Assertion Interference shows wave nature of light
Reason Photoelectric effect proves particle nature of light.

Answer

To solve the question regarding the assertion and reason related to the wave and particle nature of light, we can break it down step by step:

### Step 1: Understand the Assertion
The assertion states that "Interference shows the wave nature of light."

**Explanation:**
Interference is a phenomenon that occurs when two or more waves overlap and combine to form a new wave pattern. In the case of light, this can be observed in Young's double-slit experiment, where light passing through two closely spaced slits creates a pattern of bright and dark fringes on a screen. This pattern is characteristic of wave behavior, as it results from constructive and destructive interference of the light waves.

### Step 2: Understand the Reason
The reason states that "Photoelectric effect proves the particle nature of light."

**Explanation:**
The photoelectric effect occurs when light shines on a metal surface and causes the ejection of electrons from that surface. This phenomenon can only be explained if light is considered to consist of particles called photons. The energy of these photons is directly related to the frequency of the light, and this explains why only light above a certain frequency can cause electron ejection, demonstrating the particle nature of light.

### Step 3: Evaluate the Truth of Assertion and Reason
Both the assertion and the reason are true statements:
- The assertion is true because interference patterns are indeed indicative of the wave nature of light.
- The reason is true because the photoelectric effect does demonstrate the particle nature of light.

### Step 4: Determine the Relationship
While both the assertion and reason are true, the reason does not explain the assertion. The wave nature of light shown through interference does not rely on the particle nature of light demonstrated by the photoelectric effect. They are two separate phenomena that illustrate different aspects of light.

### Conclusion
Based on the analysis, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer
Both assertion and reason are correct, but reason is not the correct explanation of assertion.

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