Sir James Chadwick CH FRS ( 20 October 1891 - 24 July 1974 ) was an English physicist who was awarded the 1935 Nobel Prize in physics for his discovery of the neutron in 1932 .
Sir James Chadwick CH FRS , ( 20 October 1891 - 24 July 1974 ) was an English physicist and Nobel Prize winner who is best known for discovering the neutron .