In an $FM$ system, a $7 \ kHz$ signal modulates a $108 \ MHz$ carrier such that the frequency deviation is $50 \ kHz$. The carrier swing is: (in $kHz$)

In a modulation process where the pulse duration varies with the modulating signal,it is called ......

The modulation frequency of an $AM$ radio station is $250\, kHz$,which is $10\%$ of the carrier wave. If another $AM$ station approaches you for license,what broadcast frequency will you allot? (Note: The interval between two carrier frequencies should be at least two times the modulation frequency to avoid interference.)

Mean optical power launched into an $8 \ km$ fibre is $120 \ \mu W$ and mean output power is $4 \ \mu W$,then the overall attenuation is ....... $dB$ (Given $\log 30 = 1.477$)

For an amplitude-modulated wave, the audio frequency is $500 \, \text{cycles/second}$. What is the actual carrier frequency in $\text{cycles/sec}$?

If the highest modulating frequency of the wave is $5\, kHz$,the number of stations that can be accommodated in a $150\, kHz$ bandwidth are