Himachal Pradesh PSC: Nuclear Reaction and Atomic Energy

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Nuclear Reaction

  • A nuclear reaction is one in which a nucleus bombarded with an elementary particle (like neutron, proton, etc.) or with another nucleus to produce other products in a very short time span.

  • The First nuclear reaction was discovered by Rutherford in 1919, when he bombarded nitrogen with alpha particles.

Nuclear Fission

  • Nuclear fission is the fragmentation of a large nucleus into two smaller nuclei and the liberation large amount of energy.

  • In 1939 the German scientists Otto Hahn and F Steersman observed that when uranium was bombarded with slow neutrons, then two smaller products were obtained with a tremendous amount of heat.

  • The splitting of uranium was called nuclear fission.

Types of Nuclear Fission

  • Controlled nuclear fission Carried out in nuclear reactors in which rate of fission reaction is reduced and energy produced can be used for constructive purposes.

  • Uncontrolled nuclear fission In an atom bomb uncontrolled fission takes place. A very large amount of heat is produced and the process continues until the entire amount of fissionable material is exhausted.

First Atom Bomb

  • On August 6, 1945, an atom bomb was dropped on Hiroshima city in Japan.

  • The second bomb was dropped on Nagasaki, another city of Japan on August 9, 1945. The bomb was made of plutonium - 239.

Nuclear Fusion

  • It is nuclear reaction in which lighter nuclei fuse to form a nucleus of greater mass.

  • In this reaction also an enormous amount of heat is produced.

  • By carrying on nuclear fusion under controlled conditions, the large amount of energy could be made available for useful purpose.

Atomic Energy (Nuclear Energy)

  • Energy produced by nuclear fission or nuclear fusion is called nuclear energy or atomic energy.

  • In nuclear reactions there is loss of mass. This mass is converted into energy. It can be transformed into electrical and mechanical energy which can be used for various peaceful purposes.