BASIC TERMS RELATED TO WAVES
To study waves, we comes across various terms amplitude, wavelength. Show a graph for sound pressure verses time. Sound pressure swing about normal (atmosphere pressure) in a region as rarefaction follows compression. Sound pressure has its highest value at the middle of a compression and lowest value at the middle of a rarefaction.
Sound pressure verses time graph for sound waves
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AMPLITUDE
The maximum displacement of the vibrating object from it mean position is called its AMPLITUDE. It is measured in the unit meter (M). For the wave with large amplitude the sound will be louder.
Amplitude
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WAVELENGTH
Wavelength is the distance between the centres of the compressions rarefaction of two consecutive wave. In point B and F are the centres of two adjacent compression. The distance between B and F is equal to wavelength of the wave. The wavelength of a wave is measured in meter (M). It is represent by the symbol of Y (pronounced as Lambda). Similarly point D and H are the centres of two adjacent rarefaction. Thus the distance between D and H is also equal to the wavelength Y of the wave. It is to be noted the distance between the points A and E as well as C and G are also equal the wavelength of the wave.
Wavelength
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Collected data from my book of science. Photos from there given source.