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: None.