Parts of a Circle

Front

What is the diameter of a circle?

Back

The diameter is a line segment that passes through the center of the circle and has its endpoints on the circle. It is twice the length of the radius.

Front

What is the radius of a circle?

Back

The radius is a line segment that connects the center of the circle to any point on the circle. It is half the length of the diameter.

Front

What is the center of a circle?

Back

The center is the point that is equidistant from all points on the circle. It is the midpoint of the diameter.

Front

What is a chord in a circle?

Back

A chord is a line segment whose endpoints lie on the circle. It does not necessarily pass through the center.

Front

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

Back

The diameter can be calculated by multiplying the radius by 2 (Diameter = 2 x Radius).

Front

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

Back

The radius can be calculated by dividing the diameter by 2 (Radius = Diameter / 2).

Front

What is the relationship between the diameter and the radius?

Back

The diameter is always twice the length of the radius.

Front

What is the formula for the circumference of a circle?

Back

The circumference can be calculated using the formula C = π x Diameter or C = 2π x Radius.

Front

What is the area of a circle?

Back

The area can be calculated using the formula A = π x Radius².

Front

What is a semicircle?

Back

A semicircle is half of a circle, formed by cutting a whole circle along its diameter.