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JEE Mains · Physics · STD 12 - 11. Dual nature of radiation and matter
When radiation of wavelength \(\lambda\) is used to illuminate a metallic surface, the stopping potential is \(V.\) When the same surface is illuminated with radiation of wavelength \(3 \lambda,\) the stopping potential is \(\frac{ V }{4} .\) If the threshold wavelength for the metallic surface is \(n \lambda\) then value of \(n\) will be......
- A \(9\)
- B \(3\)
- C \(11\)
- D \(16\)
Answer & Solution
Correct Answer
(A) \(9\)
Step-by-step Solution
Detailed explanation
\(\frac{ hc }{\lambda}=\frac{ hc }{\lambda_{0}}+ eV\)\(...(i)\) \(\frac{ hc }{3 \lambda}=\frac{ hc }{\lambda_{0}}+\frac{ e \cdot V }{4}\)\(...(ii)\) (multiply by \(4\)) \(\frac{4 hc }{3 \lambda}=\frac{4 hc }{\lambda_{0}}+ eV\)\(...(iii)\) From \((i)\) \(\&\) \((iii)\)…
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