question_answer

An audio signal of frequency \[{{v}_{a}}\] is to be transmitted as an electromagnetic wave (i) directly as such. (ii) through its use as the modulating signal on a carrier wave of frequency \[{{v}_{c}}\]. State the ratio of the size of the transmitting antenna, that can properly sense the time variation of the signal, in terms of \[{{v}_{a}}\] and \[{{v}_{c}}\].                         

Answer:

                Size of antenna \[\propto \frac{1}{\text{Frequecny}}\]                 \[\therefore \] Required ratio \[={{v}_{c}}:{{v}_{a}}\]