Assertion : Sound waves do not travel through vacuum.
Reason : The speed of sound is too small when compared to speed of light.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion:**
- The assertion states that "Sound waves do not travel through vacuum."
- This is true because sound waves are mechanical waves that require a medium (solid, liquid, or gas) to propagate.

2. **Understanding the Reason:**
- The reason given is that "The speed of sound is too small when compared to the speed of light."
- While it is true that the speed of sound (approximately 330 m/s in air) is much smaller than the speed of light (approximately 3 x 10^8 m/s), this does not explain why sound cannot travel through a vacuum.

3. **Analyzing the Concept of Vacuum:**
- A vacuum is defined as an empty space devoid of any matter.
- Since sound requires a medium (particles) to travel, the absence of any medium in a vacuum means that sound cannot propagate at all.

4. **Conclusion:**
- The assertion is correct: Sound waves do not travel through vacuum.
- The reason provided is incorrect: The inability of sound to travel through vacuum is not due to its speed being small compared to light, but rather due to the absence of a medium in a vacuum.

5. **Final Statement:**
- Therefore, the assertion is true, but the reason is false.

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