The first controlled fission of an atom was carried out in 1938 in which country?

The first controlled fission of an atom was carried out in 1938 in Germany by the physicists Otto Hahn and Fritz Strassmann. This landmark experiment marked the beginning of nuclear fission research and eventually led to the development of nuclear energy and atomic weapons.

Nuclear fission is the process in which the nucleus of a heavy atom, such as uranium-235, splits into two smaller nuclei along with the release of a large amount of energy and additional neutrons. Hahn and Strassmann discovered that when uranium nuclei were bombarded with neutrons, the atom split into lighter elements like barium, proving that the nucleus could be split.

This discovery was explained theoretically by Lise Meitner and Otto Frisch, who described the process and calculated the energy released according to Einstein’s equation, E = mc². The release of energy in nuclear fission comes from the conversion of a small fraction of the nucleus’s mass into energy, which is significantly larger than chemical reactions.

The controlled fission in Germany laid the groundwork for the atomic age. It led to experiments in other countries, including the U.S., for developing nuclear reactors that could generate electricity and nuclear bombs during World War II. Nuclear fission is now harnessed for energy production in nuclear power plants, medical isotopes, and scientific research.

The other options are incorrect:

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  The U.S. and U.K. conducted later fission experiments and developed reactors.

  
  


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  Russia also developed nuclear technology later in the mid-20th century.

  
  

In summary, the first controlled fission of an atom was carried out in 1938 in Germany, a milestone in physics that initiated the exploration of nuclear energy and transformed modern science and technology.