Difference between revisions of "Beer"

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(Created page with " == 1. The classical law and its history == When electromagnetic radiation, such as ultraviolet or visible light, passes through a transparent medium that contains an ab...")
 
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When electromagnetic radiation, such as ultraviolet or visible light, passes through a transparent medium that contains an absorber of that illumination, the radiation’s intensity diminishes steadily with passage through the medium.  Commonly the radiation is in the form of a collimated beam that impinges perpendicularly on a slab of width L of the medium, as suggested diagrammatically in Figure 1.One may conjecture that, at any illuminated plane x within the medium, the decrease in the intensity I of the radiation with distance would be proportional to the uniform concentration c of the absorber and to the local intensity of the light at that point; that is
 
When electromagnetic radiation, such as ultraviolet or visible light, passes through a transparent medium that contains an absorber of that illumination, the radiation’s intensity diminishes steadily with passage through the medium.  Commonly the radiation is in the form of a collimated beam that impinges perpendicularly on a slab of width L of the medium, as suggested diagrammatically in Figure 1.One may conjecture that, at any illuminated plane x within the medium, the decrease in the intensity I of the radiation with distance would be proportional to the uniform concentration c of the absorber and to the local intensity of the light at that point; that is
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<math>
 
<math>
 
\frac{\mathrm d}{\mathrm d x} ( I(x) )=-\alpha cI(x) (1)
 
\frac{\mathrm d}{\mathrm d x} ( I(x) )=-\alpha cI(x) (1)
 
</math>
 
</math>

Revision as of 22:10, 3 February 2017



1. The classical law and its history

When electromagnetic radiation, such as ultraviolet or visible light, passes through a transparent medium that contains an absorber of that illumination, the radiation’s intensity diminishes steadily with passage through the medium. Commonly the radiation is in the form of a collimated beam that impinges perpendicularly on a slab of width L of the medium, as suggested diagrammatically in Figure 1.One may conjecture that, at any illuminated plane x within the medium, the decrease in the intensity I of the radiation with distance would be proportional to the uniform concentration c of the absorber and to the local intensity of the light at that point; that is

[math] \frac{\mathrm d}{\mathrm d x} ( I(x) )=-\alpha cI(x) (1) [/math]