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Question: Answered & Verified by Expert
The surface of the metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68 eV, the work function of the metal is
PhysicsDual Nature of MatterJEE Main
Options:
  • A 1.51 eV
     
  • B 1.42 eV
     
  • C 3.0 eV
     
  • D 1.68 eV
     
Solution:
1732 Upvotes Verified Answer
The correct answer is: 1.42 eV
 
As we know

ϕ0=hcλ-Ek (Einstein's equation)

=    ϕ0=1240 eV nm400 nm-1.68 eV

=   3.1-1.68=1.42 eV

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