A Quick Introduction to LIGHT
Light: What IS it?
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It's made up of oscillating electric and magnetic fields.
This is why we refer to it as electromagnetic radiation
It's really an amazing thing!
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Travels without any medium
Travels at a finite speed, but very fast (``c'' = 300,000 km/s)
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Moon to earth in ONE SECOND!
Earth to Sun ?
Outer Solar System ?
| Light is a wave. It has CRESTS and TROUGHS. The distance from one crest to the next (or one trough to the next) is called the WAVELENGTH: |
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Another way to look at light is to count the number of crests that pass by.
This gives you the frequency of the light:
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You can identify the light as having a particular wavelength OR frequency, and these are related because the SPEED of light, `c', is a constant. They are related in this way:
WHERE:
