Parts of a Circle

Front

What is a radius?

Back

A radius is a line segment that connects the center of a circle to any point on its circumference.

Front

What is a diameter?

Back

A diameter is a line segment that passes through the center of a circle and connects two points on its circumference. It is twice the length of the radius.

Tags

CCSS.HSG.C.A.2

Front

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

Back

The diameter is calculated by multiplying the radius by 2 (Diameter = 2 × Radius).

Tags

CCSS.7.G.B.4

Front

What is the relationship between radius and diameter?

Back

The diameter is always twice the length of the radius.

Tags

CCSS.7.G.B.4

Front

What is the circumference of a circle?

Back

The circumference is the distance around the circle. It can be calculated using the formula C = π × Diameter.

Tags

CCSS.7.G.B.4

Front

What is the formula for the area of a circle?

Back

The area of a circle is calculated using the formula A = π × Radius².

Tags

CCSS.7.G.B.4

Front

What is a chord in a circle?

Back

A chord is a line segment whose endpoints lie on the circumference of the circle.

Front

What is the center of a circle?

Back

The center of a circle is the point that is equidistant from all points on the circumference.

Front

What is the relationship between a radius and a chord?

Back

A radius can bisect a chord at a right angle if the chord is not a diameter.

Front

What is the term for the distance across a circle through its center?

Back

The term is diameter.