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In a nuclear fission reactor, to slow down fast neutrons, we use:

In a nuclear fission reactor, to slow down fast neutrons, we use: Correct Answer Moderator

Concept:

Nuclear reactor:

  • It is a device in which a nuclear reaction is initiated, maintained, and controlled.
  • It works on the principle of controlled chain reaction and provides energy at a constant rate.

Important Points

  • Core-
    • The core of the reactor is the site of nuclear fission.
    • It contains fuel.
  • Reflector-
    • The core is surrounded by a reflector to reduce leakage. 
  • Coolant-
    • Liquid sodium, helium, Liquid oxygen are used as a coolant.
    • The coolant transfers heat produced during fission to a working fluid which in turn may produce steam.
    • The steam drives turbines and generates electricity.
  • Control rods-
    • Cadmium, Boron rods are used as a moderator.
    • They have a high absorption of the capacity of neutrons.
  • Shield-
    • The whole assembly is shielded with heavy steel or concrete to check harmful radiation from coming out.

 

Related Questions

Consider the following statements.
In a nuclear reactor, self-sustained chain reaction is possible because
1. More neutrons are released in each of the fission reactions.
2. The neutrons immediately take park in the fission process.
3. The fast neutrons are slowed down by graphite.
4. Every neutron released in the fission reaction initiates further fission.
Which of these statements are correct?
Consider the following statements: 1. The chain reaction process is used in nuclear bombs to release a vast amount of energy, but in nuclear reactors, there is no chain reaction. 2. In a nuclear reactor, the reaction is controlled, while in nuclear bombs, the reaction is uncontrolled. 3. In a nuclear reactor, all operating reactors are ‘critical’, while there is no question of ‘criticality’ in case of a nuclear bomb. 4. Nuclear reactors do not use moderators, while nuclear bombs use them. Which of the above statements about operational principles of a nuclear reactor and a nuclear bomb is / are correct?
Consider the following statements.
1. The chain reaction process is used in nuclear bombs to release a vast amount of energy, but in nuclear reactors, there is no chain reaction.
2. In a nuclear reactor, the reaction is controlled, while in nuclear bombs, the reaction is uncontrolled.
3. In a nuclear reactor, all operating reactors are 'critical', while there is no question of 'critically' in case of a nuclear bomb.
4. Nuclear reactors do not use moderators, while nuclear bombs use them.
Which of the above statements about operational principles of a nuclear reactor and a nuclear bomb is/are correct?
What does the control rod (cadmium rod) do in a nuclear reactor? A. The fission absorbs excessive heat generated during the reaction and thus prevents excess temperature rise. B. Absorbs extra neutrons to control the chain reaction. C. Reduces the energy of neutrons so that they can be further used for the fission reaction. D. The chain produces the neutrons required for the fission reaction.
In a nuclear reactor, . . . . . . . . is used to control the rate of fission reaction which itself absorbs neutrons without fission.
Which of the following statement/(s) is/are true with regard to "Nuclear Fuel Cycle"? A. It is a series of industrial processes which involve the production of electricity from uranium in nuclear power reactors. B. The nuclear fuel cycles start with the mining of uranium and end with the disposal of nuclear waste. C. To prepare uranium for use in a nuclear reactor, it undergoes the steps of mining, milling, conversion, enrichment, and fuel fabrication. Choose the correct answer from the options given below:
Each fission of U₂₃₅ produces following number of fast neutrons per fission
Each fission of U235 produces following number of fast neutrons per fission
In a nuclear fission reactor, to control the fission rate, we use:
Correct answer for the given blank out of the four alternatives.
The main failings were of conception and a political willingness to settle _________ easy options. _______________ the expansive declarationsof the need "to maintain effective security of all nuclear materials, _______________ includes nuclear materials used in nuclear weapons”, thesummits narrowed their _______________ to civilian holdings __________________ non­nuclear weapon states.
_______________ includes nuclear materials used in nuclear weapons”