Definition:
An Audible Frequency (AF) is characterized as a periodic vibration whose frequency is audible to the average human. The SI unit of audio frequency is the hertz (Hz). It is the property of sound that most determines pitch.
There are two different types of the frequency ranges
Infrasonic Range:
In audible sound waves whose frequencies are less than 20 Hz are in the infrasonic range. Sources of infrasonic waves include earthquakes, thunder, volcanoes and waves produces by vibrating heavy machinery. The hearing ranges of elephants and whales extend into the infrasonic region.Examples:
Earthquakes, thunder lightenning - these sounds less than 20 Hz
Ultrasonic Range:
Frequencies above 20,000 Hz are in the ultrasonic range. The audible range of dogs, cats, moths and mice extends into ultrasound frequencies. They can hear very high frequencies that humans cannot.
Examples:
Rhinosers, Whales - These can here above 20,000 Hz frequency range.
Audible Frequency Range Examples:
Figure: Human audible frequency range is 20 Hz to 20,000 Hz.
Figure: Sound frequency of the sun is 126.22Hz
Figure: Sound frequency of the train horn is 30 Hz to 200 Hz
Figure: Sound frequency of the plane ranges between 50 Hz to 5000 Hz