SELF | 2 |
S.B. Karavashkin and O.N. Karavashkina |
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In this view, consider the acoustic field producing in a gas medium by the system of sources radiating in anti-phase, as shown in Fig. 1. According to the vector diagram presented in this figure, the resulting displacement of gas molecules is perpendicular to the propagation direction of the resulting acoustic wave. This effect is conditioned neither by viscosity nor by the presence of solid bounds, and it is not limited by the close region of acoustic near field. If the studied region was at a large distance r from the presented acoustic dipole, then for each half of dipole we can write [5, p.38]: |
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(5) |
where Summing (5) vectorially, we yield |
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(6) |
where |
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Thus, on one hand the resulting sound field remains potential, since it is produced by linear superposition of strongly potential fields, but on the other hand, the resulting velocity of molecules vibration is perpendicular to the wave propagation direction. Consequently, in the conventional viewpoint, this sound field, being vortical, cannot exist in gas medium. When studying electromagnetic fields, we see the contrary. As is known, just the transversal waves correspond to them, and the induction pair of Maxwell equations has non-zero right part for the region free of sources and currents: |
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(7) |
where c
is the light velocity in vacuum. At the same time, ''an electrical dipole whose charges
alternate in time under an extraneous source action can be presented as a system of two
metallic spheres connected by a conductor to whose middle the extraneous source is
included... The alternating charge is equivalent to the alternating current in the
connecting conductor. Due to it, the field produced by a variable-momentum electrical
dipole will coincide with the field produced by a l-long conductor in which the
extraneous current runs... Such dipole field radiation offers to solve the problems of
analysis and synthesis of antennas, as we can consider them as dipole systems'' [6,
pp.96-97]. The same, ''an oscillating dipole is equivalent to an antenna with the current J
= J0 cos In this paper we will show that these problems in many respects are caused by the difference between stationary and dynamical lines of force, which was studied by the example of divergence of vector in [10]. We can expect that the curl of vector determining the field to be solenoidal will reveal in dynamical cases the peculiarities different from those known - the peculiarities that up to now were disregarded, because the conventional vector algebra basic regularities were limited by stationary fields. |