Dual Nature of Radiation and Matter - Result Question 54
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58. The photoelectric work function for a metal surface is $4.125 eV$. The cut off wavelength for this surface is
======= ####58. The photoelectric work function for a metal surface is $4.125 eV$. The cut off wavelength for this surface is
3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/dual-nature-of-radiation-and-matter/dual-nature-of-radiation-and-matter—result-question-54.md (a) $4125 \AA$
(c) $6000 \AA$
(b) $3000 \AA$
(d) $2062.5 \AA$
[1999]
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Answer:
Correct Answer: 58. (b)
Solution:
- (b) Let $\lambda_0$ be cut off wavelength.
Work function $=\frac{h c}{\lambda_0}=4.125 \times 1.6 \times 10^{-19}$
$\lambda_0=\frac{6.626 \times 10^{-34} \times 3 \times 10^{8}}{4.125 \times 1.6 \times 10^{-19}}=3000 \AA$