If sky wave with a frequency of 60 MHz is incident on D- region at an angle of `30^@`, then find the angle of refractive.

Options

A. `15^(@)`
B. `30^(@)`
C. `60^(@)`
D. `45^(@)`

Explanation

`v=50 MHz=50xx10^(6)Hz, i=30^(@)`,
`N=10^(9)m^(-3)`
`mu=sqrt(1-(81.45N)/(v^(2)))=sqrt(1-(81.45xx10^(9))/((50xx10^(6))))=1`
`mu=(sin i)/(sin r)` or `1=(sin i)/(sin r)` or `sin i=sin r` or `r=i=30^(@)`