PURPOSE: Demonstrate Wien's law of radiation.
DESCRIPTION: The two holes appear equally dark, although the inside of one box is painted white and the other is painted black. The radiation emerging from the holes is a function only of temperature.
Click your mouse on the picture above to see the difference.
SUGGESTIONS: See Question of the Week #93 for information on using this demonstration to enhance class involvement.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Two identical boxes, except that one is black inside and one is white inside.
SETUP TIME: 10 minutes.