kidzsearch.com > wiki

# Sphere

KidzSearch Safe Wikipedia for Kids.

A **sphere** is a shape in space that is like the surface of a ball. Most of the time, the terms ball and sphere are used as the same. But in mathematics, the precise (exact) definition only allows points in the 3 dimensional space which are uniformly and symmetrically located at a fixed length called radius of the sphere.

Examples of these are basketballs, superballs, and playground balls.

In other places sphere means the earth.^{[source?]}

A sphere is the 3 dimensional analogue of a circle.

## Volume

The volume of a sphere is given by the following formula

- [math]\!V = \frac{4}{3}\pi r^3[/math]

[math]\pi[/math] is a constant that is approximately equal to 3.1416.

## Surface Area

Surface area of a sphere

The surface area of a sphere is given by the following formula

- [math]\!A =4 \pi r^2[/math]

[[Category:Three-dimensional shapes