# Exploring the relationships between different lengths in a circle.

- Author:
- Lua Shixiong

- Topic:
- Circle

## Instructions

**Part 1: Exploring the properties of the radii of a circle.**- Mark three points, A, B and C on the circle using .
- Using , draw a line from the centre O to points, A, B and C respectively.
- Measure the radius OA, OB and OC using .
- What do you notice about the length between each of these three points and the centre O?
- Drag the red dot to change the size of the circle.
- What do you notice about the radii as the size of the circle changes?

**Part 2: Exploring the properties of the Diameter of a circle.**- Using , draw a line from the red dot to green dot.
- Measure the diameter using .
- Compare it with the radius in part 1.
- What do you notice about the diameter of the circle and its radius?
- Drag the red dot to change the size of the circle.
- What do you notice about the diameter of the circle as the size of the circle increases?