What Is the Sound Intensity Ratio Between a Rock Concert and a Jazz Fest?

AI Thread Summary
The sound intensity level at a rock concert is measured at 110 dB, while a jazz fest is at 100 dB. To find the ratio of sound intensity between the two events, one can use the formula B = (10 dB) log(I/I0). By rearranging the equations for each event and applying antilogs, the ratio of intensities can be calculated. The discussion highlights the importance of understanding logarithmic relationships in sound intensity measurements. Ultimately, the solution involves algebraic manipulation and the use of logarithmic properties.
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[SOLVED] Sound Intensity Level Ratio

Homework Statement



The sound intensity level at a rock concert is 110 dB, while that at a jazz fest is 100 dB. Determine the ratio of the sound intensity at the rock concert to that at the jazz fest.


Homework Equations


B=(10dB) log(I/Io)

The Attempt at a Solution



110=(10db) log (I/1.0*10^-12)
100=(10db) log (I/1.0*10^-12)

dont know where to go from here
 
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Ok, well let I_0=10^-12, then you have two expressions (taking log base 10)

110=10\log\left(\frac{I_1}{I_0}\right) \hskip1cm 100=10\log\left(\frac{I_2}{I_0}\right) and you want to find the ratio \frac{I_1}{I_2}. So, you need to perform some algebra on these expressions to make I_1 and I_2 the subject of the equations, respectively. Try dividing both sides of each equation by 10. After that you will need to take the inverse log of each side: how would you do this?
 
That was my problem, I forgot you could do antilogs. thanks you so much
 
tbontom said:
That was my problem, I forgot you could do antilogs. thanks you so much

No problem!
 
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