An electron and proton are separated by a large distance. The electron starts approaching the proton with energy \(3 eV\…

An electron and proton are separated by a large distance. The electron starts approaching the proton with energy \(3 eV\). The proton captures the electron and forms a hydrogen atom in second excited state. The resulting photon is incident on a photosensitive metal of threshold wavelength 4000 \(\overset{^\circ }{A}\). What is the maximum kinetic energy of the emitted photoelectron?

[JEE Main 2021, 27 Jul (Shift 2)]