Which term describes the change in direction of light as it passes from one medium to another, such as from air into glass?

Which term describes the change in direction of light as it passes from one medium to another, such as from air into glass?

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

Answer: (D)

Refraction is the bending of light as it passes from one medium to another with a different optical density. When light goes from air into glass, it slows down because glass has a higher refractive index, so the path changes direction at the boundary and the ray bends toward the normal. This change in direction due to a change in speed is what refraction describes. Other terms describe different effects: reflection is light bouncing off the surface, absorption is light energy being taken up by the material, and scattering is light being redirected in many directions.

Refraction is the bending of light as it passes from one medium to another with a different optical density. When light goes from air into glass, it slows down because glass has a higher refractive index, so the path changes direction at the boundary and the ray bends toward the normal. This change in direction due to a change in speed is what refraction describes.

Other terms describe different effects: reflection is light bouncing off the surface, absorption is light energy being taken up by the material, and scattering is light being redirected in many directions.