Question

What is the ratio of critical frequency for reflection of radiowaves from $E , F _{1}$ and $F _{2}$ layers in ionosphere of earth's atmosphere having electron density $2 \times 10^{11}$, $5 \times 10^{11}$ and $8 \times 10^{11} m ^{-3}$ respectively?

• A. 6 : 12 : 9 : 33 : 10 : 11
• B. 1.41 : 2.13 : 3.18
• C. 1.41 : 2.24 : 2.83
• D. None of these

Answer 1

Answer: (C)

We know that $V_{c}=(\operatorname{Nmax})^{1 / 2}$
$\therefore y_{c} \propto(\operatorname{Nmax})^{1 / 2}$
$V_{ cE }: V _{ cF 1}: V _{ cF 2}=\left(2 \times 10^{11}\right)^{1 / 2}:\left(5 \times 10^{11}\right)^{1 / 2}:\left(8 \times 10^{11}\right)^{12}$
$=1.41: 2.24: 2.83$