PURPOSE: Demonstrate soap film interference in a complicated way.
DESCRIPTION: Light from the bright point source is focused by a 30 cm focal length convex lens onto a small wire loop with a soap film. The reflected light from the soap film is focused onto a screen by a 5 cm focal length convex lens, and the transmitted light is focused by a second 5 cm convex lens and positioned on the screen using a small front surface mirror.
SUGGESTIONS: We actually suggest avoiding this one because of the work required to set it up. Demonstration M4-21: SOAP FILM INTERFERENCE - LARGE SIMPLE VERSION is good.
REFERENCES: (PIRA 6D30.22)
EQUIPMENT: Point source with condenser lens and iris, 30cm focal length convex lens, two 5cm focal length convex lenses, small front surface mirror, small soap film wire loop with soap solution.
SETUP TIME: 15 min.
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