scholarly journals On Reactive Force in Thin Unclosed Conductor and Displacement Current

2021 ◽  
Vol 3 (5) ◽  
pp. 7-10
Author(s):  
Sergey A. Gerasimov
Keyword(s):  
Magnetic Field ◽  
Electric Current ◽  
Electromagnetic Fields ◽  
Momentum Density ◽  
Linear Momentum ◽  
The Self ◽  
Displacement Current ◽  
Reactive Force ◽  
Self Force ◽  
The Magnetic Field

The linear momentum density carried by electromagnetic fields creates the hidden force acting on the displacement current between ends of an unclosed conductor with alternative electric current. This force compensates the self-force exerted by the unclosed conductor with zero thin. The magnetic field produced by displacement current does not contribute to the force acting on the conductor. The unclosed conductor can move under action of the self-force. At small heights of cylindrical open conductor, the reactive force equivalent to the self-force becomes very large

Dynamics of a Conductor with Unclosed Alternative Electric Current

2021 ◽  
Vol 64 (6) ◽  
pp. 12-15
Author(s):  
Sergey Gerasimov ◽  
Keyword(s):  
Electric Current ◽  
Displacement Current ◽  
Thin Ring ◽  
Alternating Electric Current ◽  
Flat Ring ◽  
Conservation Of Momentum ◽  
Current Flows ◽  
Displacement Currents ◽  
Self Force ◽  
The Magnetic Field

The ponderomotive interaction of displacement currents and conduction currents in an open conductor through which an alternating electric current flows is considered. The calculation is performed for a flat conductor of arbitrary shape. It has been shown that the displacement current does not create a nonzero force that would act on an open conductor. The so-called force of self-action, with which the conductor acts on itself, is compensated by the force of Abraham, transmitted to the electromagnetic field. The absolutely exact fulfillment of the law of conservation of momentum, which includes the latent momentum of the field, has been demonstrated. The density of Abraham's force is determined by the vector product of the derivative of the electric field in-duction by the magnetic field induction. As an example, a numerical calculation of the self-force and the Abraham force for a thin ring conductor is carried out. The ratio of Abraham's force to the square of the conduction current depends only on the relative dimensions of the conductor. The maximum Abraham's force is observed for a conductor representing half of a flat ring.

scholarly journals Sensitivity of Planaria to Weak, Patterned Electric Current and the Subsequent Correlative Interactions with Fluctuations in the Intensity of the Magnetic Field of Earth

J ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 79-89
Author(s):  
Victoria Hossack ◽  
Michael Persinger ◽  
Blake Dotta
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Electric Current ◽  
Electromagnetic Fields ◽  
Linear Correlation ◽  
Small Proportion ◽  
Weak Electric Field ◽  
Electric And Magnetic Fields ◽  
The Magnetic Field ◽  
Highly Evolved

Some species of fish show highly evolved mechanisms by which they can detect exogenous electric and magnetic fields. The detection of electromagnetic fields has been hypothesized to exist in humans, despite the lack of specialized sensors. In this experiment, planaria were tested in a t-maze with weak electric current pulsed in one arm to determine if the planaria showed any indication of being able to detect it. It was found that a small proportion of the population seemed to be attracted to this current. Additionally, if the experiment was preceded by a geomagnetic storm, the planaria showed a linear correlation increase in the variability of their movement in response to the presence of the weak electric field. Both of these results indicate that a subpopulation of planaria show some ability to respond to electromagnetic fields.

CONTINUATION OF ELECTROMAGNETIC FIELDS—II

Geophysics ◽  
1969 ◽  
Vol 34 (4) ◽  
pp. 572-583 ◽  
Author(s):  
Amalendu Roy
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Electromagnetic Fields ◽  
Vertical Component ◽  
Ground Surface ◽  
Static Field ◽  
Downward Continuation ◽  
Displacement Current ◽  
Grid Spacing ◽  
The Magnetic Field

Given the values observed on a plane parallel to a horizontal ground surface, solutions are obtained for the continuation of dynamic electromagnetic fields upward in air or downward into a conducting earth. The upward (away from secondary sources) continuation integrals for the real and imaginary parts of any electromagnetic field component with arbitrary frequency and in a medium with arbitrary electrical and magnetic constants are derived and simplified to the case where the conductivity is zero. However, for frequencies normally used in electromagnetic prospecting, the effect of displacement current is negligible and one does not need to use the rigorous formulas derived, because adequate accuracy can be obtained by using the simpler static field formulas for continuation in a nonconducting medium such as air. The central problem in electromagnetic continuation is one of extrapolating the observed field from one medium to another through a physical boundary, namely, the air‐earth interface. From the magnetic field observed in air, one should be able to compute the same within the conducting earth. Conversely, from the electric field observed within the ground or on its surface, one should be in a position to calculate the same in air and also, of course, deeper into the ground. The continuity conditions for the vertical derivatives of the electromagnetic field components, which constitute the basis for continuing an electromagnetic field from one medium to another, are derived. Downward continuation formulas, suitable for practical use, are derived explicitly, through use of a Taylor expansion, for the vertical component of the magnetic field in air, this being the quantity which is commonly measured. Three‐dimensional downward continuation formulations to depths of one and two units of grid spacing and two‐dimensional continuation to a depth of one unit of grid spacing are derived under the assumption that the effect of displacement current can be neglected.

scholarly journals The effect of simplifications of a numerical mesh on the results of electromagnetic analysis of the Nuclotron-type cable

2018 ◽  
Vol 177 ◽  
pp. 08004
Author(s):  
Łukasz Tomków
Keyword(s):  
Magnetic Field ◽  
Electric Current ◽  
Current Density ◽  
Electric Current Density ◽  
Electromagnetic Analysis ◽  
First Case ◽  
Single Region ◽  
The Magnetic Field

The model of a single Nuclotron-type cable is presented. The goal of this model is to assess the behaviour of the cable under different loads. Two meshes with different simplifications are applied. In the first case, the superconductor in the cable is modelled as single region. Second mesh considers individual strands of the cable. The significant differences between the distributions of the electric current density obtained with both models are observed. The magnetic field remains roughly similar.

scholarly journals The hall effect in liquid electrolytes

1913 ◽  
Vol 88 (606) ◽  
pp. 588-604 ◽  
Keyword(s):  
Magnetic Field ◽  
Hall Effect ◽  
Electric Current ◽  
Metal Plate ◽  
Satisfactory Explanation ◽  
Thermo Electric ◽  
Field Independent ◽  
Set Up ◽  
The Magnetic Field ◽  
Thin Metal Plate

The distortion of the lines of flow of an electric current in a thin metal plate by the action of a magnetic field was discovered in 1879. Hall attributed this to the action of the magnetic field on the molecular currents in the metal film, which were deflected to one side or the other and accompanied by a corresponding twist of the equipotential lines. This explanation did not pass without criticism, and another theory of the effect found by Hall was published in 1884. In that paper the author seeks to explain the effect by assuming a combination of certain mechanical strains and Peltier effects, a thermo-electric current being set up between the strained and the unstrained portions. The effect of such strain was to produce a reverse effect in some metals, and these were precisely the metals for which the Hall effect was found to reverse. Aluminium was the only exception. In other respects, however, as shown by Hall in a later paper, Bidwell's theory did not stand the test of experiment, and the results lend no support to his theory, while they are in complete accordance withe the explanation that the molecular currents are disturbed by the action of the magnetic field. On the electron theory of metallic conduction, the mechanism of the Hall effect is more obvious, but at present no satisfactory explanation of the reversal found in some metals is known. Further experiments have made it clear that there is a real deflection of the elementary currents, due to the application of the magnetic field, independent of any effect due to strain.

Effects of Electromagnetic Fields on the Quantum Yield of Free Radicals in Cryptochrome

2019 ◽  
Vol 953 ◽  
pp. 127-132
Author(s):  
Yu Ling Chen ◽  
Du Yan Geng ◽  
Chuan Fang Chen
Keyword(s):  
Magnetic Field ◽  
Electromagnetic Field ◽  
Free Radicals ◽  
Free Radical ◽  
Quantum Yield ◽  
Electromagnetic Fields ◽  
Applied Magnetic Field ◽  
Geomagnetic Field ◽  
Quantum Biology ◽  
The Magnetic Field

In this paper, the effects of the quantum yield of free radicals in cryptochrome exposed to different electromagnetic fields were studied through the quantum biology. The results showed that the spikes characteristics was produced in the free radicals in cryptochrome, when it exposed to the applied magnetic field (ω = 50 Hz, B0 = 50 μT). The spikes produced by the electromagnetic field was independent of the changes of polar θ. When the frequency of the magnetic field increased, the spikes characteristics produced in unit time also increased. These results showed that the environmental electromagnetic field could affect the response of organisms to the geomagnetic field by influencing the quantum yield in the mechanism of free radical pair.It provided a basis for studying the influence of environmental electromagnetic field on biology, especially the navigation of biological magnetism.

The equilibrium configuration of a slowly rotating mass of liquid in the presence of a poloidal magnetic field

1972 ◽  
Vol 55 (1) ◽  
pp. 105-112
Author(s):  
C. Sozou
Keyword(s):  
Magnetic Field ◽  
Electric Current ◽  
Equilibrium Configuration ◽  
Spherical Surface ◽  
Perturbation Expansion ◽  
Reverse Direction ◽  
Poloidal Magnetic Field ◽  
Inviscid Liquid ◽  
Axis Of Rotation ◽  
The Magnetic Field

The equilibrium configuration of a slowly rotating self-gravitating perfectly conducting inviscid liquid, in the presence of a small poloidal magnetic field, is considered for a case where the electric current is a simple function of the distance from the axis of rotation. Owing to the coupling of the magnetic field with the rotation the electric current may reverse direction. This could make the magnetic field zero on certain surfaces and impose restrictions on the parameters of the problem. A perturbation expansion of the nearly spherical surface of the liquid is constructed.

Numerical study of toroidal magnetic field on the self-gravitating protoplanetary disks

2020 ◽  
Vol 29 (09) ◽  
pp. 2050067
Author(s):  
Hanifeh Ghanbarnejad ◽  
Maryam Ghasemnezhad
Keyword(s):  
Magnetic Field ◽  
Accretion Disks ◽  
Numerical Solutions ◽  
Numerical Study ◽  
Ohmic Heating ◽  
The Self ◽  
Toroidal Magnetic Field ◽  
Heating Process ◽  
Heating And Cooling ◽  
The Magnetic Field

In this paper, we study the self-gravitating accretion disks by considering the toroidal component of magnetic field, [Formula: see text] and wind/outflow in the flow and also investigate the effect of two parameters, [Formula: see text] and [Formula: see text] corresponding to magnetic field on the latitudinal structure of such accretion disks. The cooling of the disk is parameterized simply as, [Formula: see text] (where [Formula: see text] is the internal energy and [Formula: see text] is the cooling timescale and [Formula: see text] is a free constant) and the heating rate is decomposed into two components, magnetic field and viscosity dissipations. We have shown that when the toroidal magnetic field becomes stronger, the heating process (viscous and resistivity) and the radiative cooling rate increase. Ohmic heating is much bigger than viscous heating and cooling, so we must consider the role of the magnetic field in the energy equation. Our numerical solutions show that the thickness of the disk decreases with strong toroidal component of magnetic field. The magnetic field leads to production of the outflow in the low latitude. So, by increasing the toroidal component of the magnetic field, the regions which belong to inflow decrease and the disk is cooled.

scholarly journals Magnetic Field Generated during Electric Current-Assisted Sintering: From Health and Safety Issues to Lorentz Force Effects

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1653
Author(s):  
Huaijiu Deng ◽  
Jian Dong ◽  
Filippo Boi ◽  
Theo Saunders ◽  
Chunfeng Hu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Electric Current ◽  
Lorentz Force ◽  
Health And Safety ◽  
Interparticle Contact ◽  
Safety Issues ◽  
Contact Points ◽  
The Magnetic Field ◽  
Health And Safety Issues

In the past decade, a renewed interest on electromagnetic processing of materials has motivated several investigations on the interaction between matter, electric and magnetic fields. These effects are primarily reconducted to the Joule heating and very little attention has been dedicated to the magnetic field contributions. The magnetic field generated during electric current-assisted sintering has not been widely investigated. Magnetism could have significant effects on sintering as it generates significant magnetic forces, resulting in inductive electrical loads and preferential heating induced by overlapping magnetic fields (i.e., proximity effect). This work summarizes the magnetic field effects in electric current-assisted processing; it focuses on health and safety issues associated with large currents (up to 0.4 MA); using FEM simulations, it computes the self-generated magnetic field during spark plasma sintering (SPS) to consolidate materials with variable magnetic permeability; and it quantifies the Lorentz force acting at interparticle contact points. The results encourage one to pay more attention to magnetic field-related effects in order to engineer and exploit their potentials.

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