The sound of normal breathing is not very loud, with an intensityof about 11 dB at a distance of 1 m away from the face of thebreather.
Note that in this problem sound intensity in decibels isdenoted beta; intensityin \rm W/m^{2} is denoted I.

Part A
Given that a person with normal hearing canbarely detect a sound with intensity of 1 dB at a frequency of 1kHz (the sensitivity of the human ear peaking near 1 kHz), how faraway could this person detect another person breathingnormally?
Express the distance D_detect inmeters.
D_detect =3.16 m
Correct
Part B
In general, if a sound has intensity ofbeta dB at 1 mfrom the source, at what distance d_0from the source would the decibel level decrease to 0 dB? Since thelimit of hearing is 1 dB this would mean you could no longer hearit.
Express the distance in terms ofbeta. Be carefulabout your signs!