Page 72 - Mathematics Class - XI

TOPIC - 10: Conic Sections

ACTIVITY 10.1

OBJECTIVE

To construct different types of conic sections.

MATERIAL REQUIRED
 Transparent sheet  A pair of scissors
 White chart paper  Glue
 Hardboard

PRE-REQUISITE KNOWLEDGE
1. Knowledge of right circular cone
2. Knowledge of conic sections in standard form

PROCEDURE
1. Take a hardboard of convenient size and paste a white chart paper on it.
2. Make a right circular cone with the help of the transparent sheet in the shape of sector of a circle and fold
it, as shown in Fig. (a).

Fig. (a)

3. Form more than 4 such cones of the same size using transparent sheet. Put these cones on a hardboard.
4. Cut these cones with a transparent plane sheet in different positions (Figs. (b) to (e)).

DEMONSTRATION
1. When the transparent plane sheet cuts the first cone in such a way that the sheet is parallel to the base of
the cone. The section, so obtained, is a circle.

Fig. (b)

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