Solving Sound Intensity Problem: Tips & Ideas

AI Thread Summary
To solve the sound intensity problem, the discussion focuses on calculating the distance from a loudspeaker where sound intensity changes from 100 dB to 60 dB. The method involves using the formula for intensity, I = Power / (4πr²), to first determine the power of the speaker based on the initial intensity. Participants suggest converting decibel levels to a linear scale to facilitate calculations, emphasizing the importance of understanding dB to intensity relationships. The conversation highlights the need for clarity in the calculations and the process of deriving the necessary distances. Overall, the thread seeks collaborative problem-solving strategies rather than direct answers.
El_Dustino
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This problem for some reason is giving me serious problem:

A 1.00 kHz tone issued from a loudspeaker has an intensity of 100. dB at a distance of 2.50 meters. If the speaker is assumed to be a point source, how far from the speaker will the sound (a) have an intensity of 60.0 dB and (b) be barely audible.


Now I'm not asking for someone to solve this problem for me at all. I was wondering if there is anyone who would have any ideas of how to arrive at the answer. I tried using [Intensity = Power \ (4)(3.14159)(r)^2] to solve for the power, and then use the same equation once more to solve for the distance at which the intensity is 60 dB. The teacher gave me the answers to this problem and asked me to find the method, which I thought would be easy, but I was wrong I guess.
 
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Your approach seems agreeable. Maybe if you would show us some calculations, in particular with the dB -> linear scale conversions.
 

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