Radius, Diameter, and Circumference

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 edge.

Front

What is the diameter of a circle?

Back

The diameter is the distance from one edge of the circle to the opposite edge, passing through the center.

Tags

CCSS.HSG.C.A.2

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

If the radius of a circle is 18 m, what is the diameter?

Back

Diameter = 2 × radius = 2 × 18 m = 36 m.

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle with a radius of 54 m?

Back

Circumference = 2 × π × 54 m ≈ 339.12 m.

Tags

CCSS.7.G.B.4

Front

Is the red line a radius or diameter of the circle?

Back

If it passes through the center and connects two points on the edge, it is a diameter.

Front

What is the relationship between radius and diameter?

Back

The diameter is twice the length of the radius.

Tags

CCSS.7.G.B.4

Front

What is π (pi)?

Back

π (pi) is a mathematical constant approximately equal to 3.14, used in calculations involving circles.

Tags

CCSS.HSG.GMD.A.1

Front

If the diameter of a circle is 16 m, what is the radius?

Back

Radius = diameter / 2 = 16 m / 2 = 8 m.

Tags

CCSS.7.G.B.4

Front

What does the term 'circumference' refer to?

Back

Circumference refers to the total distance around the circle.