Page 81 - Mathematics Class - XI

ACTIVITY 10.4

OBJECTIVE

To construct an ellipse when two fixed points are given.

MATERIAL REQUIRED
 A cardboard  Board pins/nails

 White paper  Adhesive

 Nylon  Chart paper
 Wires/Threads  Pen/pencil

PRE-REQUISITE KNOWLEDGE

1. Knowledge of concept of conic section
2. Knowledge of ellipse

PROCEDURE

1. Take a rectangular cardboard of size 30 cm × 25 cm and paste a chart paper on it.
2. Draw a horizontal line on the chart paper and mark two fixed points F and F on it such that the distance
2
1
between them is (say) 10 cm. Fix two nails at the points F and F .
1 2
3. Take a string or thread whose length is more than the distance between the two fixed points F and F (say)
1
2
14 cm.

Fig. (a)

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