Parts of a circle
for 5th grade

Identify different parts of a circle

As you know, a circle is a shape that is round and has no corners. There are different parts of a circle that you need to be able to identify. These parts include it's radius, diameter and cicumference. You should also know what a chord, a tangent, a sector, a segment and an arc are.

Radius: The radius of a circle is a straight line from the center of the circle to any point on the circle's edge.

Diameter: The diameter of a circle is the distance across the circle, passing through it's center. It's a measure of a straight line that starts at one point on the edge of a circle, goes through the center, and ends at another point on the edge of the circle.

Circumference: The circumference of a circle is the distance around the edge of the circle. It's like the perimeter of a circle.

Chord: A chord is a line segment that connects two points on the edge of a circle. It's a line that starts at one point on the edge of the circle and ends at another point on the edge of the circle that doesn't pass through the center.

Tangent: A tangent is a line that touches the edge of a circle at exactly one point without entering the circle.

Arc: An arc is a certain length along the edge of a circle.

Sector: A sector is a section of the circle that's bounded by two radii and an arc. It's like a slice of pizza that's been cut out of the circle..

Segment: A segment is a slice out of the side of a circle that's bounded by a chord and an arc. It is what you would get if you took a knife and sliced off a part of a circle with a single straight cut.

In this topic you are given diagrams of parts of a circle and have to identify what that part is called.