Finding the volume of a cone or cylinder is rather simple if you know the basics of using pi. Finding the volume of a sphere, however, can be much more difficult. The formula is actually very simple.
ISAIAH LOPEZ
The area of a circle is equal to pi times the radius squared, or πr². You probably already know this if you're here. Following this pattern, you might assume that the volume a sphere is πr³. This is incorrect, but it is partially right. The formula for the area of a sphere is actually 4/3(πr³). By this point, you are probably confused as to what the 4/3 is for. There is actually a deep reason why it is there, but we'll save that for another lesson.
As mentioned previously, the volume of a sphere is equal to 4/3(πr³), so let's do some examples. First, we'll use a sphere with a radius of 3. The volume of this would be 4/3 * (π(3)³), which would simplify to 4/3 * 27π, giving an answer of 36π. Let's try another sphere with a volume of (32/3)π. This time, we'll try to find the radius. We can make an equation, 4/3 * (πr³) = (32/3)π. First, we'll multiply both sides by 3/4, the reciprocal of 4/3, leaving πr³ = 8π.
I hope this article made it easier for you to understand how to calculate the volume of a sphere. Make sure to check the articles for finding the volume and area of other shapes.