MCQ
Beyond which frequency, the ionosphere bands any incident electromagnetic radiation but do not reflect it back towards the earth?
- A$50MHz$
- ✓$40MHz$
- C$30MHz$
- D$20MHz$
✓
Answer
Correct option: B.
$40MHz$
The ionosphere can reflect electromagnetic waves of frequency less than $40MHz$ but not of frequency more than $40MHz.$
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