In a nuclear reactor, ‘cadmium rods’ are used as which of the following?

Option 3 : Controller

• A nuclear reactor produces and controls the release of energy from splitting the atoms of certain elements. In a nuclear power reactor, the energy released is used as heat to make steam to generate electricity. Hence, controller is the correct answer.

• FUEL: Uranium is the basic fuel. Usually pellets of uranium oxide (UO₂₎ are arranged in tubes to form fuel rods. The rods are arranged into fuel assemblies in the reactor core.
• Moderator: Material in the core which slows down the neutrons released from fission so that they cause more fission. It is usually water, but may be heavy water or graphite.
• Controller: These are made with neutron-absorbing material such as cadmium, hafnium or boron, and are inserted or withdrawn from the core to control the rate of reaction, or to halt it.
• Lubricant: lubricant have shown that it is possible to produce materials capable of lubricating some reactor components. In order to further the development of such lubricants the U.K.A.E.A. and the nuclear manufacturing groups have co-operated in providing lubricant manufacturers.