Chapter 13. Sound wave intensity in terms of displacement amplitude A (13-29)

Question

I0ODsB/JtbEJyaEQ3jSbeivMBtSXR8cIIIt8zD5LOYXwbbRqjpHfllqhB4E=
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Question

3iGtWs7rexX3USNVoGOhCKzOI04eJfEDv0D6oW1yt74ZvVseUt98IkAB8Ob+KBqYJJOK+Si68lUxvaba
{"title":"Intensity of a sound wave","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"rect\",\"coords\":\"1,19,16,60\"}]"} {"title":"Density of the wave medium (usually air)","description":"Correct!","type":"correct","color":"#ffcc00","code":"[{\"shape\":\"rect\",\"coords\":\"89,32,114,67\"}]"} {"title":"Displacement amplitude of the wave","description":"Incorrect","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"261,25,282,57\"}]"} {"title":"Angular frequency of the wave","description":"Wrong","type":"incorrect","color":"#000080","code":"[{\"shape\":\"rect\",\"coords\":\"210,32,239,57\"}]"} {"title":"Speed of sound waves in the medium","description":"Incorrect","type":"incorrect","color":"#993300","code":"[{\"shape\":\"rect\",\"coords\":\"114,34,133,56\"}]"}

Question

XcbmFO8Jde/Rg9f59G+GENZ2gMfvGkVrBF13Vd3TwPgizBY9Xd90MGCHiSneaj3a
{"title":"Intensity of a sound wave","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"rect\",\"coords\":\"1,19,16,60\"}]"} {"title":"Density of the wave medium (usually air)","description":"Incorrect","type":"incorrect","color":"#ffcc00","code":"[{\"shape\":\"rect\",\"coords\":\"89,32,114,67\"}]"} {"title":"Displacement amplitude of the wave","description":"Incorrect","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"261,25,282,57\"}]"} {"title":"Angular frequency of the wave","description":"Correct!","type":"correct","color":"#000080","code":"[{\"shape\":\"rect\",\"coords\":\"210,32,239,57\"}]"} {"title":"Speed of sound waves in the medium","description":"Incorrect","type":"incorrect","color":"#993300","code":"[{\"shape\":\"rect\",\"coords\":\"114,34,133,56\"}]"}

Question

x9VdNA9daI7ms8ni6LQs1QvrQI9JrUNM/at24qBpP29WwEzZblzocnRJPAxs8k3fBzE0AQ==
{"title":"Intensity of a sound wave","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"rect\",\"coords\":\"1,19,16,60\"}]"} {"title":"Density of the wave medium (usually air)","description":"Incorrect","type":"incorrect","color":"#ffcc00","code":"[{\"shape\":\"rect\",\"coords\":\"89,32,114,67\"}]"} {"title":"Displacement amplitude of the wave","description":"Correct!","type":"correct","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"261,25,282,57\"}]"} {"title":"Angular frequency of the wave","description":"Wrong","type":"incorrect","color":"#000080","code":"[{\"shape\":\"rect\",\"coords\":\"210,32,239,57\"}]"} {"title":"Speed of sound waves in the medium","description":"Incorrect","type":"incorrect","color":"#993300","code":"[{\"shape\":\"rect\",\"coords\":\"114,34,133,56\"}]"}

Question

b9GKymliutYfaKgM3dx3J1bAOPLBiMbbJCoY7x0L55uTYm+iCjXuoOH/m1lBDmCxVRkx4Q==
{"title":"Intensity of a sound wave","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"rect\",\"coords\":\"1,19,16,60\"}]"} {"title":"Density of the wave medium (usually air)","description":"Incorrect","type":"incorrect","color":"#ffcc00","code":"[{\"shape\":\"rect\",\"coords\":\"89,32,114,67\"}]"} {"title":"Displacement amplitude of the wave","description":"Wrong","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"261,25,282,57\"}]"} {"title":"Angular frequency of the wave","description":"Wrong","type":"incorrect","color":"#000080","code":"[{\"shape\":\"rect\",\"coords\":\"210,32,239,57\"}]"} {"title":"Speed of sound waves in the medium","description":"Correct!","type":"correct","color":"#993300","code":"[{\"shape\":\"rect\",\"coords\":\"114,34,133,56\"}]"}

Review

Equation 13-28 says that the power associated with the wave is proportional to the square of the wave amplitude \(A\). This turns out to be a general attribute of waves of all kinds, not just sound waves. Note also that the power is proportional to \(L^2\), which is the cross-sectional area through which the wave energy passes. The power \(\textit{divided}\) by the cross-sectional area \(L^2\) is called the \(\textbf{intensity}\) of \(I\) of the wave, measured in watts per square meter (\(\mathrm{W}/\mathrm{m}^2\)). From Equation 13-28, this is