Mixing Colored Lights
What is color? How many different colors can be formed from a combination of only three colors? In this exploration, you will examine what happens when lights of three different colors are mixed.
Problem How can you produce a range of colors from three lights of different colors?
Materials
sources of red, blue, and green light
tape
large sheet of white paper
Skills Observing
Procedure
On a separate sheet of paper, make a copy of the data table shown.
Dim the room lights. Turn on the red light source and shine it on a large sheet of white paper. In your data table, record the colors you observe on the paper. CAUTION Do not touch lamps when they are on. They may be hot.
Place your hand between the light source and the paper as shown. Record the color of your hand's shadow.
Repeat Steps 2 and 3 with the blue and then with the green light source.
Now turn on the red and blue light sources and allow their beams to partially overlap. Record your observations in your data table.
Place your hand in the overlapping beams of light. Note the colors of any shadows that your hand makes. Record your observations.
Repeat Steps 5 and 6 with the red and green light sources. Then repeat Steps 5 and 6 with the blue and green light sources.
Turn on all three light sources and allow their beams to overlap. Record your observations.
Place your hand in the overlapping red, green, and blue beams. Note the colors of any shadows that your hand makes on the white paper. Record your observations.
Analyze and Conclude
Observing What happened when two colored lights overlapped?
Analyzing Data How did the combination of two colored lights produce the shadows you observed?
Applying Concepts Explain how combining three colored lights produced the colors you observed.
Drawing Conclusions From the shadows you observed when using three colored lights, what can you conclude about how colors of light combine? Explain your answer.
Examine the effects of red, green, and blue lights on the appearance of familiar objects, such as red apples and green grass. Prepare a report explaining your observations and present the report to the class.