The electron density of E, F_1, and F_2 layer | vedclass

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(C) The critical frequency $f_c$ for the reflection of radio waves from an ionospheric layer is given by the relation $f_c = 9 \sqrt{N_{max}}$,where $

Vedclass · Accepted Answer

$2 : 3 : 4$

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(C) The critical frequency $f_c$ for the reflection of radio waves from an ionospheric layer is given by the relation $f_c = 9 \sqrt{N_{max}}$,where $N_{max}$ is the maximum electron density.This implies that $f_c \propto \sqrt{N}$.Given the electron densities $N_E = 4 	imes 10^{11} \, m^{-3}$,$N_{F_1} = 9 	imes 10^{11} \, m^{-3}$,and $N_{F_2} = 16 	imes 10^{11} \, m^{-3}$.The ratio of critical frequencies is:$(f_c)_E : (f_c)_{F_1} : (f_c)_{F_2} = \sqrt{4 	imes 10^{11}} : \sqrt{9 	imes 10^{11}} : \sqrt{16 	imes 10^{11}}$$= \sqrt{4} : \sqrt{9} : \sqrt{16}$$= 2 : 3 : 4$.

The electron density of $E, F_1,$ and $F_2$ layers of the ionosphere is $4 \times 10^{11} \, m^{-3}, 9 \times 10^{11} \, m^{-3},$ and $16 \times 10^{11} \, m^{-3}$ respectively. What is the ratio of the critical frequencies for the reflection of radio waves?

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