Class 10 Maths Chapter 11 Areas Related to Circles Revision Notes

Quick revision notes for Class 10th Maths Chapter 11 — Areas Related to Circles — covering every formula for sector, segment and combined-figure area.

Last Updated: September 10, 2026

Class 10 Maths Chapter 11 – Areas Related to Circles: Quick Revision Notes

• Circumference of a circle = 2πr
• Area of a circle = πr²
• Length of an arc = (θ/360) × 2πr
• Area of a sector = (θ/360) × πr²
• Area of a sector (using arc length l) = (1/2) × l × r
• Area of a segment = Area of sector − Area of triangle = (θ/360)πr² − (1/2)r²sinθ
• Minor segment + Major segment = Area of circle
• Minor sector + Major sector = Area of circle
• Quadrant (θ=90°): Area = (1/4)πr²
• Semicircle (θ=180°): Area = (1/2)πr²
• Area of a ring/annulus (radii R > r) = π(R² − r²)
• Angle swept by minute hand = 6° per minute; by hour hand = 0.5° per minute
• Use π = 22/7 or 3.14 strictly as specified in the question

More on This Chapter

• NCERT Solutions – Chapter 11
• Extra Questions (HOTS) – Chapter 11
• Revision Notes – Chapter 11
• Class 10 Maths Book (Catalog Page)

Written by Satish

NCERTBooks.org is an independent educational resource run by a small team focused on making official NCERT textbooks easy to find, read, and download for students, parents, and teachers across India. We are not affiliated with NCERT or the Ministry of Education -- we organise publicly available NCERT content by class and subject, verify links against official sources, and build tools (like our in-browser reader) that make studying more convenient. Every guide we publish is written and reviewed by our team based on the actual NCERT curriculum and syllabus.