Circumference

The circumference is a Ligne closed Courbe limiting a Surface. It is also the Length of this closed curved line.

“Circumference” is a Synonyme with “Périmètre”, although this last has the Acception a little more general of a closed line of an unspecified form (polygonal or curve).

The word “circumference” is particularly adapted to the case of a disc, where it indicates the length of the Cercle of which all the points are at equal distance from a fixed point called center.

The concept of circumference well also applies to the case close to a ellipse

Length of a circumference (or circumference)

Case of the circle

One obtains the circumference of a circle by multiplying his Diamètre by the number π:

$C=\; \backslash \; pi\; \backslash \; times\; D$

One uses more usually like formulates:

$C\; =\; 2\; \backslash \; times\; \backslash \; pi\; \backslash \; times\; R$ où $R$ is the ray cercle

General case of the ellipse

$C\; =\; \backslash \; pi\; \backslash \; times\; (Ra\; +\; Rb)$ où $Ra$ and $Rb$ are the rays (or semi-axes) of the ellipse

Other particular circumferences

See Perimeter.

See too

• Perimeter

• pi

Random links:

Philippe of Vitry | Principal changes between the Treaty of Rome of 2004 and the treaty of Nice | Port-Saïd | Zanzibar (protectorate) | Battle of Henan-Hubei | Bataille_de_Lesnaya

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