Explain the main parts of a nuclear reactor with a neat labelled diagram. Mention its uses.
How to lay out the answer. Follow the frame, then write it in your own words.
1 · Define. A nuclear reactor is a device in which a controlled, self-sustaining fission chain reaction takes place.
2 · Draw the diagram. [Diagram: core with fuel rods, moderator and control rods inside a concrete shield; coolant loop to a heat exchanger; steam to a turbine and generator]
3 · Explain the parts.
Fuel: U-235 or Pu-239; undergoes fission.
Neutron source: beryllium with polonium, radium or plutonium; starts the reaction.
Moderator: graphite or heavy water; slows the neutrons.
Control rods: boron or cadmium; absorb neutrons.
Coolant: water or liquid sodium; removes the heat.
Shielding: thick concrete and lead; stops radiation.
4 · Uses.
Generating electricity.
Producing radioisotopes.
Breeder reactors make Pu-239.
Powering submarines; research.
5 · Real-life link. Kudankulam and Kalpakkam in Tamil Nadu supply electricity to the grid.
6 · Close. Unlike an atom bomb, a reactor keeps the chain reaction under control with its control rods.
Scoring tip: Label at least six parts on the diagram, and give each part's material and job in one line.
