Cirlces 1

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 circumference.

Front

What is the diameter of a circle?

Back

The diameter is twice the length of the radius and is the distance across the circle through its center.

Front

How do you calculate the circumference of a circle?

Back

Circumference = 2 × π × radius.

Front

What is the formula for the area of a circle?

Back

Area = π × radius².

Front

If the radius of a circle is 5, what is the diameter?

Back

Diameter = 2 × radius = 10.

Front

If the diameter of a circle is 20, what is the radius?

Back

Radius = diameter / 2 = 10.

Front

What does π (pi) represent in a circle?

Back

π is a constant approximately equal to 3.14, representing the ratio of the circumference to the diameter of a circle.

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the length of the radius.

Front

If the area of a circle is 50π, what is the radius?

Back

Radius = √(Area/π) = √(50) = 5√2.

Front

What is the circumference of a circle with a radius of 7?

Back

Circumference = 2 × π × 7 = 14π.