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Question
A TV transmission tower antenna is at a height of 20 m. How much service area can it cover if the receiving antenna is (i) at ground level, (ii) at a height of 25 m? Calculate the percentage increase in area covered in case (ii) relative to case (i).
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Solution
(i) Range = `sqrt(2 xx 6.4 xx 10^6 xx 20)` = 16 km
Area covered = 803.84 km2
(ii) Range = `sqrt(2 xx 6.4 xx 10^6 xx 20) + sqrt(2 xx 6.4 xx 10^6 xx 25)`
= (16 + 17.9) km2
= 33.9 km
Area covered = 3608.52 km2
∴ Percentage increase in area = `((3608.52 - 803.84))/803.84 xx 100`
= 348.9%
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