Sound waves

Sound Wave

A mechanical, longitudinal wave that travels through a medium via vibrations of particles.

Medium Requirement

Sound requires a physical medium such as a solid, liquid, or gas to travel and cannot propagate through a vacuum.

Speed of Sound

The velocity at which sound travels; it is fastest in solids, intermediate in liquids, and slowest in gases due to particle density.

Pitch

The human perception of the frequency of a sound wave; higher frequencies are perceived as higher pitches.

Loudness

The human perception of the amplitude of a sound wave, typically measured using the decibel (dB) scale.

Echo

A sound caused by the reflection of sound waves from a surface back to the listener.

Ultrasound

Sound waves with a frequency greater than the upper limit of human hearing, which is approximately 20,000\text{ Hz}.

Infrasound

Sound waves with a frequency below the lower limit of human hearing, which is approximately 20\text{ Hz}.

Doppler Effect

The shift in frequency of a wave in relation to an observer who is moving relative to the wave source.

Human Hearing Range

The range of frequencies, typically from 20\text{ Hz} to 20,000\text{ Hz}, that can be detected by the human ear.