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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

1. Both A and R are true but R is NOT the correct explanation of A
2. A is true but R is false
3. Both A and R are true and R is the correct explanation of A
4. A is false but R is true

Correct answer: A is false but R is true

Solution

The assertion is incorrect because increasing the intensity of light does not affect the stopping potential; it only increases the number of emitted photoelectrons. The reason is correct as it accurately describes that higher intensity leads to more photoelectrons being emitted, assuming the frequency is above the threshold.

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