So, what does this mean for the physical interpretation of a point dipole?

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A point dipole is defined as a dipole whose size is negligible compared to the distances involved in the problem, meaning all relevant distances are much larger than the separation between the charges. This interpretation allows for the dipole moment to remain finite while the charge approaches infinity as the distance between the charges tends to zero. However, it does not imply that the distance is infinitely small; rather, the charge remains finite in practical applications. Examples include scenarios where the dipole's influence is considered at large distances, such as in electromagnetic fields. Understanding this concept is crucial for accurately modeling physical systems involving dipoles.
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Mathematically,its easy to say that when the distance between the points tends to zero,for the dipole moment to stay finite,the charge should tend to infinity.
My question is,how should I interpret it?
What is a point dipole physically?
Could you give examples?
thanks
 
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You can interpret it as a dipole which is so small that its size does not matter. This implies that all relevant distances in your problem are much larger than the size of the dipole, and higher moments (quadrupole, ...) do not matter.
 
Shyan said:
...for the dipole moment to stay finite,the charge should tend to infinity.

When we say a point dipole we mean that the distance at which are calculating electric field is much greater than the distance between the charges .

eg 1cm is very small before 10km

But it does not mean that the distance itself is infinitely small. Hence charge would also be finite.
 
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