Sound can travel in vacuum.

Answer

**Step-by-Step Solution:**

1. **Understanding the Statement**: The statement we need to evaluate is "Sound can travel in a vacuum."

2. **Defining Sound**: Sound is a type of energy that travels in the form of waves. Specifically, it travels as longitudinal waves, which means that the particles of the medium vibrate back and forth in the same direction as the wave travels.

3. **Requirement of a Medium**: For sound to travel, it needs a medium (like air, water, or solids) because sound waves are created by the vibration of particles in that medium. When one particle vibrates, it causes adjacent particles to vibrate, allowing the sound to propagate.

4. **Characteristics of a Vacuum**: A vacuum is defined as a space that is completely empty of matter. This means there are no particles present to vibrate and carry the sound waves.

5. **Conclusion**: Since sound requires a medium to travel and a vacuum has no particles or medium, sound cannot travel in a vacuum. Therefore, the statement "Sound can travel in a vacuum" is **false**.

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