For the speed of sound in air, where t c is in degrees Celsius
Intensity of Sound The sound intensity is the sound power that passes perpendicular through a surface per unit of surface area.
Intensity of Sound If a source emits sound uniformly in all directions, one can imagine the energy spreading out in a spherical pattern.
Intensity of Sound The smallest sound intensity audible to the human hearing is 1 x 10 -12 W/m 2. This intensity is called the threshold of hearing (I 0 ). Since human hearing has a wide range, the intensity of audible sounds is compared to the intensity at the threshold of hearing.
Intensity of Sound The sound intensity of a vacuum cleaner is around 1 x 10 -5 W/m 2. Comparing this intensity to the threshold of hearing,
Intensity of Sound Due to the large comparison, it is more appropriate to express this relative intensity ( ) in a logarithmic scale.