I'm reading in a book that the recoil kinetic energy of an atom after the emission of a photon is:(adsbygoogle = window.adsbygoogle || []).push({});

Kr = (E1 - E2)^2 / 2Mc^2

Where M is the mass of the atom and E1 is the initial level from where the electron jumped back to E2, producing the photon.

Is this true? where does it come from?

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# Recoil Kinetic Energy

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