# Question #680fd

##### 1 Answer

Apr 18, 2017

Let's break this down.

You are given the wavelength (

We know that frequency of an electromagnetic wave is just the reciprocal of time taken by that wave to complete one cycle, i.e. the time taken to cover one wavelength.

Let velocity of the wave be

Replacing

We know that the speed of an electromagnetic wave is the well known constant

Using appropriate units, we get: