Where E is the unit vector of electric field intensity, H is the unit vector of magnetic field intensity, and S is the magnitude of wave vector, which indicates the propagation speed of electromagnetic wave. In the process of electromagnetic wave propagation, the direction of wave vector is always perpendicular to the direction of electric field and magnetic field, and its magnitude is related to the amplitude of electric field and magnetic field. ?
The concept of wave vector is an important basis for studying the propagation characteristics of electromagnetic waves, and it is widely used in electromagnetics, optics and other fields.
In electromagnetic wave propagation, the magnitude and direction of wave vector will change with the change of propagation medium, so it is very important to study wave vector, which can help us better understand the propagation law and characteristics of electromagnetic wave.
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