SELF

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S.B. Karavashkin and O.N. Karavashkina

Similarly, if we take symmetric half-wave elementary oscillator and accurately match the wavelength of radiation with the length of oscillator, there will form the standing wave. We can think this oscillator the system of above pulsing sources located along the axis of oscillator, whose amplitude and phase of pulsation is synchronised in accordance with the parameters of standing wave, as we showed it in Fig. 2.

Fig. 2. Model of half-wave symmetric elementary oscillator shaped as a system of pulsing point sources

Indeed, if above the standing wave, in the oscillator is present also progressive wave, the analogy will be incomplete. However in this case the general process of radiation can be thought as a superposition of radiation of stationary point sources modelling this standing wave - and shifting sources modelling the progressive wave in the oscillator.

Thus, we see, this model of point potential pulsing source can serve as the basis for modelling real physical processes.

To study the E-field strength of considered point pulsing source in space surrounding it, we will divide the consideration into two stages.

At the first stage, let us think the charge of source time-invariable. At this condition the electric field strength is known to be

and directed along the radius-vector from the point source (either towards the source, dependently on the sign of charge). With it, "the gradient is in direction with the normal to the surface of the level that passes through the given point P₀  of the scalar field" [6, c. 88].

In other words, "gradient that relates to the point P₀   is the vector of maximal slope" [6, p. 84]. We will base on this definition as general in our study of dynamic field of point source.

Now let us consider the changes in (7) when the source pulsing. We will proceed from the short-range theory, according to which any field excitation is passed sequentially from point to point along the wave propagation, and the velocity of wave propagation in isotropic homogeneous space is constant and equal to   c  relatively the stationary reference frame.