# What is formula for circumference and area of a circle? What is diameter and π?

What is formula for circumference and area of a circle? What is diameter and π? Learn in One Minute

Circumference is the arc length, of the circle, as if circle were opened up to a line segment

Diameter is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle, see picture to understand it

If, r, is the radius then diameter is 2 times r or 2r

Divide Circumference with Diameter and you get a unique constant π, which is equal to 22 divided by 7 or 3.14

Area is π, times, r, square. and circumference is, two times r, times pi as shown