Two sources of sound have intensities 1w/m2 and 0.001w/m2 and a distance of 1m. what is the difference in sound intensity level (sil) of these two sources?

Sound Intensity is used to determine the intensity of sound waves. It has the units of decibel. We use the formula:

I(L) = 10log (I / Io)

We use Io equal to 10^-12 W/m2. We calculate as follows:

I(L) = 10log (1 W/m2 / 10^-12 W/m2) = 120 dB
I(L) = 10log (0.001 W/m2 / 10^-12 W/m2) = 90 dB

Therefore, the difference between the sources would be 30 decibels.