Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason 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
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
- (A)Both and are true but is NOT the correct explanation of
- (B) is false but is true✓ Correct
- (C) is true but is false
- (D)Both and are true and is the correct explanation of
Answer: (B)
Solution
The stopping potential is fixed by , which depends on the frequency of the incident light and not on its intensity, so raising the intensity leaves the stopping potential unchanged and the assertion is false. Increasing the intensity does raise the number of photons arriving each second and hence the rate of photoelectron emission, provided the frequency exceeds the threshold, so the reason is a correct statement. The assertion is false while the reason is true.
JEE Main · 2025 · 04 Apr 2025 · Shift 1 · Single correct option