Question:
In a photoelectric experiment, light of wavelength 800 nm produces photoelectrons with de Broglie wavelength 1 nm, and 400 nm light gives 0.5 nm. Find work function of the metal.
In a photoelectric experiment, light of wavelength 800 nm produces photoelectrons with de Broglie wavelength 1 nm, and 400 nm light gives 0.5 nm. Find work function of the metal.
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Use energy conservation: \( E = \phi + K.E. = hc/\lambda \)
Updated On: May 19, 2025
- 1.03 eV
- 0.53 eV
- 2.03 eV
- 4.03 eV
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The Correct Option is A
Solution and Explanation
From Einstein’s equation:
\[
hc/\lambda = \phi + p^2/2m \Rightarrow \phi = hc/\lambda - p^2/2m
\]
Using both cases and converting units, after simplifying, we find:
\[
\phi \approx 1.03\ \text{eV}
\]
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