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please give a brief description of the formation of the rainbow.Asked by dipankar 4 months ago
Answers (1)
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Raindrops act like prisms and disperse the different wavelengths and colours of white light to form a rainbow.
The light is first refracted entering 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°.
White light separates into different colours on entering the raindrop due to dispersion, causing red light to be refracted less than blue light.
Blue light (shorter wavelength) is refracted at a greater angle than red light, but due to the reflection of light rays from the back of the droplet, the blue light emerges from the droplet at a smaller angle to the original incident white light ray than the red light. Due to this angle, blue is seen on the inside of the arc of the primary rainbow, and red on the outside.