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What should be the minimum electron dens...

What should be the minimum electron density in the ionosphere, for the sky wave propagation of a 9 MHz signal?

A

`1.5xx10^12//m^3`

B

`10^12//m^3`

C

`0.5xx10^12//m^3`

D

`0.8xx10^12//m^3`

Text Solution

Verified by Experts

The correct Answer is:
B
For the sky wave propagation of the given signal , the critical frequency is given by `v_c=9 (N_"max")^(1//2)`
`therefore v_c^2=81 (N_"max")`
`therefore N_"max"=v_c^2/81=(9xx10^6xx9xx10^6)/(81)=10^12`
`therefore N_"max"=10^(12) m^3`
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