we do not transmit an audio signal by just directly converting it into an electromagnetic wave of the same frequency. Give two reasons for this....
The reasons are:
i) An audio frequency (AF) signal does not possess enough energy (due to its low frequency range) to travel an appreciable distance from the antenna.
ii) Since the wavelength of AF signal is large, the height of antenna required for its transmission is so large that it is practically impossible to build such an antenna.