Ahydrogen atom initially in the n 3 level emits a photon and ends up in the ground state. (a) what is the energy of the emitted photon?

The energy levels of the hydrogen atom are given by

where n is the level number.

For n=3 we have

while for n=1 (ground state) we have


The energy of the emitted photon is equal to the energy difference between the two levels in the transition from n=3 to n=1:


In joule, this corresponds to

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