What optical phenomenon occurs when light passes through a prism?

• A. Interference
• B. Scattering
• C. Refraction
• D. Reflection

Answer: (C)

When light passes through a prism, it undergoes refraction, which is the bending of light as it travels from one medium to another. This occurs because light travels at different speeds in different materials. In the case of a prism, light moves from air, a less dense medium, into the prism, which is made of glass, a denser medium. As the light enters and exits the prism, it bends due to the change in speed, which is governed by Snell's Law.

This bending is responsible for the separation of light into its component colors, creating a spectrum. This phenomenon is what allows us to see the different colors of light, such as red, orange, yellow, green, blue, indigo, and violet, as they are refracted at different angles. The angle of refraction depends on the wavelength of the light, meaning that different colors are bent by different amounts.

While interference, scattering, and reflection can also occur with light, they do not directly pertain to the primary action that takes place when light passes through a prism. Thus, refraction is the key optical phenomenon involved in this scenario.