Radius and Diameter Flashcard

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 across the circle, passing through the center, and is twice the length of the radius.

Front

How do you calculate the diameter from the radius?

Back

Diameter = Radius * 2.

Front

How do you calculate the radius from the diameter?

Back

Radius = Diameter / 2.

Front

If a circle has a radius of 4 cm, what is its diameter?

Back

8 cm.

Front

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

Back

6 inches.

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the radius.

Front

If the diameter of a circle is 30 units, what is its radius?

Back

15 units.

Front

What is the formula for the area of a circle?

Back

Area = π * radius².

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle, calculated as Circumference = π * diameter.