College of Liberal Arts & Sciences
6A40.36 - Interference - Air and Water (Db. Slit)
Set up the equipment as shown with the double slit and beam at the lens end of the refraction trough. Several adjustments have to be made with the tank and the laser so that the two patterns fall one on top of the other. Due to the index of refraction of the water this probably means that the laser and the tank will not be exactly level. When properly adjusted a 3 bar pattern in the air should have a 4 bar pattern under it through the water.
- Brian Houser, "Demonstrating the Decreased Wavelength of Light in Water", TPT, Vol. 39, #4, Apr. 2001, p. 228.
- P.J. Ouseph, "Refraction of Diffracted Light", TPT, Vol. 36, #7, Oct. 1998, p. 420.
- G.R. Davies, "Interference and Diffraction Corridor Demonstrations", TPT, Vol. 33, #4, Apr. 1995, p. 244.
- Simon George and Robert Doebler, "Index of Refraction Using a Diffraction Pattern in a Fishtank", TPT, Vol. 29, #7, Oct. 1991, p. 462.
- Douglas C. Jenkins and Frank A. Smith, Jr., "Lecture Hall Demonstrations Or Fundamental Optics Made Obvious", TPT, Vol. 18, #1, Jan 1980, p. Back Cover.
- A. T. Mogill, "Velocity, Wavelength and Frequency Relations for Light", TPT, Vol. 13, #9, Dec 1975, p. 555.
- Richard F. Kotheimer, "Fish Tank, Laser Diffraction", TPT, Vol. 12, #5, May 1974, p. 307.
- T. Kallard, "Diffraction Refractometer", Exploring Laser Light, p. 203.
- Shyam Singh, "Diffraction Method Measures Refractive Indices of Liquids", Physics Education, Vol. 39, #3, 2004, p. 273.
Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist. The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose. The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources. Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks. These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage. Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.