Class 10 -Lab Activity - lengths of tangents drawn from an external point to a circle are equal.

Objective
To verify experimentally that lengths of tangents drawn from an external point to a circle are equal.

Prerequisite Knowledge
1) Tangent to a circle.
2) Length of a tangent.

Materials Required
Coloured papers, sketch pens, a pair of scissors, geometry box, fevicol.

Procedure
1. Cut a circle of any radius from a coloured paper and paste it on a paper.
2. Take any point P on the circle.
3. From P, fold the paper in such a way that it just touches the circle at P.
4.Press it and unfold to get a tangent PQ.
5. From A, fold the paper to get tangent AQ.
6. Fold the circle along OA.
7 .Join OP, OA, OQ.

Observation
PQ = ______
AQ = ______
Students observe that point P coincide with A
∴ PQ = AQ

Result
Thus it is verified that lengths of tangents drawn from an external point to a circle are equal.

Learning Outcome
Students will learn how to measure tangents from an external point to a circle by using paper folding.

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