At a distance of 10 meters form a point source, the intensity level is measured to be 70 dB. At what distance form the source well the intensity be 40 dB? How do you solve this?

At a distance of 10 meters form a point source, the intensity level is measured to be 70 dB. At what distance form the source well the intensity be 40 dB? How do you solve this?
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1 Answer

Answer :

Going on memory here….3db is half the intensity. The intensity is usually inversely proportional to r squared. The rest is math, so 70–40 is 30 or ten halves.
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