In physics, the electric dipole moment is a measure of the polarity of a system of electric charges. We define the electric dipole moment p (also called the electric dipole), which has charges +q and -q, and with r, the vector from the negative to the positive charge as Image File history File links Solenoid. ... Electromagnetism is the physics of the electromagnetic field: a field which exerts a force on particles that possess the property of electric charge, and is in turn affected by the presence and motion of those particles. ... Lightning strikes during a night-time thunderstorm. ... It has been suggested that this article or section be merged with magnet. ... Electrostatics (also known as Static Electricity) is the branch of physics that deals with the forces exerted by a static (i. ... Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. ... Coulombs torsion balance In physics, Coulombs law is an inverse-square law indicating the magnitude and direction of electrostatic force that one stationary, electrically charged object of small dimensions (ideally, a point source) exerts on another. ... It has been suggested that optical field be merged into this article or section. ... In physics and mathematical analysis, Gausss law is the electrostatic application of the generalized Gausss theorem giving the equivalence relation between any flux, e. ... This article or section does not cite any references or sources. ... Magnetostatics is the study of static magnetic fields. ... In physics, Ampères Circuital law, discovered by André-Marie Ampère, relates the circulating magnetic field in a closed loop to the electric current passing through the loop. ... This template is misplaced. ... Magnetic flux, represented by the Greek letter Φ (phi), is a measure of quantity of magnetism, taking account of the strength and the extent of a magnetic field. ... The Biot-Savart law is a physical law with applications in both electromagnetics and fluid dynamics. ... A bar magnet. ... Classical electrodynamics (or classical electromagnetism) is a theory of electromagnetism that was developed over the course of the 19th century, most prominently by James Clerk Maxwell. ... Electric current is the flow (movement) of electric charge. ... Lorentz force. ... Electromotive force (emf) is the amount of energy gained per unit charge that passes through a device in the opposite direction to the electric field existing across that device. ... Electromagnetic induction is the production of an electrical potential difference (or voltage) across a conductor situated in a changing magnetic flux. ... Faradays law of induction (more generally, the law of electromagnetic induction) states that the induced emf (electromotive force) in a closed loop equals the negative of the time rate of change of magnetic flux through the loop. ... Displacement current is a quantity related to a changing electric field. ... In electromagnetism, Maxwells equations are a set of equations first presented as a distinct group in the later half of the nineteenth century by James Clerk Maxwell. ... The electromagnetic field is a physical field that is produced by electrically charged objects and which affects the behaviour of charged objects in the vicinity of the field. ... Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields. ... This article or section does not adequately cite its references or sources. ... Electrical conduction is the movement of electrically charged particles through a transmission medium (electrical conductor). ... Electrical resistance is a measure of the degree to which an electrical component opposes the passage of current. ... Capacitance is a measure of the amount of electric charge stored (or separated) for a given electric potential. ... Inductance (or electric inductance) is a measure of the amount of magnetic flux produced for a given electric current. ... Electrical impedance, or simply impedance, is a measure of opposition to a sinusoidal alternating electric current. ... A resonator is a device or part that vibrates (or oscillates) with waves. ... It has been suggested that this article or section be merged with Waveguide (optics). ... The first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density Physics (Greek: (phúsis), nature and (phusiké), knowledge of nature) is the branch of science concerned with the discovery and characterization of universal laws which govern matter, energy, space, and time. ... The polarity of an object is, in general, its physical alignment of atoms. ... Electric charge is a fundamental property of some subatomic particles, which determines their electromagnetic interactions. ...

Note that since r is a vector with a certain direction, so is p. Simplistically here it points from negative charge to positive charge.

Because it is often convenient to be able to treat complex configurations of electric charge by how much their behaviour resembles a dipole, we generalize our definitions as follows: in cases where one wishes to find the electric dipole moment of some configuration of N discrete charges, each is a vector from some origin to q_i with magnitude equal to the charge of q_i The Earths magnetic field, which is approximately a dipole. ...

(Note this definition simplifies to the basic dipole for N = 2 and charges of q+ and q-, see Vector (spatial)) This can be carried over to an integral in the case of a continuous distribution of charges A vector going from A to B. In physics and in vector calculus, a spatial vector, or simply vector, is a concept characterized by a magnitude and a direction. ...

The dipole moment is most commonly used for systems which have an overall neutral charge. For example, a pair of opposite charges, or a neutral conductor in a uniform electric field. For such systems, the value of the electric dipole moment is independent of the origin of the axis system. For non-neutral systems, a dependence on the choice of origin arises. In order retain the electric dipole moment's utility in calculating the torque on a dipole as well as other uses, the origin is often taken to be the center of absolute charge, , for the system, which is defined like the center of mass and is, for some systems, the same. The Earths magnetic field, which is approximately a dipole. ... In physics, the center of mass of a system of particles is a specific point at which, for many purposes, the systems mass behaves as if it were concentrated. ...

for the discrete case, or for the continous case is then taken relative to the origin indicated by .

See also

• Magnetic dipole moment
• Bond dipole moment
• Electron electric dipole moment

In physics, the magnetic moment of an object is a vector relating the aligning torque in a magnetic field experienced by the object to the field vector itself. ... The bond dipole moment is a measure of how polar a bond is within a molecule. ... There are very few or no other articles that link to this one. ...

External links

• Electric Dipole Moment -- from Eric Weisstein's World of Physics