AST 10G Lecture Notes - Lecture 3: Michael Faraday, Rarefaction, Diffraction
Document Summary
Newton (1642-1727) demonstrates (sunlight) contain all colors of visible light. Newton: white light cont. colors to begin w/ Warmth of sun=light is form of energy. Measure flow of energy in light: units of watts: 1 watt=1 joule/s. Blue light refracted the most, red light the least. Amount of light scattered is a function of particle size. Scattering is sensitive to color (like refracting) Gas in atmosphere blue is scattered more-composition of earth atm. Mars is pink, composition of atmosphere is different. Mirror reflects light in a particular direction (50*,80*,50*) Movies screen scatters light in all directions. Interactions btw light & matter determined appearance of everything @@ us. Why does the scene through a red tinted filer appear red: Filter transmits only red light (passing through filter) Matter can emit absorb, reflect, transmit (& refract) & scatter light. Light & matter determine appearance (enable us to figure out to study universe) Astronomy depended on using light to understand universe.