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Question
Ultraviolet light is incident on metals P, Q and R, having work functions 8 eV, 2 eV and 4 eV respectively,
- Which metal has lowest threshold frequency for photoelectric effect?
- For which metal is the value of Emax minimum?
(Note: Emax is maximum kinetic energy of the emitted photoelectrons.)
Solution
- The metal (Q) with a work function of 2 eV has the lowest threshold frequency since E0 = hv0.
-
Since, Emax = E - E0, the metal (P) having work function of 8 eV will have minimum Emax.
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