Parts of a Circle

Front

What is the radius of a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

What is the diameter of a circle?

Back

The diameter is the distance across the circle through its center, equal to twice the radius.

Tags

CCSS.HSG.C.A.2

Front

What is the circumference of a circle?

Back

The circumference is the total distance around the circle.

Front

How do you calculate the circumference of a circle?

Back

Circumference = 2 × π × radius or Circumference = π × diameter.

Tags

CCSS.7.G.B.4

Front

What is π (pi)?

Back

π (pi) is a mathematical constant approximately equal to 3.14, representing the ratio of the circumference of a circle to its diameter.

Tags

CCSS.HSG.GMD.A.1

Front

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

Back

The diameter is 10 cm (diameter = 2 × radius).

Tags

CCSS.7.G.B.4

Front

If the radius of a circle is 7 m, what is the circumference?

Back

Circumference = 2 × π × 7 m ≈ 43.98 m.

Tags

CCSS.7.G.B.4

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the length of the radius.

Tags

CCSS.7.G.B.4

Front

What part of the circle is the center?

Back

The center is the point that is equidistant from all points on the circumference.

Front

What is a chord in a circle?

Back

A chord is a line segment whose endpoints lie on the circle.