Extra exam question E3C06
Subelement E3, RADIO WAVE PROPAGATION· Group E3C
How does the VHF/UHF radio horizon compare to the geographic horizon?
- A.It is approximately 15 percent farther (correct answer)
- B.It is approximately 20 percent nearer
- C.It is approximately 50 percent farther
- D.They are approximately the same
WhyThe VHF/UHF radio horizon extends approximately 15 percent farther than the geographic horizon. Because the atmosphere gradually bends VHF and UHF radio waves downward as they travel, following Earth's curvature slightly more than a straight optical line of sight would, the radio horizon extends about 15 percent farther than the geographic (visual) horizon, answer A. It isn't nearer than the geographic horizon, and the effect is a modest 15 percent extension, not a dramatic 50 percent increase or no difference at all.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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