Question

A communications satellite transmits a radio wave at a frequency of 9.4 x 10^9 Hz. What is the signal’s wavelength? Assume the wave travels in a vacuum. Show your work.

Answer 1

To calculate this we will use the light equation:

`c=`λ
`*f`

We have Frequency
`f=9.4* 10^(9)Hz`.
We know that speed of light in vacuum is
`c =3.8* 10^(8) m/s`.
Since a unit of speed of light is m/s, we can change the unit of frequency Hz to 1/s, since Hz means cycles per second (f=1/T).

So:

`f=9.4* 10^(9)1/s`

`c =3.8* 10^(8) m/s`


`c=`λ
`*f`
⇒ λ
`= (c)/(f)`
⇒ λ
`= (3.8* 10^(8))/(9.4* 10^(9))`
⇒ λ
`=0.04 m`