Which of the following statements is NOT corr | vedclass

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(C) The critical frequency $(f_c)$ is defined as the highest frequency that is reflected back by the ionosphere when incident vertically. Waves with f

Vedclass · Accepted Answer

Electromagnetic waves of frequencies higher than about $30 \, MHz$ cannot penetrate the ionosphere.

Vedclass · Answer

(C) The critical frequency $(f_c)$ is defined as the highest frequency that is reflected back by the ionosphere when incident vertically. Waves with frequencies higher than the critical frequency penetrate the ionosphere and are not reflected. Statement $C$ claims that waves with frequencies higher than $30 \, MHz$ cannot penetrate the ionosphere, which is incorrect because frequencies above the critical frequency (typically $3-30 \, MHz$ for the ionosphere) easily penetrate it.

Which of the following statements is $NOT$ correct?

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