Question

Beyond which frequency, the ionosphere bends any incident electromagnetic radiation but do not reflect it back towards the earth?

• A. 50MHz
• B. 40MHz
• C. 30MHz
• D. 20MHz

Answer 1

Answer: (B)

40MHz

Answer 2

The ionosphere can reflect electromagnetic waves of frequency less than $40\, MHz$ but do not reflect electromagnetic waves of frequency more than $40 \,MHz$.