Primary Differences between Prisms and Pyramids

Definitions, Examples, and Non-Examples

FLAN 613 – Hannah Higgins

Definition of Prisms

A prism is a type of polyhedron that has a flat top that matches its bottom part. All other faces are parallelograms.

The specific name for a prism is based on the name of the 2 identical faces.

Definition of Pyramids

A pyramid is a polyhedron that has a point at the top. The base may be any polygon. All other faces must be triangles.

The specific name of a pyramid is based on the shape of the figure on the bottom of the pyramid.

Examples of Prisms

Photo Credit: http://www.flickr.com/photos/morethanmaths/4014100537/

Rectangular prism

Triangular prism

Examples of Pyramids

Photo Credit: http://i.images.cdn.fotopedia.com/flickr-2427530661-hd/World_Heritage_Sites/Middle_East/Egypt/Memphis_and_its_Necropolis_-_the_Pyramid_Fields_from_Giza_to_Dahshu/Giza_Necropolis/Pyramid_of_Khafre/Pyramid_of_Khafre-Giza_Necropolis-hd.jpg

Actual Pyramid

Mathematical representation of a

pyramid

Almost Prisms

• Cylinders look like prisms, but they are different. Circles are not considered polygons.

• Cylinders have a curved edge connecting the two circles, while prisms have clearly defined edges between rectangular faces.

Almost Pyramids

• Cones look like pyramids, but they are different. The base of a cone is a circle, not a polygon.

• Cones and pyramids both have a pointy top, but pyramids have clearly defined edges between triangular faces.

Photo Credits: http://www.flickr.com/photos/like_the_grand_canyon/3743007993/sizes/l/in/photostream/

http://www.freefoto.com/images/21/19/21_19_59---Traffic-Cones_web.jpg

Comparing and Contrasting Prisms and Pyramids

Both are polyhedrons.Both must have polygon faces.

Both cannot have circles.