Question

local AM radio station broadcasts at a frequency of 685.9 kHz. Calculate the wavelength at which they are broadcasting. Wavelength

Answer 1

Answer:

λ = 437 m.

Explanation:

• Since a radio wave is a electromagnetic type of wave, it propagates approximately at the same speed of light in vacuum, 3*10⁸ m/s.
• As in any wave, there exist a fixed relationship between the propagation speed, the wavelength and the frequency of the radio wave, as follows:

       $c = \lambda* f (1)$

• Replacing by the values of the speed and the frequency, and solving for the wavelength λ, we get:

       $\lambda = \frac{c}{f} =\frac{3e8 m/s}{685.9e31/s} =437 m (2)$