Which factor of the vocal cords controls the pitch of the sound produced?

The tension of the vocal cords plays a crucial role in controlling the pitch of the sound produced during phonation. When the vocal cords are stretched and placed under higher tension, they vibrate more quickly, resulting in a higher pitch. Conversely, when the vocal cords are relaxed and have less tension, they vibrate more slowly, leading to a lower pitch. Thus, by adjusting the tension of the vocal cords, the muscles in the larynx can modify the frequency of the sound waves produced, allowing for the variation in pitch that is essential for speech and singing.

Length, width, and mass of the vocal cords all contribute to sound production, but it is primarily the tension that has the most direct impact on pitch. Length can affect the fundamental frequency, and a thicker or wider cord may affect the overall quality and loudness of the sound, but it is the adjustment of tension that most significantly influences the pitch of the sound produced.