Which factor does NOT affect the intensity of a sound wave?

The intensity of a sound wave is influenced by various factors that affect how the sound propagates through a medium. One of the key principles regarding sound intensity is that it decreases with increasing distance from the sound source due to the spreading of the wavefronts. Additionally, the quality of the medium, which refers to its density and elasticity, plays a significant role in determining how effectively sound travels. The power of the sound source is another direct factor; higher power output results in greater intensity.

However, the color of the source – which typically refers to the visual characteristics of an object and does not have a direct correlation with sound properties – does not impact the intensity of the sound wave. Intensity is strictly related to the physical properties of the sound wave and its interaction with the medium, not the visual attributes of the source producing the sound. Therefore, the color of the source is the factor that does not affect the intensity of a sound wave.