Technician exam question T3A11
Subelement T3, RADIO WAVE PROPAGATION· Group T3A
Which region of the atmosphere can reflect HF radio waves?
- A.The stratosphere
- B.The troposphere
- C.The ionosphere (correct answer)
- D.The electrosphere
WhyThe ionosphere is the region of the atmosphere that can reflect HF radio waves. The ionosphere, the electrically charged upper layer of the atmosphere formed by solar radiation ionizing gas molecules, is what bends (refracts) HF radio waves back toward Earth, enabling long-distance skywave propagation, answer C. The stratosphere (A) and troposphere (B) are lower, non-ionized atmospheric layers responsible for weather and some VHF ducting effects, not HF skip, and "electrosphere" (D) isn't a real atmospheric layer.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2026-2030 NCVEC Element 2 pool (public domain); the explanation above is original writing, see our methodology.
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