194 



PIEKCE. 



where 



c = velocity of light, 



Xo= natural wavelength of the antenna without inductance, 

 X = the wavelength with the inductance, 

 i = the current at the point P', 



/ = length measured along the antenna from the inductance to 

 the point P'. 



a 



Figure 1. 



The character of the assumed distribution is as follows: The factor 



27rc 

 sin -r- t means that the current is sinusoidal in time at every point 



of the antenna, with the angular velocity 



0} 



27r _ 2irc _ 2tc 



(2) 



The meaning of the other factor 



-^ sin y f - - / ) = / (say) 



(3) 



is illustrated in the diagrams (a), (b) and (c) of Figure 2. 



