The loudness of a sound is determined by what property of a sound wave?
The loudness of a sound is primarily determined by the amplitude of the sound wave. Amplitude represents the maximum displacement of particles in a medium from their equilibrium position as the sound wave passes through it. Greater amplitude corresponds to a louder sound, while lower amplitude corresponds to a softer sound. Wavelength (A), frequency (B), and velocity (D) are important properties of sound waves but are not directly related to loudness.