Chapter 22. Magnetic energy density (22-19)

Question

G7QAHiOsKLlKXckRHOaejxSuC62yVGdpz9YwxQ==
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Question

Xcxiq520KvaCQJTemICTUnmH+NW1dVCLecr6N4rHBpA=
{"title":"Magnetic energy density","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"poly\",\"coords\":\"144,22\"},{\"shape\":\"rect\",\"coords\":\"1,70,34,104\"}]"} {"title":"Magnetic field magnitude","description":"Correct!","type":"correct","color":"#008000","code":"[{\"shape\":\"rect\",\"coords\":\"150,29,190,77\"}]"} {"title":"Permeability of free space","description":"Incorrect","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"164,109,207,153\"}]"}

Question

o0vUgplvuKeoxdMa0Flg83dbvfBb+yGlj8EjtJQs+SY=
{"title":"Magnetic energy density","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"poly\",\"coords\":\"144,22\"},{\"shape\":\"rect\",\"coords\":\"1,70,34,104\"}]"} {"title":"Magnetic field magnitude","description":"Incorrect","type":"incorrect","color":"#008000","code":"[{\"shape\":\"rect\",\"coords\":\"150,29,190,77\"}]"} {"title":"Permeability of free space","description":"Correct!","type":"correct","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"164,109,207,153\"}]"}

Review

Just as Equation 22-14 tells us that there is electric energy wherever there is an electric field, Equation 22-19 tells us that there is magnetic energy wherever there is a magnetic field. This is true for an inductor, so we can think of the energy stored in a current-carrying inductor as being stored in the magnetic field within the inductor. But Equation 22-19 is valid wherever there is a magnetic field.