Q. The area of the region covered by the TV broadcast by a TV tower of $100\ m$ height is (radius of the earth $= 6.4 \times 10^{6}\ m$)
A) $12.8\pi \times 10^{8}\ km^{2}$
B) $1.28\pi \times 10^{3}\ km^{2}$
C) $0.64\pi \times 10^{3}\ km^{2}$
D) $1.28\pi \times 10^{3}\ km^{2}$
Explanation
(b) Area covered by T.V. signals
$A = 2\pi hR = 2 \times 3.14 \times 100 \times 6.4 \times 10^{6} = 128\pi \times 10^{8}$
$\Rightarrow A = 1.28\pi \times 10^{3}\ km^{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.