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Echoes and sonar - CCEAProperties of sound

Sound is caused by the vibration of particles but not all vibrations can be heard as sound. Common ideas about sound come from the limited range of vibrations that human ears can detect.

Part of Combined ScienceWaves

Properties of sound

The of a sound wave is related to the that is heard:

  • high frequency sound waves are high pitched;
  • low frequency sound waves are low pitched.

The of a sound wave is related to the volume of the sound:

  • high amplitude sound waves are loud;
  • low amplitude sound waves are quiet.
Trace one: peak heights half unit, peak to peak distance 1.5 units. Trace two: peak heights one unit, peak to peak distance 1.5 units. Trace three: peak heights one unit, peak to peak one unit.

traces showing the following sounds:

  1. quiet, low pitch sound
  2. loud, low pitch sound
  3. loud, high pitch sound

The is only stimulated by a limited range of frequencies.

This means that humans can only hear certain frequencies.

The range of normal human hearing is 20 Hz to 20,000 Hz (or 20 Hz to 20 kHz).