To find the loudness of a sound when you know its intensity, you take the base-10 logarithm of its intensity, over the reference intensity of 1 picowatt per square meter.

UB undergraduates measure the sound-intensity levels around the North Campus for a physics of music course.

Students learn to calculate intensity and relative intensity and to relate intensity, decibel level, and loudness. The phenomenon of resonance is explained and examples given.

Although this result suggests subwavelength focusing or resolution beyond the diffraction limit, the authors point out that this is not the case — such narrow intensity profiles cannot be ...