If a signal of frequency $3 \ kHz$ is to be transmitted via amplitude modulation,which of the following should be chosen as the carrier wave frequency?

$AM$ (Amplitude Modulation) is used for broadcasting because...

Ground waves are polarized in which direction?

The audio signal used to modulate $60 \sin(2\pi \times 10^6 t)$ is $15 \sin(300\pi t)$. The depth of modulation is.......$\%$

If a number of sine waves with modulation indices $n_1, n_2, n_3, \dots$ modulate a carrier wave, then the total modulation index $(n)$ of the wave is:

$A$ telephonic communication service is working at a carrier frequency of $20 GHz$. Only $20 \%$ of it is utilized for transmission. If each channel requires a bandwidth of $5 kHz$,then the number of telephonic channels that can be transmitted simultaneously are