Circumference of Circles

Front

What is the diameter of a circle?

Back

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

Front

How do you calculate the diameter if you know the radius?

Back

The diameter is calculated by multiplying the radius by 2 (Diameter = 2 x Radius).

Front

What is the circumference of a circle?

Back

The circumference of a circle is the total distance around the circle.

Front

What is the formula for calculating the circumference of a circle?

Back

The formula for calculating the circumference is C = πd or C = 2πr, where d is the diameter and r is the radius.

Front

If the radius of a circle is 10 feet, what is the circumference?

Back

The circumference is 62.83 feet (C = 2πr = 2π(10)).

Front

What is the relationship between diameter and circumference?

Back

The circumference is directly proportional to the diameter, with the constant of proportionality being π (C = πd).

Front

How do you find the radius if you know the circumference?

Back

To find the radius from the circumference, use the formula r = C/(2π).

Front

What is the circumference of a circle with a diameter of 21 feet?

Back

The circumference is approximately 65.94 feet (C = πd = π(21)).

Front

What does the term 'circumference' refer to?

Back

Circumference refers to the distance around the edge of a circle.

Front

What is the radius of a circle?

Back

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