(Colloquial form of GAUSS' LAW)

*"When something passes **out* of a region,

it is no longer*inside* that region."

it is no longer

How, you may ask, can such a dumb tautology teach us
anything we don't already know?
The power of GAUSS' LAW rests in its combination with
our knowledge of *geometry* (*e.g.* the surface area *A*
of a sphere of radius *r* is
)
and our instinctive
understanding of *symmetry* (*e.g.* there is no way for
a *point* of zero size to define a favoured *direction *).
When we put these two skills together with GAUSS' LAW
we are able to easily derive some not-so-obvious
*quantitative* properties of many commonly-occurring
natural phenomena.

Jess H. Brewer - Last modified: Mon Nov 16 17:24:55 PST 2015