Doesn't matter whether it's radio or light or sound; if it's a point source (zero-dimensional) in three-dimensional space, it's inverse square falloff. If it's

Doesn't matter whether it's radio or light or sound; if it's a point source (zero-dimensional) in three-dimensional space, it's inverse square falloff. If it's a line source (one dimensional), it's inverse (one over first power of distance) falloff. This is why fluorescent lights are so effective at illuminating large warehouses: At near distances, they are approximately line sources.