In two earlier studies, we demonstrated that due to the enormous accelerations arising during the perpendicular reflection of a photon by a mirror, the photon’s energy distribution behaves as a quadrupole, thereby generating a graviton (or gravitational wavelet) at the same frequency and direction as the reflected photon. The results shown that the energy Eg of a graviton is Eg=χ*ν^3 (where χ* in an universal constant) and not Eg=kν1 as it is hypothesized today in the quantum theories of gravity. For simplicity, in the early studies, only the contribution of the quadrupole component Q_xx at the reflection of a photon by a mirror was previously considered. Here, we extend the analysis to include all quadrupole components associated with perpendicular photon reflection in the case of a resonant cavity. By applying the standard Einstein quadrupole radiation formula, we demonstrate again in a more accurate manner that the energy of the emitted graviton scales as ν^3, revealing a direct coupling between electromagnetism and gravitation. This finding challenges the long-standing but unverified assumption that graviton energy depends linearly on frequency (ν^1). Our results establish that quantum theories of gravity must instead incorporate cubic frequency dependence. The proposed framework provides a new bridge between general relativity and quantum approaches, suggesting that confined electromagnetic radiation can act as a direct source of high-frequency gravitational wavelets.Keywords: gravitation, general relativity, quantum gravity, gravitational wavelets, Nordström—Einstein paradox, quadrupole radiation, graviton generation, resonant cavity.