What are the formulas in areas related to circles? Areas Related to Circles Formulas CBSE Class 10 Maths The distance around the circle or the length of a circle is called its circumference or perimeter. Circumference (perimeter) of a circle = πd or 2πr, ... Area of a circle = πr2 Area of a semicircle = \frac { 1 }{ 2 } πr2 Area of quadrant = \frac { 1 }{ 4 } πr2.Area of a circle = π r. Length of an arc of a sector of a circle with radius r and angle with degree measure θ is= theta/360 *2*π *r. Area of a sector of a circle with radius r and angle with degree measure θ is theta/360 *π*r.
