How A Rainbow Works? ->Refraction and Reflection
Picture taken from office late afternoon today… can you see the rainbow?
Two physical phenomena are at work within a rainbow: refraction and reflection. Refraction occurs each time light passes across a boundary from one substance to another, such as from air into water. As light crosses that boundary, the rays bend at different angles depending on the wavelength (color) of light. This is the familiar prism effect wherein “white” sunlight is broken into a spectrum of different colors from red to blue-violet.
The same thing that happens in a rainbow: white sunlight enters a raindrop and is broken into different colors heading in slightly different directions. The light is then reflected (and magnified) off the back of the raindrop and passes back into the air again, in the process being further refracted.
Under certain conditions, some of the light will bounce off the inside of the water droplet more than once, exiting at a different angle. This produces a weaker, secondary arc known as a double rainbow. In theory there are additional rainbows (third, fourth) but those are too faint to see.
Do you know why human uses scarecrow?
