Question

A T.V. tower at a height of 10 m is in a region of average population density $100\pi /k{m}^2$. The number of people that can receive the transmission is nearly

• A. $1,28,000$
• B. $64,000$
• C. $2,56,000$
• D. $32,000$

Answer 1

The correct option is A $1,28,000$

$d_{max}=\sqrt{2R{H}_T}=\sqrt{2\times 6400\times .01}=8\sqrt{2}kmA=\pi {d_{max}}^2=\pi \times ({8\sqrt{2})}^2=128\pi {km}^2$

Number of people the signals can reach to is: $N=100\pi \times 128\pi =128,000$