The loudness of a sound is determined by what property of a sound wave?

Question

What is the name of the process by which a wave motion such as light or sound is turned back on reaching a boundary between two media?

Answer 1

amplitude
The amplitude of a sound wave determines its loudness or volume. A largeramplitude means a louder sound, and a smaller amplitude means a softer sound. In Figure 1 sound C is louder than sound B. The vibration of a source sets theamplitude of a wave.