Comment on “Magnetic Field Due to a Finite Length Current-Carrying Wire Using the Concept of Displacement Current”

2015 ◽  
Vol 53 (2) ◽  
pp. 68-68
Author(s):  
Joaquim Anacleto ◽  
J. M. Ferreira
Keyword(s):  
Magnetic Field ◽  
Finite Length ◽  
Displacement Current

scholarly journals Influence of Magnetic Field on the Peristaltic Flow of a Viscous Fluid through a Finite-Length Cylindrical Tube

2010 ◽  
Vol 7 (3) ◽  
pp. 169-176 ◽  
Author(s):  
S. K. Pandey ◽  
Dharmendra Tripathi
Keyword(s):  
Magnetic Field ◽  
Viscous Fluid ◽  
Transverse Magnetic Field ◽  
Finite Length ◽  
Flow Rate ◽  
Hartmann Number ◽  
Volume Flow Rate ◽  
Critical Value ◽  
Transverse Magnetic ◽  
Volume Flow

The paper presents an analytical investigation of the peristaltic transport of a viscous fluid under the influence of a magnetic field through a tube of finite length in a dimensionless form. The expressions of pressure gradient, volume flow rate, average volume flow rate and local wall shear stress have been obtained. The effects of the transverse magnetic field and electrical conductivity (i.e. the Hartmann number) on the mechanical efficiency of a peristaltic pump have also been studied. The reflux phenomenon is also investigated. It is concluded, on the basis of the pressure distribution along the tubular length and pumping efficiency, that if the transverse magnetic field and the electric conductivity increase, the pumping machinery exerts more pressure for pushing the fluid forward. There is a linear relation between the averaged flow rate and the pressure applied across one wavelength that can restrain the flow due to peristalsis. It is found that there is a particular value of the averaged flow rate corresponding to a particular pressure that does not depend on the Hartmann number. Naming these values ‘critical values’, it is concluded that the pressure required for checking the flow increases with the Hartmann number above the critical value and decreases with it below the critical value. It is also inferred that magneto-hydrodynamic parameters make the fluid more prone to flow reversal. The conclusion applied to oesophageal swallowing reveals that normal water is easier to swallow than saline water. The latter is more prone to flow reversal. A significant difference between the propagation of the integral and non-integral number of waves along the tube is that pressure peaks are identical in the former and different in the latter cases.

Nonaxisymmetric flow in a finite-length cylinder with a rotating magnetic field

1999 ◽  
Vol 11 (7) ◽  
pp. 1821-1826 ◽  
Author(s):  
L. Martin Witkowski ◽  
J. S. Walker ◽  
P. Marty
Keyword(s):  
Magnetic Field ◽  
Finite Length ◽  
Rotating Magnetic Field

scholarly journals The influence of the earth's magnetic field on electric transmission in the upper atmosphere

1928 ◽  
Vol 121 (787) ◽  
pp. 260-285 ◽  
Keyword(s):  
Magnetic Field ◽  
Upper Atmosphere ◽  
Displacement Current ◽  
Philosophical Magazine ◽  
Electric Transmission ◽  
Joseph Larmor ◽  
Velocity Of Propagation ◽  
The Waves ◽  
A Current ◽  
Exciting Wave

In the ‘Philosophical Magazine’ for December, 1924, Sir Joseph Larmor showed how wireless waves can be transmitted to great distances, round the protuberance of the curved earth, and without excessive damping, if the transmission takes place in an ionised region high in the ultra-rarefied upper atmosphere, in which the number of effective ions increases upwards. Under the influence of the waves the ions oscillate, and thus produce a current which must be added, in the electrodynamic equations of the exciting wave, to the aetherial displacement current. The velocity of propagation is thus altered to c ', where c ' -2 = c -2 (1-4 π N e 2 c 2 / mp 2 )

scholarly journals VII. On the fundamental formulations of electrodynamics

1920 ◽  
Vol 220 (571-581) ◽  
pp. 207-245 ◽  
Keyword(s):  
Magnetic Field ◽  
Magnetic Force ◽  
Electromagnetic Interaction ◽  
Good Deal ◽  
Magnetic Polarity ◽  
Displacement Current ◽  
Linear Induction ◽  
Energy Relations ◽  
The Magnetic Field ◽  
Effective Representation

1. Modern electrical theory based on Maxwell’s concept of an æthereal displacement current, is generally regarded as being sufficiently complete in itself to cover all actions so far revealed to us, if we exclude those intra-atomic phenomena which probably involve some additional but not necessarily inconsistent action in their working. There, still, however exists a good deal of uncertainty as to the actual results of the development of this theory in certain directions, and no account has yet been taken of the great degree of latitude allowed by it in its simplest and most general form. For example, in most presentations of the theory of energy streaming in the electromagnetic field the discussion is given in a way which might lead one to believe that Poynting’s form of the theory is the only one conceivable. A single alternative has on one occasiont been suggested, but rather as an improvement on Poynting’s form than as an indication of its uncertainty. Whilst it cannot be denied that Poynting’s theory is probably the most appropriate one yet formulated, yet it must be recognised that there are an infinite number of fundamentally different forms each of which is itself perfectly consistent with Maxwell’s theory as expressed in his differential equations of electromagnetic interaction. Again, but now we are on a different plane, it has usually been stated that Maxwell’s theory is not of sufficient generality to cover the cases where there exists the complication of non-linear induction in ferromagnetic media. This view appears to have originated with the idea that the magnetic force is the fundamental æthereal vector of the magnetic field, whereas, as a matter of fact, the only consistent view of the energy relations of such a field leads to the conclusion that the magnetic induction is the true æthereal vector, the magnetic force being an auxiliary vector derived in the process of averaging the minute current whirls into their effective representation as a distribution of magnetic polarity.

Magnetic field created by a conducting cylindrical shell of finite length

2016 ◽  
Vol 99 (3) ◽  
pp. 979-986 ◽  
Author(s):  
J. M. Ferreira ◽  
Joaquim Anacleto
Keyword(s):  
Magnetic Field ◽  
Cylindrical Shell ◽  
Finite Length

scholarly journals Fast magnetic energy dissipation in relativistic plasma induced by high order laser modes

2016 ◽  
Vol 4 ◽  
Author(s):  
Y. J. Gu ◽  
Q. Yu ◽  
O. Klimo ◽  
T. Zh. Esirkepov ◽  
S. V. Bulanov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Magnetic Energy ◽  
Collisionless Plasma ◽  
High Energy ◽  
Field Energy ◽  
Displacement Current ◽  
Particle In Cell ◽  
Magnetic Field Energy ◽  
High Energy Electrons

Fast magnetic field annihilation in a collisionless plasma is induced by using TEM(1,0) laser pulse. The magnetic quadrupole structure formation, expansion and annihilation stages are demonstrated with 2.5-dimensional particle-in-cell simulations. The magnetic field energy is converted to the electric field and accelerate the particles inside the annihilation plane. A bunch of high energy electrons moving backwards is detected in the current sheet. The strong displacement current is the dominant contribution which induces the longitudinal inductive electric field.

Sign in / Sign up

Export Citation Format

Share Document