Chapter 10 · Class 10 CBSE · Formula Sheet

Circles Formulas — Class 10 CBSE

Study tangent to a circle, number of tangents from a point, and related theorems.

Key Formulas

Tangent Perpendicular

\text{Tangent} \perp \text{Radius at point of contact}

Tangent Lengths

\text{Tangents from external point are equal: } PA = PB

Angle in Semicircle

\angle \text{in semicircle} = 90°

Worked Examples

1Using: Area of Circle

Find the area of a circle with radius 7 cm.

Step 1: Area = pi x r^2

Step 2: = 22/7 x 49 = 154 sq. cm.

Answer: 154 sq. cm

2Using: Circumference

Find the circumference of a circle with radius 14 cm.

Step 1: C = 2 x pi x r

Step 2: = 2 x 22/7 x 14 = 88 cm.

Answer: 88 cm

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More Class 10 CBSE Formulas

Real Numbers Polynomials Pair of Linear Equations in Two Variables Quadratic Equations Arithmetic Progressions Triangles

Frequently Asked Questions

How many formulas are in Class 10 CBSE Circles?+

There are 3 formulas in the Circles chapter for Class 10 CBSE. Each formula is essential for solving problems in this topic.

How to remember Circles formulas easily?+

Practice regularly with worked examples, group related formulas together, and use SparkEd's interactive practice mode to reinforce your memory through problem-solving.

Are these Circles formulas enough for exams?+

Yes, these formulas cover the complete CBSE Class 10 syllabus for Circles. Practice applying them to different types of questions for full exam readiness.

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