2017 · Q30
A photon of X-ray has energy of 1 keV, A photon of visible radiation has energy of 3 eV. In this context, which one of the following statements is not correct?
General KnowledgePhysics
- AThe wavelength of X-ray photon is less than the wavelength of visible radiation photon.
- BBoth the photons have different energies.
- CThe speeds of both the photons in vacuum are different.
- DThe frequency of X-ray photon is higher than the frequency of visible radiation photon.
Explanation
In vacuum every photon travels at c regardless of its energy, so the X-ray and visible photons have identical speeds — making statement C the incorrect one. The 1 keV X-ray photon does have a shorter wavelength, higher frequency, and different energy than the 3 eV visible photon. Hence C.