If the intensity level by 15 identical engines in a garage is 100 db, what is the intensity level generated by each one of these engines?
a) 44 db
b) 67 db
c) 13 db
d) 88 db

To develop this problem it is necessary to apply the concepts related to Sound Intensity.

By definition the intensity is given by the equation

Where,

I = Intensity of Sound

= Intensity of Reference

At this case we have that 15 engines produces 15 times the reference intensity, that is

And the total mutual intensity is 100 dB, so we should

Therefore each one of these engines produce D. 88dB.

gas and liquid