During modulation,a transmitter supplies $9 \ kW$ to the antenna. Calculate the total power radiated during $40\%$ modulation in $kW$.

$A$ carrier signal of frequency $1.5 MHz$ has an amplitude of $50 V$. It is amplitude modulated by a modulating wave of frequency $10 kHz$ with a modulation index of $50 \%$. What are the frequencies of the $LSB$ and $USB$?

$A$ carrier wave of peak voltage $16 \text{ V}$ is used to transmit a signal. If the modulation index is $75 \%$, the peak voltage of the modulating signal is (in $\text{ V}$)

Statement-$1$: Sky wave signals are used for long-distance radio communication.
Statement-$2$: These signals are generally less stable than ground wave signals.

$A$ carrier is simultaneously modulated by two sine waves with modulation indices of $0.3$ and $0.4$; then the total modulation index is

The height of a $TV$ transmitter antenna is $100 \ m$. What is the area covered by the transmitter for broadcasting? $(R = 6.4 \times 10^{6} \ m)$