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Dipole (other)
In physics, a dipole is a quantity involving some form of polarity. Dipole may also refer to: In physics *Electric dipole *Magnetic dipole * Dipole moment (other) *A flow dipole, a separation of a sink and a source in potential flow In meteorology *Arctic dipole anomaly *Indian Ocean Dipole *Subtropical Indian Ocean Dipole Other uses *Dipole antenna, a type of radio antenna *Dipole magnet, a permanent magnet *Dipole graph, a graph with two poles *Dipole speaker, a loudspeaker enclosure *Dipole model of the Earth's magnetic field, a first order approximation of the rather complex true Earth's magnetic field (which can be viewed as dipolar) * Dipole anisotropy, the progressive difference in the frequency of radiation from opposite directions due to the motion of the observer relative to the source * Dipole–dipole attraction, one of several intermolecular forces See also * Monopole (other) * Quadrupole * Multipole expansion A multipole expansion is a mathematica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole
In physics, a dipole () is an electromagnetic phenomenon which occurs in two ways: *An electric dipole deals with the separation of the positive and negative electric charges found in any electromagnetic system. A simple example of this system is a pair of charges of equal magnitude but opposite sign separated by some typically small distance. (A permanent electric dipole is called an electret.) *A magnetic dipole is the closed circulation of an electric current system. A simple example is a single loop of wire with constant current through it. A bar magnet is an example of a magnet with a permanent magnetic dipole moment. Dipoles, whether electric or magnetic, can be characterized by their dipole moment, a vector quantity. For the simple electric dipole, the electric dipole moment points from the negative charge towards the positive charge, and has a magnitude equal to the strength of each charge times the separation between the charges. (To be precise: for the definition of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole Graph
In graph theory, a dipole graph, dipole, bond graph, or linkage, is a multigraph consisting of two vertices connected with a number of parallel edges. A dipole graph containing edges is called the dipole graph, and is denoted by . The dipole graph is dual to the cycle graph . The honeycomb as an abstract graph is the maximal abelian covering graph of the dipole graph , while the diamond crystal as an abstract graph is the maximal abelian covering graph of . Similarly to the Platonic graphs, the dipole graphs form the skeletons of the hosohedra. Their duals, the cycle graphs, form the skeletons of the dihedra A dihedron is a type of polyhedron, made of two polygon faces which share the same set of ''n'' edges. In three-dimensional Euclidean space, it is degenerate if its faces are flat, while in three-dimensional spherical space, a dihedron with flat .... References * * Jonathan L. Gross and Jay Yellen, 2006. ''Graph Theory and Its Applications, 2nd Ed.'', p. 17. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrupole
A quadrupole or quadrapole is one of a sequence of configurations of things like electric charge or current, or gravitational mass that can exist in ideal form, but it is usually just part of a multipole expansion of a more complex structure reflecting various orders of complexity. Mathematical definition The quadrupole moment tensor ''Q'' is a rank-two tensor—3×3 matrix. There are several definitions, but it is normally stated in the traceless form (i.e. Q_ + Q_ + Q_ = 0). The quadrupole moment tensor has thus nine components, but because of transposition symmetry and Trace (linear algebra), zero-trace property, in this form only five of these are independent. For a discrete system of \ell point charges or masses in the case of a Quadrupole#Gravitational quadrupole, gravitational quadrupole, each with charge q_\ell, or mass m_\ell, and position \vec_\ell = \left(r_, r_, r_\right) relative to the coordinate system origin, the components of the ''Q'' matrix are defined by: : ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monopole (other)
Monopole may refer to: * Magnetic monopole, or Dirac monopole, a hypothetical particle that may be loosely described as a magnet with only one pole * Monopole (mathematics), a connection over a principal bundle G with a section (the Higgs field) of the associated adjoint bundle * ''Monopole'', the first term in a multipole expansion * Monopole (wine), an appellation owned by only one winery * ''Monopole'' (album), a 2011 album by White Town * Monopole antenna, a radio antenna that replaces half of a dipole antenna with a ground plane at right-angles to the remaining half * Monopole, a tubular self-supporting telecommunications mast * ''The Monopole'', a bar in Plattsburgh, NY * Établissements Monopole, a French auto parts manufacturer, racing car builder and racing team. See also * Dipole, a particle with a north and south pole * Dyon, a particle with electric and magnetic charge * Instanton, a class of field solutions that includes monopoles * Monomial, a polynomial which ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole–dipole Attraction
An intermolecular force (IMF) (or secondary force) is the force that mediates interaction between molecules, including the electromagnetic forces of attraction or repulsion which act between atoms and other types of neighbouring particles, e.g. atoms or ions. Intermolecular forces are weak relative to intramolecular forces – the forces which hold a molecule together. For example, the covalent bond, involving sharing electron pairs between atoms, is much stronger than the forces present between neighboring molecules. Both sets of forces are essential parts of force fields frequently used in molecular mechanics. The investigation of intermolecular forces starts from macroscopic observations which indicate the existence and action of forces at a molecular level. These observations include non-ideal-gas thermodynamic behavior reflected by virial coefficients, vapor pressure, viscosity, superficial tension, and absorption data. The first reference to the nature of microscopic force ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole Anisotropy
Dipole anisotropy is a form of anisotropy and the progressive difference in the frequency of radiation from opposite directions due to the motion of the observer relative to the source. As a result of that motion, one end of the 360-degree spectrum is redshifted, whereas the other end is blueshifted. That effect is notable in measurements of the cosmic microwave background radiation, due to the motion of the Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa .... Physical cosmology {{Physical-cosmology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole Model Of The Earth's Magnetic Field
The dipole model of the Earth's magnetic field is a first order approximation of the rather complex true Earth's magnetic field. Due to effects of the interplanetary magnetic field (IMF), and the solar wind, the dipole model is particularly inaccurate at high L-shells (e.g., above L=3), but may be a good approximation for lower L-shells. For more precise work, or for any work at higher L-shells, a more accurate model that incorporates solar effects, such as the Tsyganenko magnetic field model, is recommended. Formulation The following equations describe the dipole magnetic field. First, define B_0 as the mean value of the magnetic field at the magnetic equator on the Earth's surface. Typically B_0=3.12\times10^\ \textrm. Then, the radial and latitudinal fields can be described as :B_r = -2B_0\left(\frac\right)^3\cos\theta :B_\theta = -B_0\left(\frac\right)^3\sin\theta :, B, = B_0\left(\frac\right)^3 \sqrt where R_E is the mean radius of the Earth (approximately 6370&n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole Speaker
A dipole speaker enclosure in its simplest form is constructed by mounting a loudspeaker driver on a flat panel. The panel may be folded to conserve space. The term dipole derives from the fact that the polar response consists of two lobes, with equal radiation forwards and backwards, and none perpendicular to the axis. (By comparison a ''monopole'' response consists of one lobe.) This can be useful in reducing the stimulation of resonant room modes at low frequencies. It also results in high frequencies being reflected from any rear wall, which can enhance the naturalness of the sound in typical listening rooms by creating more diffuse reverberation, though in theory it could detract from stereo localization. For this reason dipole speakers are often used as surround channel speakers, where a diffuse sound is desired to create ambience. A dipole speaker works by creating air movement (as sound pressure waves) directly from the front and back surfaces of the driver, rather ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole Magnet
A dipole magnet is the simplest type of magnet. It has two poles, one north and one south. Its magnetic field lines form simple closed loops which emerge from the north pole, re-enter at the south pole, then pass through the body of the magnet. The simplest example of a dipole magnet is a ''bar magnet''. Bar Magnet" hyperphysics; http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/elemag.html/ref> Dipole magnets in accelerators In particle accelerators, a dipole magnet is the electromagnet used to create a homogeneous magnetic field over some distance. Particle motion in that field will be circular in a plane perpendicular to the field and collinear to the direction of particle motion and free in the direction orthogonal to it. Thus, a particle injected into a dipole magnet will travel on a circular or helical trajectory. By adding several dipole sections on the same plane, the bending radial effect of the beam increases. In accelerator physics, dipole magnets are used to rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electric Dipole
The electric dipole moment is a measure of the separation of positive and negative electrical charges within a system, that is, a measure of the system's overall polarity. The SI unit for electric dipole moment is the coulomb-meter (C⋅m). The debye (D) is another unit of measurement used in atomic physics and chemistry. Theoretically, an electric dipole is defined by the first-order term of the multipole expansion; it consists of two equal and opposite charges that are infinitesimally close together, although real dipoles have separated charge.Many theorists predict elementary particles can have very tiny electric dipole moments, possibly without separated charge. Such large dipoles make no difference to everyday physics, and have not yet been observed. (See electron electric dipole moment). However, when making measurements at a distance much larger than the charge separation, the dipole gives a good approximation of the actual electric field. The dipole is represented by a vec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dipole Antenna
In radio and telecommunications a dipole antenna or doublet is the simplest and most widely used class of antenna. The dipole is any one of a class of antennas producing a radiation pattern approximating that of an elementary electric dipole with a radiating structure supporting a line current so energized that the current has only one node at each end. A dipole antenna commonly consists of two identical conductive elements such as metal wires or rods. The driving current from the transmitter is applied, or for receiving antennas the output signal to the receiver is taken, between the two halves of the antenna. Each side of the feedline to the transmitter or receiver is connected to one of the conductors. This contrasts with a monopole antenna, which consists of a single rod or conductor with one side of the feedline connected to it, and the other side connected to some type of ground. A common example of a dipole is the "rabbit ears" television antenna found on broadcast telev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subtropical Indian Ocean Dipole
The Subtropical Indian Ocean Dipole (SIOD) is featured by the oscillation of sea surface temperatures (SST) in which the southwest Indian Ocean i.e. south of Madagascar is warmer and then colder than the eastern part i.e. off Australia.Behera SK, Yamagata T. 2001Subtropical SST dipole events in the southern Indian Ocean Geophysical Research Letters 28: 327–330. It was first identified in the studies of the relationship between the SST anomaly and the south-central Africa rainfall anomaly; the existence of such a dipole was identified from both observational studies and model simulations . The phenomenon Positive phase of Subtropical Indian Ocean Dipole is characterized by warmer-than-normal sea surface temperature in the southwestern part, south of Madagascar, and colder-than-normal sea surface temperature off Australia, causing above-than-normal precipitation in many regions over south and central Africa. Stronger winds prevail along the eastern edge of the subtropical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
