What is 'amplitude modulation'? Represent the process graphically. Write the limitation of amplitude modulation. 

In amplitude modulation, the amplitude of the carrier wave is varied in accordance with the amplitude of the audio frequency modulating signal.
In this case, the frequency of the amplitude modulated wave remains the same as that of the carrier wave. 




Limitation of amplitude modulation:

1. The amplitude of modulated signal obtaind can be transmitted only by amplifying it first and then fed to an antenna of appropriate size for radiation. 
The size of the antenna matters.