Difference between revisions of "Speed of light"
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==Definition== | ==Definition== | ||
| − | The '''Speed of Light''' (or '''''c''''') is the speed at which a photon (an "energy packet" of electromagnetic radiation) travels in a vacuum. | + | The '''Speed of Light''' (or '''''c''''') is the speed at which a [[photon]] (an "energy packet" of electromagnetic [[radiation]]) travels in a [[vacuum]]. |
===Values=== | ===Values=== | ||
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:<math>c = 1.9 \times 10^{5} \mathrm{mis^{-1}}</math> | :<math>c = 1.9 \times 10^{5} \mathrm{mis^{-1}}</math> | ||
| + | ==Consequences of the Speed of Light== | ||
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| + | ===Communication=== | ||
| + | [[Humans]] have discovered methods to communicate over great distances using electromagnetic (EM) radiation, such as radio waves and lasers. On Earth, distances are short enough that these methods seem instantaneous. On [[Mars]] and other parts of the [[solar system]], communication with Earth involves a time delay, based on the time it takes the EM radiation to travel. The delay between Earth and Mars varies from 3 minutes to 22 minutes. | ||
==See also== | ==See also== | ||
Revision as of 14:54, 26 December 2008
Definition
The Speed of Light (or c) is the speed at which a photon (an "energy packet" of electromagnetic radiation) travels in a vacuum.
Values
The exact measurement for the speed of light is 299,792,458 meters per second, in the following values, the speed of light will use values based on the rounded 300,000,000 m/s.
Meters per second:
Kilometers per second:
Miles per second:
Consequences of the Speed of Light
Communication
Humans have discovered methods to communicate over great distances using electromagnetic (EM) radiation, such as radio waves and lasers. On Earth, distances are short enough that these methods seem instantaneous. On Mars and other parts of the solar system, communication with Earth involves a time delay, based on the time it takes the EM radiation to travel. The delay between Earth and Mars varies from 3 minutes to 22 minutes.
