Medical How are decibels calculated on a logarithmic scale?

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SUMMARY

Decibels (dB) are a logarithmic unit used to measure sound energy, with zero decibels defined as the absolute threshold for hearing. Each increase of 10 dB represents a ten-fold increase in sound intensity, making a 60 dB conversation 10,000 times louder than a 20 dB whisper. The formula I(dB) = 10*log10(I/I0) is essential for understanding this logarithmic scale, where the number of zeros in the intensity value corresponds to the dB level. For instance, 60 dB equates to 1 million, as indicated by the six zeros following the 1.

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Decibels are the measuring unit for sound energy. The absolute threshold for hearing is arbitrarily defined as zero decibels. Every 10 decibels correspond to a ten-fold increase in sound. Thus, normal conversation (60 dB) is 10,000 time louder than a 20 dB whisper.

I don't understand the math of the 10 fold system.
Could someone go into detail of it for me?

I just don't see how that works.

10 db = 100
20 = 1000
30 = 10000?

i don't understand the system here.
 
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It's a log scale

<br /> I(db) = 10*log_{10}(\frac{I}{I_0})<br />

For example

<br /> 10db = 10*log_{10}(10)<br />

<br /> 30db = 10*log_{10}(1000)<br />


<br /> 60db = 10*log_{10}(1000000)<br />
 
I don't understand that log stuff or I think I'd have this understood by now.

==update==
Ah, I understand it a bit better now after doing some math work. Thank you.

simply the 6 part of 60 could signify 6 zeros after the 1, making it 1 million.
 
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