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Instituto Nacional de Astrofísica, Óptica y Electrónica INAOE. Propedéutico de la coordinación de Óptica. Teoría electromagnética. Teoría electromagnética. La carga eléctrica El campo eléctrico El potencial eléctrico La ley de Gauss La capacitancia y la corriente eléctrica
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Teoría electromagnética La carga eléctrica El campo eléctrico El potencial eléctrico La ley de Gauss La capacitancia y la corriente eléctrica Los campos eléctricos en la materia El campo magnético Los campos magnéticos en la materia La ley de Ampere La inducción y la inductancia Las ecuaciones de Maxwell Las ondas electromagnéticas
La teoría electromagnética • VI. Los campos eléctricos en la materia • 1. Los conductores, los semiconductores y los dieléctricos • 2. La polarización • 3. Generalización de la ley de Gauss • 4. Campo producido por un dieléctrico polarizado • 5. Las condiciones de frontera en los dieléctricos • 6. La energía del campo electrostático en los medios materiales
La permitividad eléctrica In electromagnetism, permittivity or absolute permittivity, usually denoted by the Greek letter ε (epsilon), is the measure of resistance that is encountered when forming an electric field in a particular medium. More specifically, permittivity describes the amount of charge needed to generate one unit of electric flux in a particular medium. Accordingly, a charge will yield more electric flux in a medium with low permittivity than in a medium with high permittivity. Thus, permittivity is the measure of a material's ability to resist an electric field, not its ability to ‘permit’ it (as the name ‘permittivity’ might seem to suggest). The permittivity of a dielectric medium is often represented by the ratio of its absolute permittivity to the electric constant. This dimensionless quantity is called the medium’s relative permittivity (εr) or dielectric constant (κ). https://en.wikipedia.org/wiki/Permittivity
La permitividad eléctrica: Medición • The dielectric constant of a material can be found by a variety of static electrical measurements. The complex permittivity is evaluated over a wide range of frequencies by using different variants of dielectric spectroscopy, covering nearly 21 orders of magnitude from 10−6 to 1015hertz. Also, by using cryostats and ovens, the dielectric properties of a medium can be characterized over an array of temperatures. In order to study systems for such diverse excitation fields, a number of measurement setups are used, each adequate for a special frequency range. • Various microwave measurement techniques are outlined in Chen et al.. Typical errors for the Hakki-Coleman method employing a puck of material between conducting planes are about 0.3%.[15] • Low-frequency time domain measurements (10−6 to 103 Hz) • Low-frequency frequency domain measurements (10−5 to 106 Hz) • Reflective coaxial methods (106 to 1010 Hz) • Transmission coaxial method (108 to 1011 Hz) • Quasi-optical methods (109 to 1010 Hz) • Terahertz time-domain spectroscopy (1011 to 1013 Hz) • Fourier-transform methods (1011 to 1015 Hz) • At infrared and optical frequencies, a common technique is ellipsometry. Dual polarisation interferometry is also used to measure the complex refractive index for very thin films at optical frequencies.https://en.wikipedia.org/wiki/Permittivity#Measurement
La energía del campo electrostático en los medios materiales