The amount of light reflected by an object is called what?

• A. Absorptivity
• B. Transmittance
• C. Reflectivity
• D. Radiance

Answer: (C)

Reflectivity is about how much light bounces off a surface. When light hits an object, some of it is reflected, some is absorbed, and some may be transmitted through if the material isn’t opaque. Reflectivity, the portion that is reflected, can be expressed as a fraction of the incident light (often 0 to 1, or 0% to 100%). This value helps explain why shiny, smooth surfaces look bright and mirrored, while dull or rough surfaces look darker because they reflect less light in a given direction.

Absorptivity refers to the portion absorbed by the material, not reflected. Transmittance is the portion that passes through the material. Radiance is a measure of the brightness of light in a specific direction from a surface, not specifically the fraction reflected.