Magnetostatics Electriccurrent is a flow of electric charge through a medium. ref name learn ... of one coulomb per second. Electriccurrent is measured using an ammeter . ref name learn physics ... ISBN 0675204496. ref This phrase is frequently used when discussing the value of an electriccurrent ... whom the unit of electriccurrent is named, in formulating the eponymous Amp re s force law which ... ions, for example may constitute an electriccurrent. To provide a definition of current that is independent ... others, the current is entirely due to proton conductor positive charge flow . For example, the electric ... and negative ions. In ice and in certain solid electrolytes, the electriccurrent is entirely composed ... in coulomb s and seconds respectively, I is in amperes. More generally, electriccurrent can be represented ... electric charges. The slow migration of these ions means that the current is visible. Gases and plasmas ... of an electriccurrent. It is defined as a Vector geometric vector whose magnitude is the electric ... mathematics scalar that represents the electriccurrent. Current density current per unit ... , , math where math I math is the electriccurrent math n math is number of charged particles per unit ..., and therefore any changing electriccurrent, gives rise to an Electromagnetism electromagnetic ... law Amp re s law , an electriccurrent produces a magnetic field . Electriccurrent produces a magnetic ... the wire. Electriccurrent can be directly measured with a galvanometer , but this method involves ... direction of the conventional electriccurrent. File Battery symbol2.svg thumb right 100px ... the same electriccurrent, and has the same effect in a circuit, as an equal flow of negative charges ... to that of conventional or electriccurrent. Reference direction When analyzing electrical circuits ... borealis and aurora australis . The artificial form of electriccurrent is the flow of conduction ... equipment. In electronics , other forms of electriccurrent include the flow of electrons through ... more details
Korail Line 1, Line 4, Bundang br and Yongsan Deokso Line br See List of current systems for electric ... List of current systems for electric rail traction 25 kV AC 60 Hz overhead 60 Hz overhead ..., JR Kyushu 25 kV AC 50 Hz 50 Hz in eastern Japan, see List of current systems for electric rail ... bars, see List of current systems for electric rail traction DC, four rail DC, four rail below ... bars, see List of current systems for electric rail traction DC, four rail DC, four rail below Side ... on guide bars, see List of current systems for electric rail traction DC, four rail DC, four rail below ... on guide bars, see List of current systems for electric rail traction DC, four rail DC, four rail below ... on guide bars, see List of current systems for electric rail traction DC, four rail DC, four rail below ... on guide bars, see List of current systems for electric rail traction DC, four rail DC, four rail ... Railway electrification DEFAULTSORT List Of Current Systems For Electric Rail Traction Category ... to run three phase AC induction motors. Key to the tables below Volts voltage or volt Current DC direct current xx Hz frequency in hertz alternating current AC AC supplies are single phase electric power single phase , except where marked three phase electric power three phase Conductors overhead ... rowspan 7 flagicon Japan Japan Most tram lines Choshi Electric Railway Line Ch shi Electric Railway Ch shi, Chiba Eizan Electric Railway Kyoto, Kyoto Enoshima Electric Railway ... ref RTA Rapid Transit Cleveland, Ohio All three lines. San Diego Electric Railway & San Diego Trolley San Diego The San Diego Electric Railway is defunct, and is succeeded by the San Diego Trolley ... Subway Gwangju flagicon Slovakia Slovakia Tatra Electric Railway rowspan 4 flagicon ... and Wear Sunderland , Gateshead and Tyneside Manchester Sheffield Wath electric railway Manchester ... Industrial line. Operated 1915 1935. rowspan 3 flagicon USA United States Metra Metra Electric Metra ... more details
Wiktionarypar currentCurrent may refer to Ongoing events Current affairs disambiguation The present Science and mathematics ElectriccurrentCurrent fluid , including Ocean current s Air current s Current stream currents in rivers and streams Current density , mathematical concept unifying electriccurrent, fluid current, and others The conserved current or Noether current in physics and mathematics Current mathematics , geometrical current in differential topology Business IBM Current , an early personal information management program Ships USS Current ARS 22 Media Current TV , a cable television network owned by Al Gore Current Project for Student Journalism , non profit organization dedicated to uniting and empowering students in the United States Current newspaper Current newspaper , American trade journal Current Publishing , American publishing company Currents periodical Currents periodical , an international trade law journal Currents TV series Currents TV series , Catholic news magazine television show in U.S. KCMP , a radio station known as The Current The Current song The Current song , a song by the Blue Man Group Current album Current album by Heatwave Current film Current film , a 2009 film People Jeff Current , lead singer for Against All Will See also Currant disambiguation disambig ar cs Proud de Courant el es Corriente fr Courant gl Corrente he pl Current ru simple Current sk Pr d tr Ak m ... more details
The Current can refer to the following The Current Columbia University journal The Current journal , Columbia University s student journal of politics, culture and Jewish affairs. The Current newspaper The Current newspaper , the student newspaper of the University of Missouri St. Louis The Current NSU The Current newspaper , the student newspaper of the Nova Southeastern University The Current radio program , a current affairs radio program on CBC Radio One The Current song The Current song , a song by the Blue Man Group featuring Gavin Rossdale KCMP , a Minnesota Public Radio station known as The Current disambig ... more details
The Electric may refer to The Electric Blues Company , A backing band for former The Animals Animals keyboardist Alan Price Electric Slide , a four wall line dance Electric Cinema, Birmingham , the oldest running cinema in the UK disambig ... more details
The faradaic current is the Electriccurrentcurrent generated by the redox reduction or oxidation of some chemical substance at an electrode . The net faradaic current is the algebraic sum of all the faradaic currents flowing through an indicator electrode or working electrode . ref GoldBookRef file F02321 title faradaic current ref References references chem stub Category Electrochemistry ... more details
Dark current is the constant response exhibited by a receptor of radiation during periods when it is not actively being exposed to light. It may refer to Dark current biochemistry The depolarizing Electriccurrentcurrent , carried by Sodium Na sup sup ions , that flows into a photoreceptor cell when unstimulated. Dark current physics The relatively small electriccurrent that flows through a photosensitive device when no photons are entering the device. Dark current chemistry The constant response produced by a spectroscopy spectrochemical receptor, in the absence of radiation. disambig Category Analytical chemistry Category Electrical engineering Category Electronic engineering Category Photoreceptor cells Category Optoelectronics de Dunkelstrom es Corriente de oscuridad ... more details
Constant current is a term most often used in electronics to describe a system that can vary the voltage across an electronic circuit to maintain a constant electriccurrent . When a component is indicated to be driven by a constant current, the driving circuit in essence is a current regulator and must appear to the component as a current source of suitable reliability. An important usage of constant current power supplies are LED s. While a high resistance series resistance is sufficient to light an LED sometimes the design needs to guard against high current. Another use is in fluorescent lamp s which have very dynamic electrical resistance and are optimally operated within a short range of currents. ref Caladen Circuit Corner, before Sep 5 2009, http caladan.nanosoft.ca c4 ccorner 4.php LED Current Controller ref See also Current source LED circuit References reflist Category Electriccurrent Category Electrical power control Category Electronics terms electronics stub ... more details
The limiting current , in electrochemistry, is the limiting value of a faradaic current that is approached as the rate of charge transfer to an electrode is increased . The limiting current can be approached, for example, by increasing the electric potential or decreasing the rate of mass transfer to the electrode. It is independent of the applied potential over a finite range, and is usually evaluated by subtracting the appropriate residual current from the measured total current. ref http www.iupac.org goldbook L03532.pdf ref A limiting current can have the character of an adsorption , catalytic , diffusion , or kinetic current, and may include a migration current. See also Butler Volmer equation References references chem stub Category Electrochemistry ru it Corrente limite ... more details
In condensed matter physics and electrochemistry , drift current is the electriccurrent , or movement of charge carrier s, which is due to the applied electric field , often stated as the electromotive force over a given distance.When an electric field is applied across a semiconductor material,the current ... carriers can be thermally generated, drift current is temperature dependent. When an electric field ... with the electric field, whereas the negatively charged electrons move against the electric field. It is distinguished from diffusion current manifested via thermal or density gradients , which results from the random Brownian motion of charge carriers independent of electrical stimulus. If an electric ... of electrons in a straight line is known as drift current. Drift current also depends on the mobility of charge carriers in the respective conducting medium. Drift current in a p n junction diode In a p ... region, respectively. Due to the diffusion of the majority charge carriers across the junction, an electric ... are generated thermally near the junction, they drift slowly along the junction plane, aided by the electric field of the barrier potential. This current, which arises because of the motion of the drift of minority charge carriers, is the drift current in a p n junction diode. It flows in a direction opposite to the diffusion current which arises owing to the motion of the majority charge carriers across the junction. At equilibrium in an unbiased p n junction diode, the diffusion current, which flows from the p to n region, is exactly balanced by the equal and opposite drift current. ref ..., 9788126510894 pages 1115 ref In a biased p n junction, the drift current is independent of the biasing ... electric field intensity. Holes move towards the negative terminal and electrons move towards the positive ... a current known as drift current . Drift current due to the charge carriers such as free electrons and holes is the current passing through a square centimeter area perpendicular to the direction of flow ... more details
Energy current is a flow of energy defined by the Poynting vector E H , as opposed to normal electriccurrentcurrent flow of charge physics charge . It was originally postulated by Oliver Heaviside . Explanation Energy current is a somewhat informal term that is used, on occasion, to describe the process of energy transfer in situations where the transfer can usefully be viewed in terms of a flow. It is particularly used when the transfer of energy is more significant to the discussion than the process by which the energy is transferred. For instance, the flow of fuel oil in a pipeline could be considered as an energy current, although this would not be a convenient way of visualising the fullness of the storage tanks. The units of energy current are those of power watt W . This is closely related to energy flux density, which is the rate of energy transfer per unit area measured in W m . Energy current in electromagnetism A specific use of the concept of energy current was promulgated by Oliver Heaviside in the last quarter of the 19th century. Building on the concept of the Poynting vector , which describes the flow of energy in a transverse electromagnetic wave as the vector product of its electric and magnetic fields E H , Heaviside sought to extend this by treating the transfer of energy due to the electriccurrent in a conductor in a similar manner. In doing so he reversed the normal view of current, so that the electric and magnetic fields due to the current are the prime ... current view presented a number of difficulties, most notably that in asserting that the energy flowed in the electric and magnetic fields around the conductor the theory is unable to explain ... electrons, the Drude model effectively deals with the traditional charge current and the Heaviside energy current views simultaneously. With this achievement of unification , the energy current approach ... charge current approach, which defines the concepts of current, voltage, resistance, etc, as commonly ... more details
electric charge above. DEFAULTSORT Conserved Current Category Electromagnetism Category Theoretical ...Unreferenced date December 2009 In physics a conserved current is a current, math j mu math , that satisfies the continuity equation math partial mu j mu 0 math . The continuity equation represents a conservation law, hence the name. Indeed, integrating the continuity equation over a volume math V math , large enough to have no net currents through its surface, leads to the conservation law math partial over partial t Q 0 , math where math Q int V j 0dV math is the conserved quantity. In gauge theory gauge theories the gauge fields couple to conserved currents. For example, the electromagnetic field couples to the charge conservation conserved electriccurrent . Conserved quantities and symmetries Conserved current is the flow of the canonical conjugate of a quantity possessing a continuous function continuous translational symmetry . The continuity equation for the conserved current is a statement of a conservation law . Examples of canonical conjugate quantities are Time and energy the continuous ... Wave function Phase waves phase and electric charge the continuous phase angle symmetry of the wave function implies the Electric charge Conservation of charge conservation of electric charge Conserved ... the existence of a conserved current to the existence of a symmetry of some quantity in the system under study. In practical terms, all conserved currents are Noether current s, as the existence of a conserved current implies the existence of a symmetry. Conserved currents play an important role in the theory of partial differential equation s, as the existence of a conserved current points to the existence ... charge forms the zeroth component of the four current 4 current . Conserved currents in electromagnetism ... partial rho partial t nabla cdot mathbf J 0 math where is the free electric charge density in units of C m J is the current density J math rho math v v is the velocity of the charges. The equation would ... more details
Refimprove date June 2009 File Types of current.svg thumb 250px Direct Current red curve . The horizontal axis measures time the vertical, current or voltage. Direct current DC is the unidirectional flow of electric charge . Direct current is produced by sources such as battery electrical batteries , thermocouple s, solar cell s, and commutator type electric machines of the dynamo type. Direct current ... beams . The electric charge flows in a constant direction, distinguishing it from alternating current AC . A archaism term formerly used for direct current was galvanic current . ref cite book title ... current source . The DC solution of an electric circuit is the solution where all voltages and currents ... no variations in voltage , but may still have variations in output electric power power and current ... Electriccurrent Category Electric power Category American inventions am ar bn ... page 10 url http books.google.com books?id C2 9bcIjPBsC&pg PA10&dq 22galvanic current 22 22direct current 22 v onepage&q 22galvanic 20current 22 20 22direct 20current 22&f false ref File Current rectification diagram.svg right 250px thumb Types of direct current. Direct current may be obtained from an alternating current supply by use of a current switching arrangement called a rectifier , which ... current to flow only in one direction. Direct current may be made into alternating current with an inverter electrical inverter or a motor generator set. The first commercial electric power transmission developed by Thomas Edison in the late nineteenth century used direct current. Because of the significant advantages of alternating current over direct current in transforming and transmission, electric power distribution is nearly all alternating current today. In the mid 1950s, HVDC transmission was developed, and is now an option instead of long distance high voltage alternating current systems. For applications requiring direct current, such as third rail power systems, alternating current ... more details
. The current collector arms are electrical conductivity electrically conductive but mounted Electrical ... with the switch , transformer or Electric motor motor . The Rail profile steel rails of the Track rail transport tracks act as the Ground electricity electrical return . Electric vehicles that collect their current from overhead line system use different forms of one or two arm pantograph rail pantograph collectors , bow collector s, or trolley pole s. The current collection device presses ... . Contact shoe Electric railways with third rail s in tunnel s carry collector shoes projecting laterally ... and stud contact system s. A pair of contact shoes was used on Conduit current collection underground current collection systems . See also Ski collector References unreferenced date July 2008 commons Category Current collector Category Rail technologies ru uk ... more details
Unreferenced auto yes date December 2009 Image Planck current.png frame right 1 conductors, F sub p sub Planck force, l sub p sub Planck length, I sub p sub Planck current. The Planck current is the unit of electric current , denoted by I sub p sub , in the system of natural units known as Planck units . math I p q p t p c 6 4 pi varepsilon 0 G frac 1 2 math 3.479 × 10 sup 25 sup ampere A where math q p c hbar 4 pi varepsilon 0 frac 1 2 math is the Planck charge math t p hbar G c 5 frac 1 2 math is the Planck time math varepsilon 0 math permittivity in vacuum math hbar math is the reduced Planck constant G is the gravitational constant c is the speed of light in vacuum. The Planck current is that current which, in a conductor material conductor , carries a Planck charge in Planck time. Alternatively, the Planck current is that constant current which, if maintained in two straight parallel conductors of infinity infinite length and negligible circular cross section, and placed a Planck length apart in vacuum , would produce between these conductors a force equal to a Planck force per Planck length. Planckunits DEFAULTSORT Planck Current Category Natural units Current, planck Category Units of electric current Physics stub ar ca Corrent de Planck es Intensidad el ctrica de Planck eo Elektra kurento de Planck ko it Corrente di Planck pl Nat enie Plancka pt Corrente el trica de Planck ru sl Planckov tok fi Planckin s hk virta ... more details
current is a quantity that is defined in terms of the rate of change of electric displacement field . Displacement current has the units of electriccurrent density , and it has an associated magnetic field just as actual currents do. However it is not an electriccurrent of moving Electric charge charges , but a time varying electric field . In materials, there is also a contribution from the slight ... November 2011 in connection with the displacement of electric particles in a dielectric medium. Maxwell added displacement current to the electriccurrent term in Amp re s circuital law Amp re s Circuital ... current may also be expressed in terms of electric flux math I mathrm D varepsilon frac partial ... plate, charging the capacitor and increasing the electric field between its plates. The same current ... electric field distribution inside the capacitor, the displacement current density J sub D sub is found ... current Capacitance br DEFAULTSORT Displacement Current Category Electriccurrent Category ... electricity, magnetism and optics into one single unified theory. The displacement current term ... many phenomena, most particularly the existence of electromagnetic wave s. Explanation The electric ... sub 0 sub is the permittivity of free space E is the electric field intensity P is the polarization ... the displacement current density , which therefore has two components in a dielectric ref name ... movement of charge, but it does have an associated magnetic field, just as does a current due to charge motion. Some authors apply the name displacement current to only this contribution. ref name Griffiths ... PPA204,M1 ref The second term on the right hand side is associated with the electric polarization polarization ... in molecules move a little under the influence of an applied electric field . The positive and negative ... state of polarization corresponds to charge movement and so is equivalent to a current. This polarization is the displacement current as it was originally conceived by Maxwell. Maxwell made no special ... more details
flares ref Low, B. C. and Wolfson, R. 1988 Spontaneous formation of electriccurrent sheets and the origin ...Image Heliospheric current sheet.gif thumb 300px The heliospheric current sheet results from the influence ... ref http wso.stanford.edu gifs HCS.html Artist s Conception of the Heliospheric Current Sheet Wilcox Solar Observatory, Stanford University ref A current sheet is an electriccurrent that is confined to a surface, rather than being spread through a volume of space. Current sheets feature in magnetohydrodynamics MHD , the study of the behavior of electrically conductive fluids if there is an electriccurrent through part of the volume of such a fluid, magnetic forces tend to expel it from the fluid, compressing the current into thin layers that pass through the volume. The largest occurring current sheet in the Solar System is the so called Heliospheric current sheet , which is about 10,000 ... physics plasmas such as the sun solar corona , current sheets may have an aspect ratio breadth divided ... 1. Because current sheets are so thin in comparison to their size, they are often treated as if they have ... MHD . In reality, no current sheet may be infinitely thin because that would require infinitely fast motion of the charge carriers whose motion causes the current. Current sheets in plasmas store energy ... arise near strong current sheets, which are prone to collapse, causing magnetic reconnection and rapidly releasing the stored energy. ref Biskamp, Dieter May 1986 Magnetic reconnection via current sheets ... of magnetic confinement fusion , which requires strong electric currents in a hot plasma. Magnetic field of an infinite current sheet An infinite current sheet can be modelled as an infinite number of parallel wires all carrying the same current. Assuming each wire carries current I , and there are N ... R is a rectangular loop surrounding the current sheet. In the two sides perpendicular to the sheet, math ... math Solving for B , plugging in for I sub enc sub total current enclosed in path R as I N L , and simplifying ... more details
Expert subject Physics date May 2009 Unreferenced date May 2009 Diffusion current is a electriccurrentcurrent in a semiconductor caused by the diffusion of charge carriers holes and or electrons . Diffusion current can be in the same or opposite direction of a drift current , that is formed due to the electric field in the semiconductor. At equilibrium in a p n junction , the forward diffusion current in the depletion region is balanced with a reverse drift current, so that the net current is zero ... . Introduction Diffusion current versus drift current class wikitable Diffusion current Drift current Diffusion current occurs even though there isn t an electric field applied to the semiconductor. Drift current depends on the electric field applied on the p n junction diode. It depends on constants ... . It depends upon permittivity. Direction of the diffusion current depends on the change in the carrier concentrations, not the concentrations themselves. Direction of the drift current depends on the polarity of the applied field. Carrier actions No external electric field across the semiconductor is required for the diffusion of current to take place. This is because diffusion takes place due ... to a place of lower concentration. Hence, due to the flow of holes and electrons there is a current. This current is called the diffusion current. The drift current and the diffusion current make up the total current in the conductor. The change in the concentration of the carrier particles develops a gradient. Due to this gradient, an electric field is produced in the semiconductor. Derivation To derive the diffusion current in a semi conductor diode, the depletion layer must be large enough compared to the mean free path. One begins with the net current equation in a semi conductor ... obtains the equation of current caused due to diffusion big J sub n sub q sup 2 sup D sub n sub N ... observe that the current depends exponentially on the input voltage V sub a sub , also the barrier ... more details
currentelectric motor s and transformer s may draw several times their normal full load current ...Image Inrush current.gif frame right An example of inrush current transients during capacitor bank energization. The peak inrush current transient rises as high as 28.4 kA Inrush current , input surge current or switch on surge refers to the maximum, instantaneous input current electricity current drawn ... inrush currents much higher than their steady state currents, due to the charging current of the input ... when the usually harmless inrush current flows. Transformers When a transformer is first energized a transient current up to 10 to 50 times larger than the rated transformer current can flow ... voltage. For large transformers, inrush current can last for several seconds. Toroid transformers ... are limiting the current. File Rktr Inrush 100Va.png thumb right An example of inrush current transients during a 100VA toroid transformer energization. Inrush peak raises to 50 times of nominal current ... to limit the current charging input capacitors. However, this approach is not very efficient, especially .... Inrush current can also be reduced by inrush current limiter s. Negative temperature coefficient NTC ... damage caused by inrush current. A thermistor is a thermally sensitive resistor with a resistance ... NTC thermistors at Temperatures.com ref . As the inrush current limiter self heats, the current begins to flow through it and warm it. Its resistance begins to drop and a relatively small current ... heated inrush current limiter offers little resistance in the circuit, with a low voltage drop with respect ... current unless it cools for more than 1 minute to get a higher resistance. Another disadvantage is that the NTC thermistor is not short circuit proof. Another way to avoid the transformer inrush current .... The circuit would support a current limited precharge mode during the charging of capacitors, and then switch ... charge. References reflist http www.ametherm.com Inrush Current inrush current faq.html Inrush Current ... more details
about current sources on ESP DEFAULTSORT Current Source Category Analog circuits Category Electric ...Image Ohms law current source.svg thumb 150px Figure 1 An ideal current source, I , driving a resistor, R , and creating a voltage V A current source is an electrical or electronic device that delivers or absorbs electriccurrent. A current source is the Duality electrical circuits dual of a voltage source . The term constant current sink is sometimes used for sources fed from a negative voltage supply. Figure 1 shows a schematic for an ideal current source driving a resistor load. Background float ... 2em 0 Image Current Source.svg align center Voltage source Current Source align center style padding 1em 2em 0 Image Voltage Source Controlled .svg style padding 1em 2em 0 Image Current Source Controlled .svg align center Controlled Voltage Source Controlled Current Source align center style padding ... current source is a circuit element where the current through it is independent of the voltage across it. It is a mathematical model , which real devices can only approach in performance. If the current through an ideal current source can be specified independently of any other variable in a circuit, it is called an independent current source. Conversely, if the current through an ideal current source is determined by some other voltage or current in a circuit, it is called a dependent or controlled current source . Symbols for these sources are shown in Figure 2. An independent current source with zero current is identical to an ideal open circuit . For this reason, the internal resistance of an ideal current source is infinite. The voltage across an ideal current source is completely ... voltage and thus zero Electric power power delivered. When connected to a load resistance , the voltage ... . Thus, an ideal current source, if such a thing existed in reality, could supply unlimited power and so would represent an unlimited source of energy. No real current source is ideal no unlimited energy ... more details
dablink This page is about the electriccurrent density in electromagnetism . For the probability current density in quantum mechanics, see Probability current . Current density is a measure of the density of flow of a conserved charge physics charge . Usually the charge is the electric charge, in which case the associated current density is the electriccurrent per unit area of cross section, but the term current density can also be applied to other conserved quantities. It is defined as a vector geometric vector whose magnitude is the current per cross sectional area. In SI unit s, the electriccurrent density is measured in ampere s per square metre . Definition Electriccurrent is a coarse, average quantity that tells what is happening in an entire wire. The distribution of flow of electric charge charge is described by the current density math mathbf J mathbf r , t qn mathbf r ,t mathbf v d mathbf r ,t rho mathbf r ,t mathbf v d mathbf r ,t , , math where J r ,&thinsp t is the current ... the current simply is proportional to the electric field, as expressed by math mathbf J sigma mathbf ... average drift velocity at position r at time t SI unit metre s per second Importance Current density ... strongly upon the designed current level, and the current density then is determined by the dimensions ... the lower current demanded by smaller semiconductor devices devices , there is trend toward higher current densities to achieve higher device numbers in ever smaller semiconductor chip chip areas. See Moore s law . At high frequencies, current density can increase because the conducting region in a wire becomes confined near its surface, the so called skin effect . High current densities have undesirable ... , making them dissipate Power physics power in the form of heat. The current density must be kept ... insulating material failing, or the desired electrical properties changing. At high current densities ... superconductors excessive current density may generate a strong enough magnetic ... more details
Unreferenced stub auto yes date December 2009 The Charged current interaction is one of the ways in which subatomic particles can interact by means of the weak force . It is mediated by the W and Z bosons SubatomicParticle W boson and SubatomicParticle W boson bosons . The interaction is often incorrectly believed to be called charged because the W bosons have electric charge . However, the charged current that gives the interaction its name is that of the interacting particles. For example, the charged current contribution to the SubatomicParticle Electron neutrino SubatomicParticle Electron SubatomicParticle Electron neutrino SubatomicParticle Electron elastic scattering amplitude math mathfrak M mathrm CC propto J mu mathrm CC mathrm e to nu mathrm e J mathrm CC mu nu mathrm e to mathrm e math where the charged currents describing the flow of one fermion into the other are given by math J mathrm CC mu f to f bar u f gamma mu frac 1 2 left 1 gamma 5 right u f . math See also Neutral current DEFAULTSORT Charged Current Category Electroweak theory Particle stub ar ru uk ... more details
About an atmospheric effect the effect in nuclear magnetic resonance Chemical shift Factors causing chemical shifts A ring current is an electric current carried by charged particles trapped in a planet s magnetosphere . It is caused by the longitudinal drift of energetic 10&ndash 200 k electron volt eV particles. Earth s ring current File Currents.jpg thumb right 300px Schematic view of the different current systems which shape the Earth s magnetosphere . Earth s ring current is responsible for shielding the lower latitudes of the Earth from magnetospheric electric fields. It therefore has a large effect on the electrodynamics of geomagnetic storm s. The ring current system consists of a band, at a distance of 3 to 5 Earth radius R sub E sub , ref cite book title Introduction to Geomagnetically Trapped Radiation author Martin Walt year 1994 ref which lies in the celestial sphere equatorial plane and circulates clockwise around the Earth when viewed from the north . The particles of this region produce a magnetic field in opposition to the Earth s magnetic field and so an Earthly observer would observe a decrease in the magnetic field in this area. The ring current energy is mainly carried around by the ions, most of which are protons. However, one also sees alpha particles in the ring current, a type of ion that is plentiful in the solar wind. In addition, a certain percentage are O sup sup oxygen ions, similar to those in the ionosphere of Earth, though much more energetic. This mixture of ions suggests that ring current particles probably come from more than one source. The ring current and geomagnetic storms During a geomagnetic storm , the number of particles in the ring current will increase. As a result there is a decrease in the effects of Earth s magnetic field geomagnetic field . See also Van Allen radiation belt Magnetosphere References references cite journal doi 10.1023 B SPAC.0000007516.10433.ad title Ring Current Energy Input and Decay journal Space S ... more details
A streaming current and streaming potential are two interrelated electrokinetic phenomena studied in the areas of surface chemistry and electrochemistry . They are an electriccurrent or Electric potential potential which originates when an electrolyte is driven by a pressure gradient through a channel or porous plug with charged walls. ref name Lyklema cite book author Lyklema, J. title Fundamentals of Interface and Colloid Science year 1995 publisher Academic Press ref ref name Li cite book author Li, D. title Electrokinetics in Microfluidics year 2004 publisher Academic Press ref ref name Chang cite book author Chang, H.C., Yeo, L. title Electrokinetically Driven Microfluidics and Nanofluidics year 2009 publisher Cambridge University Press ref The first observation of the streaming potential is generally attributed to the German physicist Georg Hermann Quincke in 1859. Applications Streaming .... When both electrodes are held at the same potential, the streaming current is measured directly as the electriccurrent flowing through the electrodes. Alternatively, the electrodes can be left floating ... Interface Sci. 208, 329 1998 References references Category Electriccurrent Category Colloidal ... be used to generate electric power electrical power , however this process has not been applied so ... of the streaming current Adjacent to the channel walls, the charge neutrality of the liquid is violated ... along with the pressure driven fluid flow gives rise to a net charge transport the streaming current ... potential is defined as positive when the electric potential is higher on the high pressure end of the flow system that on the low pressure end. The value of streaming current observed in a capillary ... conduction conduction current, which is equal in magnitude to the streaming current at steady ... Symbols I sub str sub streaming current under short circuit conditions, A U sub str sub streaming potential at zero net current conditions, V I sub c sub conduction current, A sub rs sub relative permittivity ... more details
In electrochemistry , partial current is defined as the electriccurrent associated with anode anodic or cathode cathodic half of the electrode chemical reaction reaction . Depending on the electrode half reaction, one can distinguish two types of partial current cathodic partial current I sub c sub called also cathodic current is the flow of electrons from the electrode surface to a species in solution anodic partial current I sub a sub called also anodic current is the flow of electrons into the electrode from a species in solution. The cathodic and anodic partial currents are defined by IUPAC ref name iupac http goldbook.iupac.org P04407.html ref . The partial Current density current densities i sub c sub and i sub a sub are the ratios of partial currents respect to the electrode areas A sub c sub and A sub a sub i sub c sub I sub c sub A sub c sub i sub a sub I sub a sub A sub a sub The sum of the cathodic partial current density i sub c sub positive and the anodic partial current density i sub a sub negative gives the net current density i ref name cwru http electrochem.cwru.edu ed dict.htm Electrochemistry Dictionary and Encyclopedia ref i i sub c sub i sub a sub In the case of the cathodic partial current density are equal to the anodic partial current density for example, in a corrosion process ref B. Elsener, http www.surface.mat.ethz.ch education courses surfaces and interfaces chapter11 Corrosion and durability of metals , p. 252. ref , the net current density on the electrode is zero ref name cwru i sub eq sub i sub c,eq sub i sub a,eq sub 0 When more than one reaction occur on an electrode simultaneously, then the total electrode current can be expressed as ref name iupac math I Sigma I a,i Sigma I c,i math where the index i refers to the particular reactions. Notes references References Bard, A.J. and Faulkner L.R. Electrochemical Methods Fundamentals and Applications 2nd ed. , 2001 John Wiley & Sons Inc. See also Exchange current density Category Electrochemistry ... more details
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