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The radio horizon of a transmitting antenna of height 39.2 m is (Radius of the earth = 6400 km)
The radio horizon of a transmitting antenna of height 39.2 m is (Radius of the earth = 6400 km)
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The formula for the maximum line-of-sight distance between two antennas of heights \(h_T\) and \(h_R\) is \(d_{max} = \sqrt{2Rh_T} + \sqrt{2Rh_R}\). The radio horizon is just the case for one antenna (\(h_R=0\)). A useful approximation for calculations in km is \(d(\text{km}) \approx 3.57\sqrt{h(\text{m})}\). Here, \(3.57\sqrt{39.2} \approx 3.57 \times 6.26 \approx 22.35\) km.
Updated On: Mar 30, 2026
- 44.8 km
- 19.6 km
- 22.4 km
- 78.4 km
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The Correct Option is C
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