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:

  1. (b) Let $\lambda_0$ be cut off wavelength.

Work function $=\frac{h c}{\lambda_0}=4.125 \times 1.6 \times 10^{-19}$

$\lambda_0=\frac{6.626 \times 10^{-34} \times 3 \times 10^{8}}{4.125 \times 1.6 \times 10^{-19}}=3000 \AA$