Identifying Parts of a Circle

The video tutorial explains the properties of circles, including how they differ from polygons. It covers naming circles by their center point, measuring the radius, and understanding chords, with a focus on the diameter as the longest chord. The relationship between radius and diameter is discussed, highlighting that the radius is half the diameter and the diameter is twice the radius. The tutorial also explains how to calculate the circumference of a circle using either the radius or diameter.

What distinguishes a circle from polygons?

• Circles have vertices.

• Circles have a set of edges.

• Circles are made up of an infinite number of points equidistant from the center.

• Circles are always larger than polygons.

How is a circle typically named?

• By the length of its radius.

• By the length of its diameter.

• By its center point.

• By the number of points it contains.

What is the radius of a circle?

• Half the diameter of the circle.

• The distance from any point on the edge to the center.

• The longest chord of the circle.

• Twice the diameter of the circle.

What is the diameter of a circle?

• The shortest chord in the circle.

• The distance around the circle.

• Half the radius.

• Twice the radius.

What is the relationship between the radius and the diameter of a circle?

• The radius is twice the diameter.

• The diameter is twice the radius.

• The diameter is half the radius.

• There is no relationship.

Which of the following is true about the chord of a circle?

• It is a segment whose endpoints lie on the circle.

• It can never be longer than the radius.

• It is the same as the circumference.

• It is always equal to the radius.

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

• 20 units

• 15 units

• 5 units

• 10 units

How can the circumference of a circle be calculated?

• Radius plus diameter times pi.

• Pi divided by the diameter.

• 2 times pi times the radius.

• Pi times the radius squared.

What does measuring the circumference involve?

• Measuring the distance across the circle through the center.

• Measuring the distance around the circle.

• Calculating the area of the circle.

• Counting the number of points on the circle.

Which formula is correct for finding the circumference if you know the diameter?

• Circumference = radius * pi

• Circumference = pi * diameter

• Circumference = 2 * radius

• Circumference = diameter / pi