Calculating Energy Absorbed by Eardrum from Intensity & Area

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To calculate the energy absorbed by the eardrum from a sound wave with an intensity of 80.1 dB and an area of 0.7x10^-4 m² over 4 minutes, the correct approach involves converting the intensity from decibels to power. The formula for intensity in decibels is 80.1 dB = 10 log10(P1/Po), where Po is typically 10^-12 W/m². After finding the power using the intensity and area, energy can be calculated by multiplying power by time in seconds. The initial calculation yielded 1.35, but the correct energy absorbed is 1.72, indicating a possible error in the conversion or calculation process. Understanding the logarithmic nature of decibels is crucial for accurate results.
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A sound wave with intensity of 80.1 dB is incident on an eardrum of Area = 0.7x10^-4. How much energy is absorbed by the eardrum in 4 minutes?


I know this much... Power = (Intensity)(Area)..so...P=(80.1)(0.7x10^-4)

and Energy = (power)(time) so...E = (80.1)(0.7x10^-4)(240 sec) = 1.35


However, this is not the correct answer. Am i not doing the right conversions or what?? What looks wring here? (the correct answer is 1.72)

I know it probably has something to do with converting dB to something...im just not sure how..
 
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Isn't a decibel a log of the ratio of the sound to a reference level?

So ... 80.1 dB = 10log10(P1/Po)

Po is what? 10-12W/m2 ?
 

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