# Geometry - Spheres

Spheres are shapes we encounter daily, whether it's kicking a soccer ball or checking a location on a globe. A sphere is a perfectly round, three-dimensional object. Due to its lack of flat sides, we can't compute length times width times height to determine the volume of a sphere.  Instead, the formula changes to four-thirds pi r cubed. Yes, our good friend pi has made a comeback in today's free Geometry video on Spheres. In addition to learning about the volume of a sphere, you'll learn how to calculate the surface area of a sphere. Professor Burger also touches on how changing dimensions of a sphere impacts the volume. Then, combining our surface area and volume knowledge, he'll demonstrate how to find both measurements in composite figures. A composite figure is made from two or more geometric figures. Sounds complicated, but it's not so hard once you know the basics.

With 5 lectures, this video is a great tutorial on spheres and a good sample of our Geometry curriculum. Don't forget to click the forward button at the end of each lecture to move to the next one!