Sound Waves
As you already know sound is a type of longitudinal wave. A longitudinal wave is bits of squashed and stretched air, it is represented like this:
This isn't the way sound ways are known for looking, this is because it is really difficult to represent longitudinal waves on a screen and it's hard to measure from. However, we know how to solve both of these problems, you take the rarefaction points and turn them into troughs and the compression points and turn them to peaks, this creates a transverse wave. Now we can measure the waves and show them on a screen such as an oscilloscope.
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On an oscilloscope shows the sound waves as a transverse wave, when a sound is played through it the wave forms on the screen, it can have many shapes to the wave all of which are different because of the pitch and volume of the noise.
The LOUDER the noise- The bigger the amplitude.
The QUIETER the noise- The smaller the amplitude.
The HIGHER the pitch- The bigger the wavelength.
The LOWER the pitch- The smaller the wavelength.
The QUIETER the noise- The smaller the amplitude.
The HIGHER the pitch- The bigger the wavelength.
The LOWER the pitch- The smaller the wavelength.
REMEMBER:
- The amplitude is the distance between the rest position to either a peak or trough.
- The wavelength is the distance from either a peak or trough to the next consecutive peak or trough.
Waves in music.
When you see a wave diagram the wave shape is very regular but if you were to see a diagram of a musical note to be played through a oscilloscope it would appear distorted. This is because the note of the instrument is different for every other instrument, this means that all waves of an instrument are different, it looks like this:
Every color represents a different instrument, they all have the same amplitude, wavelength and frequency but are distorted at regular intervals.