It is now a universal constant which is exactly 299792458 ms. Speed of light calculator for the distance per time or time per distance. Formula of the speed of light in the air.
Now apply Snells law to the ratio of sines to derive the formula for the refracted rays direction vector.
299792458 meters per second 186282 miles per seconda speed. Whenever light is in a vacuum its speed has that exact value no matter who measures it. C the speed of light 300000 kms or 30 x 10 8 ms the wavelength of light usually measured in meters or Angstroems 1 A 10-10 m f the frequency at which light waves pass by measured in units of per seconds 1s. According to the formula for the speed of light v c n we obtain that the speed in this medium is approximately equal to 200 000 km s.