The radio waves travel with the speed of light in a vacuum. The time taken by the radio wave to reach the station is [tex]1.33 \times 10^{-4} \;\rm s[/tex].
Radio waves are a type of electromagnetic wave whose wavelength falls in the electromagnetic spectrum. The radio waves have the longest wavelengths among electromagnetic waves.
Given that the distance d of the station is 40 km. The speed s of radio waves is 3 X 10^8 m/s.
The times taken by the radio wave to reach the station are calculated as given below.
[tex]s = \dfrac {d}{t}[/tex]
[tex]3 \times 10^8 = \dfrac{40\times 1000}{t}[/tex]
[tex]t = \dfrac {40\times 1000}{3\times 10^8}[/tex]
[tex]t = 1.33 \times 10^{-4} \;\rm s[/tex]
Hence we can conclude that the time taken by the radio wave to reach the station is [tex]1.33 \times 10^{-4} \;\rm s[/tex].
To know more about the radio waves, follow the link given below.
https://brainly.com/question/9279417.
