This activity help kids understand diffraction and learn where rainbows come from.
The sun may look yellow, but the light we receive from it is actually white light. White light is a combination of every color in the rainbow and can be separated into individual colors. For example, when white light hits an apple, red is the only color that gets reflected. So how do we get every color to be separated and reflected? A CD is a mirrored surface with spiral tracks or pits. These tracks are evenly spaced and diffract the sunlight (separating the colors). Because the CD’s surface is mirrored, the light is reflected to your eye. The paper is blocking some light rays from the CD, but letting others through creating all kinds of patterns and designs!