Calculate the phase velocity of electromagnetic wavehaving electron density and frequency for D layer, N=400 electron/cc, v=300 kHz

Options

A. `3xx10^(8)m//s`
B. `3-75xx10^(8) m//s`
C. `6.8xx10^(8)m//s`
D. `1.1xx10^(9)m//s`

Explanation

`mu=sqrt(1-(81.45N)/(v^(2))=sqrt(1-(81.45xx400xx10^(6))/((300xx10^(3))^(2))`
`=0.80`
Phase velocity, `v=(c)/(mu)= (3xx10^(8))/(0.8)=3.75xx10^(8)m//s`