Question

What is the effective radius factor when radius of curvature is 4 times the radius of earth?

(a) 4

(b) 4/3

(c) 3

(d) 3/4

I have been asked this question in my homework.

The origin of the question is Space Wave Propagation in chapter Space Wave Propagation of Antennas

Answer 1

The correct answer is (b) 4/3

Easy explanation: Effective radius factor k in terms of radius of curvature rc  and radius of earth re is

\(k=\frac{1}{1-\frac{r_e}{r_c}} \)

The radius of curvature is four times the radius of earth. rc=4re

⇨ K=1/(1-(1/4)) =4/3

The effective radius factor of earth is 4/3 times actual radius of earth.