What is meant by a 'point dipole' ? Also?explain the meaning of this line(NCERTpg 29-- 1st para) -- "when the dipole size 2a approaches zero, the charge q approaches infinity in such a way that the product p= q x 2ais finite. such a dipole is referred to as point dipole." [DON'T PROVIDE LINKS PLEASE]
Dear Student,
In a point dipole , the distance between the charges is much smaller than all the relevant distances. Example : 1 cm compared to 1 km. Also, the charges should very large but finite to keep the moment finite.
When the dipole size 2a approaches zero, the charge q approaches infinity in such a way that the product p= q x 2a is finite. In this case, we talk about the limit of dipole and we know that the product of infinity and zero have always a finite value. Thatswhy the product p = q x 2a is finite. Such a dipole is referred to as point charge.
Regards
In a point dipole , the distance between the charges is much smaller than all the relevant distances. Example : 1 cm compared to 1 km. Also, the charges should very large but finite to keep the moment finite.
When the dipole size 2a approaches zero, the charge q approaches infinity in such a way that the product p= q x 2a is finite. In this case, we talk about the limit of dipole and we know that the product of infinity and zero have always a finite value. Thatswhy the product p = q x 2a is finite. Such a dipole is referred to as point charge.
Regards