Benham Disk Color Illusion

Faint colors may appear even though the disk has no colored ink. Ask students to predict what will happen. Spin the black-and-white pattern. Key idea: Different visual receptors respond at slightly different rates. Ask: Are the colors really printed there? Safety and cleanup: Stop if anyone feels visually uncomfortable. https://www.google.com/search?q=%22Benham%20Disk%20Color%20Illusion%22%20science%20demonstration%20experiment