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प्रश्न
A TV transmission tower has a height of 240 m. Signals broadcast from this tower will be received by LOS communication at a distance of (assume the radius of earth to be 6.4 × 106 m)
- 100 km
- 24 km
- 55 km
- 50 km
पर्याय
a, b and c
b, c and d
c, a and b
a, d and c
उत्तर
b, c and d
Explanation:
Here, h = 240 m
d = ?
R = 6.4 × 106 m
The maximum distance on earth from the transmitter up to which a signal can be received is
d = `sqrt(2Rh)`
= `sqrt(2 xx (6.4 xx 10^6 xx 240))`
= `55.4 xx 10^3` m
= 55.4 km
Therefore, the range of 55.4 km covers the distance 24 km, 55 km and 50 km.
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