COMEDK · Physics · 27. Dual Nature of Matter
Work function of a photosensitive metal is \(3 \mathrm{eV}\). The wavelength of incident radiations which can just eject photoelectrons from the metal is
- A \(600 \mathrm{~nm}\)
- B \(510 \mathrm{~nm}\)
- C \(414 \mathrm{~nm}\)
- D \(378 \mathrm{~nm}\)
Answer & Solution
Correct Answer
(C) \(414 \mathrm{~nm}\)
Step-by-step Solution
Detailed explanation
Given, work function, \(\phi=3 \mathrm{eV}\) The wavelength of incident radiation is given by \(\lambda=\frac{h c}{\phi}=\frac{1242}{\phi}=\frac{1242}{3}=414 \mathrm{~nm}\)
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