Rainbows are natural optical phenomena that occur when sunlight is refracted, or bent, and then reflected inside raindrops in the atmosphere. The process can be explained in the following steps:
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Sunlight: Rainbows are formed by sunlight, which is composed of a mixture of different colors, or wavelengths, ranging from red to violet.
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Refraction: When sunlight encounters a raindrop, it enters the drop and undergoes refraction, which means it changes direction due to the change in speed as it moves from air to water.
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Dispersion: The light is also dispersed as it enters the raindrop, meaning that the different wavelengths of light separate and spread out.
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Internal Reflection: Once inside the raindrop, the light undergoes multiple internal reflections off the inner surface of the raindrop.
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Refraction and Exit: After the internal reflections, the light refracts again as it leaves the raindrop and returns to the air.
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Separation of Colors: As the light exits the raindrop, it undergoes further dispersion, separating into its component colors. The different wavelengths of light are bent at different angles, resulting in the separation of colors.
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Formation of a Circle: The separated colors then reach the observer's eye. However, the observer typically sees a semi-circular arc of colors rather than a full circle. This is because the ground obstructs the lower half of the circle, making it invisible.
The specific angle at which the light is refracted and reflected within the raindrop determines the size and shape of the rainbow. The primary rainbow appears as a semi-circle with red on the outer edge and violet on the inner edge. Sometimes a secondary, fainter rainbow can be seen outside the primary rainbow with the order of colors reversed.
It's important to note that rainbows are only visible when there are raindrops in the air and the observer is positioned between the sun and the raindrops. The angle of the sun with respect to the raindrops determines the height and visibility of the rainbow.
Enjoy a rainbow with our high-quality umbrellas below!
1. Colour Changing, "Happy Days"
A one-of-a-kind umbrella that features a white and black polka dot design that turns into happy faces when it gets wet.
2. Colour Changing, "Pizza Party"
A one-of-a-kind umbrella that features a white and black triangle design that turns into pizza slices when it gets wet.
3. Reflective, "Hi-Beams"
This umbrella is equipped with reflective fabric that lights up like a disco ball when hit by light.