# Dome Sweet Dome - Science Sweet Dome.pdf · sciencenorth.ca/schools 2 Introduction A geodesic dome…

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sciencenorth.ca/schools 1

Science North is an agency of the Government of Ontario

Science Olympics

Description Geodesic domes are made of interconnected triangles that approximate the

shape of a sphere. This project shows you how to build a geodesic dome

using rolled-up newspapers and tape. This activity lends itself well to a

Science Olympics-style competition.

Duration 120 minutes

Group Arrangement 5-6 students

Setting classroom

Vocabulary Structures

Tension

Torsion

Dome

Weight

Science and Technology Curriculum Expectations Understanding Structures and Mechanisms: Strong and Stable

Structures

Understanding Structures and Mechanisms: Forces Acting on

Structures and Mechanisms.

Cross Curricular Links Language- Oral Communication

Materials Newspapers

Magazines (for testing the strength of the domes)

Ruler

Scissors

Background Science Olympics are a great way to engage your students in hands-on science. They are made up of a series of

interactive, inquiry-based activities that are used as a competition between classrooms or groups within the

same classroom. The element of competition can be a great motivator to get students involved, and this

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Introduction A geodesic dome is a structure made of interconnected struts that approximate the shape of a sphere (or

hemisphere). The struts are joined together in triangles, with the vertices of the triangles designed to fall

approximately on the sphere. The struts form a rigid network that transmits stress forces throughout the

structure. The sides of the triangles form great circles (geodesics) over the surface of the sphere.

Geodesic domes have some very interesting properties. Since the structure approximates a sphere, geodesic

domes have very high surface-to-volume ratios. In fact, geodesic domes enclose more volume per unit weight

structure that increases in strength as the size of the structure is increased.

Activities Stack three flat sheets of newspaper together. Starting in one corner, roll the sheets up together as tightly as you

can to form a tube. When you reach the other corner, tape the tube to keep it from unrolling. Repeat until you

have 65 tubes.

Now cut down the tubes to make 35 "longs" and 30 "shorts."

Longs: Cut off both ends of a tube until it is 71 centimeters long. Use this tube as a model to create 34 more

longs. Be sure to mark all the longs clearly in some way, such as with colored marker at each end, so you can

tell them apart from the shorts. Decorate the tubes if you like.

Shorts: Cut off both ends of another tube until it is 66 cm long. Use this tube as a model to create 29 more

shorts. Decorate the tubes if you like.

First, tape 10 longs together to make the base of the dome.

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Tape a long and a short to each joint. Arrange them so that there are two longs next to each other, followed by

two shorts, and so on, as shown below.

Tape the tops of two adjacent shorts together to make a triangle. Tape the next two longs together, and so on all

the way around.

Connect the tops of these new triangles with a row of shorts. The dome will start curving inward.

At each joint where two shorts and two longs come together tape another short sticking straight up. Connect

this short to the joints on either side with longs, forming new triangles.

Connect the tops of these new triangles with a row of longs.

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Finally, add the last five shorts so that they meet at a single point in the center of the dome. You might need to

stand inside the dome to tape them together.

Conclusion

Once the teams have finished building their domes, you can begin your competition with the following

questions:

1. How much does the dome weigh?

2. How strong is it? To test your dome's strength, see how many magazines you can load on top. Adult

supervision is recommended for this step. Add magazines gradually. Observe the dome carefully for

signs of impending failure.

3. What was the strength-to-weight ratio of the dome?

4. Did the results surprise you? Why or why not?

5. What was the hardest part about creating the dome?