Question

Expression for effective radius factor k in terms of radius of curvature rc and radius of earth re?

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

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

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

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

This question was addressed to me during an interview.

This intriguing question comes from Space Wave Propagation in portion Space Wave Propagation of Antennas

Answer 1

Correct choice is (b) \(k=\frac{1}{1-\frac{r_e}{r_c}} \)

To explain I would say: 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

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