In the color equation, the atoms that compose an object can cause which effect?

• A. Selective reflection
• B. Selective absorption
• C. Emission of light
• D. Selective scattering

Answer: (B)

The color you see arises from which wavelengths of light the material absorbs versus which it reflects. Atoms and molecules have specific energy levels, so when white light shines on the object, photons with certain energies are absorbed by electronic transitions. Those absorbed wavelengths are removed from the spectrum that reaches your eyes, while the wavelengths that aren’t absorbed are reflected or transmitted. The combination of the remaining wavelengths gives the object its color. This is selective absorption. Other effects like selective reflection, selective scattering, or emission of light don’t typically explain the color of ordinary objects under white light: reflection describes broad, non-specific color bounce, scattering involves redirection by particles, and emission would mean the object glows by itself rather than simply reflecting wavelengths.