General exam question G3A14
Subelement G3, RADIO WAVE PROPAGATION· Group G3A
How is long distance radio communication usually affected by the charged particles that reach Earth from solar coronal holes?
- A.HF communication is improved
- B.HF communication is disturbed (correct answer)
- C.VHF/UHF ducting is improved
- D.VHF/UHF ducting is disturbed
WhyCharged particles reaching Earth from solar coronal holes usually disturb long-distance HF communication. Charged particles streaming from a coronal hole disturb Earth's ionosphere similarly to a geomagnetic storm, so long-distance HF communication tends to be disturbed, not improved, when they arrive, answer B. They don't improve HF conditions, and coronal-hole particle streams are an HF/ionospheric effect, not specifically a VHF/UHF ducting phenomenon.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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