2007-02-08 16:31:13 · 11 answers · asked by ahleks 2 in Science & Mathematics ➔ Mathematics
the speed of light = 299 792 458 m / s
2007-02-08 16:37:52 · answer #1 · answered by mei_77 2 · 1⤊ 0⤋
The speed of light in a vacuum is an important physical constant denoted by the letter c for constant or the Latin word celeritas meaning "swiftness". It is the speed of all electromagnetic radiation in a vacuum, not just visible light.
In metric units, c is exactly 299,792,458 metres per second (1,079,252,848.8 km/h). Note that this speed is a definition, not a measurement. Since the fundamental SI unit of length, the metre, has been defined since October 21, 1983 in terms of the speed of light; one metre is the distance light travels in a vacuum in 1/299,792,458 of a second. Converted to imperial units, the speed of light is approximately 186,282.397 miles per second, or 670,616,629.384 miles per hour, or almost one foot per nanosecond.
Through a transparent or translucent material medium, like glass or air, it may appear to have a different speed than in a vacuum; the ratio of c to the observed phase velocity (which may be both smaller or larger than c) is called the refractive index of the medium. Changes of gravity, however, warp the space the light has to travel through, making it appear to curve around massive objects. This gives rise to the phenomenon of gravitational lensing, in which large assemblies of matter can refract light from far away sources, so as to produce multiple images and similar optical distortions.
2007-02-08 16:39:29 · answer #2 · answered by sushimaven 4 · 0⤊ 0⤋
the speed of light = 299 792 458 m / s
In metric units, c is exactly 299,792,458 metres per second (1,079,252,848.8 km/h). Note that this speed is a definition, not a measurement.
2007-02-08 16:33:41 · answer #3 · answered by Michael Dino C 4 · 0⤊ 0⤋
well it takes 8.0 seconds from the light from the sun to REACH the earth thats fast
2007-02-08 16:34:41 · answer #4 · answered by luigi 2 · 0⤊ 0⤋
Faster than the speed of dark.
or 187,000 miles / sec.
2007-02-08 16:33:31 · answer #5 · answered by Ben Aqui 5 · 0⤊ 0⤋
About 300,000,000 meters per second.
2007-02-08 16:33:48 · answer #6 · answered by extton 5 · 0⤊ 0⤋
186000 miles per second
2007-02-08 16:34:19 · answer #7 · answered by Campo 4 · 0⤊ 0⤋
it has been a while, but if i remember it is:
c = 300,000,000 m/s^2
2007-02-08 16:34:49 · answer #8 · answered by john 2 · 0⤊ 0⤋
186,000 miles per second
2007-02-08 16:55:32 · answer #9 · answered by Anonymous · 0⤊ 0⤋
3.0x10^8 m/s
2007-02-08 16:35:25 · answer #10 · answered by Milton's Fan 3 · 0⤊ 0⤋