Assertion :- Mirage appears in hot summer days.
Reason :- Refractive index of air decreases with height from hot surface

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are False.

Answer

To solve the assertion and reason question regarding mirages, we will follow a step-by-step approach:

### Step 1: Analyze the Assertion
The assertion states: "Mirage appears in hot summer days."
- **Explanation**: A mirage is an optical illusion that occurs when light rays bend due to temperature differences in the air. On hot days, the ground heats the air above it, creating a gradient of temperatures. This phenomenon is commonly observed in deserts or on hot roads, where the illusion of water appears.
- **Conclusion**: The assertion is **correct**.

### Step 2: Analyze the Reason
The reason states: "Refractive index of air decreases with height from hot surface."
- **Explanation**: The refractive index of air is affected by temperature. Hot air is less dense than cold air, meaning that as you go higher (away from the hot surface), the air becomes cooler and denser, leading to an **increase** in the refractive index. Therefore, the statement that the refractive index decreases with height is incorrect.
- **Conclusion**: The reason is **incorrect**.

### Step 3: Determine the Relationship
Now, we need to determine if the reason correctly explains the assertion.
- Since the assertion is true and the reason is false, the reason does not provide a valid explanation for the assertion.

### Final Conclusion
Based on our analysis:
- The assertion is true.
- The reason is false.
- Therefore, the correct answer is that the assertion is true, but the reason is false.

### Answer: C (Assertion is true, Reason is false)

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