Question

Radio waves travel at the speed of light: 3 × 105 km/s. what is the wavelength of radio waves received at 107.7 mhz on your fm radio dial? answer in units of m.

Answer 1

The speed of light is:

`c=3 \cdot 10^5 km/s = 3 \cdot 10^8 m/s`
while the frequency of the radio waves is

`f=107.7 MHz = 107.7 \cdot 10^6 Hz`

We can find the corresponding wavelength by using the relationship

`\lambda= (c)/(f)`
where

`\lambda` is the wavelength
c is the speed of light
f is the frequency

By susbstituting the numbers, we find

`\lambda= (3 \cdot 10^8 m/s)/(107.7 \cdot 10^6 Hz)=2.79 m`