Circle Flashcards
What is a circle?
A circle is a plane figure bound by a curve, formed by the locus of a point that moves so that it is always at a fixed distance from a stationary point called the “Centre.”
What is the radius of a circle?
The distance from the center to any point on the circle
What is the diameter of a circle?
The length of a straight line between two points on the curve, passing through the center. It is twice the radius.
What is the circumference of a circle?
The linear length of the entire curve, equal to πD or 2πr.
What is an arc?
A part of the circle between any two points on the circumference or periphery.
What is a chord?
A straight line joining the ends of an arc. (The longest chord of the circle is the diameter.)
What is a segment of a circle?
A part of the circle or area bound by the arc and chord.
What is a sector of a circle?
The part of a circle bounded by two radii meeting at an angle and an arc.
What is the tangent of a circle?
A straight line just touching the circle at a point, without cutting or passing through it.
What is the point of tangency?
The point where the tangent touches the circle.
What is the angle between the radius and the tangent at the point of tangency?
90 degrees.
What is a quadrant?
Part of a circle with radii making 90 degrees with each other (one-fourth of the circle).
What is half of a circle called?
A semi-circle.
What are concentric circles?
Circles with a common center.
What are eccentric circles?
Circles within a circle but with different centers.
