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The electron dencity of E, F(1),F(2) lay...

The electron dencity of `E, F_(1),F_(2)` layers of ionosphere is `2xx10^(11), 5xx10^(11)` and `8xx10^(11) m^(-3)` respectively. Wht is the ratio of critical frequency for reflection of radiowaves?

A

`2:4:3`

B

`4:3:2`

C

`2:3:4`

D

`3:2:4`

Text Solution

Verified by Experts

The correct Answer is:
c
`f_(c) prop(N)^(1//2)implies(f_(c))_(E) :(f_(c))_(F_(1)) :(f_(c))_(F2)`
`(2xx10^(11))^(1//2) :(5xx10^(11))^(1//2) :(8xx10^(11))^(1//2)=2:3:4`
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