Electric field potential point charge

The Sect. 4.6.2 introduces a numerical scheme for calculating the potential distribution in the EDL of arbitrary clusters of spherical particles the singularity method (PhiUips 1995). This approach considers the total electric field in EDL as superposition of the electric fields of point charges, which are located inside the particles. Such a field is easily described by ... 

Isoelectric point is a pH value, at which electrokinetic potential C on the slip plane is equal to 0, at the participation in ion exchange only of protons H% i.e., in distilled and deionized water. In Western literature it is denoted pi or lEP. Isoelectric point of a mineral is determined by the electrokinetic method, i.e., from the pH value, at which a suspension of its particles has the lowest mobility in the electric field. Isoelectric point. As opposed to the zero charge point, isoelectric point characterizes zero charge of hydrodynamic interface, i.e., conditions when 0. 

The magnitude of potential of bubbles immersed in solutions of electrolytes are monotonously depressed by increasing the concentration of the mono- or divalent salts dissolved in the solutions. This behavior is attributed to the screening of the interactions between the applied electric field and the charged bubbles, induced by the salts. They also decrease as the acidity of the immersing solution increases. This decrease is all the more pronounced as the salinity is lower. For aU the authors, the isoelectric point ranges (or would range by extrapolation) from pH 1.5 to 3. 

The electric field intensity 5 at a point represents the force acting on a unit positive point charge (probe charge) S = —VK, where V stands for the electric field potential energy at this point. When the potential changes linearly in space... 

A convenient starting point for discussion of transport properties in electrolytes is a consideration of the physical laws which connect charge and electric potential. In a medium of uniform dielectric constant we may write Poisson s equation, which connects the gradient of the electric field with the charge density... 

Wlien an electrical coimection is made between two metal surfaces, a contact potential difference arises from the transfer of electrons from the metal of lower work function to the second metal until their Femii levels line up. The difference in contact potential between the two metals is just equal to the difference in their respective work fiinctions. In the absence of an applied emf, there is electric field between two parallel metal plates arranged as a capacitor. If a potential is applied, the field can be eliminated and at this point tire potential equals the contact potential difference of tlie two metal plates. If one plate of known work fiinction is used as a reference electrode, the work function of the second plate can be detennined by measuring tliis applied potential between the plates [ ]. One can detemiine the zero-electric-field condition between the two parallel plates by measuring directly the tendency for charge to flow through the external circuit. This is called the static capacitor method [59]. 

Static electricity hazards and nuisances are typified by the generation of large potentials (0.1-100 kV) by small charging currents (0.01-100 pA) flowing in high resistance circuits (10 -10 Q). This in part differentiates static electricity from other electrical phenomena. For example, stray currents in low resistance circuits are typically of the order 1 A for potential differences of the order 1 volt (A-4-1.3). The electric field at any point in relation to a conductor is proportional to its potential, while magnetic field is proportional to... 

Just as it is useful to replace the force between two point charges by their mutual potential energy U. so we can replace the electric field by a more general quantity called the electmstatic potential . This is related to E in the same way that U is related to F... 

Electric pofcTidfff, ), potential difference, or electromotive force (emf, E, e) have units of volts and refer to the energy change when a charge is moved from one point to another m an electric field. 

When inserting into (4.5), the term ZeR will be multiplied with the elements of the electric field gradient tensor V. Fortunately, the procedure can be restricted to diagonal elements Vu, because V is symmetric and, consequently, a principal axes system exists in which the nondiagonal elements vanish, = 0. The diagonal elements can be determined by using Poisson s differential equation for the electronic potential at point r = 0 with charge density (0), AV = Anp, which yields... 

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