Hall electric current

Now the effective conductivity ia the direction of the electric field is <7/(1 + /5 ), ie, the scalar conductivity reduced by a factor of (1 + /5 ) by the magnetic field. Also, the electric current no longer flows in the direction of the electric field a component j exists which is perpendicular to both the electric and magnetic fields. This is the Hall current. The conductivity in the direction of the Hall current is greater by a factor of P than the conductivity in the direction of the electric field. The calculation of the scalar conductivity starts from its definition ... 

The Hall Effect In the presence of an orthogonal magnetic field in the z-direction an x-directed electric current produces a y-directed gradient of the electrochemical potential. Similarly an x-directed thermal gradient produces a y-directed gradient of the electrochemical potential, known as the Nernst effect. 

Electrolysis, the process of using an electric current to bring about chemical change, is employed to produce sodium, chlorine, sodium hydroxide, and aluminum (Hall-Heroult process) and is used in electrorefining and electroplating. 

Hall process— A process for the production of aluminum metal by passing an electric current through a mixture of aluminum oxide dissolved in cryolite (sodium aluminum fluoride). 

Similarly to the Hall-based current sensing techniques, the simplest way to measure an electric current with MR devices is to sense the magnetic field around the current conducting wire directly. Since they are sensitive in the film-... 

The primary use of aluminum oxide is the manufacture of aluminum metal. When an electric current is passed through molten (melted) aluminum oxide, the compound breaks down to form aluminum metal and oxygen gas. The method is called the Hall process after the American chemist Charles Martin Hall who invented it. 

This generalized Ohm s law differs from the conventional one because it takes into account the electron pressure gradient and the [J B] term related to the Hall effect. Solution of equation (3-263) with respect to electric current is comphcated because the current is present in two terms. The generalized Ohm s law can be simplified if plasma condnctivity is high (a oo) ... 

Fig. 7.12 Schematic illustration of the photoredox events leading to the generation of electrical current via two-photon excitation of the dye-derivatised Ti02 electrodes coated with PSII particles. [After Rao and Hall et al.]...

The Hall effect, first reported in 1879 by Hall, is by far the best known of the various galvanothermomagnetic effects. In this case, if an electrical current is made to flow in a conductor perpendicular to a magnetic field, in addition to the transverse temperature gradient due to the Ettingshausen effect, one also observes a transverse electric field which is perpendicular to both the electrical current and the magnetic field (Fig. Ic). The Hall coefficient is defined by... 

Measurement of direct currents usually is by Hall-efiEect devices. The Hall effect is the development of a transverse electric field across a solid material when that material carries an electric current and is in a magnetic field with a component perpendicular to the current. The electric field results in a measurable potential difference, the Hall voltage, which is directly proportional to both the current and the magnetic field. Meters usually are accurate within 0.5%, supporting a four-digit readout. Most plants can control cell current within 1%. 

Ettinghausen s effect [VonEttinghausens] n. When an electric current flows across the lines of force of a magnetic field an electromotive force is observed which is at right angles to both the primary current and the magnetic field a temperature gradient is observed which has the opposite direction to the Hall electromotive force, hide DR (ed) (2004) CRC handbook of chemistry and physics. CRC Press, Boca Raton, FL. 

The Hall effect in magnetic materials exhibits a number of unusual features which have defied successful explanation until recently. Defining the Hall resistivity pH = EhU as the transverse Hall electric field per longitudinal current density, typical results for a magnetic material display an initial rapid linear rise of the Hall voltage with applied field followed by a second linear portion with a considerably smaller field coefficient this may be expressed as... 

Hall Effect Generation of a difference in potential across a conductor carrying an electric current that is exposed to an external magnetic field applied at a right angle. 

Superceram. Tableware containing added alumina, made by Hall China, USA. Superconductor. A material with virtually no resistance to the passage of electric current. 

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