# Radius and diameter of a circle

Jump to navigation
Jump to search

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

### Objectives

- Radius is a straight line joining centre of a circle to any point on the circumference.
- Ability to learn the use of compass.
- 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:

- The teacher distributes the paper to the students.
- Shows them how to use compass and draw a circle.
- Ask every student to make 2 equal parts by folding.
- What happens if it is folded again to get equal parts?
- Ask the students to identify the folded lines/marks

Instructions to the student:

- Draw a circle of given radius.
- Cut out the circle.
- Fold the circle into two equal halves.
- Again fold into further equal halves.
- Observe and mark the folded line.
- Identity the diameter and radius.

- Evaluation

- Was the student successful in marking radius and diameter?
- Was the student successful in folding and marking?
- Was the student able to relate radius and diameter.

- Question Corner

- How many such radii and diameters can be drawn to a given circle?