Hearing: loudness
Sound Intensity Level I:
level I is measured by power/m2 (Watt/m2 = W/m2)
range from hearing threshold to pain level :
intensity level at threshold of hearing: I 0 =10 -12 W/m2
intensity level at threshold of pain: 1 W/m2
(expressed in sound pressure, threshold is 2x 10-5 N/m2, which is
about 1/10,000 of pressure of sheet of paper on table)
If we measure intensity of sound in relation to threshold intensity
the answer will vary from 1 to 1,000,000,000,000 !!
How can an organism accommodate this huge intensity range?
How can we better express the intensity level?
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