Franck , James

Franck , James
(1882–1964) German–American physicist
Franck, the son of a banker from Hamburg, was educated at Heidelberg and Berlin where he obtained his doctorate in 1906. After distinguished war service, in which he won two iron crosses, he was appointed to the chair of experimental physics at Göttingen. Although exempt from the 1933 Nazi law that excluded Jews from public office because of his military service, he insisted on publicly resigning. After spending a year in Copenhagen, he emigrated to America in 1935 where he served as professor of physical chemistry at the University of Chicago from 1938 to 1949.
In collaboration with Gustav Hertz he produced experimental evidence of the quantized nature of energy transfer, work that won them the 1925 Nobel Prize for physics. Their experiment, conducted in 1914, consisted of bombarding mercury atoms with electrons. Most of the electrons simply bounced off losing no energy in the process. When the velocity of electrons was increased it was found that on collision with mercury atoms they lost precisely 4.9 electronvolts (eV) of energy. If an electron possessed less energy than 4.9eV it lost none at all on collision; if it had more than 4.9eV it made no difference – only 4.9eV was absorbed by the mercury atoms. Franck and Hertz had thus succeeded in showing that energy can only be absorbed in quite definite and precise amounts. For mercury the minimum amount was 4.9eV. Their results were quickly confirmed and shown to hold for other atoms.
In America Franck worked mainly on the physical chemistry involved in photosynthesis although he is better known as the author of the Franck report published in 1946. This report, actually produced by a number of distinguished scientists of whom Leo Szilard was probably the most important, was sent to the Secretary of State for War in June 1945. It argued that it was not necessary to drop the recently produced atomic bomb on Japan as its explosion on a barren island would be sufficient to force the Japanese into submission.

Scientists. . 2011.

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  • FRANCK, JAMES — (1882–1964), physicist and Nobel prize winner. Franck, who was born in Hamburg, studied chemistry at Heidelberg and Berlin. He then devoted himself mainly to physics. In 1920 he became a professor of experimental physics, directing the second… …   Encyclopedia of Judaism

  • Franck, James — ▪ German physicist born Aug. 26, 1882, Hamburg, Ger. died May 21, 1964, Göttingen, W.Ger.  German born American physicist who shared the Nobel Prize for Physics in 1925 with Gustav Hertz (Hertz, Gustav) for research on the excitation and… …   Universalium

  • Franck, James — (1882 1964)    physicist; his investigations into energy transfer confirmed much of the foundation for modern atomic physics. Born in Hamburg, he studied in Heidelberg (1901 1902) and there formed a lifelong friendship with Max Born.* At Emil… …   Historical dictionary of Weimar Republik

  • Franck, James — (1882–1964)    German physicist and Nobel laureate, 1925. A professor at the University of Gottingen, Franck collaborated with Gustave Hertz in the work on the structure of the atom that was to earn them the 1925 Nobel Prize in Physics.    After… …   Who’s Who in Jewish History after the period of the Old Testament

  • Franck, James — (1882 1964)    German scientist. He was professor at the University of Gottingen. He won the Nobel Prize in 1925. After Hitler s rise to power, he went to the US and taught at Johns Hopkins University and the University of Chicago. During World… …   Dictionary of Jewish Biography

  • Franck, James — ► (1882 1964) Físico alemán. Fue premio Nobel de Física en 1925, junto con G. Hertz, por el establecimiento de las leyes que rigen el choque de un electrón con un átomo …   Enciclopedia Universal

  • Franck — James …   Scientists

  • James Franck — James Franck. James Franck (Hamburgo, Alemania, 26 de agosto de 1882 Gotinga, 21 de mayo de 1964) fue un físico alemán, ganador del Premio Nobel de Física en 1925 …   Wikipedia Español

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