maxwell equations + scalar and vector potentials

[JamesGoh]

Im doing some study on scalar and vector potentials in the area of electromagnetics, and the author of the book derived this equation

\vec{E} = -j\omega\vec{A} - \nabla\phi

where \vec{A} = vector potential and

\phi = scalar potential and

\vec{E} = time harmonic form of electric field

The author goes on to make a statement saying this may be a familiar result, however Im not sure exactly what he is referring to ?? Can anyone shed some light ?

[CompuChip]

Looks like one of these (http://en.wikipedia.org/wiki/Maxwell_equations#Potentials).
What is j, is it \sqrt{-1}? Is a specific vector potential given (say, A \propto e^{-j \omega t}?)

[clem]

The author probably assumes you have read an intermediate level EM textbook.

[JamesGoh]

Looks like one of these (http://en.wikipedia.org/wiki/Maxwell_equations#Potentials).
What is j, is it \sqrt{-1}? Is a specific vector potential given (say, A \propto e^{-j \omega t}?)


j = sqrt(-1). The textbook assumes a general vector potential (where at this stage only the curl of the vector potential has been defined)

[CompuChip]

Well, as I said, the Maxwell equations contain
\vec E = \frac{\partial \vec A}{\partial t} - \vec\nabla\phi
so if A is something like \vec A = \vec A_0 e^{-j\omega t} then you would get what you posted. That's all I can guess based on your information,

[JamesGoh]

Sorry, didn't notice your wikipedia link. Will look into it and get back to you !

[kof9595995]

i'm not quite sure about what j and omega presents,but the formula seems to be written in the form that satisfy helmhotlz's theorem,hope it help...