Color Mixing
Topic/Concept: Color Mixing
Type of Activity: small group
Prerequisite knowledge required: none
Resources required: water, food coloring, flashlight, prism, lamps with red, green, and blue filters to project circles on the wall in those colors
Learning Objectives: Understand that mixing colors of light is different than mixing paint/dyes. Understand that white light is made of all the colors combined
Common misconceptions: when red, green, and blue light are added together they will produce black
Detailed description of activity: Start with red, green, and blue food coloring. Have each student put a drop of the food coloring in the water and have the other students guess what color will result after each combination. Shine the flashlight through the prism and make a rainbow. Talk about how the prism is bending the light and each color gets bent a different amount so that they show up separated. Talk about how the light coming out of the flashlight is white but it is really a combination of all the colors they see in the rainbow. Then show them the three colored spots and ask which they would like to combine. Have them guess the outcome. Finally, ask them what will happen when all three colors are combined and ask them to think about the prism. Combine all three and emphasize that the prism separates white light into all the colors that make it up and that combining the three spots is like putting white light back together.
Assessment: this is done while interacting with the students.
Associated files and images: none
Comments: this activity is meant to take up only ~ 15 minutes and is geared towards elementary/middle school students in an outreach setting. more detail could be added to it in order to make it appropriate for older age groups.