Radius and Diameter of Circles

Front

What is the definition of diameter in a circle?

Back

The diameter is the longest distance across a circle, passing through the center, and is equal to twice the radius.

Front

What is the definition of radius in a circle?

Back

The radius is the distance from the center of the circle to any point on its circumference.

Front

If the diameter of a circle is 16 cm, what is the radius?

Back

The radius is 8 cm, since the radius is half of the diameter.

Front

If the radius of a circle is 18 cm, what is the diameter?

Back

The diameter is 36 cm, since the diameter is twice the radius.

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the length of the radius.

Front

How do you calculate the circumference of a circle using the diameter?

Back

Circumference can be calculated using the formula C = π * diameter.

Front

How do you calculate the circumference of a circle using the radius?

Back

Circumference can be calculated using the formula C = 2 * π * radius.

Front

What is the formula for the area of a circle using the radius?

Back

Area can be calculated using the formula A = π * radius².

Front

What is the formula for the area of a circle using the diameter?

Back

Area can be calculated using the formula A = (π/4) * diameter².

Front

Is a line segment that connects two points on the circumference of a circle and passes through the center a radius or diameter?

Back

It is a diameter.