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A dipole is characterised by its dipole moment, a vector quantity shown in the figure as the blue arrow labeled M. It is the relationship between the electric field and the dipole moment that gives rise to the behaviour of the dielectric. (Note that the dipole moment points in the same direction as the electric field in the figure.
The monopole antenna is essentially one half of the half-wave dipole, a single 1 / 4 wavelength element with the other side connected to ground or an equivalent ground plane (or counterpoise). Monopoles, which are one-half the size of a dipole, are common for long-wavelength radio signals where a dipole would be impractically large.
Eddy currents are minimized in these devices by selecting magnetic core materials that have low electrical conductivity (e.g., ferrites or iron powder mixed with resin) or by using thin sheets of magnetic material, known as laminations. Electrons cannot cross the insulating gap between the laminations and so are unable to circulate on wide arcs.
[1] [2] [3] For example, if a 1 m 3 solid cube of material has sheet contacts on two opposite faces, and the resistance between these contacts is 1 Ω, then the resistivity of the material is 1 Ω⋅m. Electrical conductivity (or specific conductance) is the reciprocal of electrical resistivity. It represents a material's ability to conduct ...
The corresponding energy transfer requires or generates a voltage. A mechanical analogy in the K = 1 case with magnetic field energy (1/2)Li 2 is a body with mass M, velocity u and kinetic energy (1/2)Mu 2. The rate of change of velocity (current) multiplied with mass (inductance) requires or generates a force (an electrical voltage).
--ParkerHiggins 03:17, 1 December 2005 (UTC) Yes, if you already have an oscillator circuit you could replace the resistor with a slide potentiometer. Or even simpler, you could just add the potentiometer in parallel with the resistor, which wouldn't require breaking the original circuit. —Keenan Pepper 15:24, 1 December 2005 (UTC)
Because the solutes are charged ions they also increase the electrical conductivity of the solution. [86] The increased ionic strength reduces the thickness of the electrical double layer around colloidal particles, and therefore the stability of emulsions and suspensions. [87] The chemical identity of the ions added is also important in many uses.