Circle Geometry

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

• 2 * r

• r^2

• 3.14 * r

• 2 * π * r

If the radius of a circle is 5 cm, what is its diameter?

• 15 cm

• 7 cm

• 3 cm

• 10 cm

What is the relationship between the radius and diameter of a circle?

• The diameter is twice the length of the radius.

• The diameter is three times the length of the radius.

• The diameter is half the length of the radius.

• The diameter and radius are equal.

What is this called?

• Chord

• Minor Arc

• Circumference

• Secant

If the diameter of a circle is 12 cm, what is its radius?

• 6 cm

• 8 cm

• 10 cm

• 4 cm

What is the name of the line segment that passes through the center of a circle and has its endpoints on the circle?

• diameter

• chord

• radius

• perimeter

What is the relationship between the radius and the circumference of a circle?

• The circumference is inversely proportional to the radius of the circle.

• The circumference is unrelated to the radius of the circle.

• The circumference is equal to the radius of the circle.

• The circumference is directly proportional to the radius of the circle.

What is the name of the point inside a circle that is the same distance from all points on the circle?

• perimeter

• corner

• edge

• center

What is the value of pi (π) in geometry?

• 4.6692

• 3.14159

• 1.61803

• 2.71828

If the circumference of a circle is 31.4 cm, what is its radius?

• 3 cm

• 10 cm

• 7 cm

• 5 cm