Question

An X-ray machine emits electromagnetic photons carrying a frequency of 7.5x1017hz. What is is the approximate energy carried by each photon?

Answer 1

The energy of a photon

$$E=h\nu$$

$$=6.6\times 10^{-34}\:\rm{J}\cdot\rm{s}\times 7.5\times 10^{17}\:\rm{Hz}$$

$$=5.0\times 10^{-16}\:\rm{J}=3.1\:\rm{keV}$$