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electromagnetic wave (EMW)

As can be seen from the term electromagnetic wave, these are waves that consist of a combination of electric and magnetic waves and are described by field strength vectors. The letter "B" represents the magnetic field, the letter "E" the electric field.

Electric fields arise between two live poles, as in capacitors or antennas, magnetic fields arise by induction, for example in a current-carrying conductor or an inductor.

When capacitance and inductance are interconnected, electromagnetic waves occur whose electric and magnetic fields are perpendicular to each other. A special form of the electromagnetic wave is the transverse wave, the Transversal Electromagnetic Mode( TEM), which is formed in waveguides, among other things.

The electric and magnetic fields of electromagnetic waves

The electric and magnetic fields of electromagnetic waves

Electromagnetic waves are determined by their temporal and spatial propagation and by the period, frequency and wavelength. After they are detached from the antenna under certain conditions, they are radiated into space as free space waves from antennas. Detachment from the antenna occurs only when the characteristic impedance of the antenna is greater than the field characteristic impedance of 376 ohms (120 ohms x pi). In addition, the frequency of the carrier wave must be well above the audible range. The field wave propagates in free space at the speed of light.

Electromagnetic waves, like light, are subject to diffraction, refraction, reflection, polarization and interference.

Englisch: electromagnetic wave - EMW
Updated at: 02.01.2015
#Words: 222
Links: arsenic (As), field strength (F), magnetic field (H), induction, current
Translations: DE

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