Iron emits a K_ X-ray with an energy of 6.4 keV , while calcium emits a K_ X-ray with an energy of 3.69 keV . Determine the time taken by an iron K_ photon and a calcium K_ photon to traverse a distance of 3 km .

Step-by-step solution

Both iron K_ and calcium K_ are X-ray photons, which are electromagnetic waves. All electromagnetic waves travel at the speed of light in vacuum or air, which is c = 3 10^8 m/s , irrespective of their energy or wavelength. The distance to be traversed is d = 3 km = 3 10^3 m . The time taken by both photons is given by t = d c . t = 3 10^3 3 10^8 = 10⁻⁵ s = 10 s . Thus, both photons take 10 s to traverse the distance.