In physics, an **inverse-square law** is any physical law stating that a specified physical quantity or intensity is inversely proportional to the square of the distance from the source of that physical quantity. In equation form:

The divergence of a vector field which is the resultant of radial inverse-square law fields with respect to one or more sources is everywhere proportional to the strength of the local sources, and hence zero outside sources. Newton's law of universal gravitation follows an inverse-square law, as do the effects of electric, magnetic, light, sound, and radiation phenomena.

Read more about Inverse-square Law: Justification, Field Theory Interpretation

### Other articles related to "law":

**Inverse-square Law**- Field Theory Interpretation

... For an irrotational vector field in three-dimensional space the

**inverse-square law**corresponds to the property that the divergence is zero outside the source ... vector field falls off with the distance "r" following the inverse (n − 1)th power

**law**, given that the space outside the source is divergence free ...

### Famous quotes containing the word law:

“If he who breaks the *law* is not punished, he who obeys it is cheated. This, and this alone, is why lawbreakers ought to be punished: to authenticate as good, and to encourage as useful, *law*-abiding behavior. The aim of criminal *law* cannot be correction or deterrence; it can only be the maintenance of the legal order.”

—Thomas Szasz (b. 1920)