Download presentation
Presentation is loading. Please wait.
Published byMagdalene Wilcox Modified over 9 years ago
1
Incandescent Light Featuring Louie the Lightning Bug Melissa Long Allison M c Coy Junior Lab December 10, 2003
2
History of the Light Bulb 70,000 BC - first lamp invented. 1809 - Humphry Davy, an English chemist, invented the first electric light. 1854 - Henricg Globel, a German watchmaker, invented the first true light bulb. 1875 - Henry Woodward and Matthew Evans patented the light bulb. 1879 - Thomas Alva Edison invented first successful incandescent light bulb 1907 - Tungsten was first used for light bulb filaments
3
Blackbody Radiation The spectrum of a blackbody depends only on the temperature of the object. Incandescent Lights give off blackbody radiation.
4
Incandescent Light ÛElectric current passes through metallic filament ÛFilament heats producing visible light ÛFilament enclosed in evacuated glass bulb or a bulb containing an inert gas Û http://www.bulbs.com/lightingguide/tech_incandescentdiagram.asp
5
Halogen Lamp Û Step 1: Tungsten atoms evaporate from the hot filament and move toward the cooler bulb-wall. Û Step 2: Tungsten, oxygen and halogen atoms combine at the bulb- wall to form tungsten oxyhalide molecules. Û Step 3: The bulb-wall temperature keeps the tungsten oxyhalide molecules in a vapor. The molecules move toward the hot filament where the higher temperature breaks them apart. Û Step 4: Tungsten atoms are re- deposited on the cooler regions of the filament. Û http://americanhistory.si.edu/lighting/tech/th.htm W(s) + 3Cl 2 (g) WCl 6 (s) WCl 6 (s) W(s) + 3Cl 2 (g) heat Û http://www.webelements.com/webelements/elements/text/W/chem.html
6
Wavelength of Our Light Sources
7
Louie The Lightning Bug brought to you by CIPCO’s Electric Universe:The Power of Learning (http://cipco.electricuniverse.com/html/index.html) zebu.uoregon.edu/~imamura/ 123/lecture-1/cmbr.html http://inventors.about.com/library/inventors/bllight.htm http://americanhistory.si.edu/lighting/tech.htm http://www.bulbs.com/lightingguide/tech_incandescentdiagram.asp http://www.webelements.com/webelements/elements/text/W/chem.html
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.