Central Angles

Front

What is a central angle?

Back

A central angle is an angle whose vertex is at the center of a circle and whose sides are radii that intersect the circle.

Front

How do you calculate the measure of an arc?

Back

The measure of an arc is equal to the measure of the central angle that subtends the arc.

Front

What is the relationship between a central angle and its intercepted arc?

Back

The measure of a central angle is equal to the measure of the arc it intercepts.

Front

If the measure of a central angle is 60 degrees, what is the measure of the intercepted arc?

Back

The measure of the intercepted arc is also 60 degrees.

Front

What is the formula for the circumference of a circle?

Back

The circumference C of a circle is given by the formula C = 2πr, where r is the radius.

Front

How do you find the length of an arc?

Back

The length of an arc can be found using the formula: Arc Length = (θ/360) * C, where θ is the central angle in degrees and C is the circumference.

Front

What is the measure of a semicircle?

Back

The measure of a semicircle is 180 degrees.

Front

If arc AB measures 142 degrees, what is the measure of the central angle AOB?

Back

The measure of the central angle AOB is also 142 degrees.

Front

What is the total measure of all arcs in a circle?

Back

The total measure of all arcs in a circle is 360 degrees.

Front

If arc AYB measures 260 degrees, what type of angle is angle AOB?

Back

Angle AOB is a reflex angle because it measures more than 180 degrees.