Sound and Music - Mission SM2 Detailed Help

High intensity sounds are observed as relatively loud sounds. The sound waves that are most intense and perceived as loud sounds are those that have a _____. Identify the one characteristic that is unique of such sound waves.

Amplitude, Intensity and Energy:
The intensity of a wave is the rate at which energy passes through a cross-sectional area of the medium. Intense waves are associated with relatively large amplitude of vibrations of the particles of the medium. The more energy put into the wave by the source, the greater the amplitude of vibration of the particles, and the greater the intensity of the wave.

A holler is clearly perceived differently than a whisper. In a holler, particles of the medium are disturbed a relatively large amount from their resting position. A holler causes particles to vibrate about their rest position with a relatively large amplitude of vibration. The result is a relatively high intensity sound wave. At the observer's ear, particles of the medium are undergoing a relatively high amplitude vibration. Such vibrating particles will transmit a relatively high intensity wave to the ear. In turn, the observer perceives the sound wave to be loud.