Chp 8.1 - Radius and Diameter

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 from one edge of the circle to the opposite edge, passing through the center.

Front

If the radius of a circle is 4 mm, what is the diameter?

Back

The diameter is 8 mm (diameter = 2 x radius).

Front

How do you find the radius if you know the diameter?

Back

Divide the diameter by 2.

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the length of the radius.

Front

If a pizza has a diameter of 16 inches, what is the radius?

Back

The radius is 8 inches.

Front

Is the line from the center to the edge of a circle a radius or diameter?

Back

It is a radius.

Front

If the radius of a circle is 12 inches, what is the circumference? (Use C = 2πr)

Back

The circumference is 75.4 inches (C = 2 x π x 12).

Front

What is the formula to calculate the area of a circle?

Back

Area = πr².

Front

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

Back

The radius is 5 cm.