Product Code: JLA_6_4_248

Authors:
Jeff Sweet
North Salinas High School Salinas, CA 93906, U.S.A.

Laser light is an instant attention‐getter in the classroom; thus any activity which uses the laser as an instructional tool is sure to enhance student motivation. This paper discusses two demonstrations and one experiment involving laser applications that the author has found to be particularly beneficial in terms of (1) instructional effectiveness and (2) arousing the interest of high school physics students. Brief descriptions follow. Refraction through lenses can be nicely illustrated by splitting laser light into several parallel beams and directing them through a fish tank filled with a scattering solution. When the light passes through a lens, the converging or diverging action is clearly seen in the liquid. Modulation is demonstrated by reflecting a modulated laser beam to a photometer, which is in turn connected to a modified radio for final output. The fact that the radio is receiving its information in an unusual way can be clearly shown by alternately blocking and unblocking the beam. Students can also determine the track spacing on a compact disc (CD) by analyzing the interference maxima produced when laser light reflects off the surface of a CD.