Study of Sound
Sound waves have properties like frequency, wavelength, and speed, and understanding these helps explain acoustics and sound behaviour.
Core concept
Sound waves are longitudinal waves, meaning particles vibrate parallel to the direction the wave travels, causing compressions and rarefactions.
How it works
The speed of sound varies in different media, travelling fastest in solids, slower in liquids, and slowest in gases like air.
Why it matters
The audible range for humans is typically 20 Hz to 20,000 Hz, with sounds below or above this range called infrasound or ultrasound.
Key detail
Ultrasound, sound above human hearing range, has practical applications in medical imaging, cleaning, and industrial testing.
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• Sound: longitudinal waves.
• Particles vibrate parallel to wave direction.
• Creates compressions, rarefactions.
• Speed varies: fastest solids, slowest gases.
• Human audible range: 20Hz to 20,000Hz.
• Below range: infrasound.
• Above range: ultrasound.
• Ultrasound used in medical imaging, cleaning.