1. The problem statement, all variables and given/known data A rock group is playing in a bar. Sound emerging from the door spreads uniformly in all directions. The intensity level of the music is 116 dB at a distance of 5.77 m from the door. At what distance is the music just barely audible to a person with a normal threshold of hearing? Disregard absorption. Answer in units of m. So, Given- I1(dB) (the intensity level 5.77 meters from the door)=116 dB r1 (distance from door when intensity is 116 dB)= 5.77 m Io (Intensity at threshold of hearing)= 1e-12 Unknown- r2 (Radius at threshold of hearing) P (power of sound source) I1(w/m^2) (intensity 5.77 meters from door in watts/meters squared) 2. Relevant equations dB=10log(I/Io) P=4*I*π*r^2 r=√(P/4πI) 3. The attempt at a solution First, I changed the given Intensity into W/m^2 instead of hertz. dB=10log(I1/Io) 116=10log(I1/1e-12) 11.6=log(I1/1e-12) 10^11.6=I1/1e-12 (1e-12)(10^11.6)=I1 .3981071706=I1 So that's the Intensity at the spot from the door mentioned, so now I calculated the power source. P=4*I1*π*r1^2 P=4*.3981071706*π*5.77^2 P=166.5564633 So, now that I had the power source, I calculated the radius needed to achieve threshold of hearing r2=√(P/4πIo) r2=√(166.5564633/4*π*1e-12) r2=√(166.5564633/1.256637061e-11) r2=√1.325414222e13 r2=3640623.878 Doesn't seem right... 3.6 million miles seems overkill.