How to Reflect Mirrors With Light for a Science Project in Color

Prisms can be found in art, craft, collectible and educational stores.

Mirrors can be used to reflect and focus light beams to demonstrate the separation and culmination of the colors that are present in white light. Concave mirrors reflect light in a predictable course, allowing the directed beam to be shot through a prism. When the white light hits the angles of the prism, it is split into the rainbow color spectrum that is often seen after rainstorms. Reflect light colors through prisms and mirrors to make a science project that shows your understanding of color and light.

Things You'll Need

• Full spectrum light (optional)
• Magnifying glass
• Small flat mirror
• Clay
• Protractor
• 2 prisms
• Concave mirror
• Blank white paper

Instructions

1. Take all the science project supplies outside on a sunny day or set up a full spectrum light if the demonstration must be done indoors or at night. Full spectrum bulbs are sold at most hardware and garden supply stores.

2. Move a magnifying glass up and down below the light source until you focus the light into a beam the size of a pea.

3. Mount a small, flat mirror on a lump of clay at a 45-degree angle above a flat surface. Measure until you achieve the proper angle by placing a protractor on the flat surface next to the mirror.

4. Place a prism six inches in front of the flat mirror. Practice focusing the beam of light straight down from the source and onto the center of the angled mirror so that it shoots through the middle of the prism.

5. Spin the prism slowly until the light coming out has been split into the colors of the rainbow.

6. Place a small concave mirror in position a couple inches away from the prism to catch and reflect all the colored light beams.

7. Adjust the position of the concave mirror to shoot all the colored light beams into a second prism. Press the concave mirror into a lump of clay so it will stay in position as you spin the second prism until a single beam of white light comes out.

8. Catch the beam of recollected white light on a sheet of blank paper to demonstrate the fact that the colors in the light have come back together.

Tips & Warnings

• A second set of hands is very helpful during the setup and adjustment phase of the demonstration. Ask a volunteer to keep the focused light on the center of the flat mirror and through the first prism while you finish the project.

References

• Phy6.org: Educational Web Sites on Astronomy, Physics, Spaceflight and the Earth's Magnetism: The Many Colors of Sunlight
• Crayola: Lesson Plans: Every Color in the Rainbow