释义 |
Surface AreaSurface area is the Area of a given surface. Roughly speaking, it is the ``amount'' of a surface,and has units of distance squares. It is commonly denoted for a surface in 3-D, or for a region ofthe plane (in which case it is simply called ``the'' Area).
If the surface is Parameterized using and , then
 | (1) |
where and are tangent vectors and is the Cross Product.
The surface area given by rotating the curve from to about the -axis is
 | (2) |
If is defined over a region , then
 | (3) |
where the integral is taken over the entire surface.
The following tables gives surface areas for some common Surfaces. In the first table, denotes thelateral surface, and in the second, denotes the total surface. In both tables, denotes the Radius, theheight, the base Perimeter, and the Slant Height (Beyer 1987). Surface |  | Cone |  | Conical Frustum |  | Cube |  | Cylinder |  | Lune (Solid) |  | Oblate Spheroid |  | Prolate Spheroid |  | Pyramid |  | Pyramidal Frustum |  | Sphere |  | Torus |  | Zone |  |
Surface |  | Cone |  | Conical Frustum |  | Cylinder |  |
Even simple surfaces can display surprisingly counterintuitive properties. For instance, the surface of revolution of around the x-Axis for is called Gabriel's Horn, and has Finite Volume butInfinite surface Area. See also Area, Surface Integral, Surface of Revolution, Volume References
Beyer, W. H. CRC Standard Mathematical Tables, 28th ed. Boca Raton, FL: CRC Press, pp. 127-132, 1987.
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