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plane surfacesclick to hear

Set of points on a plane that describes an area of space.
plane surfaces parts of a circle quadrant center arc radius sector diameter semicircle circumference

parts of a circle click to hear

Circle: closed plane curve; all its points are the same distance from a fixed point (center).

quadrant click to hear

Quarter of a circle’s circumference; it corresponds to an arc of 90°.

center click to hear

Point located at the same distance from every point on the circle’s circumference.

arc click to hear

Section of a circle between two points on the circle.

radius click to hear

Line that joins a point on a circle’s circumference to its center; it is one half of the diameter.

sector click to hear

Surface bounded by two radii and an arc of a circle.

diameter click to hear

Line that connects two points on a circle’s circumference and passes through its center.

semicircle click to hear

A half circle that is delimited by its diameter.

circumference click to hear

Length of a circle that corresponds to the product of its diameter and pi.