Properties of Circles
Learn about circles, including radius, diameter, chords, arcs, sectors, segments, and tangents. Let’s get started! 🚀
Video Lesson
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Flashcards
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🛎️ Properties of a Circle
- The diameter goes through the centre and is twice the radius.
- A sector is made from two radii and the arc between them.
- A tangent touches the circle at one point and is perpendicular to the radius.
🛎️ Finding Points with Circles
- All points the same distance from a point lie on a circle, and that distance is the radius.
- The intersections of circles show the possible answers.
Practice Questions
Test your understanding
What is the constant distance from the centre of a circle to any point on its edge called?
Correct! 🎉 +10 pointsNot quite right
The radius is the constant distance from the centre to any point on the circle's edge.
What do we call a straight line that touches a circle at exactly one point?
Correct! 🎉 +10 pointsNot quite right
A tangent touches the circle at exactly one point and is perpendicular to the radius at that point.
What is the part of a circle enclosed by a chord and the arc above it called?
Correct! 🎉 +20 pointsNot quite right
A segment is the area enclosed by a chord and the arc above it.
A circle has a diameter of 16 cm. What is its radius?
Correct! 🎉 +20 pointsNot quite right
The radius is half the diameter, so 16 ÷ 2 = 8 cm.
A tangent touches a circle at exactly one point. At this point, what is the angle between the tangent and the radius?
Correct! 🎉 +20 pointsNot quite right
A tangent is always perpendicular to the radius at the point of contact, forming a 90° angle.
A circle has a radius of 7 cm. What is the length of the longest chord in the circle?
Correct! 🎉 +30 pointsNot quite right
The diameter is the longest chord in a circle, and it is twice the radius: 7 × 2 = 14 cm.
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Explore the fundamental parts and properties of a circle
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