Understanding Circles: Radius and Diameter Flashcard

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 circumference.

Front

What is the diameter of a circle?

Back

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

Front

If a circle has a diameter of 8 meters, what is its radius?

Back

4 meters

Front

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

Back

24 cm

Front

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

Back

5 cm

Front

A circular pond has a radius of 9 meters. What is the diameter of the pond?

Back

18 meters

Front

The radius of a circle is 7 meters. What is the diameter?

Back

14 meters

Front

How do you calculate the diameter from the radius?

Back

Multiply the radius by 2.

Front

How do you calculate the radius from the diameter?

Back

Divide the diameter by 2.

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the length of the radius.