what is the speed of light?

Answer 1

Light speed is 186,000 miles per second.

In a nanosecond, light travels about a FOOT.

Inside your computer that is running a 1GHz, one nanosecond elapses for each cycle.

So a 3 GHz computer will only allow light to travel 4 inches. Electricity conducts in copper and gold somewhat slower than that, so maybe you have 2 inches of signal travel when your CPU is running at 3GHz. So now you can see the physical limitations of computer speed by simply increasing the clock speed.

That is why the AMD and Intel Core Duo have gone to a 64bit bus. By increasing the width, they gain a next generation of speed. But this will also be at the cost of developing 64 bit software that will also run the OLD FASHIONED 32 bit software. Since this is ALL NEW, you can expect some more Microsoft BUGS.

Motorola would not make this LEAP into the technology for Apple. Since Apple still wallows at less than 5% of the market share; the people at Motorola could not see that it would ever pay off... so new Macs will use Intel Chips.

Good luck and Happy Computing!

Answer 2

the speed of light =3*10^8 m/s

Answer 3

The speed of light. Although light seems to travel across a room the instant a window shade is raised, it actually takes some time to travel any distance. The speed of light in empty space-where atoms do not delay its travel-is 186,282 miles (299,792 kilometers) per second. This speed is said to be invariant because it does not depend on the motion of the light's source. For example, light that is emitted by a rapidly moving flashlight has the same speed as light that is emitted by a stationary flashlight. Scientists do not know why this is true, but the fact is one of the foundations of Einstein's theory of relativity.

From ancient times, people argued about whether the speed of light is limited or infinite. During the early 1600's, the Italian physicist Galileo devised an experiment to measure the speed of light, and so settle the argument. Galileo sent an assistant to a distant hill with instructions that the assistant should open the shutter of a lantern when he saw Galileo on another hill open the shutter of his lantern. Galileo reasoned that because he knew the distance between the hills, he could find the velocity of light by measuring the time between opening his shutter and seeing the light of the second lantern. Galileo's thinking was sound, but the experiment failed. The velocity of light is so great that he could not measure the short time involved.

About 1675, the Danish astronomer Olaus Roemer came upon evidence which proved that light travels at a finite (limited) speed. While working in Paris, Roemer observed that the intervals between the disappearance of some of Jupiter's moons behind the planet varied with the changing distance between Jupiter and Earth. Roemer realized that the finite velocity of light caused these differing intervals. Roemer's observations indicated that light traveled at a speed of 226,000 kilometers per second. This figure was within 25 per cent of the actual velocity.

In 1926, the American physicist Albert A. Michelson made one of the first precise measurements of the velocity of light. He used a rapidly rotating mirror that reflected a beam of light to a distant reflector. The returning beam was then reflected back to the observer by the rotating mirror. Michelson adjusted the speed of the mirror until the mirror turned to the correct angle during the time the light traveled to the reflector and back. The speed of the mirror indicated the velocity of the light. Michelson actually used several mirrors on a drum so that the angle the drum had to turn while the light traveled out and back was small. He measured the speed of light at 299,796 kilometers per second. This measurement had a probable error of less than 4 kilometers per second.

Answer 4

For ease in practical applications, the value 3 * 10 ^ 8 m/s is used as the speed of light.

Answer 5

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

Answer 6

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 any transparent or translucent material medium, like glass or air, it has a lower speed than in a vacuum; the ratio of c to this slower speed 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.

Answer 7

The speed of light in vacuum = 299 792 458 m / s
approx 3*10^8 m/s

or

186282.3971 miles/s ~186000 miles/sec

Answer 8

the speed of light = 299 792 458 m / s

Answer 9

speed of light (′spēd əv ′līt)
(electromagnetism) The speed of propagation of electromagnetic waves in a vacuum, which is a physical constant equal to exactly 299,792.458 kilometers per second. Also known as electromagnetic constant; velocity of light

Answer 10

3*10^8 meters/second is the speed of th light...