Circles Basics
This is the distance around a circle.
What is the circumference?
An angle whose vertex is at the center of the circle is called this.
: What is a central angle?
The formula to find the circumference of a circle is this.
What is
C=2πr or 𝐶 = 𝜋 𝑑 C=πd?
In a circle, a chord that passes through the center is called this.
What is a diameter?
The arc of a circle measures 135°. The central angle is this, and the remaining major arc’s central angle measures this.
What are 135° and 225°?
A line segment from the center of a circle to any point on the circle is called this.
What is the radius?
The measure of a central angle is equal to the measure of this.
What is its intercepted arc?
The formula to find the area of a circle is this.
𝐴 = 𝜋 𝑟2
In a circle, chords equidistant from the center are this.
What is congruent?
A semicircle measures 180°. The central angle that intercepts it is this many degrees.
A: What is 180°?
A line segment that passes through the center of a circle and has endpoints on the circle is called this.
What is the diameter?
An arc measuring less than 180 degrees is called this.
What is a minor arc?
The length of an arc is a fraction of the circumference, calculated using this formula.
Arc Length= θ/360 ×2πr
A diameter perpendicular to a chord does this to the chord and its arc.
What is bisect?
If a circle has a central angle of 120°, the measure of the intercepted arc is this.
What is 120°?
A line segment with both endpoints on the circle but not passing through the center is called this.
What is a chord?
An arc measuring more than 180 degrees is called this.
What is a major arc?
The area of a sector (a "slice" of a circle) is found using this formula.
Sector Area= θ/360 ×πr2
If two chords in a circle are congruent, their corresponding arcs are also this.
What is congruent?
The arc of a circle measures 135°. The central angle is this, and the remaining major arc’s central angle measures this.
What are 135° and 225°?
This is a portion of the circumference of a circle.
What is an arc?
An arc measuring exactly 180 degrees is called this.
What is a semicircle?KT
If a circle has a radius of 5 cm, the length of an arc with a central angle of 60 degrees is approximately this.
60/360 ×2π×5= 6 1 ×10π≈5.24 cm
The perpendicular bisector of a chord passes through this point.
What is the center of the circle?
A Ferris wheel has a radius of 8 meters. A rider travels along an arc with a central angle of 135°. What is the arc length?
What is 135/360 × 2 𝜋 𝑟
135/360 × 2 𝜋 × 8 = 6 𝜋 ≈ 18.85
≈18.85 meters?