A Circle - Maths Online Tutoring

A Circle - Maths Online Tutoring A circle is the locus of a point which moves in a plane in such a way that its distance from a given fixed point is always constant. The fixed point is called the center and the constant distance is called the radius of the circle. Terms related to a circle: - Radius is a line segment joining the center and a point on the circle is called its radius. Diameter is a chord of a circle passing through the Centre of the circle. A diameter is the longest chord of a circle. Diameter = 2 x radius Chord of a circle is a line segment joining any two points on the circle. Secant: - A line which intersects a circle in two distinct points is called a secant of the circle. Circumference: - The perimeter of a circle is called its circumference. Circumference = 2 r and Area of a circle = r^2 Where, r= radius of the circle and = 22 / 7 Example: - Find the radius of the circle if the diameter of the circle is 28 cm. Solution: - Diameter = 2 x radius Radius = Diameter / 2 = 28 / 2 = 14 cm. Example: - A circular field has the radius of 7 cm. Find the perimeter and area of the field. Solution: - Circumference = 2 r = 2 * (22 / 7) * 7 = 44 cm Area of a circle = r^2 = (22/7) * 7^2 =154 cm^2