Summary: -Intensity, “I”, of a wave is the power delivered per unit area and is defined by I= P/A, where P is the rate at which the wave delivers energy (“W”) per unit area (“m2”).
-Intensity can also be defined as I=(1/2)pv(w)^2S^2m. p = mass density (in kg/m3), v = wave speed, w = angular frequency, and Sm = amplitude of sound wave.
When measuring sound levels, it is common to use the unit for logarithmic function “decibel” (dB).
B(I) = 0 dB + 10 log10 (I/I0). = expression of sound intensity