Given that,
Frequency of radio wave is from f = 10⁵ Hz and f' = 10³ Hz
We need to find the wavelength of radio wave. The speed of a wave is given by formula as follows :
If f = 10⁵ Hz
[tex]v=f\lambda\\\\\lambda=\dfrac{c}{f}\\\\\lambda=\dfrac{3\times 10^8}{10^5}\\\\\lambda=3000\ m[/tex]
or
[tex]\lambda=3\ km[/tex]
If f' = 10³ Hz
[tex]v=f\lambda\\\\\lambda'=\dfrac{c}{f'}\\\\\lambda'=\dfrac{3\times 10^8}{10^3}\\\\\lambda'=300000\ m[/tex]
or
[tex]\lambda'=300\ km[/tex]
So, the wavelength of this radio wave on the order of kilometres.