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Properties of light – A tool in Energy and Environmental Physics. F. Sigernes A trial lecture @ NTNU. A-M Ampère 1775-1836 . M. Faraday 1791-1867. OERSTED, H. C. 1777-1851 . C. F. Gauss 1777-1855 . J. C. Maxwell 1831-1879. H. R. Hertz 1857 - 1894. M. Planck 1858 - 1947 .
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Properties of light – A tool in Energy and Environmental Physics F. Sigernes A trial lecture @ NTNU
A-M Ampère 1775-1836 M. Faraday 1791-1867 OERSTED, H. C. 1777-1851 C. F. Gauss 1777-1855 J. C. Maxwell 1831-1879 H. R. Hertz 1857 - 1894 M. Planck 1858 - 1947 • Einstein • 1879 - 1955 N. Bohr, 1885-1962 Images are taken from search engine Google Images
A plane polarized sinusoidal wave!
Nordkvist (2006) Intensity = Lifetime x # atoms energized
BASIC PROPERTIES OF LIGHT • Light is electromagnetic waves – radiation • It travels through empty space • The speed is constant as a function of wavelength • It is polarized depending on direction or rotation of E • Light are emitted or absorbed in discrete chunks of energy • These packets of energy – photons - have energy E=hv • Photons are released as a response to jumps in atomic / molecular • energy levels (from Bohr’s model of the atom) • 8) Light is both a particle (photon) and a wave – depends how we observe it. • 9) Intensity is directly related to number of photons emitted from an object. • 10) Objects emits light in form of continuous or discrete spectra – • depending mainly on density and temperature. • 11) Light has wavelike behavior: it reflects, refracts, diffracts and interfere...
“Spectroscopy – is the tool to study the properties of objects.” Basics of a hyperspectral imager – a camera that that images as a function of wavelength!
Basics of an airborne hyperspectral imager- bush broom (Zsolt, 2006)
REFERENCES Douglas C. Giancoli, Physics for Scientists and Engineers, 2. ed. , Prentice Hall, Englewood Cliffs, New Jersey 07632, US, ISBN 0-13-669201-X, US, 1988. Astronomy Notes (2004 Edition) by Nick Strobel, ISBN 0073122491, http://www.astronomynotes.com/ *Sample data are from experiments at Fiskeriforskning in Tromsø and from airborne campaigns at UNIS.