Density of the wave medium (usually air)
{"title":"Intensity of a sound wave","description":"Incorrect","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"rect\",\"coords\":\"1,67,27,115\"}]"} {"title":"Pressure amplitude of the wave","description":"Wrong","type":"incorrect","color":"#ffcc00","code":"[{\"shape\":\"rect\",\"coords\":\"122,29,151,77\"}]"} {"title":"Speed of sound waves in the medium","description":"Wrong","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"155,122,183,156\"}]"} {"title":"Density of the wave medium (usually air)","description":"Correct!","type":"correct","color":"#000080","code":"[{\"shape\":\"rect\",\"coords\":\"116,117,152,166\"}]"}Equation 13-29 is expressed in terms of the displacement amplitude A. However, our ears are more directly sensitive to the pressure variations in a sound wave. The displacement amplitude A in a sound wave is related to the pressure amplitude pmax, or maximum pressure variation, by
(13-30) A=pmaxρvsoundω
If we substitute Equation 13-30 for A into Equation 13-29, we get an alternative expression for the intensity of a sound wave:
I=12ρvsoundω2(pmaxρvsoundω)2=p2max2ρvsoundω2ρ2v2soundω2
or, simplifying,