MCQ
Beyond which frequency, the ionosphere bends any incident electromagnetic radiation but do not reflect it back towards the earth?
  • A
    30 MHz
  • B
    50 MHz
  • C
    20 MHz
  • D
    40 MHz

Answer

D. 40 MHz
Explanation:
The ionosphere can reflect electromagnetic waves of frequency less than 40 MHz but not of frequency more than 40 MHz .

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