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What should be the ratio of the critica...

What should be the ratio of the critical frequencies for reflection or radiowaves from E and `F_1` layers of the ionosphere. If their electrons densities are `2xx10^11//m^3` and `3xx10^11//m^3` respectively ?

A

`sqrt(1/2)`

B

`sqrt(2/3)`

C

`sqrt(3/2)`

D

`sqrt(2/5)`

Text Solution

Verified by Experts

The correct Answer is:
B
Critical Frequency `v_c=9 (N_"max")^(1//2)`
`therefore v_c prop (N_"max")^(1//2)`
`therefore v_E/v_(F_1) =((2xx10^11)^(1//2))/((3xx10^11)^(1//2)) = (2/3)^(1//2) = sqrt2/3`
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