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What should be the height of transmitting antenna and population covered if television telecast is to cover a radius of 150 km? The average population density in tower is 2000/km and the value of Re = 6.5 × 10⁶ m.

1. Height = 1731 m Population Covered = 1413 × 10⁵
2. Height = 1241 m Population Covered = 7 × 10⁵
3. Height = 1600 m Population Covered = 2 × 10⁵
4. Height = 1800 m Population Covered = 1413 × 10⁸

Correct answer: Height = 1731 m Population Covered = 1413 × 10⁵

Solution

Coverage radius d = sqrt(2*Re*h) -> h = d^2/(2*Re) = (150000)^2/(2*6.5e6) = 1731 m. Population = 2000 * pi * d^2 = 2000 * pi * (150)^2 = 1413 x 10^5.

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