What is the Difference Between Electric Dipole and Magnetic Dipole

The key difference between electric dipole and magnetic dipole is that there are two equal and opposite charges in an electric dipole with separate existence, whereas a magnetic dipole has two equal and unlike poles that do not have a separate existence.

Electric dipole and magnetic dipole are two types of dipole moments that are analogous to each other.

1. Overview and Key Difference
2. What is an Electric Dipole
3. What is a Magnetic Dipole
4. Electric Dipole vs Magnetic Dipole in Tabular Form
5. Summary – Electric Dipole vs Magnetic Dipole

What is an Electric Dipole?

An electric dipole can be described as a couple of opposite charges, “q” and “-q,” that are separated by a distance of “d.” The direction of these electric dipoles in the space can always be given as negative charge “-q” to the positive charge “q.” Therefore, the midpoint “q” and “-q” can be named the center of the dipole.

An example of the most simple electric dipole type can be given as a pair of electric charges of two opposite signs that are in equal magnitude and separated by distance. We can visualize an electric dipole using two charges of equal magnitude “q” that are separated by a distance “d” where the first charged particle is positively charged and the second charged particle is negatively charged. This combination is an electric dipole. The denotation of an electric dipole can be done by the symbol “p.” This electric dipole can be described as the product of the magnitude of the charges that are multiplied by the distance between them.

Moreover, an electric dipole moment is a vector quantity. This has a defined direction that comes from the negative charge towards the positive charge. It is significant to remember the fact that this convention of direction is usually followed in physics, but in chemistry, the convention is taken as opposed to this (from positive to negative). We call the line along the direction of an electric dipole the axis of the dipole.

What is a Magnetic Dipole?

A magnetic dipole can be described as a system of a magnetic north pole and a magnetic south pole separated by a small distance. A magnetic dipole is the limitation of either a closed loop of electric current. Or else it is a pair of poles as the size of the source gets reduced to zero upon keeping the magnetic moment constant. This dipole can be given as the magnetic analog of the electric dipole.

A true magnetic monopole has never been observed in nature, but magnetic monopole quasiparticles can be observed as emergent properties of some condensed matter systems. Furthermore, one form of magnetic dipole moment can be observed with a fundamental quantum property named “spin” of elementary particles. Magnetic monopoles do not exist; thus, the magnetic field that occurs at a large distance from any static magnetic source appears as the field of a dipole having the same dipole moment.

What is the Difference Between Electric Dipole and Magnetic Dipole?

Electric dipole and magnetic dipole are two types of dipole moments that are analogous to each other. The key difference between electric dipole and magnetic dipole is that an electric dipole has two equal and opposite charges, having separate existence, whereas a magnetic dipole has two equal and unlike poles that do not have a separate existence. Moreover, an electric dipole is made of two electric monopoles, while a magnetic dipole is the most elementary element.

Below is a summary of the difference between electric dipole and magnetic dipole in tabular form for side-by-side comparison.

Summary – Electric Dipole vs Magnetic Dipole

An electric dipole can be described as a couple of opposite charges, “q” and “-q,” that are separated by a distance “d.” A magnetic dipole can be described as a system of magnetic north pole and a magnetic south pole separated by a small distance. The key difference between electric dipole and magnetic dipole is that there are two equal and opposite charges in an electric dipole with separate existence, whereas a magnetic dipole has two equal and unlike poles that do not have a separate existence.

Reference:

1. “Electric Dipole – Definition, Formula, Units, Magnitude.” BYJUS, 7 Sept. 2022.

Image Courtesy:

1. “Electric-dipole-3D” By MikeRun – Own work, field lines imported from (CC BY-SA 4.0) via Commons Wikimedia
2. “VFPt dipole electric” By Geek3 – Own work (CC BY-SA 3.0) via Commons Wikimedia