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Electromagnetic Spectrum. MW ovens (2.45 GHz): = 12.2 cm. Remote controls = 980 nm. KBCO (97.3 MHz): = 3.08 m KVOD (88.1 MHz): l = 3.33 m. Solar Spectrum. wavelength in Å. Joseph von Fraunhofer, 1814. Radiation from hot objects. Emission Spectra. Emission spectrum of Hydrogen.
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Electromagnetic Spectrum • MW ovens (2.45 GHz): • = 12.2 cm • Remote controls • = 980 nm • KBCO (97.3 MHz): • = 3.08 m • KVOD (88.1 MHz): • l = 3.33 m
Solar Spectrum wavelength in Å Joseph von Fraunhofer, 1814
Emission Spectra Emission spectrum of Hydrogen
Emission Spectra Emission spectrum of Hydrogen Emission spectrum of Iron
Kirchhoff’s Three Laws of Spectroscopy: • Light from a hot solid object has a continuous spectrum with no dark lines • The same light, passed through a cool gas has the same spectrum, but with certain wavelengths missing dark lines (absorption spectrum) • Light emitted by a hot gas bright lines superimposed on an otherwise black background emission spectrum UV IR