Sound as Communication
sound is a useful and versatile form of communication
What makes sound so advantageous for communication?
- Sound does not need light in order to be heard.
- Sound can travel through solids, liquids and gases.
This means that sound can be used in dense environments.
So how is sound energy produced?
Sound is produced by a vibrating object. These vibrations cause compressions (areas of high density) and rarefactions (areas of low density) in the air particles adjacent to the source of the vibrations.
What is "frequency"?
Frequency is the speed in which the vibrations move through a medium. It is measured in Hertz (Hz).
The vibrations produced by different organisms result in the same frequency of vibrations in the medium it is travelling through.
For example, if you say "Biology" at 80 Hz, this will result in the vibrations produced by saying that word to travel through the air (the medium) at 80 Hz.
How do we see sound?
The series of compressions and rarefactions caused by sound vibrations can be measured by an oscilloscope.
The oscilloscope measures frequency and amplitude and displays this as a graph.
Peaks in the graph correspond to areas of highest compression.
What is the relationship between Frequency, Wavelength and Pitch?
A soundwave has a repeating pattern of high pressure and low pressure regions. The distance between one area of high pressure and the next, is the wavelength.
A sound with a long wavelength has a low frequency and therefore a low pitch.
As the wavelength gets shorter, the frequency gets higher.