Basic Qualification · B-007 Radio wave propagation · B-007-005-005
What influences all radiocommunication beyond ground wave or line-of-sight ranges?
- A The F1 region of the ionosphere
- B Lunar tidal effects
- C Solar radiation
- D The F2 region of the ionosphere
Correct answer: C — Solar radiation. From the official ISED question bank, verified word for word.
Why
Solar radiation, the energy emitted by the Sun, is the driving force behind the ionosphere, the layer of charged particles that bends radio waves back to Earth for long-distance communication. The full explanation — and one for every question — is in Pro.
Practise this section
How signals travel: the ionosphere and its layers, skip, ground wave, sporadic E, and which bands work when.