Area of a Circle

Front

What is the diameter of a circle?

Back

A line segment that passes through the center of the circle and whose endpoints lie on the edge/circumference of the circle.

Front

What is the radius of a circle?

Back

A line segment drawn from the center of a circle to the edge/circumference of the circle.

Front

What is the formula for the area of a circle?

Back

A = πr²

Front

What does π (pi) represent in circle calculations?

Back

A mathematical constant approximately equal to 3.14, used to calculate the circumference and area of a circle.

Front

How do you calculate the area of a circle with a radius of 5 units?

Back

A = πr² = 3.14 * 5² = 78.5 square units.

Front

What is the circumference of a circle?

Back

The distance around the circle, calculated as C = 2πr.

Front

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

Back

The radius is half of the diameter, so the radius is 5 units.

Front

What is the relationship between diameter and radius?

Back

The diameter is twice the radius (d = 2r).

Front

How do you find the area of a circle if you know the diameter?

Back

First, find the radius (r = d/2), then use the formula A = πr².

Front

What is the area of a circle with a radius of 7 units?

Back

A = πr² = 3.14 * 7² = 153.86 square units.