loss of neutrons through leakage
Initiated
Gas cooled reactor uses following materials as moderator, and coolant
Graphite, CO2
Graphite, air
Heavy water, CO2
Lead, H2
Reflector in nuclear plants is used to
Return the neutrons back into the core
Shield the radioactivity completely
Check pollution
Conserve energy
Which of the following particles is the lightest?
Nucleus
Electron
Proton
Meson
A reactor capable of converting a ferrite material into fissile isotopes is called
Regenerative reactor
Fast breeder reactor
Breeder reactor
Boiling water reactor
Plutonium (Pu239) is produced
Artificially
When U238 is irradiated by neutrons
By fission of Th232
As basic raw material
Reactors for propulsion applications are designed for
Any form of uranium
Natural uranium
Enriched uranium
Plutonium
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
Breeder reactor has a conversion ratio of
Unity
More than unity
Less than unity
Zero
Each fission of U₂₃₅ produces on the average _________ fast neutrons as a product of reaction.
2.46
24.6
246
2460
The secondary fuel used in nuclear power plants is
U₂₃₃ and Pu₂₃₉
U₂₃₅ and Th₂₃₂
U₂₃₅ and Pu₂₃₈
U₂₃₃ and Pu₂₃₈
A nuclear fission produces energy of following order in MeV
20
200
2000
20,000
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
The energy produced by a thermal reactor of same size as a breeder reactor is
Almost same
Slightly more
Slightly less
Much less
U233 is produced
As basic raw material
By neutron irradiation of Uz
By neutron irradiation of thorium
Artificially
The primary fuel used in nuclear power plants is
U₂₃₅
U₂₃₈
Pu₂₃₉
Pu₂₃₃
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
The breeding gain in case of thermal breeder reactor as compared to fast breeder reactor is
Same
Lower
Higher
Unity
The coolant used in boiling water reactor is
CO2
Pressurised water
Mixture of water and steam
Liquid metal
A nuclear unit becoming critical means
It is generating power to rated capacity
It is capable of generating much more than rated capacity
There is danger of nuclear spread
Chain reaction that causes automatic splitting of the fuel nuclei has been established
The following present serious difficulty in designing reactor shield
Alpha particles
Beta particles
Thermal neutrons
Fast neutrons and gamma rays
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
Which of the following can be used as a coolant in nuclear plant?
Light or heavy water
Molten lead
Carbon dioxide
Freon