Physics Electromagnetic Waves Electromagnetic Waves Class 12th Physics

A TV transmission tower antenna is at a height of 20m. Suppose that the receiving antenna is at
(i) ground level
(ii) a height of 5m
The increase in the antenna range in case (ii) relative to case (i) is n %.
The value of n, to the nearest integer, is...................

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Answered by

Vishal Baghel | Contributor-Level 10

5 months ago

d_lm = Distance covered by transmitting antenna + Distance covered by receiving antenna

⇒ d_lm = √ (2Rh_transmitting) + √ (2Rh_receiving)
⇒ d_lm = √ (2 * 64 * 10? * 20) + √ (2 * 64 * 10? * 5) = 16000 + 8000 = 24000m

When h_receiving = 0 then
d_2m = √ (2 * 64 * 10? * 20) = 16000m

% increment = (8000/16000

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