Video narration
Why does sunlight turn into a rainbow after rain? Watch sunlight pass through a raindrop, like sunlight through a wet window. As it enters water, refraction bends it. But here's the surprise: white light separates because each color bends differently. They reflect inside the drop, then refract out toward your eyes. With the Sun behind you, many raindrops send different colors your way. That answers it: rainbows form when drops bend, split, reflect, and redirect sunlight.