Electric Dipole Field: Difference & Coordinates

AI Thread Summary
The discussion focuses on the coordinate systems used for electric dipole formulas and the distinction between pure and physical dipoles. It clarifies that the origin of the Cartesian system is often placed at the midpoint of the dipole moment vector to simplify mathematical derivations, although it can technically be placed anywhere. Participants emphasize that the difference between real and ideal dipoles parallels the general distinction between real and ideal entities. Understanding these concepts is essential for accurate application in physics. The conversation highlights the importance of specifying the coordinate system in dipole calculations.
Septim
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Greetings,

I wonder with respect to what coordinates the formulas given for the electric dipole is valid. Also I want to comprehend the difference between pure and physical dipoles and why many books put the origin of the cartesian system they define on the middle point of the electric dipole moment vector( I think they should put the origin at the tail of the vector). Any insight is welcome.

Thanks in advance,
 
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Septim said:
Greetings,

I wonder with respect to what coordinates the formulas given for the electric dipole is valid.
Whatever coordinate system the formulas are given in of course. You need to be specific.
Also I want to comprehend the difference between pure and physical dipoles and why many books put the origin of the cartesian system they define on the middle point of the electric dipole moment vector( I think they should put the origin at the tail of the vector). Any insight is welcome.
The books are putting the origin half-way between the charges not the dipole vector - which can be drawn anywhere. They put the origin there to make the math/derivations simpler. You can put the origin anyplace you like.

The difference between real and "pure" or ideal dipoles is the same as real vs ideal anything.
Also see:
https://www.physicsforums.com/showthread.php?t=222675
 
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