Welcome back to more science! Have you ever liked to build stuff? Like a bridge between two places? Try this out before we begin our experiment:
Take a sheet of copy paper and two cups. Separate the cups by just under the length of the piece of paper. Place that piece of paper across the gap. Try to put any object on the paper. Almost everything you put on it collapses the bridge!
Stay tuned to learn how to make a better bridge from that same piece of paper… without adding anything else to it!
Materials:
- A piece of copy paper (any size will do)
- Two cups
- Something to stack on the paper (coins, action figures, etc)
Procedure:
Fold your piece of paper accordion style, like in the image. The number of folds and thus the size of each fold is up to you! Experiment to see which works best!- Now place the folded piece of paper between the cups
- Test to see how much weight it can hold with the power of folds
Fold your piece of paper accordion style, like in the image. The number of folds and thus the size of each fold is up to you! Experiment to see which works best!Explanation:
When you put something between two objects, gravity pulls it down and adds a lot of stress to the material. If you put an unfolded piece of paper there, you can see the gravity pulling the paper down, making it slump inwards. Not very strong!
Now take a look at the side of your folds. You should notice the triangular parts of each. Triangles are long known in structural designs to be able to provide a lot of strength. The folds provide the strength needed for this.
You might be saying that a thicker piece of paper will work, too, right? Sure it will, but in terms of building materials, that is a lot more expensive than a thinner piece. So changing the shape of things is sometimes a better option.
Going further:
Does the number of folds make the paper stronger? If you had one fold versus ten folds, would you notice a difference in what the paper can hold before it breaks? Try it out! Just have patience when you try to fold the paper a lot of times! It’s tricky…
Here’s another trick. Take a regular piece of copy paper and try to stand it on its side on a table. Floops down! Where the paper hits the table, fold the paper in half and crease just a little. Not the whole length, just a little tiny crease. Now stand the paper where the crease is… The triangle is helping you out again!
Keep track of what you learned here today in a journal: you never know when you might ask a good science question, or need to apply what you’ve learned in an experiment or at school.
LOOKING FOR MORE science experiments? Find them here!
About the author:
Steve Davala has been teaching math and science to middle and high schoolers since 2000. He writes books, plays music, carves wood and he loves learning new things. Ask him a question at steve.davala@gmail.com.
