Rainbow by Raindrops
A rainbow is a natural phenomenon where the dispersion of light is most visible. As you know, We can see a rainbow after rain because the water droplets bend and disperse the light. For example, if … more
Sunlight
Is Sun Rays Parallel?
Parallel sunlight The radiant energy of the sun spreads in every direction. However, since the sun and the earth are far apart, we assume that they are usually almost parallel. Ancient Greece’s Eratosthenes measured Earth’s size … more