as in lighting and such!
2006-10-29 06:13:13 · 9 answers · asked by spanky57 1 in Science & Mathematics ➔ Physics
Quoting wikipedia
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.
2006-10-29 06:15:57 · answer #1 · answered by spongeworthy_us 6 · 0⤊ 0⤋
Everyone talks about a specific number for the speed of light, and that is because it is an upper limit to how fast anything can travel. But, the speed limit is related to the medium in which the light is travelling, related to the permittivity and permeability of the medium. In free space most of the answers are correct at around 3x10^10 cm/sec. In other media the speed is slower. There is an interesting phenomenon when particles come out of a reactor travelling very fast and enter water surrounding the reactor, where the speed of light is slower than they are travelling. The particles slow down and emit what is called Cherenkov radiation.
The speed of light in a piece of raw beef is about 85% of that in free space. In a special material called barium strontium titanate, the speed of light is very, very slow. I think it is less than 10% of the free space value. Very interesting substance.
2006-11-01 20:32:00 · answer #2 · answered by harvs 2 · 0⤊ 0⤋
Speed of light in Vaccum = 3 * 10^8 m/sec
Lightning is faster than thunder. Hence we see the flash first and the clap of thunder later
2006-10-30 01:23:27 · answer #3 · answered by Santhosh S 5 · 0⤊ 0⤋
Light is a type of wave.It travels at a rate os 3oo,ooo,ooom/s.
Sound on the other have travel at only 330m/s.Thats why when there is thounder and lightening we see the light first then after we here the sound because light travels faster than sound.
2006-10-29 14:29:18 · answer #4 · answered by Trina 2 · 0⤊ 0⤋
300000000 m/s is the velocity of light in vaccum.
in other mediums it decreases.
and becomes (1/ refractive index of the medium) times velocity of light in vaccum.
2006-10-31 05:39:57 · answer #5 · answered by go4sambhav 1 · 0⤊ 0⤋
Approximately 186,282.397 miles per second.
2006-10-29 19:31:44 · answer #6 · answered by Anonymous · 0⤊ 0⤋
for prelimnary----
it travells 30,00,00,000 metres every second!
think how fast!
2006-10-29 14:24:03 · answer #7 · answered by catty 4 · 0⤊ 0⤋
300000000m/s
thnx!
2006-10-30 04:06:49 · answer #8 · answered by Anonymous · 0⤊ 0⤋