Sound waves

Science

Definition

Sound waves are longitudinal mechanical waves produced by vibrating objects. They consist of compressions (high-pressure regions) and rarefactions (low-pressure regions) that propagate through a medium. Pitch corresponds to frequency, and loudness corresponds to amplitude.

Examples

  • A tuning fork producing a pure tone at a specific frequency
  • A subwoofer creating low-frequency bass waves you can feel in your chest
  • An ultrasound machine using high-frequency sound waves to image a fetus
Key Fact

Human hearing range: 20 Hz to 20,000 Hz; ultrasound > 20,000 Hz; infrasound < 20 Hz

Related Terms

Sound Wave properties Doppler effect Standing waves

Study This Concept

Practice sound waves with free review games in these units:

Physics Unit 6: Waves and Sound