The loudness L(x), measured in decibels, of a sound of intensity x, measured in watts per square meter, is defined as 
watt per square meter is the least intense sound that a human ear can detect. Determine the loudness, in decibels, of the sound.
At a rock concert by The Who, the music registered a loudness level of 120 decibels. The human threshold of pain due to sound averages 130 decibels. Compute the ratio of the intensities associated with these two loudness level to determine by how much the intensity of a sound that crosses the human threshold of pain exceeds that of this particular rock concert.
◦ The intensity of a sound that crosses the human threshold of pain is 10 times as intense as this rock concert.
◦ The intensity of a sound that crosses the human threshold of pain is 1000 times as intense as this rock concert.
◦ The intensity of a sound that crosses the human threshold of pain is 100 times as intense as this rock concert.
◦ The intensity of a sound that crosses the human threshold of pain is 0.1 times as intense as this rock concert.
Movement of sound waves through the human ear.
The Inverse-Square Law
Hue, Intensity, and Saturation
Loudness and Frequency
The breaking down of a sound—in this case, the sound of a clarinet—into its component sine waves ...
Seismic Intensity Map, Loma Prieta 1989