How does a rainbow get its colour?
Rainbows are optical and meteorological phenomena that cause a spectrum of light to appear in the sky when the Sun shines onto droplets of moisture in the Earth’s atmosphere. They take the form of a multicoloured arc, with red on the outer part of the arch and violet on the inner section of the arch A rainbow spans a continuous spectrum of colours. Traditionally, however, the sequence of colours is quantised. The most commonly cited and remembered sequence is red, orange, yellow, green, blue, indigo and violet. The rainbow’s appearance is caused by dispersion of sunlight as it goes through raindrops. The light is first refracted as it enters the surface of the raindrop, reflected off the back of the drop, and again refracted as it leaves the drop. The overall effect is that the incoming light is reflected back over a wide range of angles, with the most intense light at an angle of 40°–42°.
Rainbows are optical and meteorological phenomena that cause a spectrum of light to appear in the sky when the Sun shines onto droplets of moisture in the Earth’s atmosphere. They take the form of a multicoloured arc, with red on the outer part of the arch and violet on the inner section of the arch. More rarely, a secondary rainbow is seen, which is a second, fainter arc, outside the primary arc, with colours in the opposite order, that is, with violet on the outside and red on the inside. A rainbow spans a continuous spectrum of colours. Traditionally, however, the sequence of colours is quantised. The most commonly cited and remembered sequence, in English, is Newton’s sevenfold red, orange, yellow, green, blue, indigo and violet. “Roy G. Biv” and “Richard Of York Gave Battle In Vain” are popular mnemonics. Rainbows can be caused by other forms of water than rain, including mist, spray, dew, fog, and ice. Moreover, rainbows can have shapes other than a bow (arc), including stripes,
Light from the sun and some normal incandescent lamps look like as though as white actually consists of 7 colours. In Acronymn it read like this ROYGBIV for easy remembering:Richard Of York Gave Battle In Vain (mnemonic for colors of the rainbow). The splitting of white light into its colour components is called Dispersion.
