A rainbow is formed from a glass prism through a process called refraction, where light bends and separates into its constituent colors.
Here's a breakdown of the process:
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Refraction: When white light enters the glass prism, it slows down because glass is denser than air. This change in speed causes the light to bend, an effect known as refraction.
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Dispersion: White light is composed of different colors, each with a unique wavelength. Different wavelengths of light bend at slightly different angles when they refract. This separation of light into its individual colors is called dispersion. The shorter wavelengths (violet/blue) bend more than the longer wavelengths (red).
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Color Separation: As the light exits the prism, it refracts again (bends further), enhancing the separation of colors. This results in the spectrum of colors we perceive as a rainbow – red, orange, yellow, green, blue, indigo, and violet – being visible. The prism acts to spread out (disperse) the light because each color bends a different amount.
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Emergence of Colors: The distinct colors emerge on the other side of the prism because of the varying degrees of bending of each wavelength. The result is a beautiful spectrum that mimics the colors of a natural rainbow.
In essence, the glass prism acts as a tool to reveal the different colors that make up white light by bending each color at a slightly different angle through refraction and dispersion.
