Finding the Diameter of a Circle Given the Radius | Math with Mr. J
From Math with Mr. J
3 min4th5thMath
Summary
How to name the parts of a circle -- the radius, diameter, and chord -- and how the radius and diameter relate. Mr. J labels each part clearly.
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Teaching resources
Discussion questions
The radius reaches from the center to the edge; the diameter crosses the whole circle through the center.
- What is the radius of a circle? The diameter?
- How is the diameter related to the radius?
- What is a chord?
Quick work-a-long
Words to know: radius, diameter, chord, center
- Draw a circle and label its radius and diameter.
- If the radius is 5, find the diameter.