$A$ $TV$ tower has a height of $5 \, m$ in a region of population density $\frac{1000}{\pi}$ per square kilometre. The number of people that can receive the transmission is nearly, (in thousands)

What is a transducer?

An antenna is placed in a dielectric medium of dielectric constant $6.25$. If the maximum size of the antenna is $5.0 \, mm$,what is the minimum frequency of the signal it can radiate in $GHz$? (Given $\mu_{r} = 1$ for the dielectric medium)

This question has Statement-$1$ and Statement-$2$. Of the four choices given after the statements,choose the one that best describes the two statements.
Statement-$1$: Sky wave signals are used for long-distance radio communication. These signals are,in general,less stable than ground wave signals.
Statement-$2$: The state of the ionosphere varies from hour to hour,day to day,and season to season.

If the maximum and minimum voltage of an $AM$ wave are $V_{max}$ and $V_{min}$,then the modulation index is given by:

$A$ $100\,m$ long antenna is mounted on a $500\,m$ tall building. The complex can become a transmission tower for waves with $\lambda$ (approx) ........ $m$.