The $...........$ is the link connecting the transmitter and the receiver.

The sound produced by a tuning fork is a/an .....

The $T.V.$ transmission tower in Delhi has a height of $245 \ m$. The distance up to which the broadcast can be received (taking the radius of the earth to be $6.4 \times 10^6 \ m$) is .......... $km$.

For an amplitude modulated wave,the maximum and minimum amplitudes are found to be $10 \ V$ and $2 \ V$ respectively. Then the modulation index is

The number of amplitude modulated broadcast stations that can be accommodated in a $300\, kHz$ bandwidth for the highest modulating frequency of $15\, kHz$ is:

When the receiving antenna is on the ground,the range of a transmitting antenna of height $980 \ m$ is (Radius of the earth $= 6400 \ km$) (in $km$)