Class 10 Maths Chapter 11 (formerly Chapter 12 before Constructions was removed in rationalisation), Areas Related to Circles, derives and applies the formulas for the length of an arc and the areas of sectors and segments of a circle of radius r and central angle θ.
What Class 10 Mathematics (Ganit — Hindi Medium) Chapter 11 Covers
11.1 Areas of Sector and Segment of a Circle defines minor and major sectors (bounded by two radii and an arc) and minor and major segments (bounded by a chord and an arc), derives arc length l = θ/360° × 2π r and area of a sector = θ/360° × π r2, and computes the area of a segment of a circle as Area of corresponding sector OAPB – Area of △ OAB (with Area of major sector = π r2 – Area of minor sector and Area of major segment = π r2 – Area of minor segment).
Exercises in Chapter 11
- Exercise 11.1 (14 Questions) covers sector areas, clock minute-hand swept areas (6° per minute), chord subtending 60°, 90° or 120° at the centre, a horse tied to a peg at the corner of a square grass field, silver wire brooch sectors, umbrella ribs, car wiper blade sweep areas, lighthouse warning sector, and round table cover designs.
Read Class 10 Mathematics (Ganit — Hindi Medium) Chapter 11 Online
More Chapters
- Previous: Chapter 10: वृत्त (Circles)
- Next: Chapter 12: पृष्ठीय क्षेत्रफल और आयतन (Surface Areas and Volumes)
- English medium: Class 10 Maths Chapter 11 PDF in English
- All Mathematics (Ganit — Hindi Medium) chapters and the other Class 10 books: Class 10 NCERT books 2026-27
- All Class 1 to 12 NCERT Textbooks: NCERT Books PDF (Class 1–12)
- Every book chapter by chapter: NCERT chapter wise PDF
FAQ
What are the formulas for arc length, area of a sector, and area of a segment of a circle?
For a circle of radius r and sector angle θ (in degrees): (1) Length of arc = θ/360° × 2π r; (2) Area of sector = θ/360° × π r2; (3) Area of segment = θ/360° × π r2 – Area of △ OAB.
How many degrees does the minute hand of a clock sweep in 1 minute?
The minute hand completes one full revolution (360°) in 60 minutes, so it sweeps an angle of 360°/60 = 6° per minute.