## Properties of a Semi-Circular Area

This tool calculates the basic geometric properties of a semi-circular area. Enter the shape dimensions R or D below. The calculated results will have the same units as your input. Please use consistent units for any input.

 R = ...or D = Geometric properties: Radius = Diameter = Area = Perimeter = Arc length = yc =

## Definitions

### Geometry

The area A, the perimeter P and the arc length L of a semi-circular area, with radius R, can be found with these formulas:

$\begin{split} A & = \frac{\pi R^2}{2} \\ P & = \left(\pi+2\right) R \\ L & = \pi R \end{split}$

The centroid (center of gravity) of the semi-circular area is located at a distance from the diameter that defines its border, given by the formula:

$y_c = \frac{4 r}{3 \pi}$