7B11.80 - Spectral Lines/Spectroscopy - Food Coloring
See also 7B11.80 in Astronomy.
A band absorption may be produced by putting a water cell into the light path of the overhead projector or white light projector. A couple of drops of food coloring stirred into the cell will produce broad band absorption. Dr. Neff likes to do this in reverse!! He likes to start with food colored water and show the band. He then dilutes the colored water to make the band disappear.
- "Figuring Physics", TPT, Vol. 43, # 2, Feb. 2005, p. 117.
- Kenneth Brecher, "Do Atoms Really 'Emit' Absorption Lines?", TPT, Vol. 29, # 7, p. 454, Oct 1991.
- Don Hruby, "Doing Physics", TPT, Vol. 25, # 6, Sept. 1987, p. 402.
- O-285: "Holographic Grating-Antifreeze", DICK and RAE Physics Demo Notebook.
- O-740: "Fabrics & Theatrical Filters", DICK and RAE Physics Demo Notebook.
- Ron Hipschman, "Color Removal", Exploratorium Cookbook III, pp. 174.1 - 174.3.
- 2.5: Charles Taylor, The Art and Science of Lecture Demonstration, pp. 70-71.
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