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Question
Radiation from hydrogen discharge tube falls on a cesium plate. Find the maximum possible kinetic energy of the photoelectrons. Work function of cesium is 1.9 eV.
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Solution
Given:
Work function of cesium, Ø = 1.9 eV
Energy of photons coming from the discharge tube, E = 13.6 eV
Let maximum kinetic energy of photoelectrons emitted be K.
From the Einstein's photoelectric equation, we know that the maximum kinetic energy of photoelectrons emitted is given by
K = E − Ø
= 13.6 eV − 1.9 ev
= 11.7 eV
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