Q12 of 805 Page 1

A TV transmission tower antenna is at the height of 20 m. How much range can it cover if the receiving antenna is at the height of 25 m?

Given: -


The height of the transmitting antenna, 20 m.,


The height of the receiving antenna, 25 m.,


Formula: -


The maximum line-of-sight distance dM between the two antennas having heights hT and hR above the earth is given by,


DM = (2 R hT)1/2 + (2 R hR)1/2


where hR is the height of receiving antenna, where hT is the height of the transmitting antenna and R is the radius of the earth (6400 Km approx.).


So, substituting the values, we get,


DM = (2 × 6400000 × 20)1/2 + (2 × 6400000 × 25)1/2


≈33888 m


DM = 33.8 Km


Conclusion:


The Range of the Transmission is, DM = 33.8 Km.


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