8C.5.4 Surface area of a cylinder

A cylinder can be considered a circular prism, so finding the surface area is a lot like a regular prism:

  1. Consider how many sides the shape will have
  2. Find the area of each side
  3. Find the sum of the areas

Pre-Class Assignment:

In-Class Assignment

  • p186 #3, 5, 6, 8, 9, 10, 11, 12, 13

 

8C.5.3 Surface Area

Every 3d shape has a surface.  The total area of that shape is the surface area.  If the 3d shape is a polyhedron (something with flat faces) then it is usually pretty easy to find the total area of the surface:

Resources:

  • What is a prism? Watch the Prism Video on Youtube if you're not sure.  All the prisms we will be looking at in this course are "right prisms"

Assignment:

In Class Assignment:

  • HW 5.3 p180 #3-8, 10, 12, 13, 15
  • Constructing prisms from nets and finding their surface area
 

8C.5.2 Nets

What are other ways to represent a 3d shape in two dimensions?  We saw last class that you can use one of several different views, but we can also take the shape and look at its "skin".  When you cut a polyhedron along some of its edges to lay it flat, we get a net:

Resources:

Fun Ideas with Nets and Networks

Pre-Class Assignment:

  • Before next class, read through the notes and copy them down into your notebook.
  • Think about the following 2 questions and add a comment to this article with your answer:
    • Do you think a net is more or less effective at representing a 3d shape two dimensionally than the 3 views?
    • Is there a way to figure out how many faces, vertices and edges a shape will have by looking at its net?  Use the examples of the triangular prism and the rectangular prism to help you.

In-Class Assignment:

  • P173 #3, 4, 6, 7, 8, 9, *12 *13
  • Koninsberg Network Problem
  • Circle Challenge peer editing
 
   

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