What is the decibel level of a sound at 4% intensity of a 95dB sound?

Thread starter slaw155
Start date Sep 20, 2014
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To determine the decibel level of a sound at 4% intensity of a 95dB sound, the formula dB = 10log(I/I0) is used, where I0 is the reference intensity. First, calculate 4% of the intensity corresponding to 95dB, which is I = 0.04 * I95dB. Applying the logarithmic properties, the decibel level can be derived as dB = 10log(0.04 * I95dB/I0). The calculation results in a lower decibel level, reflecting the reduced intensity. This method effectively incorporates the percentage into the decibel calculation.

Sep 20, 2014

slaw155

What is the decibel level of a sound whose intensity is 4% that of a 95dB sound?

I know dB = 10log(I/Io) but don't know how to incorporate this for this question.

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Sep 20, 2014

jedishrfu

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Look at incorporating the percent to the I in the formula and then use log rules to pull out the percent factor.

Sep 20, 2014

slaw155

Thanks solved it

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