Dipole and Quadrupole moments and axial symmetry

lapantufla
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Homework Statement
Show that if the charge (or current) distribution has axial symmetry then the electric (or magnetic) dipole moment is null.
Show that the quadrupole moments Qij with i different from j are null under the same conditions.
Relevant Equations
Electric Dipole Moment Equation.
Magnetic Dipole Moment Equation.
Quadrupole Moment Equation.
Hello, I would like to find a mathematical demonstration of this problem. While I have always used it, I could never prove it. Given a charge or current distribution with axial symmetry the electric and magnetic dipole moment are null:

mde.png
(electric dipole moment)

mdm.png
(magnetic dipole moment)and that the elements outside the diagonal of the quadrupole moment are also canceled:

qm.png
(Quadrupole moment)From already thank you very much. (excuse my English, I use a translator).
 
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Hello lapantufla, :welcome: !

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lapantufla said:
Homework Statement:: Show that if the charge (or current) distribution has axial symmetry then the electric (or magnetic) dipole moment is null.
Seems to me something was lost in translation: even the simplest dipole example has axial symmetry.

re lapantufla: does it have a meaning in your language ?
 
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