Afterimage Flag

Complementary colors appear as an afterimage. Ask students to predict what will happen. Stare briefly at image, then look at white space. Key idea: Photoreceptors adapt and recover at different rates. Ask: Why do new colors appear after the picture is gone? Safety and cleanup: Short viewing time; no flashing. https://www.google.com/search?q=%22Afterimage%20Flag%22%20science%20demonstration%20experiment