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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 : Number of photons increases with increase in frequency of light. Reason R : Maximum kinetic energy of emitted electrons increases with the frequency of incident radiation. In the light of the above statements, choose the most appropriate answer from the options given below :

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

Correct answer: A is not correct but R is correct.

Solution

The assertion is incorrect because the number of photons is independent of frequency; it depends on the intensity of light. However, the reason is correct as it accurately describes the relationship between frequency and the kinetic energy of emitted electrons, which increases with higher frequency according to the photoelectric effect.

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