Basic Qualification · B-007 Radio wave propagation · B-007-002-005
Which region of the ionosphere separates into two sub-regions in the daytime?
- A The D region
- B The G region
- C The F region
- D The E region
Correct answer: C — The F region. From the official ISED question bank, verified word for word.
Why
The F region splits into two distinct layers, called F1 and F2, only when the sun is up, because solar radiation ionizes the upper atmosphere differently during daylight hours. 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.