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 Spanish - Chinese The Optics Book - Scattering&Spectrum Written by:Karen
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Related Articles:

Dispersion Prizm Applet
Dispersion Slab Applet
Electromagnetic spectrum

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In this section:

The Optics Book

Spectrum
Scattering
Green water
Fog Lights
8. Color
9. Interferences & difraction
10. Polarization
11. Quantic Optics

# Electromagnetic Spectrum

The electromagnetic spectrum refers to a "map" of the different types of radiant energy and their correlating wavelengths. There are usually 6 subdivisions (Radiowaves, infrared, visible, ultraviolet, x rays, and gamma rays) of the electromagnetic spectrum.

 Electromagnetic Spectrum Click for Full Size Picture Credits: César Salazar

As can be seen, the visible part of the spectrum is actually very small in relation to the other types of energy. From left to right, the spectrum is showing an increase in energy. This increase in energy correlates to the increase in frequency. Frequency holds an inverse relation with wavelength.

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Using the equation, v = lf, where v = speed (in this case of Light), l = wavelength, and f = frequency, we can see this inverse relationship. The proper unit for wavelength is meter (m), and for frequency is Hertz (Hz). The speed of Light, represented by v, is a constant, 3 x10^8 m/s. We can also calculate the frequency if the wavelength is given, and the wavelength if the frequency is given.