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Two identical antennas mounted on identical towers are separated from each other by a distance of 45 km. What should be the nearby minimum height of receiving antenna to receive the signals in line of sight ? (Assume radius of earth is 6400 km)

1. 19.77 m
2. 39.55 m
3. 79.1 m
4. 158.2 m

Correct answer: 39.55 m

Solution

The minimum height of the receiving antenna is determined by the line of sight distance, which depends on the curvature of the Earth. Using the formula for line of sight, the height required for a 45 km distance results in approximately 39.55 m, ensuring that the antenna can receive signals without obstruction.

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