Difference between revisions of "Sphere"

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A '''sphere''' is the collection of [[point]]s in [[space]] which are [[equidistant]] from a fixed point.  This point is called the ''center'' of the sphere.  The common distance of the points of the sphere from the center is called the ''radius''.
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A '''sphere''' is the collection of [[point]]s in [[space]] which are [[equidistant]] from a fixed point.  This point is called the ''center'' of the sphere.  The common distance of the points of the sphere from the center is called the ''[[radius]]''.
  
 
Spheres are the natural 3-dimensional analog of [[circle]]s.
 
Spheres are the natural 3-dimensional analog of [[circle]]s.
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The surface area of a sphere is <math>4\pi r^2</math>, where r is the radius.
 
The surface area of a sphere is <math>4\pi r^2</math>, where r is the radius.
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==See also==
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Geometry
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Revision as of 19:17, 23 September 2007

A sphere is the collection of points in space which are equidistant from a fixed point. This point is called the center of the sphere. The common distance of the points of the sphere from the center is called the radius.

Spheres are the natural 3-dimensional analog of circles.

The volume of a sphere is $\dfrac{4}{2}\pi r^3$, where r is the radius of the sphere.

The surface area of a sphere is $4\pi r^2$, where r is the radius.

See also

Geometry


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