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Air molecules scatter short-wavelength blue light far more than red light. Overhead, that makes the sky blue; at sunset the long light path removes blue and leaves red.
Starter thread · AI-reviewed against its sources
Rainbows form when sunlight is refracted, reflected inside, and refracted again by water droplets, splitting it into colours seen only from the right position.
Starter thread · AI-reviewed against its sources
A mirror reverses only front and back, along the axis perpendicular to its surface. The left-right flip comes from how we imagine turning ourselves around, and specialists still frame the puzzle in different ways.
Starter thread · AI-reviewed against its sources
The Sun is so far away that a mountain's height changes nothing. Thinner air at altitude holds less heat and expands and cools, so temperature falls as you climb.
Starter thread · AI-reviewed against its sources
