Geometry Help
 

Surface Area of a Sphere

We previously calculated the volume of a sphere, now we are going to calculate the surface area of a sphere. Let's look at the green sphere. Each sphere has a radius which we have labelled r. The radius of any sphere is the distance between the center of the sphere and the surface. It doesn't matter where on the surface of the sphere you measure the radius 'r' to. The distance between the center point of the sphere and any point on the surface of the sphere is the same.

Surface area of a sphere

Equation for the surface of the sphere

The formula for calculating the surface of a sphere is given by:

Surface area of sphere

In another word, the surface area of a sphere is four pi r squared or four time pi times r times r where pi is given by:

pi

That's it. Now you can calculate the surface area of any spheres!