Assertion (A) : On increasing the internsity of incident radiation, the photoelectrons eject and then KE increases
Reason (R ) : Greater the intensity means greater the energy which in turn means greater the frequency of the radiation.

Options

A. If both (A) and (R ) correct and (R ) is the correct explanation for (A)
B. If both (A) and (R ) correct and (R ) is the correct explanation for (A)
C. If (A) is correct but (R ) is incorrect
D. If both (A) and (R ) are incorrect

Explanation

To solve the question, we need to analyze both the assertion (A) and the reason (R) provided.

### Step 1: Analyze the Assertion (A)
The assertion states: "On increasing the intensity of incident radiation, the photoelectrons eject and then KE increases."

- **Understanding Intensity**: Intensity of radiation is related to the number of photons striking a surface per unit time. Increasing the intensity means more photons are available, which can lead to more photoelectrons being ejected.
- **Kinetic Energy (KE)**: The kinetic energy of the ejected photoelectrons is determined by the energy of the individual photons, which is related to their frequency (E = hf, where h is Planck's constant and f is the frequency).
- **Conclusion**: While increasing intensity increases the number of ejected photoelectrons, it does not increase their kinetic energy. The kinetic energy remains unchanged if the frequency of the incident radiation remains constant.
...