A photon strikes a hydrogen atom in its ground state to eject the electron with kinetic energy 16.4 eV. If 25% of the photon energy is taken up by the electron, the energy of the incident photon is (24 x X) eV then ‘X’ is:

Explanation

Energy required to just remove the electron =13.6 eV
`:.` Energy required =13.6+16.4=30 eV
If E be the photon energy 25%
E=30 eV, E=120 eV =24x 5 eV.
X=5 Ans.