Q 12-08-110JEE MainJEE Main 2023 (8 Apr, Shift 1)Easy
A TV transmitting antenna is $98$ m high and the receiving antenna is at the ground level. If the radius of the earth is $6400$ km, the surface area covered by the transmitting antenna is approximately
Answer: (B) $3942\ \text{km}^2$
Range $d=\sqrt{2Rh}$, so the area is $\pi d^2=2\pi Rh=2\times3.14\times6400\times0.098\approx3940\ \text{km}^2$.
Solution by Sreeraj P, M.Sc Physics