Radial line
Encyclopedia
This article is about the mathematical concept. For the medical meaning, see arterial line
Arterial line
An arterial line, or art-line, or a-line, is a thin catheter inserted into an artery. It is most commonly used in intensive care medicine and anesthesia to monitor the blood pressure real-time , and to obtain samples for arterial blood gas measurements. It is not generally used to administer...

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A radial line is a line
Line (geometry)
The notion of line or straight line was introduced by the ancient mathematicians to represent straight objects with negligible width and depth. Lines are an idealization of such objects...

 passing through the center
Center (algebra)
The term center or centre is used in various contexts in abstract algebra to denote the set of all those elements that commute with all other elements. It is often denoted Z, from German Zentrum, meaning "center". More specifically:...

 of a circle
Circle
A circle is a simple shape of Euclidean geometry consisting of those points in a plane that are a given distance from a given point, the centre. The distance between any of the points and the centre is called the radius....

 or sphere
Sphere
A sphere is a perfectly round geometrical object in three-dimensional space, such as the shape of a round ball. Like a circle in two dimensions, a perfect sphere is completely symmetrical around its center, with all points on the surface lying the same distance r from the center point...

. The correct "direction" of the radial line is from the radius point to a point on the arc or circle. This applies to its use in surveying.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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