Difference between revisions of "Diameter"

(Change to picture to asymptote)
m (Fix asymptote)
Line 1: Line 1:
 
A '''diameter''' of a [[circle]] is a [[chord]] of that circle which passes through the [[center]].  Thus a diameter divides the circle into two regions of equal [[area]] called [[semicircle]]s.
 
A '''diameter''' of a [[circle]] is a [[chord]] of that circle which passes through the [[center]].  Thus a diameter divides the circle into two regions of equal [[area]] called [[semicircle]]s.
  
{{asy image|<asy>unitsize(2cm);draw(unitcircle,black);pair O = (0,0);pair A = (-1,0);pair B = (1,0);draw(A--O--B);label($O$,O);label($A$,A);label($B$,B);</asy>|right|This circle has diameter <math>AB</math> since center <math>O</math> lies on <math>AB</math>.}}
+
{{asy image|
 +
<asy>
 +
unitsize(1cm);
 +
draw(unitcircle,black);
 +
pair O = (0,0);
 +
pair A = (-1,0);
 +
pair B = (1,0);
 +
draw(A--O--B);
 +
label("$O$",O,S);
 +
label("$A$",A,W);
 +
label("$B$",B,E);
 +
</asy>|right|This circle has diameter <math>AB</math> since center <math>O</math> lies on <math>AB</math>.}}
  
  

Revision as of 18:06, 16 January 2025

A diameter of a circle is a chord of that circle which passes through the center. Thus a diameter divides the circle into two regions of equal area called semicircles.

[asy] unitsize(1cm); draw(unitcircle,black); pair O = (0,0); pair A = (-1,0); pair B = (1,0); draw(A--O--B); label("$O$",O,S); label("$A$",A,W); label("$B$",B,E); [/asy]

Enlarge.png
This circle has diameter $AB$ since center $O$ lies on $AB$.


Diameter of a set

The diameter of more general sets can also be defined. In any given metric space (that is, anywhere you can measure distances between points such as normal Euclidean 3-D space, the surface of the Earth, or any real vector space) the diameter of a bounded set of points is the supremum of the distances between pairs of points. In the case where the set of points is a circle, the diameter is the length of the diameter of the circle.

This article is a stub. Help us out by expanding it.