Sound waves

High School

Definition

Longitudinal mechanical waves produced by a vibrating source that travel through a medium as compressions and rarefactions. Their frequency determines pitch and their amplitude determines loudness.

Worked examples

A tuning fork vibrates at \(440\,\)Hz\(\), creating compressions and rarefactions in air that reach your ear as the musical note A.
The vibrating fork pushes and pulls air molecules, sending longitudinal waves through the medium.
Higher frequency (\(880\,\)Hz\(\)) produces a higher pitch; larger amplitude produces louder sound.
Frequency controls what note you hear; amplitude controls how loud it sounds.

Common mistakes

  • Sound waves are transverse waves like lightSound waves are longitudinal mechanical waves Sound travels through compressions and rarefactions parallel to the direction of motion, unlike transverse waves.
  • Sound can travel through a vacuumSound requires a medium (solid, liquid, or gas) to travel Sound is a mechanical wave that needs particles to vibrate and transmit energy.
  • Louder sounds have higher frequencyLouder sounds have greater amplitude, not higher frequency Amplitude determines loudness; frequency determines pitch. They are independent properties.

Where you'll use it next

You'll apply sound waves when studying the Doppler effect, resonance, acoustics, and wave interference in physics, and when exploring how musical instruments and human hearing work.

Found in 1 StudyPug lesson

Unraveling the Science of Sound Waves

Physics 12

Discover the fascinating world of sound waves! From their physical properties to real-world applications, explore how these invisible vibrations shape our auditory experiences and impact various fields of study.

12th Grade12th

See also

Reviewed by Pat Cheng, M.Ed. — StudyPug Curriculum Lead · Last updated June 6, 2026

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