Find out the maximum electron density of the ionosphere if the maximum frequency of the radiowaves which returns to the earth after reflecting from th
Find out the maximum electron density of the ionosphere if the maximum frequency of the radiowaves which returns to the earth after reflecting from the ionosphere is 18 MHz.
A. `8m^(-3)`
B. `6m^(-3)`
C. `4 m^(-8)`
D. `2 m^(-3)`
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Correct Answer - C
Given , critical frequency ` (f_(c))=18MHz ` maximum electron density `(N_("max "))=?`
As we know that ` f_(c)=9(N_("max")=?`
`implies 18=9(N_("max"))^(1//2)`
` or N_("max")=[(18)/(9)]^(2) or N_("max")=4m^(-3)`
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