An electron and proton are separated by a large distance. The electron starts approaching the proton with energy 3eV. The proton captures the electrons and forms a hydrogen atom in second excited state. The resulting photon is incident on a photosensitive metal of threshold wavelength 4000A What is the maximum kinetic energy of the emitted photoelectron?
Held on 27 Jul 2021 · Verified 6 Jul 2026.
7.61eV
1.41eV
3.3eV
No photoelectron would be emitted
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