Quantum jumps light energy emitted

There was another clue, too. In 1901 the German physicist Max Planck had propounded his quantum theory and shown that atoms emit light in certain discrete quantities, or quanta. An atom could emit one quantum of light, or two, or six, or any other whole number. But it couldn t emit one and a half quanta, or three and a third, or any fractional number. Bohr realized that Planck s result could be explained if the electron in a hydrogen atom could revolve around the nucleus only in certain prescribed orbits with definite energies. It could follow these orbits, but not any in between. An atom emitted light when an electron suddenly made a jump from one orbit to another. 

In 1913, Neils Bohr applied quantum theory to atomic structure, using his analysis of the spectral lines in the light emitted hy hydrogen atoms. Bohr explained the frequencies of these spectral lines hy expressing them in terms of the charge and mass of the electron and Planck s constant He postulated that an atom would not emit radiation while in one of its stable states, hut would do so when it made a transition between states. The frequency of the emitted radiation would be equal to the difference in energy between states divided by Planck s constant An atom could not absorb nor emit radiation continuously but could do so only in finite steps called quantum jumps. 

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