The question is:
A cylinder with a diameter of 1.5 cm produces a tone of 1000 Hz. The flow speed is 75 m/s. To what value should the flowspeed be reduced to reduce the noise by 5.0 dB?
The intensity I is a function of flowspeed c --> I=Prms^2 / (rhoc), but Prms is unknown. From intensity I you can calculate the sound intensity level B by B(dB) = 10log10(I/I0), in which I0 is 10e-12.
Sample Solution