Radius and diameter of a circle

Marking radius and diameter of a circle and understand their relation.

Objectives

 * 1) Radius is a straight line joining centre of a circle to any point on the circumference.
 * 2) Ability to learn the use of compass.
 * 3) Skill of drawing the circle accurately.

Estimated Time
20 minutes

Prerequisites/Instructions, prior preparations, if anyrio
Prior knowledge of points, lines and line segments, formation of a circle.

Materials/ Resources needed
Different coloured papers, compass, scale, pencil and scissors.

Process (How to do the activity)
Instructions to the teacher: Instructions to the student:
 * 1) The teacher distributes the paper to the students.
 * 2) Shows them how to use compass and draw a circle.
 * 3) Ask every student to make 2 equal parts by folding.
 * 4) What happens if it is folded again to get equal parts?
 * 5) Ask the students to identify the folded lines/marks
 * 1) Draw a circle of given radius.
 * 2) Cut out the circle.
 * 3) Fold the circle into two equal halves.
 * 4) Again fold into further equal halves.
 * 5) Observe and mark the folded line.
 * 6) Identity the diameter and radius.
 * Evaluation
 * 1) Was the student successful in marking radius and diameter?
 * 2) Was the student successful in folding and marking?
 * 3) Was the student able to relate radius and diameter.
 * Question Corner
 * 1) How many such radii and diameters can be drawn to a given circle?