Sphere - Revision history

Karl Jones: /* See also */

2016-05-25T00:08:35Z

‎See also

Karl Jones at 18:29, 13 May 2016

2016-05-13T18:29:10Z

Karl Jones: /* See also */

2016-05-13T18:28:53Z

‎See also

Karl Jones: /* External links */

2016-04-25T14:23:51Z

‎External links

Karl Jones: /* External links */

2016-04-21T00:17:46Z

‎External links

Karl Jones: /* See also */

2016-01-28T14:43:50Z

‎See also

Karl Jones: Created page with "A '''sphere''' (from Greek σφαῖρα — sphaira, "globe, ball") is a perfectly round geometrical object in three-dimensional space that is the surface of a completely rou..."

2016-01-28T14:41:37Z

Created page with "A '''sphere''' (from Greek σφαῖρα — sphaira, "globe, ball") is a perfectly round geometrical object in three-dimensional space that is the surface of a completely rou..."

New page

A '''sphere''' (from Greek σφαῖρα — sphaira, "globe, ball") is a perfectly round geometrical object in three-dimensional space that is the surface of a completely round ball, (viz., analogous to a circular object in two dimensions).

== Description ==

Like a [[circle]], which geometrically is a two-dimensional object, a sphere is defined mathematically as the set of points that are all at the same distance r from a given point, but in three-dimensional space.

This distance r is the radius of the ball, and the given point is the center of the mathematical ball.

The longest straight line through the ball, connecting two points of the sphere, passes through the center and its length is thus twice the radius; it is a diameter of the ball.

== Distiction between sphere and ball ==

While outside mathematics the terms "sphere" and "ball" are sometimes used interchangeably, in mathematics a distinction is made between:

* The sphere (a two-dimensional closed surface embedded in three-dimensional Euclidean space)
* The ball (a three-dimensional shape that includes the sphere as well as everything inside the sphere).

The ball and the sphere share the same radius, diameter, and center.

== See also ==

* [[Geometry]
* [[Sphere packing]]

== External links ==

* [https://en.wikipedia.org/wiki/Sphere Sphere] @ Wikipedia

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 == See also ==
 * [[Circle]]
 * [[Diameter]]
 * [[Geometry]]
 * [[Pi]]
 * [[Sphere packing]]
 == External links ==

← Older revision		Revision as of 18:29, 13 May 2016
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−	A '''sphere''' (from Greek σφαῖρα — sphaira, "globe, ball") is a perfectly round geometrical object in three-dimensional space that is the surface of a completely round ball, (viz., analogous to a circular object in two dimensions).	+	A '''sphere''' (from Greek σφαῖρα — ''sphaira'', "globe, ball") is a perfectly round geometrical object in three-dimensional space that is the surface of a completely round ball, (viz., analogous to a circular object in two dimensions).

	== Description ==		== Description ==

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 == See also ==
 * [[Geometry]]
 * [[Pi]]

← Older revision		Revision as of 14:23, 25 April 2016
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	[[Category:Geometry]]		[[Category:Geometry]]
	[[Category:Mathematics]]		[[Category:Mathematics]]
		+	[[Category:Sphere]]

← Older revision		Revision as of 00:17, 21 April 2016
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	* [https://en.wikipedia.org/wiki/Sphere Sphere] @ Wikipedia		* [https://en.wikipedia.org/wiki/Sphere Sphere] @ Wikipedia
		+
		+	[[Category:Geometry]]
		+	[[Category:Mathematics]]