# How Sound Waves Travel

Explain that sound is produced by vibrating objects and travels as a longitudinal pressure wave through solids, liquids, and gases; describe reflection of sound (echoes) and absorption; explain why sound cannot travel through a vacuum

Builds on: Wave Properties & Types (hard, https://ai.page/c/wave-properties-and-types/en.md), Sound Travels Through Materials (hard, https://ai.page/c/sound-travels-through-materials/en.md)

Concept id: how-sound-waves-travel. Subject: science. Licence: CC BY-SA 4.0.

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