Parts of a circle

When you measure around the outside of a circle, you are measuring the _________.

• circumference

• diameter

• radius

• Pi

What is the distance from the center of the circle to any point on the circle called?

• circumference

• diameter

• radius

• Pi

Which of these terms describes the line segment that passes through the center of the circle and touches two points on the circle (the edges)?

• circumference

• diameter

• radius

• Pi

If the diameter of a circle is 12 cm, what is the radius?

• 1cm

• 2cm

• 3cm

• 6cm

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

• Area=π×r

• Area=π×d

• Area=π×r^2

• Area=d^2

What is the area of a circle with a radius of 4 cm? Use π≈3

• 12cm^2

• 16 cm^2

• 48 cm^2

• 24 cm^2

What is the diameter of a circle if its radius is 8 cm? Use π≈3

• 8 cm

• 16 cm

• 4 cm

• 64 cm

What is the circumference of a circle with a diameter of 10 cm? Use π≈3

• 10 cm

• 20 cm

• 30 cm

• 40 cm

If the radius of a circle is doubled, how does the area change?

• It doubles

• It triples

• It quadruples

• It remains the same

Which of the following is the correct formula for the circumference of a circle?

• Circumference = 2πr

• Circumference = πr^2

• Circumference = πd^2

• Circumference = 2πd