Moderating material used in a thermal-reactor should be a (A) Good absorber of neutrons (B) Solid substance (C) Poor absorber of neutrons (D) None of these

Moderating material used in a thermal-reactor should be a
(A) Good absorber of neutrons
(B) Solid substance
(C) Poor absorber of neutrons
(D) None of these
by

1 Answer

Answer :

(C) Poor absorber of neutrons
by

Related questions

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Description : Which of the following is a moderating material used in nuclear reactor? (A) Graphite (B) Cadmium (C) Zircaloy (an alloy of zirconium and aluminium)

Last Answer : (A) Graphite

An ideal coolant for a nuclear reactor should (A) Be a good absorber of neutrons (B) Be capable of attaining high temperature, only when it is pressurised (C) Have high density, but low heat transfer co-efficient (D) Be free from radiation damage and non-corrosive

Description : An ideal coolant for a nuclear reactor should (A) Be a good absorber of neutrons (B) Be capable of attaining high temperature, only when it is pressurised (C) Have high density, but low heat transfer co-efficient (D) Be free from radiation damage and non-corrosive

Last Answer : (D) Be free from radiation damage and non-corrosive

Molten sodium is used as a coolant in a fast breeder reactor, because of its (A) Excellent moderating properties (B) Neutron breeding capability (C) Faster heat removal capability from the core (D) Capability to increase the reaction rate in the core

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Last Answer : (C) Faster heat removal capability from the core

Thermal shield is used in high powered nuclear reactors to (A) Protect the walls of the reactor from radiation damageB) Absorb the fast neutrons(C) Slow down the secondary neutrons(D) Protect the fuel element from coming in contact with the coolant

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Last Answer : (A) Protect the walls of the reactor from radiation damage

Heat is generated in a nuclear reactor (thermal) by (A) Combustion of a nuclear fuel e.g. uranium (B) Fusion of atoms of uranium (C) Absorption of neutrons in uranium atoms (D) Fission of U-235 by neutrons

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A thermal nuclear reactor compared to a fast breeder reactor (A) Uses slower neutrons for fission (B) Uses faster neutrons for fission (C) Gives higher power density (D) Requires less fuel to run at the same power level

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Which of the following is not a good moderating material? (A) Concrete (B) Boron (C) 18/8 stainless steel (D) All (A), (B) and (C)

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Reactors in commercial nuclear power plants in the U.S. are often referred to as thermal reactors. A thermal reactor uses: w) fissionable plutonium-239 as fuel. x) a relatively low heat output. y) neutrons moderated to relatively low energies. z) liquid sodium as a coolant.

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The main purpose of control rod in a nuclear reactor is to control the (A) Chain reaction and hence the power output by regulating the number of secondary neutrons causing fission (B) Emission of hazardous radiation (C) Conversion of fissile material into fertile material (D) Velocity of the secondary neutrons

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Neutrons are slowed down in a nuclear reactor by – (1) Fissionable Material (2) Moderator (3) Control rods (4) Cooling system

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In a nuclear reactor the material use for absorbing neutrons is – (1) zinc (2) radium (3) lead (4) cadmium

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Which one of the following best defines the word “allotropes”? A Different structural forms of an element B A pair of substances that differ by H+ C Elements that possess properties intermediate between those of metals and nonmetals D Atoms of a given atomic number that have a specific number of neutrons E The different phases (solid, liquid or gas) of a substance

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In a nuclear reactor the moderator is usually made of graphite placed between the fuel rods used to slow down neutrons all of the above none of the above?

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