Calculating Sound Levels in dB: How to Convert Intensity to Decibels

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To calculate the sound level in decibels for a sound wave with an intensity of 4.00 µW/m², the formula dB = 10log(I/Io) is used, where Io is 1E-12 W/m². The calculation yields 126.02 dB, but the book states the answer is 66 dB, indicating a possible misunderstanding of the intensity value. The correct intensity is confirmed as 4.00 µW/m², equivalent to 4.00 * 10^-6 W/m², not 4 W/m². The discrepancy highlights the importance of accurately interpreting units in sound intensity calculations.
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Homework Statement



Calculate the sound level in decibels of a sound wave that has an intensity of 4.00u "W/m2.

Homework Equations



dB = 10log(I/Io)

The Attempt at a Solution



dB = 10log(4/1E-12) = 126.02 db

Book says 66db. It vaguely covers this topic, not sure if I had missed something or not.
 
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That's 4.00 micro-watts per meter squared, or 4.00 * 10^-6 W/m^2. It isn't 4 W/m^2..
 
ideasrule said:
That's 4.00 micro-watts per meter squared, or 4.00 * 10^-6 W/m^2. It isn't 4 W/m^2..


pft... I completely overlooked that. Its getting late!
 

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