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.
Marine myths measured
Mercalli Intensity Maps of Two Famous Bay Area Earthquakes
How We Localize Sound
Yinka Shonibare MBE, Nelson's Ship in a Bottle, Fourth Plinth, Trafalgar Square, London.
Distribution of skin color as measured by a reflectometer at a wavelength of 685 nm. The results are
Current intensity and the frequency of action potentials