Page 63 - Mathematics Class - X

ACTIVITY 4.5

OBJECTIVE
To verify experimentally that the tangent at any point to a circle is perpendicular to the radius through that point.

MATERIALS REQUIRED

Coloured glazed paper Scissors/cutter White chart paper
Adhesive Geometry box

PRE-REQUISITE KNOWLEDGE

1. Various terms related to a circle 2. Tangent to a circle

THEORY:
1. Tangent: Line which touches the circle at any point.
2. Point of contact: The point at which the tangent touches the circle.

Fig. (a)

PROCEDURE:

1. Take a coloured glazed paper of suitable size and draw a circle of a suitable radius on it.
2. Cut out this circle and paste it on a white chart paper.
3. Take any three points, A, B and C on the circle (Fig. (b)). Form a number of creases (by folding the paper
through corners) through the three points, A, B and C. Out of these creases, select those which touch the
circle. These creases will be tangents to the circle.

Fig. (b)

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