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Electromagnetic wave velocity

Under vacuum, the velocity of propagation c of an electromagnetic wave is... [Pg.665]

This frequency is a measure of the vibration rate of the electrons relative to the ions which are considered stationary. Eor tme plasma behavior, plasma frequency, COp, must exceed the particle-coUision rate, This plays a central role in the interactions of electromagnetic waves with plasmas. The frequencies of electron plasma waves depend on the plasma frequency and the thermal electron velocity. They propagate in plasmas because the presence of the plasma oscillation at any one point is communicated to nearby regions by the thermal motion. The frequencies of ion plasma waves, also called ion acoustic or plasma sound waves, depend on the electron and ion temperatures as well as on the ion mass. Both electron and ion waves, ie, electrostatic waves, are longitudinal in nature that is, they consist of compressions and rarefactions (areas of lower density, eg, the area between two compression waves) along the direction of motion. [Pg.107]

The velocity of current or voltage waves in any medium is called the velocity of propagation of electricity in that medium. The velocity of electromagnetic waves (electricity) through a conductor is a measure of line or conductor parameters through which it propagates and is represented by... [Pg.564]

Velocity of propagation of electromagnetic waves — 3 X I o km/s (more accurate values are determined in Table 24.1 (b) for the line parameters considered). [Pg.790]

The most common form of energy deposition used for planar shock wave research has been electrical resistance heating of a metal foil which vaporizes, driving a flyer plate to a high velocity before it impacts a specimen. In a hybrid system incorporation both resistance vaporization and an electromagnetic push, velocities to 18 km/s are reported for kapton flyer plates which are... [Pg.53]

Figure 3.9. Electromagnetic particle velocity profiles in limestone at 12 GPa. Profiles indicate both the arrival of the shock wave and the release wave from the free surface (Murri et al., 1975). Figure 3.9. Electromagnetic particle velocity profiles in limestone at 12 GPa. Profiles indicate both the arrival of the shock wave and the release wave from the free surface (Murri et al., 1975).
Thermal radiation takes place by the emission of electromagnetic waves, at the velocity of light, from all bodies at temperatures above absolute zero. The heat flux from an... [Pg.346]

The first cosine factor represents a wave like the originals with average wavelength and frequency and moving with velocity (uq + us2)/ k + k2). In the case of electromagnetic waves u = cAq and w2 = cfc2j so that v = c(ki + k2)/(ki + k2) = c, the original velocity. The composite wave however, has an amplitude that varies within a profile defined by the factor... [Pg.120]

The velocity of electromagnetic waves through any material other than the vacuum is (e ) 2 = v and the ratio n = c/v is called the index of refraction of that material. It follows that n = y /x/eoMo and, since the ratio n/fio 1, except for ferromagnetic materials, the index of refraction is commonly defined as the square root of the dielectric constant, e/e0- Since the frequency of the field is not affected by the medium, refraction can be described equally well as a change of the wavelength of light passing between different transparent media. [Pg.137]

The number of times that an event or a periodic function repeats during a unit value of an independent variable, usually time. 2. For any periodic motion, the frequency, symbolized by r, is the number of repetitions (e.g., number of revolutions or cycles or oscillations of an electromagnetic wave) of some process occurring in a unit period of time. The SI unit for frequency, reciprocal second, is often referred to as a hertz (Hz). However, the term hertz should only be used in reference to cycles per second and not for radial (circular) frequency or angular velocity symbolized by (p (= 2777 ) and having SI units of rad-s h... [Pg.298]

Refractive index or index of refraction is the ratio of wavelength or phase velocity of an electromagnetic wave in a vacuum to that in the substance. It measures the amount of refraction a ray of light undergoes as it passes through a refraction interface. Refractive index is a useful physical property to identify a pure compound. [Pg.1094]

The effect of electromagnetic radiation on matter is to induce a dipole. In a transparent dielectric medium, only the velocity of electromagnetic radiation is reduced, depending on the refractive index of the medium, which is determined by its density. The propagation constant of electromagnetic waves is given by... [Pg.310]

Walter Kanfmarm also reported the determination of the charge-to-mass ratio of cathode rays (abont 10 emu g- ) in a paper he submitted in April 1897 (7). Kanfmarm also based his result on magnetic deflection measurements however, he concluded that the hypothesis of cathode rays as emitted particles could not explain his data. (One of the outstanding questions in the study of cathode rays in the late 1890s was whether they were particles or electromagnetic waves. Thomson and Kanfmarm were typical of their coimtrymen most British researchers leaned toward the particulate hypothesis and most Germans toward waves.) Today Kanfmarm is better known for his careful measurements of the velocity-dependent mass of the electron published over several years beginning in 1901 these results were later explained by special relativity. [Pg.74]

The interaction of a nucleus with the oscillating magnetic field B0, created by the electromagnetic wave, can be understood if it is assumed that it results from the composition of two half vectors, rotating in opposite directions in the xOy plane with identical angular velocities (Fig. 9.6). The vector rotating in the same direction as the precession is the only one that can interact with the nucleus. [Pg.134]

Propagation Delay of Lossless Lines. The minimum propagation delay (Tpd expressed in picoseconds per centimeter) for a unit length of lossless line is the inverse of the phase velocity (op) of the electromagnetic waves propagating through the dielectric medium surrounding the conductor line ... [Pg.469]

Radar techniques are based on the exploitation of three main properties of electromagnetic waves a) electromagnetic waves travel at the velocity of light so that the time interval between the transmission of a signal and its returning echo, divided by two and multiplied by the... [Pg.26]

Evidently, both forces change direction with time as the individual rays associated with the source and the sink rotate. Also, the wavenumber, Eq. (110), formally is the conventional expression of course, k describes propagation of the electromagnetic wave. However, the origin of angular velocity co is the rotation of the source. [Pg.375]


See other pages where Electromagnetic wave velocity is mentioned: [Pg.163]    [Pg.163]    [Pg.2854]    [Pg.370]    [Pg.665]    [Pg.109]    [Pg.565]    [Pg.790]    [Pg.808]    [Pg.56]    [Pg.56]    [Pg.400]    [Pg.98]    [Pg.620]    [Pg.57]    [Pg.6]    [Pg.1638]    [Pg.112]    [Pg.247]    [Pg.246]    [Pg.1684]    [Pg.18]    [Pg.24]    [Pg.196]    [Pg.427]    [Pg.109]    [Pg.759]    [Pg.1213]    [Pg.405]    [Pg.463]    [Pg.2]    [Pg.338]   
See also in sourсe #XX -- [ Pg.137 ]




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