Which term is used to compare two sound waves by relating their amplitudes or intensities?

• A. Amplitude
• B. Energy
• C. Density
• D. Frequency

Answer: (A)

Amplitude is the measure of how large a sound wave is, reflecting the pressure variation in the wave. When comparing two waves by how strong they are, you assess their amplitudes, since intensity (the power per area) is directly related to amplitude and, in fact, increases with the square of the amplitude. This makes amplitude the key quantity for comparing the relative strength of waves. Density describes a property of the medium, not the wave’s strength, and frequency relates to pitch rather than amplitude or intensity. Energy is linked to overall power, but the direct comparison of wave strength is captured by amplitude, with intensity tied to its square.