Applied Science - Physics (5B)   Lab
 OBJECTIVES: Investigating how kaleidoscopes work. Exploring properties of light. VOCABULARY: kaleidoscope mirror reflection symmetry MATERIALS: silver mylar 3.4 oz plastic portion cup small colored beads or any other small bright objects tape toilet paper tube paper towel Students make a kaleidoscope.
 BACKGROUND: Kaleidoscopes use the principles of symmetry and reflection to create brightly colored displays. A simple arrangement of mirrors produces multiple images of objects giving the effect that there are more than one object in an area. Reflection is when light bounces off a surface at the exact angle it enters. PROCEDURE: Draw the diagram on the right on the board. The ray of light that enters is called the incident ray and the ray that leaves is called the reflected ray.    Ask students where they have seen evidence of reflection. Perhaps they will mention seeing one in a mirror or shiny surface, or the reflection in a pond or lake. Make a list of their encounters with reflection. Ask students what is unique about a surface that gives good reflections; a polished, smooth surface is the best. A rough surface creates many reflections causing a blurry image.    The POST LAB goes over the reflection that occurs in a kaleidoscope the students have made. The lab centers around students making their own kaleidoscope and then comparing theirs to others in the lab to try and find out why they work. The only differences between the kaleidoscopes are the colors being reflected. Instruct students to compare theirs with a manufactured kaleidoscope provided in the module.    The directions for making a kaleidoscope are on the student's lab sheets. Students should notice there are 3 sections they see when looking through a kaleidoscope. Students will put beads or other transparent items small enough to fit into their kaleidoscopes. When the lab is completed, have students return the beads and small items. Conserve as much as the material as you can. The image will be blurred if the mylar is not straight. The students should see 3 sections when they look into these kaleidoscopes. They should conclude that reflection makes a kaleidoscope work. If students want to keep their kaleidoscopes, they can find items at home to put in it.