Circles

Front

What is the radius of a circle?

Back

The radius is a line from the center point to the edge of the circle.

Front

What is the area of a circle?

Back

The area is the space contained inside of a circle.

Front

What does 'circumference' mean?

Back

Circumference is the distance around a circle.

Front

What is the diameter of a circle?

Back

The diameter is a line that crosses through the center and touches each edge.

Front

How do you calculate the circumference of a circle?

Back

Circumference can be calculated using the formula c = 2πr, where r is the radius.

Front

If a circle has a radius of 6, what is its diameter?

Back

The diameter is 12, since diameter = 2 * radius.

Front

What is the formula for the area of a circle?

Back

The area can be calculated using the formula A = πr².

Front

If a DVD has a diameter of 15 millimeters, what is its radius?

Back

The radius is 7.5 millimeters, since radius = diameter / 2.

Front

What is the relationship between radius and diameter?

Back

The diameter is twice the length of the radius.

Front

What is the circumference of a circle with a radius of 5?

Back

The circumference is 10π, since c = 2πr.