Washington Comprehensive Assessment of Science (WCAS) Practice Test 2025 - Free WCAS Practice Questions and Study Guide

The process where energy is taken in by a substance is known as absorption. During absorption, materials capture energy, typically in the form of light, heat, or sound, converting it into internal energy. For instance, when sunlight hits a black surface, the surface absorbs light energy and converts it to heat, causing the temperature to rise. This principle can be observed in various contexts, such as plant photosynthesis, where plants absorb sunlight to create energy, or in thermal energy management, where dark materials are used to absorb solar energy efficiently.

In contrast, reflection involves bouncing off energy, such as light reflecting off a mirror. Transmission refers to the passing of energy through a substance without being absorbed; for instance, when light travels through a clear glass window. Refraction describes the bending of light as it passes from one medium to another due to a change in speed, not involving energy absorption. Thus, absorption is distinct in actively taking in energy, making it the correct choice in this context.