The inverse square law
- The intensity of an isotropic sound wave decreases as the
square of the distance from its source
- Since intensity is proportional to the square of the amplitude,
the amplitude of a sound wave decreases as the inverse of the
distance from its source
- Close to their source, sound waves are best described as spherical
waves with a decreasing amplitude
- Far from their source, sound waves may be approximated as
plane waves with constant amplitude
-
Viewgraph 4
-
Viewgraph 5
-
Viewgraph 8
-
Viewgraph 9
-
Viewgraph 10