# Circumference Formula

The circumference of a closed curve or circular object is the linear distance around its edge. The circumference of a circle is a special importance in geometry and trigonometry.

The Circumference Formula requires either the radius or the diameter of the circle for its calculation.

$\LARGE Circumference\;of\;a\;Circle(C)=2\pi r=\pi d$

Where,

C is the circumference of the circle.
d is the diameter of the circle.
r is the radius of the circle.

### Solved Examples

Question 1: The radius of a circle is 2 inches. What is the circumference of the circle?

Solution:

Given,
Radius of the circle = r = 2 inCircumference of the circle
= 2πr
= 2 $\times$ π $\times$ 2 in
= 12.56 in

#### Practise This Question

The IUPAC name of crotonaldehye is