## radius- (MATH) The distance from the
point of intersection of the axes of symmetry of a closed
curve. More specifically, the distance from the center of a circle
to its circumference, from the center of a sphere
to its surface, or from the center of a regular
polygon to any one of its vertices.
All radii of a circle or sphere are equal; and it is generally profitable
to consider only the longest and shortest radii (semi-major and semi-minor
axes) of an ellipse. The
**radius of curvature**,*r*, at any point of a curve is*r*= 1/*κ*, where*κ*is the curvature.
• GEOMETRY - (ASTRON) An old instrument for measuring the angular distance between two celestial objects.
| |||||

Home • About • Copyright © The Worlds of David Darling • Encyclopedia of Alternative Energy • Contact |