18.1 Electromagnetic Waves
18.2 The Electromagnetic Spectrum
18.3 Behavior of Light
18.4 Color
18.5 Sources of Light
How Do Color Filters Work?
Procedure
Place a piece of cardboard that has a slit cut into it in sunlight so that a beam of light passes through the slit. CAUTION Never look directly at the sun.
Create a rainbow by positioning a prism in the beam of light that has passed through the slit. Project the rainbow onto white paper.
Use colored markers to draw the colors in the order in which they appear on the paper.
Replace the paper. Place a red filter between the slit and the prism and draw the colors you see projected onto the paper.
Repeat Step 4 with a blue filter and then with a green filter.
Think About It
Inferring What happens to sunlight when it passes through a prism?
Observing Which colors did you see projected onto the paper while using each filter? Which colors didn't you see while using each filter?
Drawing Conclusions What can you conclude about what happens to sunlight as it passes through a filter?