In a communication system operating at wavelength 800 nm, only one percent of source frequency is available as signal bandwith. The number of channels accomodated for transmitting TV signals of band width 6 MHz are (Take velocity of light c = 3 $$ \times $$ 10⁸m/s, h = 6.6 $$ \times $$ 10^$$-$$34 J-s)

A carrier wave of peak voltage 14 V is used for transmitting a message signal. The peak voltage of modulating signal given to achieve a modulation index of 80% will be :

A telephonic communication service is working at carrier frequency of 10 GHz. Only 10% of it is utilized for transmission. How many telephonic channels can be transmitted simultaneously if each channel requires a bandwidth of 5 kHz ?

The carrier frequency of a transmitter is provided by a tank circuit of a coil of inductance 49 $$\mu $$H and a capacitance of 2.5 nF. It is modulated by an audio signal of $$12$$ $$kHz.$$ The frequency range occupied by the side bands is :