alleryStart learning →Why can sound not travel across a vacuum?
AThere is no matter there to disturb
BA vacuum is too cold for any sound
CSound is absorbed by empty space
DA vacuum has too high a density
Answer & Solution
Correct answer: A. There is no matter there to disturb
1. Sound is defined as a disturbance of matter passed outward from its source.
2. A disturbance of matter needs matter present to be disturbed.
3. A vacuum contains no matter, so there is nothing to carry the disturbance.
4. Sound therefore requires a medium, which is why space is silent.
_Source: OpenStax Physics (high school, CC BY 4.0), Ch 14 "Sound", section Properties of Sound Waves_
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