Shape Hunting: Cylinders, Prisms And Pyramids (1980)

[Music] he [Music] [Music] [Music] what has one curved surface and can roll in two directions a cylinder the curved surface is like a rolled rectangle a cylinder also has two flat surfaces that are circular they are called bases you may be able to see only one of these bases at a time now let's go hunting for cylinders [Music] w [Music] a cylinder has one curved rectangular surface and two flat surfaces shaped like [Music] circles what looks like a box you can't open a rectangular prism six sides or faces are shaped like rectangles two faces meet to form an edge how many [Music] edges three edges meet at a point called a Vertex how many [Music] vertexes rectangular prisms lying flat or Standing Tall let's hunt for them [Music] watch six rectangular faces what is it a rectangular [Music] [Laughter] prism when is a triangle not a triangle when it's the Triangular face of a pyramid every Pyramid has three or more triangular faces the base gives the pyramid its name this is a square pyramid a prism can have triangular faces too then we call it a triangular prism the other faces of this prism are rectangles prism and pyramids and triangles let's on for them a pyramid three or more triangular faces and a base a triangular prism two triangular fa B [Music] [Music] [Music] for