Description : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The neutrons from the source are of high speed and en
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The ... water B. Graphite C. Beryllium D. Sodium
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission. The ... mass number only D. be all the above three
Last Answer : Moderator is a material which is used to slow down the neutrons produced during nuclear fission ... . absorbs thermal energy. Produced in the reactors
Description : A moderator is used in nuclear reactor in order to ? A. Accelerate the neutrons B. Slow down the speed of the neutrons (Answer) C. Increase the number of elections D. Decrease the number of electrons E. None of these
Last Answer : B. Slow down the speed of the neutrons (Answer)
Description : 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?
Last Answer : Feel Free to Answer
Description : Neutrons are slowed down in a nuclear reactor by – (1) Fissionable Material (2) Moderator (3) Control rods (4) Cooling system
Last Answer : (2) Moderator Explanation: In thermal nuclear reactors, the coolant acts as a moderator that must slow down the neutrons before they can be efficiently absorbed by the fuel. It allows neutrons to slow down to energies where they can easily cause a nucleus to fission.
Description : Neutrons are slowed down in a nuclear reactor by (1) Fissionable material (2) Moderator (3) Control rods (4) Cooling system
Last Answer : Moderator
Description : The number of neutrons accompanying the formationof 54Xe 139 and 38Sr 94 from the absorption of a slow neutron by 92U235 , followed by nuclear fission is (A) 1 (B) 2 (C) 3 (D) 4
Last Answer : (C) 3
Description : The part of the nuclear reactor that controls the speed of neutrons released during nuclear fission is
Last Answer : moderator.
Description : Heavy water used in the nuclear reactors to slow down the speed of neutrons is (A) Highly purified water (B) A compound of oxygen and deuterium (C) Water having dissolved salts of heavy metals (D) None of these
Last Answer : (B) A compound of oxygen and deuterium
Description : 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) ... radiation (C) Conversion of fissile material into fertile material (D) Velocity of the secondary neutrons
Last Answer : (A) Chain reaction and hence the power output by regulating the number of secondary neutrons causing fission
Description : Thermal shield is used in high powered nuclear reactors to (A) Protect the walls of the reactor from radiation damage B) Absorb the fast neutrons (C) Slow down the secondary neutrons (D) Protect the fuel element from coming in contact with the coolant
Last Answer : (A) Protect the walls of the reactor from radiation damage
Description : Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission? (1) Boron (2) Heavy water (3) Uranium (4) Plutonium
Last Answer : (1) Boron Explanation: Boron shielding is used as a control for nuclear reactors, taking advantage of its high cross-section for neutron capture. Elemental boron is rare and ... aluminium. Crystalline boron is chemicallyinert and resistant to attack by boiling hydrofluoric or hydrochloric acid.
Description : wo elements which are used to absorb neutrons to control the chain reaction during nuclear fission are - (1) Boron and Cadmium (2) Boron and Plutonium (3) Cadmium and Uranium (4) Uranium and Boron
Last Answer : (1) Boron and Cadmium Explanation: Since the continued chain reaction of a nuclear fission reactor depends upon at least one neutron from each fission being absorbed by another fissionable nucleus, the ... and then the control rods are slowly lifted until a chain reaction can just be sustained.
Description : The two elements which are used to absorb the neutrons in nuclear fission during chain reaction
Last Answer : Boran and Cadmium
Description : Which of the following can be used to absorb neutrons to control the chain reaction during nuclear fission ? (1) Boron (2) Heavy water (3) Uranium (4) Plutonium
Last Answer : Boron
Description : Two elements which are used to absorb neutrons to control the chain reaction during nuclear fission are (1) Boron and Cadmium (2) Boron and Plutonium (3) Cadmium and Uranium (4) Uranium and Boron
Last Answer : Boron and Cadmium
Description : The function of moderators in nuclear reactor is to (A) Slow down the secondary neutrons (B) Absorb the secondary neutrons (C) Control the chain reaction (D) None of these
Last Answer : (A) Slow down the secondary neutrons
Description : In the nuclear reactors, moderators are used to : (1) Accelerate neutrons (2) Absorb the neutrons (3) Slow down the neutrons (4) Generate neutrons
Last Answer : Slow down the neutrons
Description : 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
Last Answer : (D) Fission of U-235 by neutrons
Description : An element having large number of __________ is most easily subjected to nuclear fission. (A) Protons (B) Electrons (C) Neutrons (D) Nucleons
Last Answer : (D) Nucleons
Description : 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
Last Answer : (A) Uses slower neutrons for fission
Description : Which of the following accounts for the maximum energy release in the nuclear fission process? (A) Kinetic energy of fission products (B) Radioactive decay of fission products (C) Instantaneous release of γ-rays (D) Kinetic energy of neutrons
Last Answer : (A) Kinetic energy of fission products
Description : Most of the new atoms formed when atoms in a nuclear reactor capture neutrons without fissioning are: w) fission products x) activation products y) actinides z) lead isotopes
Last Answer : ANSWER: Y -- ACTINIDES
Description : Of the following, which non-fissioning element is used in the cooling water of nuclear power plants to help control the rate of the fission reaction by absorbing neutrons: w) zirconium x) boron y) krypton z) cesium
Last Answer : ANSWER: X -- BORON
Description : Which of the following terms refers to a material which slows neutrons? w) retarder x) moderator y) buffer z) bottleneck
Last Answer : ANSWER: X -- MODERATOR
Description : A moderator __________ the neutrons. (A) Slows down (B) Absorbs (C) Accelerates (D) Reflects
Last Answer : (A) Slows down
Description : In the fission of U235, what is the average number of neutrons produced in the fission reaction? w) 1.5 x) 2.5 y) 3.5 z) 4.5
Last Answer : ANSWER: X -- 2.5
Description : Fast breeder reactors do not (A) Use Th-232 as fissile fuel (B) Convert fertile material to fissile material (C) Use fast neutrons for fission (D) Use molten sodium as coolant
Last Answer : (A) Use Th-232 as fissile fuel
Description : A fast breeder reactor (A) Utilises fast neutrons for causing fission (B) Converts fertile material (e.g., U-238) into fissile material (Pu-239) (C) Normally employs molten sodium as coolant (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : 1. Alpha-keratin is a protein present in which thing? 2. Where was the first session of the Constituent Assembly held? 3. Which of the following is used as a moderator in nuclear reactor? 4. ... place is the same as which place? 20. What was the script used in the earliest Tamil inscriptions?
Last Answer : Answer : 1. Wool 2. New Delhi 3. Graphite 4. Mars 5. Afghanistan 6. Bangladesh 7. 9 players each 8. Thyroid gland 9. Jupiter 10. Grama 11. Jawaharlal Nehru 12. Plutonium 13. After the drought ... Philosophy 16. A House for Mr. Biswas 17. Gambusia 18. Right to freedom 19. Celestial pole 20. Brahmi
Description : The velocity of thermal (slow) neutrons triggering nuclear fissionreaction (having energy equal to 0.025 eV) is about __________ metres/second. (A) 1100 (B) 2200 (C) 3300 (D) 4400
Last Answer : (B) 2200
Description : A homogeneous reactor is the one, in which the (A) Fissile atoms are evenly distributed throughout the mass of nuclear reactor (B) Same substance (e.g. heavy water) is used as moderator & coolant (C) The fuel and the moderator is mixed to form a homogeneous material (D) All (A), (B) and (C)
Last Answer : (C) The fuel and the moderator is mixed to form a homogeneous material
Description : The most commonly used moderator material in nuclear plant is (1) Carbon (2) Water (3) Co2 (4) Liquid metal
Last Answer : Liquid metal
Description : Ordinary water is not used as a moderator because, it (A) Has a low absorption cross-section (B) Has a low scattering cross-section (C) Absorbs neutrons (D) Does not absorb neutrons
Last Answer : (C) Absorbs neutrons
Description : Energy produced in the nuclear fission is of the order of __________ MeV. (A) 20 (B) 200 (C) 1000 (D) 2000
Last Answer : (B) 200
Description : The sum of masses of two nuclei produced in nuclear fission compared to the mass of original nucleus is (A) Less (B) More (C) Same (D) Much more
Last Answer : (A) Less
Description : Artificially produced radioactive isotopes are used for (A) Power generation (B) Treatment of certain diseases (C) Initiating nuclear fission and fusion (D) All (A), (B) and (C)
Last Answer : (B) Treatment of certain diseases
Description : Plutonium Plutonium is used as _____. A. Fuel for Nuclear Fission B. Fuel for Nuclear Fusion C. Source of Chemical Energy D. Source of Light Energy
Last Answer : ANSWER: A
Description : Plutonium is used as _____. A. Fuel for Nuclear Fission B. Fuel for Nuclear Fusion C. Source of Chemical Energy D. Source of Light Energy
Description : The source of the sun's energy is the process of – (1) Photoelectric emission (2) Nuclear fission (3) Nuclear fusion (4) Thermionic emission
Last Answer : (3) Nuclear fusion Explanation: The Sun formed about 4.6 billion years ago from the gravitational collapse of a region within a large molecular cloud. Most of the matter gathered in the center, ... thermonuclear fusion in its core. It is thought that almost all other stars form by this process.
Description : The source of the Sun's energy is the process of – (1) Photoelectric emission (2) Nuclear fission (3) Nuclear fusion (4) Thermionic emission
Last Answer : (3) Nuclear fusion Explanation: Nuclear fusion is a nuclear reaction in which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. During this process, matter ... fusing nuclei is converted to energy which is released. Fusion is the process that powers active stars.
Description : Pick out the wrong statement. (A) Geothermal energy is a non-conventional source of energy (B) Mass is converted into energy in both nuclear fission & fusion reaction (C) Inhalation of mercury vapour is not harmful for human beings (D) Inhalation of arsenic causes cancer
Last Answer : (C) Inhalation of mercury vapour is not harmful for human beings
Description : The source of the Sun’s energy is the process of (1) Photoelectric emission (2) Nuclear fission (3) Nuclear fusion (4) Thermionic emission
Last Answer : Nuclear fusion
Description : A fertile material is the one, which can be (A) Converted into fissile material on absorption of neutron (B) Fissioned by slow (thermal) neutrons (C) Fissioned by fast neutrons
Last Answer : (A) Converted into fissile material on absorption of neutron
Description : In a nuclear power reactor, fission produces heat which is used to produce electricity. A reactor producing more fissionable material than it consumes is known as what kind of reactor?
Last Answer : ANSWER: BREEDER REACTOR
Description : Who have the highest energy gamma rays or neutrons produced from nuclear reactor?
Last Answer : Not sure
Description : Which of the listed precautions should be observed before spraying liquid solvent on the insulation of an electric motor? A. Slow the motor down to low speed. B. Disconnect the motor from the power source. C. Secure all ventilation in the area. D. Preheat the insulation to assist in cleaning.
Last Answer : Answer: B
Description : Thermal neutrons which are used to cause the fission of U-235 haveenergy __________ eV. (A) < 0.025 (B) > 1 (C) 1-25 (D) > 200
Last Answer : (A) < 0.025