Visible light consists of electromagnetic waves with wavelengths (in air) in the range 400 - 700 nm. What are the frequencies of visible light?

Answer 1

Since this is not my area of expertise, I searched Google under the key words "visible light frequency" to get these possible sources:

http://www.windows.ucar.edu/tour/link=/physical_science/magnetism/em_visible_light.html&portal=vocals
http://en.wikipedia.org/wiki/Visible_spectrum
http://www.adec.edu/tag/spectrum.html

In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search. Also see http://hanlib.sou.edu/searchtools/.

I hope this helps.

Answer 2

use
velocity=(wavelength)(frequency)
solve for frequency
where velocity is equal to speed of light.