A : Doppler's effect in sound is asymmetric but in light , it is symmetric
R : In Sound , change in frequency depends on the individual velocity of both the source as well as the observer . In light , change in frequency depends on the relative velocity between source and observer .

Answer

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

### Step 1: Understanding the Assertion
The assertion states that "Doppler's effect in sound is asymmetric but in light, it is symmetric."

- **Asymmetric in Sound**: This means that the change in frequency observed depends on whether the source is moving or the observer is moving. The frequencies heard will differ based on the direction and speed of both the source and observer.

- **Symmetric in Light**: This indicates that the change in frequency (or wavelength) observed due to the Doppler effect is the same regardless of whether the source or observer is moving.

**Conclusion**: The assertion is correct.

### Step 2: Understanding the Reason
The reason states that "In Sound, change in frequency depends on the individual velocity of both the source as well as the observer. In light, change in frequency depends on the relative velocity between source and observer."

- **Sound**: The frequency change is influenced by both the speed of the source and the speed of the observer. If either one moves, it affects the frequency differently based on their velocities.

- **Light**: The frequency change is determined solely by the relative velocity between the source and the observer. It does not matter which one is moving; the effect is the same.

**Conclusion**: The reason is also correct.

### Step 3: Analyzing the Relationship Between Assertion and Reason
Both the assertion and the reason are correct, and the reason correctly explains the assertion.

### Final Conclusion
Since both the assertion and reason are correct, and the reason explains the assertion, the answer to the question is:

**Option 1: Both A and R are correct, and R is the correct explanation of A.**

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