Electromagnetic spectrum: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Alex MacDonald
mNo edit summary
imported>Alex MacDonald
mNo edit summary
Line 7: Line 7:


:<math>\lambda = \frac{c}{f}  \,\!</math> ,  
:<math>\lambda = \frac{c}{f}  \,\!</math> ,  
<math>E=hf \,\!</math> ,
:<math>E=hf \,\!</math> ,


where c = 299,792,458 m/s (the [[speed of light]]) and h = 6.626 x 10<sup>-34</sup> Js ([[Planck's constant]])
where c = 299,792,458 m/s (the [[speed of light]]) and h = 6.626 x 10<sup>-34</sup> Js ([[Planck's constant]])

Revision as of 11:49, 12 August 2007

The Electromagnetic Spectrum is the name given to the range of Electromagnetic radiation covering all frequencies and wavelengths. It includes radio and TV transmission, Microwaves, Infrared, visible light, Ultraviolet, X-rays, and Gamma rays.


Electromagnetic radiation

All electromagnetic radiation can be described in terms of its Energy (E), frequency (f) or wavelength (). These properties are all related by the following equations:
,
,

where c = 299,792,458 m/s (the speed of light) and h = 6.626 x 10-34 Js (Planck's constant)

As well as the wavelike properties of EM radiation several effects particularly of the emission and absorption of light behave like particles. That is, the energy carried by light waves is packaged in discrete bundles called photons or quanta. This wave-particle duality is described in quantum electrodynamics, a theory which began to be developed around 1930.


References