Dablink For other words or senses of this term, see potential disambiguation . In linguistics, the Irrealis mood Potentialpotential mood The mathematic al study of potentials is known as potential theory it is the study of harmonic function s on manifold s. This mathematical formulation arises from the fact that, in physics, the scalar potential is irrotational , and thus has a vanishing Laplacian the very definition of a harmonic function. In physics , a potential may refer to the scalar potential or to the vector potential . In either case, it is a field physics field defined in space, from which many important physical properties may be derived. Leading examples are the gravitational potential and the electric potential , from which the motion of gravitating or electrically charged bodies may be obtained. Specific forces have associated potentials, including the Coulomb potential , the van der Waals potential , the Lennard Jones potential and the Yukawa potential . In electrochemistry there are Galvani potential and Volta potential . In Thermodynamics potential refers to thermodynamic potential . See also Potential difference Potential energy Category Potential es Potencial de Potential fr Potentiel d un champ vectoriel ja pl Potencja ru sl Potencial sv Potential lt Potencialas ... more details
Wiktionary potentialPotential may mean In mathematics and physics a Potential Scalar potential Vector potential A potential function , that is, a harmonic function studied in potential theory In physics and engineering Potential energy Magnetic potential Electric potential Electromagnetic four potential Coulomb potential van der Waals potential Lennard Jones potential Yukawa potential In linguistics Irrealis mood PotentialPotential mood In biology Action potential Membrane potential Water potential In Television Potential Buffy episode Potential Buffy episode , an episode of Buffy the Vampire Slayer Potential and new Slayers , characters in Buffy the Vampire Slayer Disambig cs Potenci l de Potential Begriffskl rung fr Potentiel it Potenziale he lt Potencialas ja ru simple Potential sv Potential ... more details
Orphan date October 2006 In conservation biology , invader potential is the qualitative and quantitative measure of a given invasive species probability to invade a given ecosystem . Exotic species with high invader potential are ones with high tolerance of different climates, Hypoxia environmental dissolved oxygen content for aquatic organisms , high propagule pressure and species with a large number of individuals introduced. The last factor is called a transport vector, for instance, sea lamprey s and zebra mussel s were transported into the Great Lakes through the vector of ballast water in ships. Transport vector is one of the most important factors, because if a large enough number of individuals are transported to an area that they cannot thrive in, a mutation within that population to thrive in the new ecosystem is more likely. Most invaders are adapted to disturbed areas, so ecosystems that have been disrupted or roadside ditches are susceptible to invasion. Climate matching is one of the most common measures of invader potential. Mostly exotic species that have already exhibited invasive traits are studied. Biotic resistance is a controversial concept in invader potential. Small scale studies have borne the concept of diversity resistance, that diverse ecosystems resist invasions better than less diverse ecosystems. However, evidence on regional scales finds a positive correlation between diversity and number of invasions. The exact interpretation of these studies is unclear. References Ecological Predictions and Risk Assessment for Alien Fishes in North America, Cynthia S. Kolar, dagger David M. Lodge, Science 8 November 2002 Vol. 298. no. 5596, pp. 1233 1236 Category Conservation ... more details
Potential evaporation or potential evapotranspiration PET is defined as the amount of evaporation that would occur if a sufficient water source were available. If the evapotranspiration actual evapotranspiration is considered the net result of atmospheric demand for moisture from a surface and the ability of the surface to supply moisture, then PET is a measure of the demand side. Surface and air temperatures, insolation, and wind all affect this. A dryland is a place where annual potential evaporation exceeds annual precipitation. Estimates of potential evaporation mm C. W. Thornthwaite Thornthwaite equation 1948 math PET 1.6 left frac L 12 right left frac N 30 right left frac 10 , T a I right alpha math Where math PET math is the estimated potential evapotranspiration cm month math T a math is the average daily temperature degrees Celsius if this is negative, use math 0 math of the month being calculated math N math is the number of days in the month being calculated math L math is the average day length hours of the month being calculated math alpha 6.75 times 10 7 I 3 7.71 times 10 5 I 2 1.792 times 10 2 I 0.49239 math math I sum i 1 12 left frac T ai 5 right 1.514 math is a heat index which depends on the 12 monthly mean temperatures math T ai math . ref name thornthwaite48 Cite journal doi 10.2307 210739 last Thornthwaite first C. W. title An approach toward a rational classification of climate journal Geographical Review volume 38 issue 1 pages 55 94 year 1948 url http www.unc.edu courses 2007fall geog 801 001 www ET Thornthwaite48 GeogrRev.pdf postscript Bot inserted parameter. Either remove it or change its value to . for the cite to end in a . , as necessary. inconsistent citations ref Somewhat modified forms of this equation appear in later publications 1955 and 1957 ... last Bonan first Gordon title Ecological Climatology publisher CUP year 2002 location Cambridge, U.K. ... of potential evaporation. Category climate Category weather climate stub ... more details
In mechanics , a pair potential is a function that describes the potential energy of two interacting objects. Examples of pair potentials include the Coulomb s law , Newton s law of universal gravitation , the Lennard Jones potential and the Morse potential . Pair potentials are very common in physics exceptions are very rare. An example of a potential energy function that is not a pair potential is the three body Axilrod Teller potential . Category Mechanics physics stub ... more details
Contact potential may refer to Contact electrification Galvani potential difference in electrochemistry, at a junction of two metals Volta potential difference in electrochemistry, between two points in vacuum near surfaces of two metals in contact Disambig ... more details
The term potential function may refer to A mathematical function mathematics function whose values are a physical potential . The class of functions known as harmonic function s, which are the topic of study in potential theory . The potential function of a potential game . A function used in the potential method of amortized analysis to describe an investment of resources by past operations that can be used by future operations. mathdab ... more details
A potential gradient is the local space derivative rate of change of the potential with respect to displacement. In electrostatics then, it is the local space rate of change of the electric potential math mathbf E delta V delta s math http niuhep.physics.niu.edu willis phys251 chapter 19 day 2.html Units are volt s per meter V m . The electric field is the same as the potential gradient but with opposite sign. In biology , potential gradient is the net difference in electric charge across a cell membrane . Category Electronics terms electronics stub pl Gradient potencja u ... more details
Volta potential also called Volta potential difference , or contact potential difference , or outer potential difference , , delta psi in electrochemistry , is the electric potential difference between two points 1 and 2 in the vacuum point 1 close to the surface of metal M sub 1 sub point 2 close to the surface of metal M sub 2 sub or electrolyte where M sub 1 sub and M sub 2 sub are two uncharged metals brought into contact. ref http www.iupac.org goldbook C01293.pdf IUPAC Gold Book, definition of contact Volta potential difference. ref The Volta potential is named after Alessandro Volta . Volta potential between two metals When two metals are electrically isolated from each other, an arbitrary potential difference may exist between them. However, when two different metals are brought into contact, electrons will flow from the metal with a lower work function to the metal with the higher work function until the electrochemical potential of the electrons in the bulk of both phases are equal. The actual numbers of electrons that passes between the two phases is small, and the occupancy of the Fermi level s is practically unaffected. Measurement of Volta potential The Volta potential difference is measurable. It is related to the capacitance of an electrostatic capacitor , the two sides of which are made of the two metals for which the Volta potential difference is measured and the electrical charge used to load the capacitor. The Volta potential difference between a metal and an electrolyte can be measured in a similar fashion. ref V.S. Bagotsky, Fundamentals of Electrochemistry , Willey Interscience, 2006. ref See also Electrode potential Absolute electrode potential Electrical potential Galvani potentialPotential difference voltage Volt References reflist physics stub Category Electrochemistry Category Potential ca Potencial Volta de Volta Spannung es Potencial Volta it Potenziale Volta pl Potencja Volty uk ... more details
Definition The potential of something to grow. Overview In the case of a company, it is its potential to grow larger in terms of market capitalization , Production, costs, and pricing production , sales , revenue , employment , or management . In the case of living creatures, they initially have more growth potential than later on. Category Business terms business stub ... more details
Cleanup date February 2008 Unreferenced date February 2008 Biotic potential is the maximum reproductive capacity of a population if resources are unlimited. Full expression of the biotic potential of an organism is restricted by environmental resistance , any condition that inhibits the increase in number of the population. It is generally only reached when environmental conditions are very favorable. A species reaching its biotic potential would exhibit exponential population growth and be said to have a high fertility , that is, how many offspring are produced per mother. Biotic Potential is a fundamental species characteristic, defined by Chapman 1925 as the inherent power of organisms to reproduce and survive ref Chapman, R. N., 1925. Animal Ecology with Special Reference to Insects. Burgess Brook Inc.,Minneapolis. 370 pp. See pp.158 161. ref . In 1931, Chapman redescribed it as It is a sort of algebraic sum of the number of young produced at each reproduction, number of reproductions ... to a vital index Vital Index number of births number of deaths 100 Biotic potential is the highest ... mortality rate. Significance of Biotic Potential If the potential value of population increase can ... potentialpotential increase and subtract the actual or observed value of decrease this difference ... potential. Components of Biotic Potential Reproductive potentialpotential natality It is the upper limit to biotic potential in the absence of mortality Survival potential Because reproductive potential does not account for the number of gametes surviving, survival potential is a necessary component of biotic potential it is the reciprocal of Death mortality in the absence of mortality, biotic potential reproductive potential Chapman identified two components nutritive potential the ability to acquire and utilize food for growth and energy protective potentialpotential ability of the organism ... mating care of young Graham Moss References references DEFAULTSORT Biotic Potential Category Reproduction ... more details
Electrode potential , E , in electrochemistry , according to an IUPAC definition, ref IUPAC. Compendium of Chemical Terminology , 2nd ed. the Gold Book . Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford 1997 . XML on line corrected version http goldbook.iupac.org ... 10.1351 goldbook. http goldbook.iupac.org E01956.html Entry Electrode Potential ref is the electromotive ... electrode , and on the right hand side is the electrode the potential of which is being defined ... hydrogen electrode potential of 0 by convention , one obtains E sub Cell sub E sub Right ... potential is measured in volt s V . Measurement Image Three electrode setup.png thumb right Three electrode setup for measurement of electrode potential. The measurement is generally conducted using ... electrode standard hydrogen electrode or an equivalent The measured potential of the working ... potential , or a potential with a non zero net reaction on the working electrode but zero net current corrosion potential , Mixed potential theory mixed potential , or a potential with a non zero ... , or by using an electrolyte of sufficiently high Conductivity electrolytic conductivity . The potential ... electrode and the negative terminal to the reference electrode. Potential difference of a cell ... potential See also Electrolytic cell Anode and cathode definitions depend on charge and discharge Potential of a cell assembled of two electrodes can be determined from the two individual electrode ... potential difference of a galvanic cell, ref IUPAC Gold Book. Definition of the potential difference of a galvanic cell. http goldbook.iupac.org E01934.html ref according to which the electric potential ... electrode potential Absolute electrode potential Table of standard electrode potentials Electrical potential Galvani potentialPotential difference voltage References references DEFAULTSORT Electrode Potential Category Electrochemistry ca Potencial d el ctrode de Elektrodenpotential et Elektroodipotentsiaal ... more details
In mathematics , the Bessel potential is a potential theory potential similar to the Riesz potential but with better decay properties at infinity. If s is a complex number with positive real part then the Bessel potential of order s is the operator math I Delta s 2 math where is the Laplace operator and the fractional calculus fractional power is defined using Fourier transforms. See also Riesz potential Fractional integration Sobolev space Fractional Schr dinger equation References eom id B b110420 title Bessel potential operator first R. last Duduchava Citation last1 Grafakos first1 Loukas title Modern Fourier analysis publisher Springer Verlag location Berlin, New York edition 2nd series Graduate Texts in Mathematics isbn 978 0 387 09433 5 doi 10.1007 978 0 387 09434 2 id MathSciNet id 2463316 year 2009 volume 250 eom id B b120170 title Bessel potential space first L.I. last Hedberg eom id B b015870 first E.D. last Solomentsev citation first Elias last Stein authorlink Elias Stein title Singular integrals and differentiability properties of functions publisher Princeton University Press location Princeton, NJ year 1970 isbn 0 691 08079 8 Category Fractional calculus Category Partial differential equations Category Potential theory Category Singular integrals ... more details
multiple issues confusing June 2010 unreferenced June 2010 The endocochlear potential is the main resting potential in the cochlea . It is a positive direct current of 80mV which can be recorded from the endolymph with electrodes. When a sound is presented, the endocochlear potential changes either positive or negative in the endolymph , depending on the stimulus. The change in the potential is called the summating potential . With the movement of the basilar membrane , a shear force is created and a small potential is generated due to a difference in potential between the endolymph scala media 80 mV and the perilymph vestibular and tympanic ducts 70 mV . An acoustic stimulus produces a simultaneous change in conductance at the membrane of the receptor cell. Because there is a steep gradient 150 mV, changes in membrane conductance are accompanied by rapid influx and efflux of ions which in turn produce the receptor potential. This is known as the Battery Hypothesis. The receptor potential for each hair cell causes a release of neurotransmitter at its basal pole, which elicits excitation of the afferent nerve fibres. Category Anatomy ... more details
Galvani potential also called Galvani potential difference, or inner potential difference, , delta phi in electrochemistry , is the electric potential difference between two points in the bulk of two phases. ref http www.iupac.org goldbook G02574.pdf IUPAC Gold Book, definition of Galvani potential ... and a liquid e.g., a metal electrode submerged in an electrolyte . Generally, the Galvani potential ... The Galvani potential is named after Luigi Galvani . Galvani potential between two metals First, consider the Galvani potential between two metals. When two metals are electrically isolated from each other, an arbitrary potential difference may exist between them. However, when two different metals ... to the metal with the higher work function until the electrochemical potential of the electrons in the bulk ... potential between the two different phases in contact can be written as math overline mu j 1 overline mu j 2 math where math overline mu math is the electrochemical potential j denotes the species ... denote phase 1 and phase 2, respectively. Now, the electrochemical potential of a species is defined as a sum of its chemical potential and the local electrostatic potential math overline mu j mu j z j F phi math where is the chemical potential z is the electrical charge carried by a single charge carrier unity for electrons F is the Faraday constant is the electrostatic potential From the two ... hand side is the Galvani potential difference between the phases 1 and 2 . Thus, the Galvani potential ... of the chemical potential of the charge carriers in the two phases. The Galvani potential difference ... potential The Galvani potential difference is not measurable. The measured potential difference between ... of the two metals or their combination with the solution Galvani potential because the cell needs ... cell potential can be written as ref name Trasatti Sergio Trasatti, The Absolute Electrode Potential an Explanatory Note Recommendations 1986 , International Union of Pure and Applied Chemistry ... more details
Unreferenced date December 2006 A synaptic potential also known as a postsynaptic potential is an alteration in the membrane potential of a cell resulting from activation of a chemical synapse synaptic input . All animal cells maintain a voltage difference between the intracellular and extracellular regions, holding the intracellular region at a negative voltage that in a baseline state is usually in the range 30 to 70 millivolts. Synaptic inputs from neuron s can alter this voltage difference. If the intracellular voltage rises, the signal is called an excitatory postsynaptic potential EPSP if it falls the signal is called an inhibitory postsynaptic potential IPSP . If the cell is electrically excitable, a sufficiently large EPSP may cause it to generate an action potential . Category Cell biology Neuroscience stub Medicine stub ... more details
Electromagnetism cTopic Electrostatics In classical electromagnetism , the electric potential denoted by , sub E sub or V also called the electrostatic potential at a point in space is the electric potential energy divided by electric charge charge associated with a static time invariant electric field . Typically measured in volt s, the electric potential is a scalar physics scalar quantity equivalent to a joule per coulomb . There is also a generalized electric scalar potential that is used ... potential cannot be simply interpreted as the ratio of potential energy to charge, however. Introduction ... field. Classical mechanics explores the concepts such as Force physics force , energy , potential etc. in more detail. Force and potential energy are directly related. As an object moves in the direction that the force accelerates it, its potential energy decreases. For example, the gravitational potential energy of a cannonball at the top of a hill is greater than at the base of the hill. As the object falls, that potential energy decreases and is translated to motion, or inertial kinetic energy. For certain forces, it is possible to define the potential of a field such that the potential .... The potential of an electric field is called the electric potential. The synonymous term electrostatic potential is also in common use. The electric potential and the magnetic vector potential together form a four vector , so that the two kinds of potential are mixed under Lorentz transformation s. In electrostatics The electric potential at a point r in a static electric field E is given by the line ... is an arbitrary path connecting the point with zero potential to r . When the Curl mathematics curl ... and determined by the gradient of the potential math mathbf E mathbf nabla V mathbf E . , math Then, by Gauss s law , the potential satisfies Poisson s equation math mathbf nabla cdot mathbf E mathbf ... potential is closely linked with potential energy . A test charge q has an electric potential ... more details
Image Action potential vert.png thumb 350px A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane . B. Actual recordings of action potentials are often distorted compared to the schematic view because of variations in electrophysiology electrophysiological techniques used to make the recording. The threshold potential is the membrane potential to which a membrane must be depolarization depolarized to initiate an action potential . It often can be between 40 and 55 volt mV , but it can vary based upon several factors. If ion channel s are available, that will move the potential in the direction of the equilibrium potential for that ion sodium ion channel Na sup sup is approximately 55mV potassium channel K sup sup is approximately 95mV chloride channel Cl sup sup is approximately 90mV Therefore, resting ion channel for sodium will depolarization depolarize and thus excite, while channels for potassium or chloride will hyperpolarization biology hyperpolarize and thus inhibit. External links eMedicineDictionary threshold stimulus GeorgiaPhysiology 1 1ch4 s1ch4 8 http www.cameron.edu gabrielr PHYCH4 sld013.htm Description at cameron.edu http www.ncbi.nlm.nih.gov books bv.fcgi?rid mcb.figgrp.6213 Diagram at nih.gov neuro stub Category Electrophysiology de Schwellenpotential pl Potencja progowy ... more details
Unreferenced date March 2009 A velocity potential is used in fluid dynamics , when a fluid occupies a simply connected region and is irrotational . In such a case, math nabla times mathbf u 0, math where math mathbf u math denotes the flow velocity of the fluid. As a result, math mathbf u math can be represented as the gradient of a scalar field scalar function math Phi math math mathbf u nabla Phi math , math Phi math is known as a velocity potential for math mathbf u math . A velocity potential is not unique. If math a math is a constant then math Phi a math is also a velocity potential for math mathbf u math . Conversely, if math Psi math is a velocity potential for math mathbf u math then math Psi Phi b math for some constant math b math . In other words, velocity potentials are unique up to a constant. Unlike a stream function , a velocity potential can exist in three dimensional flow. See also Hamiltonian fluid mechanics Potential flow DEFAULTSORT Velocity Potential Category Fluid dynamics Category Equations of fluid dynamics Fluiddynamics stub zh ... more details
Orphan date September 2008 Expressive potential is the degree to which a given MIDI controller music control interface input device enables a musician to control musical expression . An interface with low expressive potential enables control over a narrow range of musical expression, no matter how virtuoso virtuosic its player, whereas an interface with high expressive potential enables control over a wide range of musical expression. Expressive potential is independent of how that potential was, is, or will be realized in any given composition or performance. This independence allows the expressive potential of new musical instruments & interfaces to be compared and contrasted objectively with traditional musical instruments. The concept of expressive potential is closely related to the concept of affordance , i.e. all action possibilities latent in the environment, objectively measurable and independent of the individual s ability to recognize or realize them. One possible metric for expressive potential is the number of Degrees of freedom physics and chemistry degrees of freedom provided by the interface. The more degrees of freedom, the more independent expressive variables a musician can control independently during performance. The development of new interfaces to control musical expression is an active research area, supporting an annual conference, http nime.org New Interfaces for Musical Expression . Category Electronic music ... more details
membrane , the reversal potential also known as the Nernst potential of an ion is the membrane potential at which there is no net overall flow of that particular ion from one side of the membrane to the other. In the case of post synaptic neuron s, the reversal potential is the membrane potential ... ref In a single ion system, reversal potential is synonymous with equilibrium potential their numerical ... potential. Equilibrium refers to the fact that the net ion flux at a particular voltage is zero .... Reversal refers to the fact that a change of membrane potential on either side of the equilibrium potential reverses the overall direction of ion flux. ref name Purves The reversal potential is often called the Nernst potential , as it can be calculated from the Nernst equation . Ion channels conduct ... potential for that ion assuming the outside of the cell is at 0 volts . For example, the resting potential of most cells is close to the potassium K sup sup potassium ion reversal potential. This is because at resting potential, potassium conductance dominates. During a typical action potential ... number of sodium Na sup sup sodium ion channels, which brings the membrane potential close to the reversal potential of sodium. The relationship between the terms reversal potential and equilibrium potential only holds true for single ion systems. In multi ion systems, there are areas of the cell ... potential in the sense that membrane current reverses direction, it is not an equilibrium potential ... across the membrane. When a cell has significant permeabilities to more than one ion, the cell potential ... models The term driving force is related to equilibrium potential, and is likewise useful in understanding ... an ion s equilibrium potential and the actual membrane potential. It is defined by the following equation ... between the membrane potential and the ion s equilibrium potential i.e. V sub m sub E sub ... membrane potential, in the neuromuscular junction math EPC G ACh V m E rev , math where EPC is the end ... more details
In electrochemistry , the electrochemical potential , math bar mu math , sometimes abbreviated to ECP, is a thermodynamic measure that combines the concepts of energy stored in the form of chemical potential and electric charge electrostatics . Electrochemical potential is expressed in the unit of Joule ... , electrons , etc. has an electrochemical potential a number with units of energy at any given location ..., a species will try to move from areas with higher electrochemical potential to areas with lower electrochemical potential in equilibrium, the electrochemical potential will be constant everywhere ... say the ions have electric potential energy , and are moving to lower their potential energy. Likewise ... potential which is higher in the high concentration areas, and the molecules move to lower their chemical potential. These two examples show that an electrical potential and a chemical potential can both ... them into a single potential , the electrochemical potential , which can directly give the net redistribution ... for example, two glasses of water have the same electrochemical potential for a certain chemical species ... . If the chemical potential is the same in the two regions, the species will occasionally move back ... potentials of the two regions are different, more molecules will move to the lower chemical potential ... to the electrochemical potential difference between the two regions. Conflicting terminologies ... potential and electrochemical potential of an electron . However, for example, Solid State Physics ... used, where the chemical potential of an electron is by definition constant across a device in equilibrium while the electrochemical potential is equal to the chemical potential minus the local electric potential energy of an electron. This article uses the electrochemistry definitions. Definition and usage In generic terms, electrochemical potential is the mechanical work done in bringing 1 mole of an ion from a standard state to a specified concentration and electrical potential . By an IUPAC ... more details
about a form of energy in physics the statistical method Potential energy statistics Classical mechanics Refimprove date June 2010 In physics , potential energy is the energy stored in a body or in a system ... SI unit of measure for energy and work is the Joule symbol J . The term potential energy was coined ... publisher The University of Chicago Press year 1998 isbn 0 226 76420 6 ref Overview Potential energy ... as potential energy. If the spring is released or the mass is dropped, this stored energy will be converted ... climbs a hill it has potential energy. At the very top of the hill is its maximum potential energy. When the car speeds down the hill potential energy turns into kinetic. Kinetic energy is greatest at the bottom. The more formal definition is that potential energy is the energy difference between ... types of potential energy, each associated with a particular type of force . More specifically, every conservative force gives rise to potential energy. For example, the work of an Elasticity physics elastic force is called elastic potential energy work of the gravitational force is called gravitational potential energy work of the Coulomb force is called electric potential energy work of the strong ... potential energy work of intermolecular forces is called intermolecular potential energy. Chemical potential energy, such as the energy stored in fossil fuels , is the work of the Coulomb force ... usually has two components the kinetic energy of random motions of particles and the potential ... ,W Delta U math where math Delta U math is the change in the potential energy associated with that particular force. Common notations for potential energy are U , V , E sub p sub , and PE . Reference level The potential energy is a function of the state a system is in, and is defined relative ... reference state could be used, therefore it can be chosen based on convenience. Typically the potential ... state can also be expressed in terms of relative positions. Gravitational potential energy Main ... more details
Water potential is the potential energy of water per unit volume relative to pure water in reference conditions. Water potential quantifies the tendency of water to move from one area to another due to osmosis , gravity , mechanical pressure , or matrix effects such as surface tension . Water potential ... potential is typically expressed in potential energy per unit volume and very often is represented by the Greek letter math Psi math . Water potential integrates a variety of different potential ... systems, it is common for many potential factors to be important. For example, the addition of solutes to water lowers the water s potential makes it more negative , just as the increase in pressure increases its potential makes it more positive . If possible, water will move from an area of higher water potential to an area that has a lower water potential. One very common example is water ... potential of the solution. Components of water potential Many different factors may affect the total water potential, and the sum of these potentials determines the overall water potential and the direction ... correction, math Psi pi math is the Solution solute potential, math Psi p math is the pressure component, math Psi s math is the gravity gravimetric component, math Psi v math is the potential due to humidity , and math Psi m math is the potential due to matrix effects e.g., fluid cohesion and surface tension. All of these factors are quantified as potential energies per unit volume, and different ... condition is typically defined as pure water at the soil surface. Pressure Potential Pressure potential is based on mechanical pressure, and is an important component of the total water potential within plant cell biology cell s. Pressure potential is increased as water enters a cell. As water ... to keep its rigidity. Without turgor, plants lose structure and wilting wilt . The pressure potential in a living plant cell is usually positive. In Plasmolysis plasmolysed cells , pressure potential ... more details
about the general concept in the mathematical theory of vector fields the vector potential in electromagnetism Magnetic vector potential the vector potential in fluid mechanics Stream function In vector calculus , a vector potential is a vector field whose Curl mathematics curl is a given vector field. This is analogous to a scalar potential , which is a scalar field whose negative gradient is a given vector field. Formally, given a vector field v , a vector potential is a vector field A such that math mathbf v nabla times mathbf A . math If a vector field v admits a vector potential A , then from the equality math nabla cdot nabla times mathbf A 0 math divergence of the Curl mathematics curl is zero one obtains math nabla cdot mathbf v nabla cdot nabla times mathbf A 0, math which implies that v must be a solenoidal vector field . An interesting question is then if any solenoidal vector field admits a vector potential. The answer is affirmative, if the vector field satisfies certain conditions. Theorem Let math mathbf v mathbb R 3 to mathbb R 3 math be a solenoidal vector field which is twice smooth function continuously differentiable . Assume that v x decreases sufficiently fast as x . Define math mathbf A mathbf x frac 1 4 pi nabla times int mathbb R 3 frac mathbf v mathbf y left mathbf x mathbf y right , d mathbf y . math Then, A is a vector potential for v , that is, math nabla times mathbf A mathbf v . math A generalization of this theorem is the Helmholtz decomposition which states that any vector field can be decomposed as a sum of a solenoidal vector field and an irrotational vector field . Nonuniqueness The vector potential admitted by a solenoidal field is not unique. If A is a vector potential for v , then so is math mathbf A nabla m math where m is any continuously ... Magnetic potential Solenoid References Fundamentals of Engineering Electromagnetics by David K. Cheng, Addison Wesley, 1993. Category Fundamental physics concepts Category Potential Category Vector ... more details
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