STEM Excellence Series: Empowering the Next Generation

DIAMETER

Diameter

Definition Of Diameter

Diameter is a line segment that passes through the center of a circle with both its endpoints lying on the circle.

More About Diameter

A diameter is the longest chord of a circle.
A diameter is double the radius of a circle.

Example of Diameter

In the circle shown, the line segments AB and PQ are the diameters of the circle. Notice that they have their endpoints on the circle and that both of them pass through the center O of the circle.

 example of  Diameter

Video Examples: How to Convert Diameter Into Feet : Math Conversions
 

Solved Example on Diameter

Ques: Sunny bought a circular ring of diameter 32 cm. Find the radius of the ring.

Choices:

A. 64 cm
B. 32 cm
C. 16 cm
D. 8 cm
Correct Answer: C

Solution:

Step 1: Diameter of a circle = 2 × radius.
Step 2: Therefore, radius =  example of  Diagonal.

Quick Summary

  • Diameter is the longest chord of a circle.
  • Diameter is double the radius of a circle.
\[ d = 2r \]

🍎 Teacher Insights

Use real-world examples like pizza or wheels to illustrate the concept. Have students draw circles and measure their diameters and radii.

🎓 Prerequisites

  • Circle
  • Radius
  • Center of a circle
  • Line segment

Check Your Knowledge

Q1: A circle has a radius of 8 cm. What is its diameter?

Q2: The diameter of a circle is 32 cm. What is the radius?

Frequently Asked Questions

Q: Is the diameter always twice the radius?
A: Yes, the diameter is always twice the length of the radius in any circle.

Q: Can a circle have more than one diameter?
A: Yes, a circle has infinitely many diameters.

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