O n t h e T r a c k o f M o d e r n P h y s i c s
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Transcript of O n t h e T r a c k o f M o d e r n P h y s i c s
O n t h e T r a c k o f M o d e r n P h y s i c s
All difficult words come from Greek. All, but “spectrum”. First used by Cicerone, in Italian means spettro (=ghost), simulacro (= figure or sculpture).Spectroscopy deals with images: a colourful rainbow, a sunset or just the cloudy sky.
In other words: spectrum is a ghost and Spectroscopy - a science on ghosts.
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3CO
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C2H
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cps
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Three upper sky photos are by Carmen Busko, Sao Paolo, Brazil, thanks!http://www.trekearth.com/gallery/South_America/Brazil/photo89543.htmRemaining photos are by GK.
Spectrum is an image, something produced bythe object, like the reflected or emitted light.
Then You need an analyser, to show single components. This can be a prism, a diffraction grate, but also a snow crystal or a CD-cover.
Separated colours, like in a CD form a spectrum.CD-cover “produces” colors, but usually reflecting polarized light, i.e. from blue sky. Unless, the poly-mer is strongly oriented, like here.
Colors in CD-cover are complemen-tary, obtained by subtraction of red, blue or green from white.
Reflection in azzure on borders of the gold-doped, red ash-tray come from Mie scattering, like in the sky.
In the left image no dark blue is present, in the right image no yellow buta lot of red. One is of so-called energetic lamp, one of the morning sky.Can You guess which is which?
Reflection from snow does notproduce colors, but reflectioninside ice crystals does.
Separating colors can be done by refraction, like here, diffraction, like to the right, or scattering.
Look carefully or snap shots:spectra are everywhere. This is Red See.
So, separating features of an object is to make a spectrum. This can be the mass of positive ions in strawberries smell, the energy of photons from an annihilating antimatter, faint hints in the energy dependence for muon production or infrared absorption by silicon.
All these, we call spectra. And all are so beautiful for scientists, as a purple morning sky. Hoping, also for You!
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N2 375.5
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Look! how blue can be different!
And then, also red is different!
Carmem A. BuskoCarmem A. Busko Carmem A. Busko
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