Return the neutrons back into the core
Shield the radioactivity completely
Check pollution
Conserve energy
Mass number
Atomic number
Chemical properties
Position in periodic table
Protons in the nucleus
Electrons in the nucleus
Neutrons in the nucleus
Electrons in the atom
Atomic power
Energy
Voltage
Radio activity
Alpha particles
Beta particles
Thermal neutrons
Fast neutrons and gamma rays
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
1 MeV
2.4 MeV
4.3 MeV
7.8 MeV
At the lower rate than the consumption
At a higher rate than the consumption
At an equal rate of the consumption
Depends on other considerations
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
Boiler
Direct cycle of coolant system
Double circuit system of coolant cycle
Multi passes system
Neutron
Proton
Atom
Electron
U₂₃₃ and Pu₂₃₉
U
U₂₃₈ and Pu₂₃₉
U₂₃₈ and Th₂₃₉
Any form of uranium
Natural uranium
Enriched uranium
Plutonium
Plates
Pallets
Pins
Any one of the above
As basic raw material
By neutron irradiation of Uz
By neutron irradiation of thorium
Artificially
U₂₃₃ and Pu₂₂₉
U₂₃₁ and Pu₂₃₃
U₂₃₅ and Pu₂₃₅
U₂₃₈ and Pu₂₃₉
Increases
Decreases
Have no effect on
None of these
Same
Lower
Higher
Unity
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
Heavy water
Concrete and bricks
Graphite and concrete
Graphite
Increased production of neutrons
Complete absorption of neutrons
Controlled production of neutrons
Decreased leakage of neutrons
Same
More
Less
There is no such criterion
Lead or concrete
Lead and tin
Graphite or cadmium
Thick galvanised sheets
High energy (fast) neutrons alone
Low energy (slow) neutrons alone
Either fast or slow neutrons
Medium energy neutrons
Heavy water
Graphite
Carbon dioxide
No moderator is needed
2.46
24.6
246
2460
Artificially
By fission of Th₂₃₂
When U₂₃₈ is irradiated by neutrons
As basic raw material
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
90% U₂₃₅
U₂₃₈
U₂₃₅
Pu₂₃₉
Boiling water
Gas cooled
Pressurised water
All of the above