Already have a TD account?

If you are already a Teachers' Domain user, sign in now to connect your Teachers' Domain and accounts.

Teachers' Domain sign-in name:

Organization:

Password:

Signing in now will connect your and Teachers' Domain accounts, so that in the future you will automatically be signed into Teachers' Domain when you come from .

Not yet registered?

First time here?

As a user, you may browse Teachers' Domain and view as many resources as you wish without registering.

However, for access to all fo the features of Teachers' Domain, we'll need a little more information. Learn More

You are now "Test Driving" Teachers' Domain

You may view up to 7 resources in this limited trial period.

You have 6 views remaining. Register now for unlimited free access and to download, share, and save resources. Learn More

You are now "Test Driving" Teachers' Domain

As a user, you may view as many resources as you like without registering.

About Registration:

Registering with Teachers' Domain is free and allows you to:

• View as many resources as you like
• Save, sort, and share resources using My Folders and My Groups
• Download resources to your desktop
• See standards correlations for your state

Thank you for "Test Driving" Teachers' Domain

You have viewed all seven resources permitted in this limited trial period. You may continue to browse the site, but to view, download, share, and save resources, you must register now. Registration is simple, safe, and free.

For more information:

Learn about our online Professional Development Courses, or review our Privacy Policy.

If you still have questions, please contact us.

Recommended for: Grades 3-8

Resource: Triangles: Designing a Newspaper Chair

Save to a folder

Media Type:
QuickTime Video

Length: 4m 21s
Size: 6.0 MB

Once it's been read, there's often little more to do with the daily newspaper than to add it to that towering stack of recyclables we collect each week. In this video segment, however, the ZOOM cast demonstrates how innovative design can turn this otherwise flimsy material into a relatively solid piece of furniture.

View Citation

Teachers' Domain, Triangles: Designing a Newspaper Chair, published January 22, 2004, retrieved on ,
http://www.teachersdomain.org/resource/phy03.sci.phys.mfw.znewschair/

Printer Friendly Version of Background Essay

Print Background Essay

One of the most common shapes in structural design is the rectangle. All around us, from floor to ceiling, in doorways and in window frames, columns and beams are attached at right angles to form rectangles of different dimensions. Despite its prevalence, the rectangle is not a particularly strong shape. The compressive force of a weight pushing down can easily cause a rectangle to deform -- to change into a parallelogram -- if the structure's joints pivot. This means that all of a square's stability is provided by the strength of joints.

In contrast, the triangle is an inherently strong shape. It cannot be deformed unless the length of a side changes or one of its joints breaks. This makes the triangle one of the most rigid and stable shapes used in construction today. In fact, rectangular parts of structures can be strengthened by adding supports that form triangles within the rectangle, either at the joints or diagonally across the entire figure.

In building their newspaper chair, the ZOOM cast members made good use of triangles, connecting joints with diagonal supports that strengthened and stabilized the square shapes they started with. In addition, the newspaper tubes they used to build their chair were both strong and easy to make. Like triangles, tubes provide a great deal of strength. At the same time, they are much lighter than supports made of solid material.