This definitions covers Key Definitions within Sound Waves for GCSE Physics. Revise Sound Waves in Waves for GCSE Physics with 13 exam-style questions and 15 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 7 of 13 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
📖 Key Definitions
Longitudinal wave: A wave in which particles vibrate parallel to the direction of wave travel, producing compressions and rarefactions.
Compression: A region in a longitudinal wave where particles are pushed together, creating higher pressure.
Rarefaction: A region in a longitudinal wave where particles are spread apart, creating lower pressure.
Ultrasound: Sound waves with a frequency above 20,000 Hz (above the upper limit of human hearing).
Amplitude (sound): The maximum displacement of air molecules from their rest position; greater amplitude = louder sound.
Frequency (sound): The number of compressions passing a point per second; higher frequency = higher pitch.
Practice questions for Sound Waves
What type of wave is sound?
Describe how a sound wave is produced and how energy is transferred by a longitudinal wave.