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SOLUTION OF BASIC EQUATIONS OF ELECTRODYNAMICS                          175







                 X-axis



















                    Z-axis  Z > 0          Origin      Z < 0       Z-axis
                             Figure 4.1.5 Vector potential in space-time domain

            2.  Comparing Figure 4.1.3 and 4.1.4 one more time we realize that the vector potential wave
               oscillates up-and-down at right angles to the direction of its propagation over  -axis.
               According to (4.19), (4.1) and (4.35) the EM fields associated with such transverse wave
               has only two components

                                              1              1   
                                          =   ×  =  �  �
                                                         0
                                              0     0     2 �    (4.41)
                                                            2
                                     1    2        
                                     = − �    � = −   = −
                                     0   0     0    2  0   2
                  Then according to (4.40) for the forward wave  ( − ) propagating in the positive
                                                      1
                  direction   > 0 we obtain
                                          +
                                          = − �  1   1 � = − �  1  1 �
                                                                0
                                                 0
                                                    0   ()   0   �      (4.42)
                                                   +
                                                   = − �  1 �
                                                         0
                                                             
                  while for the backward wave  ( + ) propagating in the negative direction   < 0
                                        2
                                                   −      1  2
                                                  =  �  �
                                                       0
                                                                �                  (4.43)
                                                           0 
                                                   −
                                                  = − �  2 �
                                                         0
                                                            
            3.  According to (4.42) and (4.43) the ratio   =   = 377 Ohms. Therefore, the electric
                                                  ⁄
                                                 
                                                    
                                                         0
               and magnetic field oscillations are perfectly synchronized in space-time domain.
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