Which term describes energy taken in by a material and often converted to heat?

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

Answer: (D)

Absorption is about energy being taken into a material and often turning into heat. When light or other radiation encounters a material, some wavelengths are absorbed by the material’s molecules, which increases their internal energy and raises the temperature. This is why dark or black surfaces feel warmer in the sun—they absorb more light rather than letting it pass through or bounce away. Transmission would mean the energy passes through the material, not taken in; reflection means energy bounces off; refraction is the bending of light as it enters a new medium, not about energy being absorbed. So absorption best describes energy taken in and converted to heat.