Question

Calculate the wavelength of each of the following frequencies of electromagnetic radiation

A) 104.8 MHz (typical frequency for FM radio broadcasting)

B)1100 kHz (typical frequency for AM radio broadcasting)

C) 835.6 MHz (common frequency used for cell phone communication)

Answer 1

(A) We know that all electromagnetic radiation travels with the speed of light

We know that frequency,v = c / λ

Where

c = speed of light = 3x 10⁸ m/s

λ = wave length = ?

v = frequency = 104.8 MHz *10⁶ Hz/MHz = 104.8*10⁶ Hz OR s^-1

Plug the values we get λ = c / v

                                    = (3x 10⁸ m/s) / (104.8*10⁶ s^-1)

                                   = 2.862 m

(B) Given

c = speed of light = 3x 10⁸ m/s

λ = wave length = ?

v = frequency = 1100 kHz *10³ Hz/MHz = 1100*10³ Hz OR s^-1

Plug the values we get λ = c / v

                                    = (3x 10⁸ m/s) / (1100*10³ s^-1)

                                   = 272.7 m

(B) Given

c = speed of light = 3x 10⁸ m/s

λ = wave length = ?

v = frequency = 835.6 MHz *10⁶ Hz/MHz = 835.6*10³ Hz OR s^-1

Plug the values we get λ = c / v

                                    = (3x 10⁸ m/s) / ( 835.6*10³ s^-1)

                                   = 359.0m