Class X Mathematics

Chapter 11: Areas Related to Circles

Standard NCERT & CBSE aligned study curriculum. Master concepts, track accuracy, revise weak areas, and challenge yourself with 9 customized practice modes.

Key Formulas & Equations

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Area of Sector

rTangent
A_{sec} = \frac{\theta}{360} \times \pi r^2

Area of circular sector of angle θ.

Length of Arc

L_{arc} = \frac{\theta}{360} \times 2\pi r

Length of circular sector boundary arc.

Related Formulas from Adjacent Chapters

Radius Tangent perpendicularity

OP \perp PT

[From Circles] Radius OP is perpendicular to tangent PT at contact point P.

Volume Conservation recasting

V_{final} = V_{initial}

[From Surface Areas and Volumes] Total volume remains constant when melting and recasting solids.