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hechnal
Jun28-08, 12:26 AM
hey,

just wondering, what's the relationship between absorption and emissions spectra (i.e. would they absorb and reflect the same wavelengths or complement wavelengths of radiation?)

thanx,

hechnal

Redbelly98
Jun28-08, 07:50 AM
Light that strikes an object is either:
1. Absorbed
2. Reflected
or
3. Transmitted

These must all add up to 100%:

A + R + T = 100%

For opaque objects, T=0 (no transmission) and the equation simplifies somewhat.

mathman
Jun28-08, 03:52 PM
hey,

just wondering, what's the relationship between absorption and emissions spectra (i.e. would they absorb and reflect the same wavelengths or complement wavelengths of radiation?)

thanx,

hechnal
For a particular substance, they are the same. It depends on the temperature of the medium relative to the light coming through. Hotter leads to emission, colder leads to absorption.