Properties of sound waves: Waves

Sound wave

Longitudinal waves that cause particles to vibrate parallel to the direction of wave travel

Medium

A material through which a wave can be transmitted

Mediums that sound can travel through

Sound can travel through solids, liquids and gases

Speed of sound

Depends on the medium that the sound is travelling through

Speed of sound in air

Approx. 330 metres per second (m/s)

Speed of sound in a vacuum

Sound cannot travel through a vacuum because it needs particles to vibrate

How the ear allows sounds to be heard

Sound waves cause the ear drum and other parts to vibrate which causes the sensation of sound

Frequency of a sound wave

Related to the pitch of a sound

Relationship between frequency and pitch

The higher the frequency, the higher the pitch

Amplitude of a sound wave

Related to the loudness of a sound

Relationship between amplitude and loudness

The higher the amplitude, the louder the sound

Range of human hearing

20 Hz to 20,000 Hz

Ultrasound

Sound waves that have a frequency higher than the upper limit for human hearing (above 20,000 Hz)

Infrasound

Sound waves that have a frequency lower than the lower limit for human hearing (below 20 Hz)