JEE Mains · Physics · STD 12 - Dual nature of radiation and matter
- JEE Mains 2025
- Medium
- MCQ
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason \(\mathrm{R}\)
Assertion A: In photoelectric effect, on increasing the intensity of incident light the stopping potential increases.
Reason R : Increase in intensity of light increases the rate of photoelectrons emitted, provided the frequency of incident light is greater than threshold frequency.
In the light of the above statements, choose the correct answer from the options given below
Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(\mathrm{A}\) is false but \(\mathrm{R}\) is true
Step-by-step Solution
Detailed explanation
\(\mathrm{V}_{\mathrm{S}}=\frac{\mathrm{hv}-\phi}{\mathrm{e}}\)
so stopping potential doesn't depend on Intensity
\(\mathrm{I}=\frac{\eta \mathrm{hv}}{\mathrm{~A}}\)
On increasing intensity no. of photons per sec. \(n\) increases so the no. of electrons.
so stopping potential doesn't depend on Intensity
\(\mathrm{I}=\frac{\eta \mathrm{hv}}{\mathrm{~A}}\)
On increasing intensity no. of photons per sec. \(n\) increases so the no. of electrons.
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