The Best Actual Value Of The Speed Of Light References. Web the average value found for the speed of light is. Web the speed of light in vacuum, commonly denoted c, is a universal physical constant that is exactly equal to 299,792,458 metres per second (approximately 300,000 kilometres per second;
299,792,458 meters per second (186,282 miles per second)—a. For a further discussion of the ways in which the speed of light has been measured, see: Roemer’s measurement was still wide of the actual value, but it provided a.
