KS3 Waves Practice Test 2025 – Complete Exam Prep Resource

Amplitude in the context of a wave specifically refers to the maximum displacement of particles from their rest position. This means it measures how far the wave moves away from its undisturbed state, which is an important characteristic that relates to the energy of the wave. A higher amplitude indicates that the wave carries more energy, while a lower amplitude means less energy.

Understanding amplitude is essential when studying waves because it affects the intensity or loudness in sound waves and the brightness in light waves. This concept distinguishes amplitude from other wave characteristics, such as wavelength, which measures the distance between consecutive peaks, wave speed, which is the rate at which the wave travels through a medium, and frequency, which counts how many wave cycles occur in a second.