Eduki

Prisms are the extrusion of a 2d shape such that the cross-section remains the same. Pyramids are the extension of a 2d shape such that the cross-section keeps on decreasing by a constant factor thus at the end reducing the area to zero at a point. Here are some examples. All prisms have the same number of rectangular faces as the number of sides in the base. 

The difference between a prism and a pyramid

Observe the shapes given. Some of the shapes maintain their cross-section of the base along the height, while others have it decreased to zero at the highest point in the object. The objects with constant cross sections are prisms whereas others are known as pyramids. (Image: Illustrative mathematics)

Let’s take a prism and a pyramid with the same base. What can be seen with the cross-section area between the two? (Image: Illustrative mathematics)

Base area and Volume 

We have already discussed the prisms and pyramids being different in terms of the cross-section area being constant and decreasing with height respectively.  We also have learned that the total surface area of prisms and pyramids is given by the sum of the surface areas of all exposed surfaces only. The volume of those figures is given by how many unit cubes can be packed inside the given object. Let's have a look at the prism.