FUN DEMONSTRATIONS FOR INTERACTIVE TEACHING OF OPTICS, Amy Roberts, John Noé, and Harold Metcalf, Laser Teaching Center, Department of Physics & Astronomy, University at Stony Brook.

The Laser Learning Center provides an environment that encourages experimental exploration of physical concepts. Such open-ended, self-directed exploration can be invaluable in gaining an intuitive understanding of the physics taught in traditional courses, and students at every level take advantage of these resouces. In this project, we developed many simple demonstrations of fundamental optics phenomena in an effort to encourage students to tinker with available equipment.

For example, a small fishtank filled with cloudy water makes `rays of light' created by a laser pointer a tangible concept. Students can see and experiment with reflection and refraction caused by mirrors and lenses placed inside the tank. A bag of dissolved sugar siphoned into the bottom of our cloudy fishtank dramatically demonstrated the sophisicated concept of continuously-varying optical index-of-refraction. Students could also witness diffraction first-hand by shining light from a laser pointer through knit fabric or illuminating a ball bearing with laser light and looking at its projected image. While these are all excellent demonstrations of optical principles, the most important aspect of them is that they are simple enough for the students themselves to play with: they can shine the laser into the fishtank, move the ball bearing farther away from the light source, change the knit of the fabric grid, and observe for themselves what the effect is.

Everyone enjoys playing with these demonstrations, and because the equipment and setup is simple and inexpensive, hands-on exploration is readily available in many settings. High school students, participants in the Women and Science and Engineering program, professional scientists, graduate students, and high school teachers have all enjoyed playing with the equipment, and the hope is that the demonstrations easily set up in this lab will foster an interactive, experimental approach to learning physics that excites and involves students.

Celebration of Undergraduate Achievements 2 May 2001