Radius
Definition
The radius is the distance from the center of a circle or sphere to any point on its circumference or surface.
Analogy
Imagine you are at the center of a circular track, and your friend is standing at different points along the edge. The distance between you and your friend is like the radius of the track - it tells you how far away your friend is from the center.
Related terms
Circumference: The circumference is the distance around a circle. It can be calculated using the formula C = 2πr, where r is the radius.
Diameter: The diameter is twice the length of the radius. It is a straight line passing through the center of a circle or sphere and touching two points on its circumference or surface.
Arc Length: Arc length refers to a portion of a curve in a circle's circumference. It can be calculated using θ/360° × 2πr, where θ represents an angle in degrees and r is the radius.
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