Basic Qualification · B-007 Radio wave propagation · B-007-002-006
Quand l'ionosphère est-elle ionisée au maximum?
- AAu milieu de la journée
- BAvant le lever du soleil
- CAu milieu de la nuit
- DAu crépuscule
Correct answer: A — Au milieu de la journée. Question tirée de la banque officielle d'ISDE.
Why
The ionosphere is most ionized at Midday because the Sun's ultraviolet radiation is strongest when it is directly overhead, stripping electrons from atoms in the upper atmosphere. 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