CBSE Class 10 Answered
After the rainfall some water droplets remain suspended in the atmosphere. When sunlight falls or passes through these droplets at low altitude or angle. The light is dispersed into several colors with the water droplets acting as a prism. As a ray of sunlight enters a raindrop, its color components are bent, or refracted at different angles and reflected off the raindrop's inner surface. Then as it leaves the rain drop, the light is bent once again. Red, the longest wavelength is reflected to the highest or outer most arcs; violet, the shortest wavelength, to the lowest or innermost arc; violet, the shortest wavelength, to the lows or innermost arc, yellow and green, two arcs between the two. A rainbow is thus said to be formed making the shape of the arc. The rainbow can more often be seen when sun is at the low elevation and is shining at the back of the observer. The rainbow effect is also commonly seen near waterfalls or fountains because the concentration of water droplets is higher in the nearby region. So we can say that white light means the sunlight is mixture of different colors and the water droplets act as filter, which breaks it to turn into rays of different colors and thus forms a rainbow.