Basic Qualification · B-007 Radio wave propagation · B-007-002-005
Which region of the ionosphere separates into two sub-regions in the daytime?
- AThe D region
- BThe G region
- CThe F region
- DThe 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
Radio wave propagation is section B-007 of the Basic exam: How signals travel: the ionosphere and its layers, skip, ground wave, sporadic E, and which bands work when.
Drill B-007 — free, no account