6B40.55 - Spectrum Vs. Temperature - Wien's Law

Code Number:
Demo Title:
Spectrum Vs. Temperature - Wien's Law
Wein's Law
Area of Study:
White Light Weins Law Projector, Prism or Grating.

See also 6B40.55 in Astronomy.

Set up the Weins law projector making sure to put the Variac on the light not the fan.  Place the grating in the light beam.  With fan running turn the Variac on slowly and watch the spectrum go from the red portion of the spectrum to showing the whole spectrum.

  • James Lincoln, Steven Wetrich, "Color Temperature in Digital Photography and the Blackbody Spectrum", TPT, Vol. 59, #2, Feb. 2021, p. 140.
  • Mark L. Biermann, Debora M. Katz, Robert Aho, James Diaz-Barriga, Jerome Petron,  "Wien's Law and the  Temperature of the Sun",  TPT, Vol. 40, # 7, p.  398, Oct 2002.
  • Biman Das,  "Obtaining Wien's Displacement Law from Planck's Law of Radiation",  TPT, Vol. 40, # 3, p. 148, March 2002.
  • Ronald Ebert,  "Adapting Some Demonstrations for a Large Class",  TPT, Vol.  30, # 4, p. 239, April 1992.
  • William S. Wagner,  "Temperature and Color of Incandescent Lamps",  TPT, Vol. 29, # 3, p.  176, March 1991.
  • Mario Iona, "Red Hot", TPT, Vol. 26, # 5, May 1988, p. 265.
  • Don Hruby, "Doing Physics", TPT, Vol. 25, # 6, Sept. 1987, p. 402.
  • O-270:  "Prisms-Glass & Ethyl Cinnamate",  DICK and RAE Physics Demo Notebook.
  • S-170:  "Line Filament with R/G Filters",  DICK and RAE Physics Demo Notebook.
  • "Astronomy Demonstrations", PIRA News, Vol. 9, No. 3, pp. 21, January 1995.
  •  Yaakov Kraftmakher, "4.8 Thermal Radiation", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 267.
  • Tap-L comments by Cliff Bettis, 2004.
  • T. D. Rossing, C. J. Chiaverina, "# 9, Spectrum As a Function of Temperature", Light Science, Physics and Visual Arts, p. 149.

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