Area is a quantity expressing the size of a region of space. Surface area refers to the summation of the exposed sides of an object. Area (Cx2) is the derivative of volume (Cx3). Area is the antiderivative of length (Cx1).
Table of contents |
2 Some formulas 3 Ill-defined areas 4 External Link |
Units for measuring surface area include:
Units
Old British units, as currently defined from the metre:
- square foot (plural feet) - 0.09290304 square meters.
- square yard - 9 square feet - 0.83612736 square metres
- square perch - 30.25 square yards - 25.2928526 square metres
- acre - 160 square perches or 43,560 square feet - 4046.8564224 square metres
- square mile - 640 acres - 2.5899881103 square kilometres
For a two dimensional object the area and surface area are the same:
If one adopts the axiom of choice, then it is possible to prove that there are some shapes whose area cannot be meaningfully defined; see Lebesgue measure. Such 'shapes' (they cannot a fortiori be simply visualised) enter into Tarski's circle-squaring problem (and, moving to three dimensions, in the Banach-Tarski paradox). The sets involved will not arise in practical matters.Some formulas
Some basic formulas for calculating surface areas of three dimensional objects are: See also
An artist should feel free to add some example diagrams.Ill-defined areas