How do prisms alter the appearance of light?

• A. They scatter light into random directions
• B. They amplify the intensity of light
• C. They disperse light into its constituent colors
• D. They absorb certain wavelengths entirely

Answer: (C)

Prisms alter the appearance of light primarily by dispersing it into its constituent colors. This phenomenon occurs due to the refraction of light as it passes through the prism, which is typically made of transparent materials like glass. When white light enters the prism, it is slowed down and bent at different angles because the various colors that comprise white light—such as red, orange, yellow, green, blue, indigo, and violet—have different wavelengths. Each color is refracted by a different amount, resulting in the separation of light into a spectrum. This is why when you look at light passing through a prism, you can see a rainbow of colors appearing, demonstrating the principle of dispersion.

Understanding this process showcases how prisms are invaluable in various applications, such as spectroscopy, where they are used to analyze the composition of light from different sources.