How Does Sound Intensity Change with Fewer Firecrackers?

AI Thread Summary
When two firecrackers produce a sound level of 95 dB, the intensity can be calculated using the formula dB = 10 LOG I + 120. To find the sound level of one firecracker, one approach is to recognize that the intensity of two firecrackers is double that of one, which results in an increase of 3 dB. Therefore, to determine the sound level of a single firecracker, subtract 3 dB from 95 dB, yielding a sound level of 92 dB. This method effectively illustrates how sound intensity changes with the number of firecrackers. The discussion confirms that understanding the relationship between intensity and sound level is crucial for solving such problems.
Alicek
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Homework Statement


if two firecrackers produce a sound level of 95 dB when fired simultaneously at a certain place, what will the sound level be if only one is exploded?


Homework Equations



dB=10 LOG I + 120

The Attempt at a Solution


would I use 2I instead of I making an equation like 95 = 10 log 2I + 120 and then solve for one I?
Or set up the usual equation and then once I solve for I just divide it in half?
Also, I know that when intensity doubles, it goes up by 3 decibels, so do I just assume that two firecrackers is double the intensity of 1 and just subtract 3 decibels from the original 95?
 
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Alicek said:
Also, I know that when intensity doubles, it goes up by 3 decibels, so do I just assume that two firecrackers is double the intensity of 1 and just subtract 3 decibels from the original 95?

That's right.
 
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