6B40.30 - Black Body Radiation

2700k Bulb
2700k Bulb
5000k Bulb
5000k Bulb
6500k Bulb
6500k Bulb
Code Number:
Demo Title:
Black Body Radiation
Area of Study:
Optics & Astronomy
Computer, Ocean Optics Spectrometer, CFL light bulbs - 2700K, 5000K, 6500K, and Variacs.

See also 6B40.30 in Astronomy.

Video and Editing Credit: Jonathan M. Sullivan-Wood.

Turn the lights on, let them warm up for a few seconds, and point the spectrometer sensor cable at the desired light.  Set the spectrometer to a boxcar setting of about 100.  A broad Black Body radiation curve can then be seen.  The peak of that curve will shift to different wavelengths as you look at the different Kelvin rated bulbs.

  • I. Gonzalez de Arrieta, "Wien's Displacement Law and Blackbody Radiation Quartiles", TPT, Vol. 59, #6, Sept. 2021, p. 464.
  • "Figuring Physics", TPT, Vol. 40, # 4, Apr. 2002, p. 252.

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