Areas Related to Circles Notes: Class 10 Maths Chapter 11
Class 10 Maths Chapter 11 Areas Related to Circles covers the perimeter and area of a circle, and the areas of sectors and segments of a circle, along with combinations of plane figures.
Overview of Topics & Subtopics (Click to Jump)
1. Perimeter and Area of a Circle — A Review
Short Note:
• Circumference of a circle of radius r = 2πr. Area of a circle of radius r = πr².
2. Areas of Sector and Segment of a Circle
Short Note:
• Area of a Sector with angle θ (in degrees) at the centre = (θ/360°) × πr².
• Length of an Arc = (θ/360°) × 2πr.
• Area of a Segment = Area of the corresponding sector − Area of the triangle formed by the two radii and the chord.
3. Areas of Combinations of Plane Figures
Short Note:
• Areas of combined or composite figures (such as a square with circles/semicircles cut out or added) are found by adding or subtracting the areas of the basic shapes (circle, square, rectangle, triangle, sector) that make up the figure.