alleryStart learning →A vibrating guitar string makes a sound. What does it do to the surrounding air?
AIt removes all air from around it
BIt compresses and expands the air
CIt heats the air until it glows
DIt charges the air electrically
Answer & Solution
Correct answer: B. It compresses and expands the air
1. A vibrating string oscillates back and forth about its rest position.
2. Part of its energy goes into compressing and expanding the surrounding air.
3. That creates regions of slightly higher and slightly lower pressure.
4. The higher pressure regions are compressions and the lower ones are rarefactions.
_Source: OpenStax Physics (high school, CC BY 4.0), Ch 14 "Sound", section Properties of Sound Waves_
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