What controls a chain reaction?

What controls a chain reaction?

A fission chain reaction takes place when a neutron and a fissile isotope interact with each other. Nuclear power plants use controlled chain reactions. There, the chain reactions are controlled by controlling the rate of nuclear reactions. Controlled chain reactions can easily be converted into uncontrolled form.

Which material is used in controlling chain reaction in a nuclear reactor Mcq?

Chain reaction is controlled either by removing in the fuel rods by or inserting neutron absorbs materials. The material use for control rods must have very high absorption capacity for neutrons. The commonly used materials for control rod are cadmium, hafnium or boron. Thorium.

What device is used to control the chain reaction during fission?

A control rod is a device that is used to absorb neutrons so that the nuclear chain reaction taking place within the reactor core can be slowed down or stopped completely by inserting the rods further, or accelerated by removing them slightly.

How is chain reaction controlled in atomic reactor?

Inside the reactor vessel, the fuel rods are immersed in water which acts as both a coolant and moderator. The moderator helps slow down the neutrons produced by fission to sustain the chain reaction. Control rods can then be inserted into the reactor core to reduce the reaction rate or withdrawn to increase it.

Which one is used as control rod of nuclear reactor?

boron
A rod, plate, or tube containing a material such as hafnium, boron, etc., used to control the power of a nuclear reactor.

How controllable nuclear fission and fusion reactions are?

Fission is used in nuclear power reactors since it can be controlled, while fusion is not utilized to produce power since the reaction is not easily controlled and is expensive to create the needed conditions for a fusion reaction.

Which material is used as control rod in a nuclear reactor?

A rod, plate, or tube containing a material such as hafnium, boron, etc., used to control the power of a nuclear reactor. By absorbing neutrons, a control rod prevents the neutrons from causing further fissions.

Which of the following material can be used as a moderator Mcq?

Explanation: At present the common moderator materials used are graphite, ordinary water and heavy water.

Why are control rods made of cadmium?

Cadmium rod is used as an absorbing material to control the reaction rate of neutrons in a nuclear reactor because Cadmium rod has a high cross-sectional area.

Why is the reactor filled with graphite?

What does graphite do in Advanced Gas-cooled Reactors? The graphite bricks act as a moderator. They reduce the speed of neutrons and allow a nuclear reaction to be sustained.

What is fission chain reaction?

A chain reaction refers to a process in which neutrons released in fission produce an additional fission in at least one further nucleus. This nucleus in turn produces neutrons, and the process repeats. The process may be controlled (nuclear power) or uncontrolled (nuclear weapons).

Why is graphite used in control rods?

Graphite is a moderator. It slows down neutrons so that they can initiate fission when they are absorbed by the nucleus of a U-235 atom.