Rainbow Formation: The rainbow visible in the sky after rain is not magic, but a wonderful miracle of science. Know how a rainbow is formed from sunlight and water drops and why only 7 colors are visible in it.
Rainbow Formation: After the rain, when the sunlight comes out from between the clouds, sometimes a beautiful rainbow of 7 colors is seen in the sky. Everyone from children to elders becomes happy after seeing this. But do you know why rainbow is formed? The answer to this is hidden in science. Rainbow is not formed by any magic or miracle, but by sunlight, water drops and the rules of light.
What things are needed to form a rainbow?
Mainly 3 things are necessary for a rainbow to form-
– sunlight
– Small drops of water present in the air
– Correct direction of the person watching
this is the reason rainbow Mostly seen after rain or near waterfalls and fountains.
Read more- Why do we sweat more? Know when this sweating is normal and when it can become a sign of disease.
How is a rainbow formed?
Sunlight appears white to us, but in reality there are many colors hidden in it. When this white light enters a small rain drop, 3 processes happen-
1. Turning of light (Refraction) – As soon as the sun’s rays enter the water drop, its speed changes and it turns.
2. Dispersion: During turn, white light gets distributed into its different colors. Each color turns in a different direction.
3. Reflection: After this the light returns after hitting the inside of the drop and turns again while coming out. Because of this process we see a beautiful rainbow of colors in the sky.
Why are only 7 colors visible in the rainbow?
These 7 colors are usually visible in rainbow-
– Red
– orange
– Yellow
– Green
– Blue
– purple (indigo)
– Violet
In English it is also called VIBGYOR. According to science, there is a continuous spread of colors in light (Spectrum). We see 7 colors because the human eye can easily distinguish them.
Does every person see the same rainbow?
No, every person sees rainbow according to the direction (angle) of his viewing. Meaning, it is not necessary that the rainbow that you see is exactly the same as that seen by another person. For example, if two people are standing at some distance, then the light reaching both of them comes from different water drops.
Can a double rainbow also form?
Yes, sometimes light is reflected twice inside a water drop. In such a situation a double rainbow is visible. In this, the second rainbow is lighter and its colors appear in the reverse order.
Can rainbows also form at night?
Yes, but it is very rare. If the moonlight is very bright at night and there are water droplets in the air, a Moonbow can form. It looks much lighter than a normal rainbow.
Some statistics related to rainbow
– In rainbow, red color appears at a direction (angle) of about 42° and purple color at about 40°.
– The 7 main colors of the rainbow are red, orange, yellow, green, blue, indigo and violet. Generally rainbow is also called VIBGYOR.
– In a double rainbow, the second rainbow appears outside the first rainbow and its colors are in the reverse order.
– The size of a normal rain drop can be about 0.5 to 4 mm, and these drops help in the formation of rainbow.
– Lunar rainbow is very rare because the light of the moon is much less than the light of the sun.
Content Source: NASA, National Weather Service (NOAA), Encyclopaedia Britannica, American Meteorological Society (AMS), National Geographic.