what happens when an electron releases energy

 when an electron releases energy ,it return to its ground state, the energy releases is proportional to the difference between the energy levels. , this is stated in bohr 2^nd atomic postulate,

The electrons present in an atom can move from a lower energy level (E_lower) to a level of higher energy (E_higher) by absorbing the appropriate energy. Similarly, an electron can jump from a higher energy level (E_higher) to a lower energy level (E_lower) by losing the appropriate energy.
The energy absorbed or lost is equal to the difference between the energies of the two energy levels, i.e.,
ΔE= E_higher - E_lower

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