FM & PM

Q.

An audio signal $u_m=20\sin 2\mathrm{\pi }\left(1500\mathrm{t}\right)$ modulates a carrier $u_c=80\sin 2\mathrm{\pi }\left(100000\mathrm{t}\right)$. The value of percent modulation is ________.

Q. The frequency of a FM transmitter without signal input is called

1. Lower side band frequency
2. Upper side band frequency
3. Resting frequency
4. None of these

Q. The carrier frequency generated by a tank circuit containing 1 nF capacitor and 10 $\mu$ H inductor is

1. 1592 Hz
2. 159.2 MHz
3. 159.2 kHz
4. 159.2 Hz

Q. In an AC circuit, the current is given by the equation, $i=2\sqrt{13}\sin \left(50\pi t\right)\text{A}$. Calculate the time taken to reach from zero $($at $t=0)$ to its first maximum value.

1. $5\text{ms}$
2. $10\text{ms}$
3. $20\text{ms}$
4. $100\text{ms}$

Q. The carrier frequency generated by a tank circuit containing 1 nF capacitor and 10 $\mu$ H inductor is

1. 1592 Hz
2. 159.2 MHz
3. 159.2 kHz
4. 159.2 Hz