Frank – Hertz Experiment

Abstract

Frank-Hertz experiment was performed by James Frank and Hertz in 1914. James Frank and Gustau Hertz published the results of an experiment which provided strong evidence that Bohr’s model of atoms with quantized energy levels was correct. When they were performing this experiment they weren’t try to test Bohr’s model; infact, they weren’t even aware of Bohr’s theory ! as Frank admitted Later

“It might interest you to know that when we made the experiment that we did not know Bohr’s theory. We had neither read nor heard about it. But we made that experiment (and got the result that confirmed Bohr’s theory) because we hoped that if we was found out where the border line between elastic and inelastic impact lies.....only one line might appear. But we did not know whether that would be so, and we did not know whether at all an emission of an atom is of such a type that one line alone can be emitted and all the energy can be used for that purpose. The experiment gave it to us, and we were surprised about it. But we were not surprised after we read Bohr’s paper later, after our publication.”