Circle vocab & arc measures

Front

What is the distance from the center of a circle to the boundary of the circle?

Back

Radius

Front

What is the longest chord in a circle that passes through the center?

Back

Diameter

Front

If the diameter of a circle is 10 inches, what is the radius?

Back

5 inches

Front

What is the measure of a full circle in degrees?

Back

360 degrees

Front

What is the formula to calculate the circumference of a circle?

Back

C = 2πr, where r is the radius.

Front

What is the measure of a semicircle in degrees?

Back

180 degrees

Front

What is an arc in a circle?

Back

A portion of the circumference of a circle.

Front

If an arc measures 90 degrees, what fraction of the circle does it represent?

Back

1/4 of the circle.

Front

What is the relationship between the central angle and the arc it subtends?

Back

The measure of the arc is equal to the measure of the central angle.

Front

What is an inscribed angle?

Back

An angle formed by two chords in a circle which have a common endpoint.