Basic Qualification · B-007 Radio wave propagation · B-007-005-009
Average duration of a solar cycle is:
- A 3 years
- B 6 years
- C 1 year
- D 11 years
Correct answer: D — 11 years. From the official ISED question bank, verified word for word.
Why
The Sun follows a natural rhythm where its magnetic activity, including sunspots and solar flares, rises and falls over a period of roughly 11 years. 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.