[tex]Dane:\\E = 8,28 \ eV\\h = 4,14\cdot10^{-15} \ eV\cdot s\\Szukane:\\f = ?\\\\E = hf \ /:h\\\\f = \frac{E}{h}\\\\f = \frac{8,28 \ eV}{4,14\cdot10^{-15} \ eV\cdot s}\\\\\boxed{f = 2\cdot10^{15} \ Hz = 2 \ PHz}\\\\(1 \ PHz = 10^{15} \ Hz)[/tex]
Odp. Szukana częstotliwość f = 2 PHz.