Chapter 22. Electric energy density (22-14)

Question

bSIXjOefito08N4UNAxWTKPlwBnO53kBWYYX9Q==
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Question

Q4oipdn96VapCbbhTzlAaM4nrMshCjs8N4LNQQ==
{"title":"Electric 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\":\"1,51,34,85\"}]"} {"title":"Electric field magnitude","description":"Correct!","type":"correct","color":"#008000","code":"[{\"shape\":\"rect\",\"coords\":\"232,29,272,77\"}]"} {"title":"Permittivity of free space","description":"Incorrect","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"183,40,214,81\"}]"}

Question

vBkI+Vt8MfnYrBL3sYTzTrVSmjHBcILzDs8PMOotkU0=
{"title":"Electric 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\":\"1,51,34,85\"}]"} {"title":"Electric field magnitude","description":"Incorrect","type":"incorrect","color":"#008000","code":"[{\"shape\":\"rect\",\"coords\":\"232,29,272,77\"}]"} {"title":"Permittivity of free space","description":"Correct!","type":"correct","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"183,40,214,81\"}]"}

Review

Equation 22-14 says that wherever there is an electric field, there is energy. This motivates the idea that the energy stored in a capacitor is stored in the field itself. We derived Equation 22-14 for the special case of a parallel-plate capacitor, but it turns out to be valid in any situation where an electric field is present.