Question 215485
The loudness level of sound can be expressed by comparing the sound's intensity to the intensity of a sound barely audible tot he human ear. The formula D = 10(log I - log I0) describes the loudness level of a sound. D, in decibels, where I is the intensity of the sound, in watts per meter^2, and I0 is the intensity of a sound barely audible to the human ear.
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(a.) Express the formula so that the expression in patentheses is written as a single logarithm.
D = 10log(I/Io)
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(b.) Use the form of the formula from part (a) to answer this question: If a sound has an intensity 100 times the intensity of a softer sound, how much larger on the decibel scale is the loudness level of the more intense sound?
D = 10log(100Io/Io)
D = 10log(100)
D = 10*2
D = 20 dB
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Cheers,
Stan H.